Development of Machine Learning Potentials for Multicomponent Systems

Ridwan Sakidja, Professor, Physics Astronomy and Materials Sci., Missouri State University, Springfield

 

2007

2008

2009

An Overview of the Library Resources for the Students of Chemistry

Chris Jocius, Reference Library, MS&T

 

Microalgase-Based Bioremediation and Biofuels

Paul K. Nam, Dept. of Chem., MS&T

Abstract: Aquatic microalgae are photosynthetic microorganisms that have great potential to be the solution to growing energy and environmental challenges, as more practical and environmentally benign methods for renewable biofuel production, carbon dioxide sequestration and wastewater remediation. Multidisciplinary collaborative research is conducted to develop economical and environmentally-sustainable technologies for microalgae that utilize carbon dioxide and wastewater as nutrient sources and yield algal biomass that can be converted to biofuels. Unicellular microalgae are fast growing and efficient converters of solar energy and carbon dioxide, thereby producing many times the biomass per unit area of land when compared to terrestrial plants. We have established a collection of microalgae species, specifically native species that adapt well to local environmental conditions and can resist the invasion by undesirable species. Cultivation conditions for the maximum production of algal biomass and target biochemicals have been investigated. Efficient techniques for harvesting and dewatering algal biomass are developed in the lab and tested for the field application. A pilot open-pond cultivation system that can utilize carbon dioxide in the flue gas generated from a coal-fired power plant is constructed for the demonstration of large-scale (10,000 gallons) algae cultivation and harvesting processes. Supercritical catalyst-free transesterification reaction is evaluated for the efficient production of biodiesel from oil-bearing crops including microalgae. Improved methods for pretreatment and hydrolysis of microalgae as cellulosic ethanol feedstock are also being investigated. Ultimately, these innovations will contribute in the development of an integrated self-supported system/process that incorporates the microalgae cultivation process with bio-refinery that is dedicated to algae-based biofuels and products. 

 

Assemblies of Nanoparticles as 3D Scaffols for New Materials: from Mechanically Strong Polymer Crosslinked Aerogels to Porous Iron and Silicon Carbide

Nicholas Leventis, Dept. of Chem., MS&T

Abstract: Monolithic, low-density 3-D assemblies of nanoparticles, known as aerogels, are pursued for unique properties above and beyond those of their individual building blocks. Specifically, since those materials are characterized by large internal void space (>80% v/v) they demonstrate low thermal conductivity, low dielectric constants and high acoustic impedance. The most common type of aerogels are based on silica and they are environmentally sensitive (hydrophilic, fragile) limiting their practical applications in certain nuclear reactors as Cherenkov radiation detectors, as devices for capture of hypervelocity particles in space (NASA’s Stardust Program), and as thermal insulation of electronic boxes aboard planetary vehicles such as the Sojourner Rover on Mars (1997), and the two Mars Exploration Rovers Spirit and Opportunity (2004).

The fragility problem of silica aerogels is traced to well-defined weak points in their skeletal framework, the interparticle necks.  Using the surface functionality of the inorganic nanoparticles as a focal point, we have directed attachment of a conformal polymer coating over the entire skeletal framework, bridging the nanoparticles and rendering all necks wider [1,2]. Thus, although the bulk density may increase by a factor of 3 (still an ultra-lightweight material), the mesoporosity (pores in the range 2-50 nm) remains almost unchanged, while the strength of the material can increase by up to a factor of 300 above the strength of the underlying inorganic framework. In that regard, polymer crosslinked aerogels may combine a multiple of the specific compressive strength of carbon fiber reinforced composites with the thermal conductivity of styrofoam. The crosslinked aerogel technology has been demonstrated with several different polymers such as polyurethanes/polyureas, epoxies and polyolefins, while ~35 different metal and semimetal sol-gel oxides from the periodic table have been crosslinked successfully yielding a combination of structural, magnetic and optical properties.  Currently polymer crosslinked aerogels are evaluated as starting materials for the carbothermal synthesis of carbide and pure metal aerogels [3,4], while applications being explored include thermal and acoustic insulation, ballistic protection (armor), membranes for use in separation technology, dielectrics and supports for catalysts.

Energy Conservation Awareness Activities in Schrenk Hall

Sasidhar Siddabattuni, Dept. of Chem., MS&T

 

Transparent Conductors: From Basic Principles to Controllable Properties

Dr. Julia Medvedeva, Dept. of Physics, MS&T

Abstract: Many optoelectronic technologies, including photovoltaic cells, flat panel displays, organic light-emitting diodes and energy-efficient windows, require materials which possess a unique combination of two seemingly contradictory properties - optical transparency and electrical conductivity. Such a combination is attained in a few oxides - doped In2O3, ZnO, CdO and SnO2.

Here, we summarize the key electronic features essential for achieving good carrier transport while maintaining sufficient optical transmission in a typical transparent conducting oxide (TCO). The role of the following factors governing the electrical and optical properties is discussed: (i) the local and long-range crystal symmetry; (ii) the electronic configuration of the cations; and (iii) the carrier generation mechanism employed. The results not only provide microscopic insight into the underlying phenomena in conventional TCOs but also serve as a solid foundation for further search for efficient transparent conductors beyond those traditionally employed.

 

 

Investigation of Pharmaceuticals and Personal Care Products in Missouri Natural and Drinking Water Using LC-MS/MS

Chuan Wang, Dept. of Chem., MS&T

Abstract: The trace amount of pharmaceuticals and personal care products (PPCPs) in natural waters has dramatic effects on the aquatic environment. Furthermore, the PPCPs in surface water may also have possible health impacts on humans because surface water is used as drinking water after treatment by water treatment facilities.  Therefore, the analysis of pharmaceuticals and personal care products in natural and treated waters become very important to provide information about the removal of PPCPs in drinking water and waste water treatment processes.

In this presentation, a comprehensive method has been developed and validated in two different water matrix for the analysis of sixteen important PPCPs by a single solid phase extraction (SPE) of 0.25 L water sample followed by analysis using liquid chromatography coupled with tandem mass spectrometry. Sixteen compounds which representing antibiotics, hormones, analgesics, stimulants, antiepileptic and X-ray contrast media were analyzed in both untreated and treated drinking waters. Water samples were collected from 34 different water treatment facilities across Missouri in both winter and summer seasons. The method detection limit for these compounds ranged from 1 to 20 ng/L. The details about method development, method validation, occurrence data, quality assurance and the trend of the PPCPs in different types of water and seasons will be discussed.  In addition, the treatability of PPCPs by free chlorine will also be presented.

 

Synthesis and Fluoride Anion Binding Studies of Fluorinated Boron-Based Anion Receptors

Nanditha G. Nair, Dept. of Chem., MS&T

Abstract: A series of fluorinated boron based anion receptors were synthesized and their fluoride ion binding was studied using spectroscopic techniques. Structures of the fluorinated boroxines, tris(2,6-difluorophenyl)-boroxin (DF), tris(2,4,6-trifluorophenyl)boroxin (TF), and tris(pentafluorophenyl)boroxin (PF), and boroxin-fluoride complexes have been confirmed by comparing their 19F and 11B NMR chemical shifts with those obtained by DFT-GIAO method and also by mass spectroscopic studies.

The stoichiometry of the fluoride anion binding to these boroxines has been shown to be 1:1 using 19F NMR, UV-vis spectroscopy. Further confirmation was obtained by mass spectroscopic studies for DF. UV-vis spectroscopic studies show the co-existence of more than one complex, in addition to 1:1 complex, for perfluorinated boroxin, PF. DFT calculations (B3LYP/6-311G**) show that the fluoride ion complex of DF prefers unsymmetrical, covalently bound structure over the symmetrically bridged species  by 12.5 kcal/mol.

Analysis and Occurrence of Disinfection By-Products in Fresh and Salt Water

Honglan Shi, Dept. of Chem., MS&T

Abstract: Haloacetic acids (HAAs), trihalomethanes (THMs), and bromate are toxic water disinfection by-products (DBPs) that US Environmental Protection Agency regulated in drinking water.  Iodoacetic acids, halonitromethanes (HNMs) are the emerging DBPs that have been recently found in the disinfected drinking waters with much higher toxicity than the regulated DBPs at the same concentrations.  This seminar will present our new rapid and sensitive methods [1] for the analysis of these DBPs, the occurrence screening study of the DPBs in 34 Missouri drinking water treatment systems, occurrence and formation studies of these DBPs in seawater/saltwater based aquaria in the SeaWorld Parks.  Several types of State-of-the-Arts analytical instrumentations were used to perform the experiments, including ion chromatography-inductively couple plasma/mass spectrometry (IC-ICP/MS), liquid-liquid extraction followed by gas chromatography-mass spectrometry (LLE-GC-MS), and solid phase microextraction (SPME)-GC-MS.  The highly cytotoxic and genotoxic emerging HNMs were detected in most of the Missouri drinking waters with the concentrations in the range from non-detectable to 6.71 µg/L, within the range of the national wide screening studies (up to 10 µg/L).  All of these DBPs were formed in the aquaria of SeaWorld Parks at much higher concentrations than those in the drinking water.  These DBPs are not only harmful to the SeaWorld Park workers and marine animals; they may also be the major causes of the eye irritation problems in the SeaWorld Park aquaria [2].

Determination and Quantification of 2-Hydroxy(Methylthio)4-Butanoic Acid and Pantothenic Acid in Bovine Serum and Sea Water Using RPLC, ESI-MS, LC-MS, and the Tandem MSDetoxification of Jatropha Curcas Oil and Meal: Characterization and Quantification of Phorbol Esters a Toxic Component of Jatropha Curcas

Balaji Viswanathan, Dept. of Chem., MS&T

 

Mesoscopic Physics of Photons: Particle Versus Wave Trasport Through Random Media

Dr. Alexey Yamilov, Dept. of Physics, MS&T

Abstract: The term mesoscopic physics refers to a wide range of quantum (or, more precisely, interference) phenomena which occur in solids between the macroscopic and microscopic size. Quantum or not, the interferencephenomena are common to waves of any nature, including the electromagnetic waves. I will explore the similarities and differences between mesoscopic electronic transport and  the light propagation in disordered media. In particular, I will discuss an exciting possibility of coherent amplification of photons which adds a new dimension to the fundamental study of mesoscopic transport and leads to a new physical phenomenon - random lasing.

 

 

Traditional and Non-traditional Chemistry Careers

Lisa Balbes, ACS Career Personnel

Abstract: A chemistry background prepares you for much more than just a laboratory career. The broad science education, analytical thinking, research methods, and other skills learned are of value to a wide variety of types of employers, and essential for a plethora of types of positions. By understanding your own personal values and interests, you can make informed decisions about what career paths to explore, and identify positions that match your needs. This talk will discuss a  variety of traditional and nontraditional careers for chemists, including positions in industry, academia and government,  chemical information, patent work, technical writing, education, human resources, sales and marketing, and much more. We will discuss typical tasks, education or training requirements, and personal characteristics that make for a successful career in each field, illustrated with specific examples. Valuable tips and advice about planning career transitions will also be provided.

 

Dynamics of Polymers at Interfaces using TMDSC and Deuterium NMR

Boonta Hetayothin, Dept. of Chem., MS&T

Abstract: The effect of molecular mass on the adsorption of poly(methyl methacrylate) (PMMA) on silica was determined by using temperature-modulated differential scanning calorimetry (TMDSC). A two-component model, based on loosely-bound polymer with a glass transition temperature (Tg) similar to that of bulk polymer and more tightly-bound polymer with a Tg higher than that of the loosely bound polymer, was used to interpret the thermograms. PMMA (with a high and medium molecular masses of 450 kDa and 85 kDa, respectively) had similar amounts of tightly bound polymer (approximately 0.78 mg/m2) adsorbed on the surface of silica with a corresponding thickness of about 0.65 nm.The low molecular mass, 32 kDa PMMA, had a smaller amount of tightly bound polymer (about 0.48 mg/ m2) adsorbed on the silica surfaces, corresponding to a thickness of 0.40 nm. The ratios of heat capacity increments of the loosely bound and tightly bound components (ΔCpA/ΔCpB) in the glass transition regions, indicating the relative mobility of the two components, were also estimated.  

A study of the effect of functional groups on adsorbed polymers, such as poly(methyl methacrylate) (PMMA), poly(vinyl acetate) (PVAc) and poly(methyl acrylate) (PMA) on silica surfaces, was also determined using TMDSC. In this study, polymers of high molecular mass (200-450 kDa) were used. The results showed little difference in the amount of the tightly bound component for adsorbed PMMA and PVAc on silica (0.78 mg/m2), while the amount of the tightly bound in adsorbed PMA on silica showed less, but not significantly different (0.72 mg/m2) amounts.  These tightly bound amounts of polymers adsorbed on the silica surfaces corresponded to the thicknesses of about 0.65 nm for PMMA and PVAc and 0.60 nm for PMA.  

The dynamic behavior of a plasticizer that affects bulk and adsorbed PVAc on silica was also studied using deuterium NMR (2H NMR). This study probed the effect of plasticizer on small adsorbed amounts of polymer (PVAc) on silica (approximately 0.8 mg polymer/m2silica). The deuterated plasticizer, dipropylene glycol dibenzoate (DPGDB-d10), was synthesized and used as a plasticizer for PVAc. Bulk PVAc and adsorbed PVAc on silica were prepared with approximately 10% and 25% plasticizer and used for this study. The changes of the lineshape of 2H NMR spectra suggested that, as the temperature increased the motion of the polymer segments also increased, and was even more pronounced in the presence of plasticizer. Additionally, the relaxation times of both pure deuterated plasticizer (DPGDB-d10) and plasticized bulk PVAc were observed.

 

2010

Plagiarism: Using Sources Responsibly

Daniel Reardon, Assistant Director, Writing Center, MS&T

Abstract: Integrating sources logically and responsibly is the first order of professional research for all scientists and technologists.  First, in order to do research, we must thoroughly understand work in our own fields; that work will inform, guide, and direct our own.  Researching the ideas of others has become more and more difficult in our present age, however.  In our information fluid age, when vast amounts of data are easily accessible and quickly changed, we have now, more than ever, a moral and ethical responsibility to honestly and properly acknowledge the ideas of others that have influenced our own.  It is all too easy, however, to copy, whether deliberately or unintentionally, ideas or portions of text without properly citing the sources of this information.  This type of copying—plagiarism—demonstrates incompetence. If we fail to record our sources and then later forget that we used those sources, we are still liable and open to the charge of theft of intellectual property.  By learning to properly and at all times, regardless of medium, record where we obtain ideas—whether we use them or not—we will maintain professional integrity with everything we write.  This presentation will offer several key principles and strategies for responsible research documentation and plagiarism avoidance.

 

Repair of the Flawed Introduction of Chemical Potential into Thermodynamics

Gary L. Bertrand, Dept. of Chem., MS&T

 

Investigating Antioxidant Chelation for the Treatment of Lead Poisioning

Weiqing Chen, Dept. of Biological Sciences, East China Normal University, Shanghai, China

Abstract: The toxic effects of lead have been manifested as inducements of imbalance between pro-oxidant and antioxidant homeostasis and high affinities for thiol groups in the functional proteins.  Prior in vivo studies on the treatment of lead poisoning using EDTA, N-acetylcysteine (NAC) and N-acetylcysteine amide (NACA) as chelators showed differences in their ability to decrease both Pb(II) levels and oxidative stress.  This present study, performed in vitro, was undertaken to further delineate their chelating abilities.  Pb-antioxidant complexations were performed at 0-10° C, dissolving antioxidant and Pb acetate in deionized, distilled water.  UV-vis spectroscopy was used to investigate the binding interactions of Pb with these antioxidants in solution while X-ray photoelectron spectroscopy (XPS) was used to quantify the amount of Pb bound to the antioxidant.  Job’s Method plots obtained from UV data revealed 1:1, 1:2.5 and 1:1.5 stoichiometric ratios for EDTA:Pb, NAC:Pb and NACA:Pb coordination, respectively.  Deconvolution of the XPS Pb 4f orbitals indicated a greater amount of covalently bound Pb(II) accompanying Pb-NACA complexation as compared to the formation of Pb-NAC and Pb-EDTA.  In comparing Pb coordination to NAC and NACA, the increase in the amount of Pb bound to the antioxidant in the XPS data correlated with differences in their point of zero charge (PZC) values.  Insights into the binding of Pb to this series of antioxidants will be discussed.

 

NMR Investigations of Hydrothermal Liquefaction of Biomass

Wenjia Zhang, Dept. of Chem., MS&T

Abstract: Hydrothermal liquefaction of cellulosic biomass to synthetic fuel has gained considerable attention for it is conducted in aqueous solution at temperatures and pressures significantly lower compared with biomass pyrolysis or gasification. To elucidate the mechanisms of hydrothermal carbonization, the hydrothermal reaction of D-glucose as a moel substrate was examined using quantitative analysis of 1H, 13C and two-dimensional NMR. For the investigation, we have developed and optimized a new presaturation sequence (EXCEPT = EXponentially Converging Eradication Pulse Train) to suppress the water 1HNMR signal.The studies confirm that D-glucose is first dehydrated in aqueous solutions to 5-hydroxymethylfurfural (5-HMF) and subsequently re-hydrated to 4-oxopentanoic acid (levulinic acid). The invesigation also reveals the formation of other compounds, some of which are yet unidentified. 

 

An Approach to Binary Radiation Therapy Mediated by Neutron Capture

M. Frederick Hawthorne, University of Missouri

 

 

An Overview of Environmental Regulations for the Chemist

Dennis L. Whitney, Environmental Engineer, American Airlines, Retired

Abstract: Since the National Environmental Policy Act was passed and signed by President Richard Nixon in 1969, a large number of environmental laws have been enacted. The major laws that affect the chemical community are the Resource Conservation and Recovery Act, RCRA, the Clean Water Act, the Comprehensive Environmental Response Comprehensive Liability Act, CERCLA, also know as the Superfund Act, and the Superfund Amendments and Reauthorization Act know as SARA Title III, and the Clean Air Act. There have also been other laws that regulate petroleum spills, asbestos management, toxic chemicals regulated by the Toxic Substances Control Act, the management of nuclear (radioactive) waste, the transportation of hazardous wastes, and the cleanup of hazardous waste spills. There are also regulations concerning the safety of chemical workers published by the Occupational Safety and Health Administration.

Chemical students and professionals at all levels should be aware of the nature of these laws because, in many cases, they may be held personally, and sometimes criminally, liable for damages that may occur due to non-compliance.

 

 

Oxidative Stress in HIV-Associated Dementia

Dr. Atrayee Banerjee, Dept. of Chem., MS&T

Abstract: An increased risk of HIV-1 associated dementia (HAD) has been observed in patients abusing methamphetamine (METH). Since both HIV viral proteins (gp120, Tat) and METH induce oxidative stress, drug abusing patients are at a greater risk of oxidative stress-induced damage. The objective of this study was to determine if N-acetylcysteine amide (NACA) protects the blood brain barrier (BBB) from oxidative stress-induced damage in animals exposed to gp120, Tat and METH. To study this, CD-1 mice pre-treated with NACA/saline, received injections of gp120, Tat, gp120 + Tat or saline for 5 days, followed by three injections of METH/saline on the fifth day, and sacrificed 24 h after the final injection. Various oxidative stress parameters were measured, and animals treated with gp120+Tat+Meth were found to be the most challenged group, as indicated by their GSH and MDA levels. Treatment with NACA significantly rescued the animals from oxidative stress. Further, NACA-treated animals had significantly higher expression of tight junction (TJ) proteins and BBB permeability as compared to the group treated with gp120+Tat+METH alone, indicating that NACA can protect the BBB from oxidative stress-induced damage in gp120, Tat and METH exposed animals, and thus could be a viable therapeutic option for patients with HAD.         

HAART Drugs Induce Cytotoxicity Via Oxidative Stress and Mitochondrial Dysfunction in Blood-Brain Barrier Cells

Kalyan Manda, Dept. of Chem., MS&T

Abstract: The blood–brain barrier (BBB) is a diffusion barrier which selectively regulates the flow of molecules from blood to the brain.  Dysfunction of the BBB that was observed in the course of HIV infection has been confirmed by variety of pathological studies. Alterations in the barrier function of the brains endothelium have also been implicated in HIV-1-associated neurocognitive disorders (HAND) as well as other neurological disorders like multiple sclerosis and Alzheimer’s disease.

The era of highly active antiretroviral therapy (HAART) has led to a considerable decline in new cases of a severe form of HAND, called HIV-1-associated dementia (HAD). However there has been a significant increase in the number of existing cases with a milder form of HAND.  In view of these developments, we hypothesized that HAART drugs may induce oxidative stress in the BBB thereby exacerbating the condition. Exposure of human blood brain endothelial cells (hCMEC/D3) to a combination of two HAART drugs, Zidovudine (3’-azido-2’,3’-deoxythymidine; AZT) and indinavir (IDV) significantly reduced viability after a 72 hr treatment, in a dose-dependent manner. Oxidative stress parameters like glutathione (GSH) and malondialdehyde (MDA) were found to be significantly altered after exposure. Loss of mitochondrial membrane potential (Ψm) assessed using fluorescent microscopy and decreased ATP levels revealed that cytoxicity was mediated through mitochondrial dysfunction. Permeability of dextran and measurement of trans-endothelial electrical resistance (TEER) across a monolayer of cells indicated that the integrity of BBB was compromised after the treatment. The results from our studies suggest that treatment with AZT + IDV may oxidatively challenge the BBB during antiretroviral therapy via mitochondrial dysfunction, thereby altering the functionality of this layer.

Control and Design of Structural Variations in Nickel Trimer Complexes

Carla Schmiesing, Dept. of Chem., MS&T

 

Electrodeposition of Superlattices in the Magnetite/Zinc Ferrite System which Exhibit Resistance Switching

Rakesh V. Gudavarthy, Dept. of Chem., MS&T

Abstract: In this work, both defect-chemistry and compositional superlattices in the Fe3O4/ZnFe2O4 system are electrodeposited. There is interest in depositing thin films and superlattices based on Fe3O4 because the conducting cubic phase transforms to the insulating monoclinic phase below the Verwey transition at 120 K, making it a good candidate for resistance random access memory (RRAM) devices. For such RRAM devices, it is often necessary to have nanophase material. Electrodeposition can produce such nanophase material with precise control of composition and morphology by simply controlling the temperature, pH and overpotential. In ZnFe2O4, the Zn(II) substitutes for Fe(II) producing a material that is antiferromagnetic below the Néel temperature.

 Films of Fe3O4 are electrodeposited with stoichiometries that depend on the applied potential. We prepare the films by electrochemical reduction of a Fe(III)-TEA (triethanolamine) complex at 80 oC in strongly alkaline solution. Because of the electrochemical-chemical nature of the deposition mechanism, it is possible to control the composition of film through the applied overpotential. At low overpotentials at which j = 0, the surface concentration of Fe(TEA)3+ should be equal to the bulk concentration, whereas at high overpotential at which j = jL the surface concentration of Fe(TEA)3+ should approach zero. Hence the material should have an excess of Fe3+ at low overpotential and an excess of Fe2+at high overpotential. X-ray diffraction, Mössbauer and magnetic studies have confirmed that stoichiometric magnetite can be produced at -1.065 V vs. Ag/AgCl. Superlattices of the material are electrodeposited by pulsing the applied potential between -1.01 and -1.065 V vs. Ag/AgCl. Compositional superlattices can be produced by adding Zn(II) to the deposition bath.

 We have shown that epitaxial magnetite films and superlattices on single crystal Au(111) substrate exhibit resistance switching.1 A stoichiometric Fe3O4 on Au(111) produced at -1.065 V has only one resistance switch. On the other hand, the superlattices on Au(111) have multistate resistance switching and a unique negative differential resistance feature.

 

Toward Higher Energy Density Dielectrics Through Nanocomposites

Sasidhar V. Siddabattuni, Dept. of Chem., MS&T

Abstract: Dielectric materials that are capable of storing large amounts of electric energy are desirable for many electronic and electric systems.  Since the electric energy density in a linear dielectric material is equal to kEb2/2, where k is the dielectric constant (e’) of the material and Eb is the dielectric breakdown strength, both large e’ and high Eb are required for large electric energy storage.  While ceramic materials like barium titanate usually have large e’, they are limited by their relatively small Eb, poor processability and mechanical properties.  On the other hand, polymers usually have higher Eb and excellent mechanical properties and processability but suffer from a smaller e’.  A higher Eb is more beneficial to enhance energy density than a proportional increase in e’.  Thus, numerous efforts have been ongoing to combine polymers of high Ebwith nanoparticles of high e’ with the desire to enhance the dielectric film energy storage density through nanocomposites.  In this work, we strengthen the nanocomposite filler-polymer interface through the use of bifunctional reagent, 2-aminoethyl dihydrogen phosphate (AEP), to modify the surface of titania and barium titanate.  The AEP filler surface can then covalently react with polymer matrix during cure to achieve a strong, covalent interface when used with thermosetting composites, such as an epoxy polymer matrix.  Results show that interfacial covalent bonding is an effective approach to increase the electrical resistance of a polymer-particle composite to charge flow and dielectric breakdown.  Interface-modified composites retain the glass transition temperature of pure polymer, reduce Maxwell-Wagner relaxation of the polymer-particle composite, and have a reduced sensitivity to dielectric breakdown compared to composites with adsorbed interfaces. 

 

The Sexuality of the Chemistry of Explosives and Explosives at S&T or Why Things Go Boom... How Chemistry Plays In Explosives

Prof. Paul Worsey, Dept. of Mining and Nuclear Engineering, MS&T

Abstract: A humorous take on explosives chemistry and the perhaps the reason why it should be left in the hands of Chemists. This will be followed by a brief condensed history of the chemistry of explosives to present, a briefing on where 99% of explosives are used, and what the explosives program is up to at Missouri S&T.

Job Search Techniques & Interviewing

Edna M. Grover-Bisker, Associate Director, Career Opportunities Center, MS&T

 

Novel Imaging Platform for Deciphering Motions in Living Cells

Prof. Ning Fang, Dept. of Chem., Iowa State University

Abstract: Characteristic translational and rotational motions of bimolecular and nanoparticles are fundamental to most chemical and biological phenomena. Translational motion can be readily revealed by a variety of single-particle/molecule tracking methods. However, rotational motion is much more difficult to resolve due to technical limitations. The prominent examples of lacking knowledge on rotational motion are endocytosis and intracellular transport in live cells. The current understanding of rotational motion was acquired mostly in vitro using methods based either on fluorescence polarization or on super-localization of translational probes. Resolving dynamic rotational motion in living cells or other complex environments is still challenging. We developed novel optical imaging tools, based on plasmonic nanoparticle probes and differential interference contrast (DIC) microscopy, to visualize and decipher?single-nanoparticle/molecule translational and rotational motion in complex environments and address outstanding questions in chemical and biological systems that were previously unattainable. Our current efforts are focused on deciphering rotational motions involved in receptor-mediated endocytosis, intracellular transport, and rotational diffusion on the cell membrane.

 

Oxidation of Zirconium Diboride Based Ultra-High Temperature Ceramics

William G. Fahrenholtz and Gregory E. Hilmas, Dept. of Material Science and Engineering, MS&T

Abstract: Oxidation behavior of zirconium diboride based ultra-high temperature ceramics will be discussed. When exposed to oxidizing environments, ZrB2 undergoes stoichiometric oxidation forming ZrO2 and B2O3. At elevated temperatures, B2O3 volatilizes, leaving a layer of porous ZrO2, which is not protective and allows rapid oxidation of the underlying ceramic. The most common strategy for improving oxidation resistance is to add silicon containing compounds such as SiC or MoSi2, which results in formation of a SiO2 layer that provides improved oxidation protection at intermediate temperatures. This presentation will focus on key aspects of the response of ZrB2-based ceramics to oxidizing environments. Cross sections of oxidized specimens will be characterized to determine the composition and thickness of reaction layers. Thermodynamic tools will be used to interpret the evolution of structure during oxidation. In addition, the addition of tungsten will be discussed as an alternative to silica formers for improving oxidation protection.

Smelting in the Age of Nano Metal Aerogels

Naveen K. Chandrasekaran, Dept. of Chem., MS&T

The History of the Chemistry Set

Dennis L. Whitney, Environmental Engineer, American Airlines, Retired

Abstract: Toy chemistry sets have been a favorite and useful tool in chemical education since they were first introduced by Mr. Gilbert and Mr. Porter in the 1920s. Unfortunately, they are now no longer widely available.  A short discussion will be presented as to both how the chemistry set evolved from mining tools and the magic sets that were popular in the last century and the cause of their recent decline as a popular toy for children. Some vintage chemistry sets will be displayed.

Surface Plasmon Resonance Imaging

Dr. Yi Chen, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China

Abstract: Surface plasmon resonance imaging (SPRi) was developed based on a phenomenon of surface plasmon wave which was first observed in 1902 [1] but elucidated in theory half a century later, in 1959 [2]. SPRi appeared for the first time in 1987 [3]. However, it has also been delayed to develop into an analytical method, though, it is inherently a high throughput technique suitable for study of intact biological macromolecues [4]. We have worked on SPRi since 1997, starting from the design and fabrication of SPRi systems due to the unavailability of a commercial instrument at that time. With laboratory-fabricated systems controlled also with laboratory-edited image workstations, color or grey images of chemical microdots spotted on gold sensing surfaces were easily imaged at a density of up to about 5000 dots/cm2. Methods were then explored for high throughput analysis of various samples and chemical or biochemical processes. Some examples will be discussed like protein denaturing, enzymatic digesting or decomposing, and molecular recognizing events. These works suggest that SPRi could become a novel high throughput platform for characterization and determination of intact biological molecules including not only proteins but also DNA, saccharides and many glycol-conjugates. Further studies are however needed and waiting for conduction.

Compliance with Environmental Regulations

Dr. Alice Beechner Reeves, President & Principal, Paragon Business Solutions, Inc. 

 

Bogan with Poems on Science

Prof. James J. Bogan, Curators' Teaching Professor of Art History and Film, MS&T

Abstract: Professor Bogan will present some of his poems that have been inspired by science and engineering. In addition he will screen his most recent short film, MAN vs. TREE, to illustrate how the experimental method can be used in documentary film production.

 

Chemistry in Shakespeare

Prof. Nicholas W. Knight, Dept. of English, MS&T

Abstract: By using references found in Shakespeare’s 30 plays, written between 1588 and 1610, we can discern his awareness of the current developments in the sciences of chemistry, biochemistry, medicine, astronomy, physics, geography, geology, and psychology. He explicitly refers to both the much earlier work of Galen (~130–~200), and his near-contemporary Paracelsus (1490–1541), in All’s Well that Ends Well, moving from alchemy and astrology to medicine. In Romeo and Juliet, he deals with drugs and poisons. Not only are these plays evidence of Shakespeare’s knowledge of the scientific developments of his time, but a close analysis of Documented Polypharmacology in Treating Diseases a treatise by his son-in-law, John Hall, reveals, for his period of time, an advanced knowledge of the methodology and practice of medicine, both in Shakespeare’s own family and in the nobility in Shakespeare’s England. 

Electrodeposition of Metal Oxides

Niharika Burla, Dept. of Chem., MS&T

 

Aerogels and Films through Free-Radical Chemistry

Mr. Anand Sadekar, Dept. of Chem., MS&T

 

The Role of Materials in the Development of Mankind

Dr. Wayne Huebner, Dept. of Materials Science and Engineering, MS&T

Abstract: Advances in the development of man can be traced to his mastery of the world of materials around him.   This presentation will initially focus on the ages of man from the Stone Age through today's Nano/Bio Age, with particular emphasis on the evolution of our understanding of structure-processing-property relation-ships. Then I will present many examples of leading-edge materials research at S&T.

 

The Heat Capacity of Sodium Atoms as an Ideal Gas and a Real Gas

Dr. Louis Biolsi, Dept. of Chem., MS&T

 Abstract: The ideal gas heat capacity of sodium atoms is calculated to high temperatures. At higher temperatures, the increasing size of the atoms as a con-sequence of the population of highly excited electronic energy levels must be considered or the heat capacity becomes very large.

The sodium atoms are also considered to be a real gas that obeys the virial equation of state. The first non-ideal term in the virial expansion is evaluated. This involves the second virial coefficient which depends on the interaction between two sodium atoms. Contributions to the heat capacity of sodium atoms from the virial coefficients associated with the lowest ten states of the sodium dimer are considered.

 

 

2011

The Characterization of Ultrafine Particulate Matter from Combustion Processes

Dr. Philip D. Whitefield, Dept. of Chem., MS&T

 

 

 

Treatability of Envrionmental Contaminants and Removal of Disinfection By-Products in Drinking Water Using LC-MS/MS

Yinfa Ma, Dept. of Chem., MS&T

Abstract:  Environmental contaminants in natural and drinking waters, such as pesticides, herbicides and pharmaceuticals and personal care products (PPCPs), may exert possible health impacts on humans In addition, many disinfection byproducts (DBPs), such as  N-nitrosamines, halonitromethanes (HNMs), could also exist in drinking water after water treatment processes at water treatment facilities. Therefore, efficient treatment and removal of these emerging contaminants and DBPs in natural and treated waters become an important issue for environmental researchers so to provide safe drinking waters for human and animals.

In our recent study, chemical and physical methods for removal of selected PPCPs and DBPs in natural and drinking waters have been investigated by using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and other analytical techniques. The details on method development, quality control/assurance, removal efficiency, and potential solutions for a clean drinking water will be discussed.  

 

 

 

Organfluorine Chemistry in the Design of Cell Cycle Inhibitors

Dr. V. Prakash Reddy, Dept. of Chem., MS&T

Abstract:  In view of the unique applications of organofluorine compounds in bioorganic and medicinal chemistry, a series of novel purine-based fluoroaryl triazoles have been synthesized using the Cu(I) catalyzed 1,3-dipolar cycloadditions, and assayed for their potency in cell cycle inhibition using Ab cultures.  Some of these triazole derivatives are found to have comparable effect as that of Roscovitine, and Flavopiridol, the widely used cyclin-dependent kinase (CDK) inhibitors currently under clinical trials, in cell cycle suppression. The beneficial effects of these triazole based purine derivatives on the Amyloid-beta (Ab) induced neurotoxicity is significant, and thus they would have potential therapeutic applications. General synthetic methodologies for organofluorine compounds will also be discussed.

Optimization of the Response Times in Photorefractive Polymeric Composites through the Inclusion of Semiconductor Nanocrystals

Jeffrey G. Winiarz, Dept. of Chem., MS&T

Abstract:  The phenomenon of photo refractivity, which involves the creation of a reversible hologram generated by the crossing of two coherent beams in an appropriate medium, can be realized in polymeric composite materials which simultaneously exhibit photoconductive and electro-optic properties. The nanocomposite approach offers opportunities to produce high performance and relatively low cost optoelectronic media, suitable for many applications. Especially promising are nanocomposites of polymers and inorganic semiconductor nanocrystals commonly known as quantum dots. Initially, experiments focused on the optical absorption properties of quantum dots and their dependence on composition and size. The broad tunability of the spectral response and increased photo-charge generation efficiency were particularly interesting with respect to photorefractive composites. More recently, however, time-of-flight experiments have revealed that the mere inclusion of semiconductor nanocrystals significantly enhances the mobility of charge carriers in polymeric composites. This enhanced mobility translates into an improved response time; an issue which has plagued this class of materials since their inception and has precluded their use in many practical applications. This seminar will present experimental evidence confirming that through judicious selection of an appropriate semiconductor material, the loading content of the photosensitizing nanocrystals can be increased while avoiding detrimental effects such as substantial optical absorption losses. Through increased loading, the enhanced charge-carrier mobility associated with the nanocrystals can be more fully exploited leading to improved response times. In addition, data will be presented which demonstrates the ability to achieve unprecedented response-times through enhanced charge-carrier mobility via the inclusion of semiconductor nanocrystals in more traditionally organically photosensitized photorefractive composites.

A General Scheme for Representing Potential Energy Suraces for Multi-channel Reactions

Dr. Richard Dawes, Dept. of Chem., MS&T

Abstract: The potential energy surface (PES) is central to how chemists think about the structure and dynamics of molecular systems, in terms of minima or asymptotes connected by paths across landscapes and over energetic barriers.  The concept of an adiabatic energy hypersurface is a result of the Born-Oppenheimer approximation and is usually sufficiently accurate even for high-resolution spectroscopic applications. When necessary, most treatments of non-adiabatic dynamics begin with a set of (coupled) adiabatic electronic states, making the potential energy surface ubiquitous to theoretical chemistry.

      I will describe some methods used to compute accurate molecular electronic energies and fit them into analytic functional forms (PESs). A strategy for multichannel reactions and representative results from studies of spectroscopy and dynamics will be shown. 

Topics in Nuclear Magnetic Resonance Spectroscopy and Imaging

Dr. Rex E. Gerald II, Argonne National Laboratory, Dept. of Chem., MS&T

 

History, Politics, Hope for the Future- Energy?

Dr. Jack Magruder, Prof. of Chemical Education, President of A.T. Still University of Health Sciences

 

Further Materials Research at MS&T

Dr. Wayne Huebner, Dept. of Material Sciences and Engineering, MS&T

Abstract: Advances in the development of man can be traced to his mastery of the world of materials around him.  This presentation will initially focus on the ages of man from the Stone Age through today's Nano/Bio Age, with particular emphasis on the evolution of our understanding of structure-processing-property relation-ships. Then I will present many examples of leading-edge materials research at S&T.

 

In vivo Inhibition of L-Buthionine-(S,R)-Sulfoximine(BSO)-Induced Cataracts by a Novel Antioxidant,

N-acetylcysteine Amide

Joshua W. Carey, Dept. of Chem., MS&T

Abstract: Cataracts are the most common cause of treatable blindness worldwide. It has been shown that cataracts likely develop due to the effects of oxidative stress. Oxidative stress is caused by an imbalance between the production of reactive oxygen and a biological system's ability to readily detoxify the reactive intermediates or easily repair the resulting damage. A normal lens has several antioxidant enzymes and a high concentration of ascorbate and GSH that protect it from the damages of oxidative stress. The ability of the lens to resist oxidative damage decreases dramatically with the age related decrease in the production of GSH by the cell. GSH is an important thiol for protecting against GSH and maintaining the transparency of the lens. The effects of GSH on normal lens function can be studied by depleting the intercellular levels of GSH using L-Buthionine-(S,R)-sulfoximine (BSO). BSO is an inhibitor of γ-glutamyl-cysteine synthetase, which is known to deplete the levels of GSH both in vivo and in vitro. The role of GSH can be studied by inducing BSO generated cataracts in an animal model. When GSH levels are depleted the formation of a cataract occurs; however it has been suggested that by increasing the levels of antioxidants in the cell it is possible to prevent the formation of cataracts. Recent research using N-acetylcysteine amide, (NACA) a novel antioxidant, have led to the theory that it may be possible to reverse the effects of oxidative damage in low grade cataracts.

 

Inorganic Chemistry for the Mineral Collector

Dennis L. Whitney, Environmental Engineer, American Airlines, Retired

Abstract: The collection and classification of minerals may be either a hobby or a profession that involves the study of geology, mineralogy, and inorganic chemistry. The history of mineral collecting and the Old Dana, Strunz, and New Dana classification systems used to classify a systematic mineral collection will be discussed.

The assay of a mineral typically does not provide information about its systematic mineralogy, but rather provides only its bulk chemical composition in terms of its corresponding elemental oxides. The reasons for this unusual approach to reporting the composition of a mineral will be discussed. Exotic and unusual mineral specimens will be displayed and the processes involved in assembling a mineralogical study collection will be discussed.

Biomarkers for Noninvasive Early Cancer Detection

Sanjeewa Gamagedara, Dept. of Chem., MS&T

Abstract: Cancer is the second leading cause of death, accounting 13% of all deaths worldwide. Deaths from cancer are projected to continue rising, with an estimated 12 million deaths in 2030. Cancer develops rapidly and early diagnosis and treatment greatly improve the patient’s chances of survival. Biomarkers are good potential candidates for this early cancer diagnosis.

    Part I:Recently pteridines become a focal point of cancer screening research because certain pteidines levels have been shown to reflect the presence of cancers. This study analyzed eight pteridines; 6,7-dimethylpterin, 6-biopterin, D-(+)-neopterin, 6-hydroxymethylpterin, pterin, isoxanthopterin, xanthopterin and pterin-6-carboxylic acid using a house-built high-performance capillary electrophoresis with laser-induced fluorescence detection (HPCE-LIF). The levels of pteridines were reported as a ratio of pteridine to creatinine. Statistical hypothesis testing was conducted and P-values were calculated to analyze the data.

    Part II: Sarcosine and related matebolomic profiles recently drew a lot of attention because a debate regarding their possible role as potential clinical markers for prostate cancer. In this study, levels of sarcosine and related metabolites in 126 patients with genitourinary malignancies (63 prostate cancers & 63 bladder cancers) were analyzed using a validated LC/MS/MS method. Statistical hypothesis testing, Multivariate analysis of variance, correlation study, and principal component analysis were conducted to analyze the data. For prostate cancer these biomarker levels were compared in T1,T2 stages and Gleason scores <7, ≥7.  The detailed experimental conditions and results will be presented at the seminar.

 

Corrosion Coatings Based on Rare-Earth Oxide Inhibitors

Dr. Matt O'Keefe, Dept. of Material Sciences and Engineering, MS&T

 

The Art and Science of Microscopy

Clarissa Wisner, Electron Microscope Specialist, MS&T

 Abstract: 

In 1661, Henry Powers, wrote a poem “In Commendation of ye Microscope,”

 

"Of all the Inventions none there is Surpassed

the Noble Florentine's Dioptrick Glasses

For what a better, fitter guift could bee

in this World's Aged Luciosity.

To help our Blindnesse so as to devise

a paire of new & Artificial eyes,

by whose augmenting power wee

now see more than all the world Has euer donn Before."

 

This poem is still so true today, with all the innovations to the world of microscopy.  But not all work in microscopy is scientific in nature.  There is a growing industry that uses the microscope to enhance walls, textiles, pottery and other ordinary everyday things.  The merging of these two dissimilar words is not only exciting, but interesting as one follows the history of the science of microscopy to the pop culture art world.

We will take a journey from the beginning of the microscope in the 16th century to the present that will not only give historical facts but beautiful images to entice everyone to take up microscopy as a hobby!

 

Nanoscale Acrylate Unimolecule Micelles

Cynthia Riddles, Dept. of Chem., MS&T

 

General Laboratory Safety Training

Phyllis Lewis, Environmental Specialist, Environmental Health and Safety

Abstract: 

  • Hazardous Waste Management
    • Federal Regulation & University Policy
    • Types of waste handled by Environmental Health and Safety
      • Chemical, Bio-hazardous, Universal
    • Proper storage of wastes
    • Proper labeling of wastes
    • Filling out the waste pick-up request form
    • Fire Safety (10 minute video)
    • Spill Response 
  • Laboratory Safety
    • General laboratory housekeeping
    • Safety policies
    • Common hazards in the laboratory
      • Chemicals, Bio-hazards, Radiation, Compressed Gas Cylinders
    • Labeling & Storage
    • Chemical inventory:  Chemtrack
    • Personal Protective Equipment
    • Emergency Response

 

 

An Overview of the Library Resources for the Students of Chemistry

Christopher Jocius, Head of the Reference Department C.L. Wilson Library, MS&T

Abstract: An overview of the resources available for chemistry graduate students at the Missouri University of Science and Technology library will be presented. This will include how to access and use the ACS based Scifinder to search the chemical scientific literature. 

Organic/Inorganic Aerogels through Ring Opening Metathesis Polymerization

Dhairyashil Mohite, MS&T

Abstract: Aerogels are open-pore, low-density nanostructured solids with high surface areas, low thermal conductivities, low dielectric constants and high acoustic attenuation. The most common type, silica aerogels, are made by base-catalyzed gelation of tetramethylorthosilicate (TMOS) and consist of a self-assembled, 3D skeletal framework of silica nanoparticles. Despite their attractive bulk properties, these materials are extremely fragile, which limits their applications. Strength of aerogels can be increased by providing interparticle polymeric tethers which covalently connect the skeletal nanoparticles. These new, mechanically strong porous materials are referred to as polymer crosslinked aerogels. Organic aerogels on the other hand are derived solely from organic polymers, mainly based on resorcinol-formaldehyde (RF), melamine-formaldehyde (MF), and phenol-furfural (PF) resins. Other polymer-based aerogels reported include polyurethane/polyurea, polystyrene, polydicyclopentadiene, and lately polyimides.

     Part A: Strong Silica Aerogels Crosslinked with Polynorbornene via Ring Opening Metathesis Polymerization (ROMP) Crosslinking of silica aerogels is demonstrated by ring opening metathesis polymerization (ROMP) by providing the surface of silica particles with the norbornene functionality using a new nadimide derivative of 3-aminopropyltriethoxysilane (APTES). Norbornene monomer is introduced in the mesopores and a ROMP process is started using 2ndgeneration Grubbs’ catalyst at ambient temperature. The growing polymer engages norbornene moieties bound on the surface of 

silica forming a conformal coating of polynorbornene on the mesoporous surfaces throughout the entire skeletal framework. The amount of polymer incorporated in the mesoporous structure is controlled by the concentration of the monomer in the mesopores. Despite the increase in bulk density (up to 0.6-0.7 g cm-3), decrease in porosity (down to ~50% v/v), and decrease in surface area (down to ~150 m2 g-1), the materials remain mesoporous. The mechanical properties in terms of strength, modulus and the energy absorption capability relative to the native (non-crosslinked) counterparts are increased dramatically.

     Part B: Organic (Polyimide and Polydicyclopentadiene) Aerogels by ROMP Polyimide aerogels are synthesized by crosslinking through ROMP of a bisnadimide bifunctional monomer, bis-NAD, using a second generation Grubbs’ catalyst. Aerogels with different bulk densities (ranging from 0.13 to 0.66 g cm-3) were obtained by varying the monomer concentration in the sol (from 2.5% to 20% w/w). With increasing density, the interconnected nanoparticle structure changed from macro- to mesoporous and the percent ratio of the micropore area relative to the BET surface area decreased from 28% to 9%. bis-NAD aerogels demonstrate excellent mechanical strength and high specific energy absorptions.

     Synthesis of mechanically strong polydicyclopentadiene (pDCPD)-based organic aerogels is carried out through ROMP by reinforcing through post-gelation grafting with polymethylmethacrylate (PMMA) using free radical chemistry initiated with AIBN. Solid 13C CPMAS NMRs confirm the grafting of PMMA on pDCPD structure. Homogeneous aerogels with bulk density ~0.43 g cm-3 were obtained consisting of interconnected nanoparticles with narrow pore size distribution. Such pDCPD-X-MMA aerogels demonstrate excellent mechanical strength.

Organofluorine Compounds: From Superacids to Medicinal Chemistry

V. Prakash Reddy, Dept. of Chem., MS&T

Abstract: Due to the unique properties of C-F bond, organofluorine compounds have unusual physicochemical properties.  They are components of superacids, widely used polymeric materials, anesthetics, agrochemicals, as well as numerous pharmaceuticals.  Understanding the effects of C-F bond on the stabilization of reactive intermediates is essential in designing new synthetic methods, and for the designing of the biologically and medicinally active compounds.  In general, fluoroalkyl groups such as trifluoromethyl and gem-difluoromethylene groups are expected to destabilize the carbocationic intermediates. However, experimental evidence is of limited scope for the fluorinated carbocation intermediates due to the difficulty of their formation.  Insights gained from the effect of substituents on the relative stabilization or destabilization of the carbocations and other reactive intermediates, in conjunction with factors such as hydrophobic and lipophilic nature of fluorinated compounds are of fundamental interest in the design of the biologically and medicinally relevant novel organofluorine compounds.  In this context, our studies on some of the fluorinated carbocations in superacid media and overview of our recent synthetic strategies for organofluorine compounds will be discussed.

The Characterization of Ultrafine Particulate Matter from Combustion Processes

Philip D. Whitefield, Dept. of Chem., MS&T

Abstract: This presentation will discuss the need for ultrafine particulate matter (PM) characterization for both environmental, economic and defense related purposes.  It will provide a basic introduction to the fast, real time experimental methods employed to determine PM, size distribution, number and mass concentration, composition and hydration properties using extractive sampling methods.  The application of these methods will be described using examples from the work of the Aerospace Emissions Program at MS&T.   In particular gas turbine engine emission characteristics using conventional and alternative aviation fuels will be described as will the changes observed in the PM properties as the engine exhaust expands and disperses in the engine exhaust plume.

Correlation for Yield of Competitive Reactions in Reactors with Turbulent Mixing

Gary K. Patterson, Dept. of Chemical and Biological Engineering, MS&T

Abstract: A correlation for yield of a product of competitive reactions with turbulent mixing resulted in a plot of [yield/perfect yield] versus a mixing Damkoehler number, the ratio of mixing time to reaction time, written as follows:  DaM = τMR, where τM ≈ 2(L2/ε)1/3 and τR = 1/(k1k2CAfCBres)1/2.  Such competitive reactions are represented by A + B  R; R + B  S and A + B → R; C + B   S.  The scale of mixing L is approximated in a stirred vessel by Df = (4Qf/πUbt)1/2  and the rate of turbulence energy dissipation rate in a stirred vessel ε is given by NiNPD2N3/[(T/D)3(π/4)].  [Symbols are defined as follows:  k1 and k2 are rate constants for reactions 1 and 2, CAf and CBres are molar concentrations of the feed A and the resident B, Df is the diameter of the feed jet as stretched or compressed by the flow, Qf is the volumetric feed rate, Ubt is the blade tip speed of an impeller, Ni is the ratio εfeed pointaverage , NP is the impeller power number, N is the impeller rotation rate, T is the vessel diameter, and D is the impeller diameter.]

     A recent more detailed dimensional analysis has shown the need to include the effect of the ratio of reaction rate constants, k2/k1, in the correlation, even though the ratio of yield to perfect yield removes most of the divergence.  The new correlation effectively separates experimental data for different k2/k1-ratios.  The seminar will include the details of the dimensional analysis, consequences for other types of mixed reactors, for instance static mixers, and sources of data used.

 

 

Learning in the Undergraduate Chemistry Laboratory: Perspective from a South African Research University

Karen Wallace, University of Western Cape, South Africa

Abstract: First-year chemistry students at most South African universities typically had limited or no exposure to laboratory work while at school. This applies especially to students from lower socio-economic beginnings who attended township or rural schools. The University of the Western Cape (UWC), a historically black university (HBU), draws at least half of its students from this demographic.

My presentation will focus on two aspects of laboratory learning that is addressed by my research in the above context, namely:

  • The role of the postgraduate students as facilitators in the first-year laboratory experience; and
  • The use of online video clips to support student preparation for laboratories. 

Addressing the first of these, I will report on a qualitative study performed in my department to characterise postgraduate participation in the undergraduate laboratories. Teaching assistants (or demonstrators as they are called at South African universities) have become indispensable to the delivery of teaching particularly to first-year students, due mainly to the growing need in tertiary institutions to balance increasing student numbers and needs with pressure on academic staff time and institutional resources. At most universities the role of teaching assistants falls to postgraduate students who are being trained in disciplinary research. In addition to funding their own studies, their participation in teaching activities is increasingly being recognised as preparation for possible careers in tertiary teaching.

A theoretical framework that views learning as participation in a community of practice was used to characterise demonstrators’ engagement with their task of facilitating student learning. Learning as participation is more than engagement in the activities and practices of a social or professional group of people; it encompasses both active participation and the construction of an identity in relation to the group and its practices. I will attempt to present a qualitative interpretation of what learning in a demonstrator/postgraduate community might mean: from emerging conceptions about student learning and the learning of chemistry, to a deeper understanding of the meanings of professional behaviour and academic enterprise. I will also report on the outcomes of an intercessionary process consisting of various measures aimed at improving demonstrating practice in the first-year laboratories at my institution.

The second aspect of laboratory learning that will be addressed is student preparation for laboratory work. Students attending the first-year chemistry laboratory course at UWC are required to prepare a flow diagram, showing the procedure they intend to follow during the execution of the practical, prior to each laboratory session. The rationale behind this requirement is to increase the students’ level of preparation for laboratories, with at least some of the transformative tasks occupying the working memory during the execution of the practical taken care of beforehand. In order to assist students in the transformation of procedural texts into flow diagrams, short video clips were uploaded to UWCs e-learning platform. The results of a pilot experiment in which the flow diagrams of students who had watched the clips were compared with those of students who had not watched the clips will be presented.

Chemistry of the Solar System

Dennis L. Whitney, Environmental Engineer, American Airlines, Retired

Abstract: The nature of the creation of the environment we inhabit has intrigued philosophers since the dawn of our conciseness.

The application of the principles of nuclear, inorganic, and geological chemistry to the study of geological specimens and meteorites has led to new insight into the nature of the process that have lead to our current environment. The fact that the earth supports life seems to have an important effect on the nature of this environment.

Probing Actinide Electronic Structure Using High-resolution Photoelectron Spectroscopy

Dr. Michael C. Heaven, Dept. of Chem., Emory University

Abstract: High-level theoretical models of the electronic structures and properties of actinide compounds are being developed by several research groups.  This is a challenging problem due to the need for explicit treatment of relativistic effects, and the circumstance that many of these molecules exist in states where the f and/or dorbitals are partially filled.  Current theoretical models are being evaluated through comparisons with experimental results.  Gas phase data are most suitable for this purpose, but there have been very few gas phase studies of actinide compounds.  We are addressing this issue by carrying out spectroscopic studies of simple uranium and thorium compounds.  Multiple resonance spectroscopy and jet cooling techniques are being used to unravel the complex electronic spectra of these compounds. 

          Our recent studies have focused on the electronic structures of the oxides, sulfides fluorides and nitrides of Th and Hf.  Comparisons between isoelectronic species indicate that relativistic affects play a relatively minor role in the ionic bonding of ThO, ThO+, ThF and ThF+.  ThO and the ions HfF+ and ThF+ have been identified as excellent candidates for measurements that probe the electric dipole moment of the electron (a manifestation of CP symmetry violation).  The characteristics that render these molecules favorable for studies of fundamental constants will be reviewed, and the first gas phase spectra for the Th fluoride and nitride species will be presented.

NMR Experiments Performed in Weak and Inhomogeneous Magnetic Fields

Dr. Rex E. Geral, Dept. of Chem., MS&T

 

Photorefractive Polyvinyl Carbazol Composites Using PbS Nanocrystals as a Photosensitizer

Jong-Sik Moon, Dept. of Chem., MS&T

Abstract: Inspired by the promise of enhanced spectral response, photorefractive polymeric composites photosensitized with semiconductor nanocrystals have emerged as an important class of materials. In addition to providing efficient photosensitization, however, extensive study of these hybrid composites has indicated that the inclusion of nanocrystals also provides an enhancement in the charge-carrier mobility, and subsequent reduction in the photorefractive response time. Unfortunately, the included nanocrystals have also been shown in most cases to increase the deep trap concentration, resulting in a significant decrease in the photorefractive performance, specifically diminished diffraction efficiencies as well as reduced two beam coupling gain coefficients. Nonetheless, evidence suggests that this problem can be largely avoided through the inclusion of semiconductor nanocrystals possessing a relatively narrow band-gap. Here, we fully exploit this quality by doping PbS nanocrystals into a newly formulated photorefractive composite based on molecular triphenyldiamine photosensitized with C60. Through this approach, unprecedented response times of 400 ms are observed, opening the door for video and other high-speed applications. It is further demonstrated that this improvement in response time occurs with little sacrifice in photorefractive efficiency, with internal diffraction efficiencies of 72% and two-beam-coupling gain coefficients of 500 cm-1 being measured. A thorough analysis of the experimental data is presented, supporting the hypothesized mechanism of enhanced charge mobility without the accompaniment of superfluous traps. It is anticipated that this approach can play a significant role in the eventual commercialization of this class of materials.

 

 

 

The Chemistry and Remarkable Applications of Cyanoximes and their Metal Complexes

Nikolay Gerasimchuk, Dept. of Chem., Missouri State University

Abstract: During the last two decades my research interests were dedicated to the new class of weak organic acids – cyanoximes. These low molecular weight organic molecules represent series of new ligands for coordination chemistry.[1] Both unbound to metal free ligands, their Na+ and K+ salts and other metal complexes show a large spectrum of biological activity from growth regulation in plants to in vitro cytotoxicity. Currently 37 cyanoximes are known, and were more than two hundreds cyanoxime complexes synthesized and studied using a variety of different spectroscopic methods and x-ray analysis. Stereochemistry of cyanoxime ligands,[2] structures and properties of the most interesting coordinations compounds are reviewed in this presentation.[3,4] A broad spectrum of applications of both cyanoximes and their metal complexes is outlined in this lecture as well.[5-11]  

How to Use Gaussian09 at MS&T? What Can You Learn from Gaussian09?

Richard Dawes, Dept. of Chem., MS&T

 

2012

General Laboratory Safety Training

Phyllis Lewis, Environmental Specialist, Environmental Health & Safety

Abstract: 

  • Hazardous Waste Management
    • Federal Regulation & University Policy
    • Types of waste handled by Environmental Health and Safety
      • Chemical, Bio-hazardous, Universal
    • Proper storage of wastes
    • Proper labeling of wastes
    • Filling out the waste pick-up request form
    • Fire Safety (10 minute video)
    • Spill Response
  • Laboratory Safety
    • General laboratory housekeeping
    • Safety policies
    • Common hazards in the laboratory
      • Chemicals, Bio-hazards, Radiation, Compressed Gas Cylinders
    • Labeling & Storage
    • Chemical inventory:  Chemtrack
    • Personal Protective Equipment
    • Emergency Response

The Characterization of Ultrafine Particulate Matter from Combustion Processes (Continued)

Philip D. Whitefield, Dept. of Chem., MS&T

 Abstract: This presentation will discuss the need for ultrafine particulate matter (PM) characterization for both environmental, economic and defense related purposes.  It will provide a basic introduction to the fast, real time experimental methods employed to determine PM, size distribution, number and mass concentration, composition and hydration properties using extractive sampling methods.  The application of these methods will be described using examples from the work of the Aerospace Emissions Program at MS&T.   In particular gas turbine engine emission characteristics using conventional and alternative aviation fuels will be described as will the changes observed in the PM properties as the engine exhaust expands and disperses in the engine exhaust plume.

The Use of SciFinder in Chemical Research

Dr. Steve Dueball, Applications Specialist, Chemical Abstract Service, American Chemical Society

Chelating Compounds as Potential Flash Rust Inhibitors in Waterborne Coating Systems

Jigar Mistry, MS&T

Abstract: 

Part 1: Chelating Compounds as Potential Flash Rust Inhibitors in Waterborne Coating Systems

 Waterborne coatings on ferrous substrates usually show flash rusting which decreases the adhesion of the coating and the corrosion products can form a stain. This study investigates chelating compounds as potential flash rust inhibitors.  Compounds being evaluated include amine alcohols, diamines and sulfur containing amines.  A new corrosion inhibitor 2,5-(S-acetic acid)-dimercapto-1,3,4-thiadiazole (H2ADTZ) was synthesized. The performance characteristics of this new-generation additive as a flash rust inhibitor were evaluated. 

Part 2: 1,3,2-Thiadiazolidine-2,5-dithione: Synthesis and Structure of Alkylated Derivatives

The observed structure of 1,3,2-thiadiazolidine-2,5-dithion (also known as 2,5-dimercapto-1,3,4-thiadiazole (DMTD)) has been previous reported in three different forms including  -Dithiol and -Dithion tautomeric isomers. This paper clarifies which structure is the correct one and also reports synthesis and characterization of the structure of mono- and dialkylated DMTD. The methods of x-ray crystallography, NMR spectroscopy and ab-initio electronic sturcture calculations were combined to aid in understanding the reactivity and structure of each compound. 

Part 3: Melamine & Aziridine Cure of Acrylic Colloidal Unimolecular Polymers. 

Colloidal unimolecular polymers (CUPs) were prepared and tested for application as a coating resin.  These CUP particles were true nano particles and were found to be crosslinkable with melamine and aziridine.  Formulations were prepared with melamine for bake cure and with aziridine for both bake and ambient cure coatings.  These formulations were evaluated for MEK abrasion resistance, adhesion, hardness, gloss, flexibility, abrasion and impact resistance properties. The formulated new clear coat resin system has a low VOC and good gloss and transparency.

 

Electrodeposition/Eletrochemical Reduction of Epitaxial Metal Oxide Films and Superlattices

Zhen He, Dept. of Chem., MS&T

Abstract: 

Part 1: Electrodeposition of CoxFe3-xO4 Epitaxial Films and Superlattices. Spinel ferrites are of interest because of their potential applications in spintronics (spin-based electronics), nonvolatile memories, and magnetoreception devices. Cobalt ferrite (CoFe2O4) is an inverse spinel ferrite. The utility of CoFe2O4 is mainly based on its high coercivity, and magnetocrystalline and shape anisotropy. The magnetic and electric properties of CoFe2O4 depend on its Co:Fe ratio. Here, we present a one-step electrodeposition of CoxFe3-xO4 (0<x<1) thin films from an alkaline Fe3+-Co2+-triethanolamine solution. The atomic Co:Fe ratio in the deposited CoxFe3-xO4 thin films can be tuned by controlling the deposition potential. The effects of the chemical composition on the structure and electric properties of the CoxFe3-xO4 films are investigated. Superlattices in CoxFe3-xO4 system are also electrodeposited from the same solution by simply pulsing between two potentials. Compared to CoxFe3-xOindividual films, superlattices exhibit resistance switching and a more pronounced negative differential resistance (NDR) feature at lower current during perpendicular transport measurements.

Part 2: Room-Temperature Electorchemical Reduction of Epitaxial Magnetite Films to Epitaxial Iron Films.

The electorchemical reduction of oxides to metals has been studied for decades. Eralier work produced polycrystalline bulk metals. Here, we report that pre-electrodeposited epitaxial face-centered cubic magnetite thin films can be electrochemically reduced to epitaxial body centered cubic iron thin films in an aqueous solution on single crystalline gold substrates at roome temperature. This technique opens new possibilites to produce special epitaxial metal/metal oxide heterojunctions and a wide range of epitaxial metallic alloy films from the corresponding mixed metal oxides. 

Developing Novel Synthesis Protocols for the Fabrication of Functional Nanomaterials for Advanced Devices

Sukhada Patil, Dept. of Chem., MS&T

Abstract: 

Patterned Growth of CdTe Nanowire Arrays for High Efficiency Solar Cells.

In modern nanodevices while nanostructuring is expected to increase the efficiency of the device manifold, the device geometry also plays an important role in determining the practicability of the device. In that regards, the real challenge lies in assembling the semiconducting nanowires in pre-determined regions to increase the signal to noise ratio to a practically useable value. We have successfully developed a simple, reproducible and scalable technique for growing nanowires as dense arrays on patterned substrates through electrodeposition on patterned nanoelectrodes. The success of protocol was tested on CdTe as model system, as CdTe is potential economical substitute for Si. It is easily synthesizable, and has a forgiving composition where the photovoltaic efficiency is retained over a considerable stoichiometry range. The vertically aligned CdTe nanowires grown over large area by our technique were exceptionally homogeneous in terms of the nanowires diameter and length. The ensemble of the CdTe nanowire arrays covering an area of 65 X 65 μm2, exhibited a photocurrent density in the mA range, which was higher than that of CdTe film grown under similar conditions. Results for patterned nanowires growth encompassing CdTe and other nanowires growth would be discussed in detail.

Synthesis of Superconducting Nanocables of Iron Selenide Encapsulated in Carbon Nanotubes.

Another technically important material for nanodevices is superconductors. Recent discovery of superconductivity in iron selenide have attracted considerable attention due to the simplicity of the structure. We have synthesized superconducting FeSe nanowires encapsulated inside carbon nanotubes by a simple vapor transport reaction at 800°C. The superconductivity of these nanocables was determined through magnetic measurement and Tc of 10K was obtained for the ensemble of nanowires. The FeSe filling length inside the carbon nanotubes could be varied through controlling reaction conditions and the diameter of nanowires could be controlled through reaction parameters. Carbon nanotubes protect the FeSe nanowires from O2/moisture and also under e-beam damage while preserving superconducting characteristics.

 

Designing Novel Synthesis for Production of Functional Nanowires and Nanoarrays of Superconducting and Thermoelectric Materials

Prachi Sood, Dept. of Chem., MS&T

Abstract: 

Part A: Quest for obtaining superconducting nanowires from Fe pnictide based superconductors.

Recently iron pnictide based compounds have been under immense scrutiny owing to discovery of superconductivity in the doped LnFeAsO (1111) and the AFeAs (A = alkali metal) series.  The iron pnictide layer is believed to be responsible for superconductivity in these compounds.  Nanostructures of these superconductors are perfect low dimensional models for understanding the fundamental properties of these novel superconductors.  The sacrificial template method can be possibly used to synthesize nanostructured morphologies of these superconductors, where, one of the reactants, the binary iron pnictide will be used as a morphology directing agent. We have developed a one-pot soft chemical method to synthesize monodisperse iron arsenide core- shell nanoparticles. These FeAs nanoparticles are phase pure and superparamagnetic as revealed by powder x-ray diffraction and magnetic characterization. The highest TB achieved is 247 K.  Further, attempts are being made to introduce alkali metal ions in the solution to form nanostructures of the ternary [111] superconducting phase.  Results encompassing synthesis of FeAs nanoparticles and LiFeAs nanowires and [111] nanostructures will be presented.

 Part B: Producing nanowires arrays of high ZT thermoelectric materials.

Chalcogenides have been proven to have excellent thermoelectric properties. According to recent reports it has been proven that the nanostructures especially the nanowires increase ZT of thermoelectric materials by increasing the phonon boundary scattering. Recently, Na doped PbS- PbTe alloy thermoelectric systems have attracted attention due to their high power factor. Modification of density of states (DOS) by substitution of Te by Se effectively tunes the location of the valence bands of PbTe, which at high doping can maximize promotion of carriers into the heavy hole band to enhance power factor. It can be argued that nano columns of such a system containing basal p - type PbTe layer with cubic PbS with 2% Na doping can further increase the magnitude of ZT.  Such functional arrays can be used as practical devices integrated within the device geometry. Preliminary results in this project will be shared.

 

 

 

Oxidative Stress and Cardiovascular Diseases

Arunendra Saha Ray, Dept. of Chem., MS&T

 

Molecular and Electronic Structure of Transition Metal and Actinide Complexes with Monoanionic Schiff Base Ligands

Dr. Justin Walensky, Dept. of Chem., University of Missouri-Columbia

 

Biorenewable Composites from Vegetable Oil

Rongpeng Wang, Dept. of Chem., MS&T

 

Characterization of Polymer Patterns Used in the Metal Castings Process

Hongfang Zhao, Dept. of Chem., MS&T

Abstract: Investment casting, known as a lost-wax casting, has been widely employed to manufacture of quality metal components in automobile, aerospace and biomedical industries because of its ability to produce accurate and complex castings. In a investment casting process, a wax pattern is dipped in ceramic slurry to form the ceramic shell and then is removed by melted or burned out in an autoclave to create cavities; molten metal is introduced in the mold and solidified to form the casting. Finally the ceramic shell is destroyed to release the metal castings. While there are some limitations of wax pattern, such as distortion when storing and handling issues due to weight and brittleness. In addition, as the demand of industry, wax pattern could be replaced by polymer pattern because of its advantages of less expansion on heating, facilitated pattern removal, in some cases less expensive and handling easily. Applicability of different low density rigid polymer pattern materials for investment casting process was experimentally investigated. Densities, elastic moduli and thermal expansion of polymer patterns were measured. Pattern removal process from the shell was examined by thermal gravimetrical analysis (TGA). Comparison was done among physico-chemical properties of different low density rigid polymer pattern materials important for the investment casting process. The simulation of another metal casting process, lost foam casting, was performed by suing Magmasoft to help to predict and improve the casting qualities.

 

General Laboratory Safety Training

Phyllis Lewis, Environmental Specialist, Environmental Health and Safety

Abstract: 

  • Hazardous Waste Management
    • Federal Regulation & University Policy
    • Types of waste handled by Environmental Health and Safety
      • Chemical, Bio-hazardous, Universal
    • Proper storage of wastes
    • Proper labeling of wastes
    • Filling out the waste pick-up request form
    • Fire Safety (10 minute video)
    • Spill Response
  • Laboratory Safety
    • General laboratory housekeeping
    • Safety policies
    • Common hazards in the laboratory
      • Chemicals, Bio-hazards, Radiation, Compressed Gas Cylinders
    • Labeling & Storage
    • Chemical inventory:  Chemtrack
    • Personal Protective Equipment
    • Emergency Response

Occurrence, Degradation, and Control/Limitation of Emerging Dirnking Water Contaminants in Missouri Drinking Water Systems

Dr. Honglan Shi, Dept. of Chem., MS&T

Abstract: Emerging contaminants in drinking water is a very active research area in recent years due to their common concurrent and uncertain risks to human health. Many drinking water emerging contaminants, including pharmaceuticals and personal care products (PPCP), N-nitrosamines (including NDMA), perchlorate, chlorination disinfection byproducts (including halonitromethanes, and iodo-DBPs), cyano(algal)toxins, and pesticide degradation products in Missouri drinking water and source water systems, have been studied. These studies include occurrence screening, formation and degradation, and removal. Due to the very low concentrations of these contaminants in drinking water, several ultra-sensitive and rapid analytical methods have been developed by using state-of-the-art instrumentation such as ultra-fast liquid chromatography tandem mass spectrometry and gas chromatography-mass spectrometry. Major different source waters (river water, lake water, and underground well water) have been included in these studies.  Different methods for control and removal of these water contaminants have been developed/evaluated with both adsorption and oxidation technologies. Different oxidative treatments and conditions, activated carbon and nano-materials for removal efficiency of the contaminants and their precursors will also be overviewed.

Rapid Screening Methods for On-Site Pharmaceutical Surveillance

Connie M. Gryniewicz-Ruzicka, CDER, Division of Pharmaceutical Analysis, U.S. Food and Drug Administration, Saint Louis, MO

Abstract: Consumer exposure to poor quality, counterfeit and adulterated pharmaceutical products has prompted the FDA to develop rapid and reliable screening methods to assess the quality and safety of pharmaceutical products.  Spectroscopic methods are attractive for this application because portable formats are available and samples can Consumer exposure to poor quality, counterfeit and adulterated pharmaceutical products has prompted the FDA to develop rapid and reliable screening methods to assess the quality and safety of pharmaceutical products.  Spectroscopic methods are attractive for this application because portable formats are available and samples can be analyzed on-site with analysis times on the order of minutes.  This presentation will briefly describe the current spectroscopic methods, including Raman, near infrared (NIR), x-ray fluorescence (XRF) and ion mobility (IMS) spectrometries, being utilized by the FDA for field surveillance of pharmaceutical products. Method development, chemometric data analysis and field deployment will be discussed. 

 

 

Opportunities in Nanoscience with Gold Nanoparticles

Dr. George C. Schatz, Dept. of Chem., Northwestern University

 

 

 

Creating Functional Nanostructures for Smart Devices

Dr. Manashi Nath, Dept. of Chem., MS&T

 

 

 

In Vivo Microdialysis Studies of Seizure Induced Oxidative Stress

Dr. Craig E. Lunte, Dept. of Chem., University of Kansas

Abstract: It has been postulated that oxidative stress is a result of several neurobiological conditions, including epilepsy.  Epilepsy is a disease that affects 1% of the worlds population1. Of that 1%, it is estimated that 20% are resistant to current medications2.  An important secondary effect of seizures is oxidative stress.  Oxidative stress is a result of a deviation from the body’s natural balance between reactive oxygen species (ROS) and endogenous antioxidants, which act to deplete ROS in the body.  Oxidative stress due to epileptic seizures can cause localized neurotoxicity, which can in turn affect a multitude of biochemical pathways.  Specifically, localized brain damage from seizures leads to imbalances in ion and neurotransmitter levels, changing membrane potentials, which results in neuronal hyperexcitability.  The increase of glutamate and catecholamines and subsequent Ca2+ influx specifically lead to ROS formation.  It has been reported that ROS levels increase during and after seizure events3,4.  In addition to epilepsy, oxidative stress in the brain plays an important role in cellular damage due to methamphetamine use5, chronic diseases (i.e. bipolar disorder6) and in degenerative diseases (i.e. scrapie7 and Alzheimer’s disease8,9).

      The goal of this study was to use both a status epilepticus steady-state chemical model and a focal seizure model in rats using the convulsant, 3-mercaptopropionic acid (3-MPA), and to compare the changes in striatal neurotransmission to several biomarkers of oxidative stress.  In vivo microdialysis was combined with electrophysiological methods in order to provide a complete evaluation of the dynamics of the results obtained. The biomarkers monitored included, malondialdehyle (MDA) as a marker of lipid peroxidation, nitrite as a marker of reactive nitrogen species formation, and several prostaglandins.  The neurotransmitters monitored were GABA, glutamate, and the catecholamines.

            In the status epilepticus (systemic dosing) model, glutamate increased and GABA decreased monotonically while changes in dopamine (DA) concentration were bimodal.  Electrical activity in the brain rapidly returned to normal after administration of 3-MPA ceased, while glutamate remained elevated and GABA depressed for several hours after administration ceased. Administration of cyclothiazide (CTZ) diminished neurotransmitter activity but not the changes in GABA and glutamate, possibly indicating Glu receptor desensitization with the seizure model.

      Interestingly, in the focal ischemia model, both glutamate and GABA were observed to increase.  The increase in glutamate was several times greater than that of GABA, indicating that excitatory processes still dominated.  The ECoG data for the focal seizure (local dosing) model were inconsistent and weak when observed.  This was a result of the very local nature of the excitatory event and difficulty in co-locating the microdialysis probe and recording electrode.

      In this model, MDA was observed to increase upon administration of 3-MPA, indicating that lipid peroxidation was occurring.  No changes in nitrite were observed indicating that this was not a result of reactive nitrogen species being formed.  A small increase in several prostaglandins has been observed, but the changes are small.  We are working to improve our analytical method for determination of prostaglandins and hope to have more significant results in the near future.

 

 

 

Nanopore in Personalized Medicine: Single-Molecule Epigenetic Study

Dr. Li-Qun Gu, Dalton Cardiovascular Research Center, Dept. of Biological Engineering, University of Missouri-Columbia

Abstract: Nanopores are nanometer-wide tiny pores fabricated using modern protein engineering and fashion nanotechnology. Due to the molecular-scale pore size, the binding of a single analyte molecule to the pore lumen can characteristically alter the ion current through the pore. The current change is specific to the type of target molecules and their configuration in the pore, therefore generating a signature that serves as an electronic fingerprint for target molecule recognition. Used as a biosensor, the nanopore can simultaneously identify and quantify multiple target species for a variety of biomedical detections, with targets ranging from metal ions and cellular second messengers to protein and pathogen oligonucleotides. The nanopore is being developed as a rapid, label-free and low-cost technology for DNA sequencing and various genetic and epigenetic detections. Toward this goal, single-molecule nucleic acids and their interaction with nanopore has been extensively characterized, which includes many topics such as how the nanopore conductance is sensitively changed with the sequence of a single-stranded DNA or RNA in pore and how a double-stranded DNA is unfolded. We developed a new generation of programmable nanopore biosensors, called aptamer-integrated nanopore. Such a single molecule detector is integrated with aptamers, in vitro created short nucleic acids molecules that mimic antibodies to bind target proteins with high selectivity and high sensitivity. The nanopore sensor is being combined with smart polymers and microfludics to create robust chip device for future medical diagnosis, treatment, and high-throughput screening at the molecular level. Recently, we proposed a robust nanopore method of differentiating and quantifying cancer-associated microRNAs (miRNAs) in human blood samples, an approach with the potential in non-invasive and cost-effective cancer detection. MiRNAs are small regulating RNA molecules that are recognized as potential biomarkers of cancers.

Investigation of Native Microalgae as Sustainable Sources of Fuel, Feed, and Food

Dayananda Chandrappa, Dept. of Chem., MS&T

Microchip-based Analysis Systems for Monitoring Biological Events

Dr. R. Scott Martin, Dept. of Chem., Saint Louis University

Abstract: The use of microchip-based devices for performing analytical assays such as separations has become an established research area.  While one of the often stated advantages of these systems is integration of multiple processes, there are very few studies that involve the use of microchips to integrate cell-based in vitro mimics with an analysis system.  This talk will discuss work from our labs on developing such a system.  This approach uses a microfluidic device that integrates multiple processes such as cell culture, fluidic pumping, valving, electrophoresis and electrochemical detection.  Issues encountered with integrating these otherwise separate techniques will be discussed as will the use of the device to continuously monitor the on-chip stimulated release of neurotransmitters from PC 12 cells.  In addition, recent work towards developing polystyrene-based microchip devices to improve the success of on-chip cell culture as well as the performance of electrochemical detection will be presented.

Chemical Doping of Topological Insulators

Yew San Hor, Dept. of Physics, MS&T

Abstract: A novel kind of three-dimensional insulators called topological insulators, which have a bulk insulating gap but non-trivial topological surface states has been discovered. The surface states of these topological insulators show Dirac-like behavior with the spin polarization locked perpendicular to the electron momentum by the effect of strong spin-orbit interaction. As the locking protects the surface electrons from back scattering, they are predicted to have high mobilities. The spin-resolved nature of the surface states has been confirmed in angle-resolved photoemission spectroscopy experiments. However, it has been a challenge to resolve the lack of transport information due to the dominant bulk conductance in the material. By chemical doping, the chemical potential of the material can be tuned to fall inside the band gap and therefore suppress the bulk conductivity. On the other hand, a topological insulator can also be tuned to a bulk superconductor. This means that Cooper pairing is possible in a topological insulator with implications for study of Majorana fermion physics and potential quantum computing devices. Moreover, detection of the surface currents is a crucial first step in the investigation of novel phenomena, such as axion electrodynamics, in magnetic doped topological insulators.

Advanced Microcontrollers in the Chemistry Laboratory: Stirred and Temperature-Regulated Reaction

Dr. Rex E. Gerald, Dept. of Chem., MS&T

Role of NACA in Radiation Induced Oxidative Stress in Cancer Therapy

Rakesh Kacham, Dept. of Chem., MS&T

Comparative Evaluation between N-Acetyl Cysteine and N-Acetyl Cysteine Amide in Acetaminophen-Induced Oxidative Stress

Ahdab N. Khayyat, Dept. of Chem., MS&T

Abstract: Acetaminophen (APAP) is the most widely used pharmaceutical analgesic-antipyretic agent in the world, but its toxicity is a common cause of drug-induced hepatotoxicity. With APAP toxicity, cellular glutathione (GSH) is depleted. This results in the availability of N-acetyl-p-benzoquinone imine (NAPQI) that binds to cellular macromolecules, which leads to cell necrosis. N-acetyl cysteine (NAC), a GSH precursor, is the only approved antidote for an acetaminophen overdose. It is a negatively charged molecule that diminishes its penetration into the cells, thereby requiring fairly high doses that increase the side effects. In addition, oral and I.V. administration of NAC in a hospital setting is laborious and costly. Recently, a neutral compound that is structurally very similar to NAC (an amide form of NAC, called NACA) has been developed to improve NAC’s bio-availability.Therefore, in this study, we conducted an investigation to determine the mechanism of APAP- induced hepatotoxicity. We also evaluated the hepatoprotective effectiveness of NACA and compared it with NAC in the hepatic cell line, HepaRG. This comparison was based on several oxidative stress parameters, including the levels of intracellular reactive oxygen species, GSH, various antioxidant enzyme activities, mitochondrial membrane potential, and lactate dehydrogenase levels. Our preliminary data shows a dose-dependent decrease in cell viability in HepaRG cells upon exposure to APAP for 24 hours. The cell viability decreased to approximately 50% of the control when treated with 20mM APAP which increased to 70% upon NACA pretreatment. Oxidative stress parameters, upon NACA and NAC pretreatment are compared and discussed.

 

2013

General Laboratory Safety Training

Phyllis Lewis, Environmental Specialist, Environmental Health and Safety

Abstract:

Hazardous Waste Management

  • Federal Regulation & University Policy
  • Types of waste handled by Environmental Health and Safety
    • Chemical, Bio-hazardous, Universal
  • Proper storage of wastes
  • Proper labeling of wastes
  • Filling out the waste pick-up request form
  • Fire Safety (10 minute video)
  • Spill Response 

Laboratory Safety

  • General laboratory housekeeping
  • Safety policies
  • Common hazards in the laboratory
    • Chemicals, Bio-hazards, Radiation, Compressed Gas Cylinders
  • Labeling & Storage
  • Chemical inventory:  Chemtrack
  • Personal Protective Equipment
  • Emergency Response

Using Agricultural By-products as Sorbents to Treat Metal Pollution

Dan Yongbo, Dept. of Chem., MS&T

 

Dynamics of Cycloaddition Reactions

Dr. Lai Xu, Dept. of Chem., MS&T

 

Mechanically Strong Nanoporous 3D Assemblies of Metal, Polymer, and Carbon Aerogels

Shruti Suryakant Mahadik, Dept. of Chem, MS&T

 

Nanostructure-initiator Mass Spectrometry with Acoustic Depostition: Multiplexed, High-throughput Pipeline for Metabolic and Enzymatic Activity Screening

Xiaoliang Cheng, Life Science Division, Lawrence Berkeley National Laboratory

Abstract: A major challenge in Synthetic Genomics is the disconnect between the rate of gene discovery and functional analysis. Determining the function of a gene now requires a disproportionate amount of effort relative to that required for gene identification. Similarly, construction of multigene pathways for biofuel production is relatively straightforward and results in enormous clone libraries, however, only a small fraction of clones can be tested due to analysis constraints inherent with traditional LC/GC-MS analysis. We are addressing this analytical bottleneck using acoustic printing to transfer nanoliter volumes onto nanostructure-initiator mass spectrometry surfaces, enabling us to perform 10,000’s of assays/day, an increase in throughput of 1000-fold. This effort will serve as the foundation in the development of this new technology that will have several applications, including enzyme "cocktail" engineering for enhanced performance in industrially relevant biorefining operating environments for the production of sugars from biomass.

 

Isocyanate Derived Organic Aerogels

Chakkaravarthy Chidambareswarapattar, Dept. of Chem., MS&T

Abstract: Aerogels are bulk monolithic materials, consisting of 3D assemblies of nanoparticles with high open porosity, high surface areas and are pursued for thermal insulation.  After the synthesis of resorcinol-formaldehyde (RF) aerogels in 1989, for a number of years “organic aerogels” and “RF-aerogels” were almost synonymous terms.  This is slowly changing as other classes of organic aerogels show up in the literature, including polyurethane, polyurea and more recently polystyrene, polybenzoxazine, polydicylcopentadiene and polyimide (PI) aerogels. The latter are pursued for the good chemical resistance, excellent mechanical properties and high thermal stability of their polyimide skeletal framework.  Typically, polyimides are synthesized from a di-anhydride and a diamine with the classic DuPont two-step process via polyamic acids, which are converted to polyimides chemically with the use of dehydrating agents (e.g., acetic anhydride) along with base catalysts (e.g., pyridine).  The first PI aerogels were described in 2006, and they were synthesized by that route.  Here, we report polyimide aerogels via an alternative one-step room-temperature route that involves reaction of the same dianhydrides with the corresponding diisocyanates. The final aerogels are chemically indistinguishable (by IR and 13C CPMAS NMR) from those synthesized via the polyamic acid route. However, in terms of properties, the two materials are vastly different. Aerogels synthesized via the isocyanate route are nanofibrous as opposed to nanoparticulate morphology obtained from the amine route.

Following our successful synthesis of PI aerogels via the one-step isocyanate route [1], we have correlated bulk mechanical properties with the structure of the monomers.  Thus, realizing the importance of multifunctional monomers in terms of imparting mechanical strength, we resort into a trifunctional isocyanate [tris(4-isocyanatophenylmethane): Desmodur RE; courtesy of Bayer, Corp. USA] with two different di-anhydrides, pyromellitic dianhydride (PMDA) and benzophenone tetracarboxylic dianhydride (BTDA).  The resulting polyimide aerogels, PI-PMDA and PI-BTDA, are stable up to 400 oC (by TGA), as expected from polyimides. Despite relatively high bulk densities by aerogel standards (up to 0.6-0.7 g cm-3) and a decrease in porosity (down to ~50% v/v) PI-PMDA remain mesoporous and have high surface area (up to 435 m2 g-1). On the other hand, with the same primary particle sizes, PI-BTDA shrink less, have lower bulk densities and higher porosities (up to 80%). Clearly, decreasing the molecular rigidity of the dianhydride (from PMDA to BTDA) has an immediate impact on the material properties of the resulting aerogels. Both kinds of PI aerogels are extremely robust materials with high energy absorption capabilities (e.g., PI-PMDA: 82±4 J g-1 at 0.68 g cm-3; PI-BTDA: 47±1 J g-1 at 0.37 g cm-3).  Upon pyrolysis at 800 oC under Ar, PI aerogels are converted to carbon aerogels in high yields (52-59 % w/w).   Along the way, design of other isocyanate derived organic aerogels is briefly discussed.

 

 

Grabbing Scorpions: Fast, Functional Resin-Supported Chelates

Prof. Patrick Desrochers, Dept. of Chem., University of Central Arkansas

Abstract: The rapid one-pot synthesis of a functional scorpionate using microwave assisted methods will be described.  Despite the 50+ year history and vitality of the scorpionate field (typically hydrotris(pyrazolyl)borate chelates used with every metal on the periodic table), the development of heterogeneous supported scorpionates is still in its infancy, with our own work (Inorg. Chem. 2011) representing one of only a handful of examples.  The promise is great: couple the benefits of mature ligand development with the proven utility of heterogeneous systems.  Immobilized metal affinity chromatography and high-throughput combinatorial methods are two such areas that could benefit from the use of versatile metal scorpionate chelates. The challenge is also great: supported scorpionates are generally difficult or expensive to make.  Therefore, we demonstrate that such chelates can be reproducibly prepared inexpensively in a single step by MW irradiation of a mixture of pyrazole, NaH, and resin-supported phenylboronic acid.  Results will demonstrate this supported-chelate is fully functional.  Active coordination complexes of Cr(III), Cu(II), Co(II), and Rh(I) will be described.  This area of research has great potential to significantly benefit the inorganic discipline and by association, the biochemical, material, and industrial applications it serves

Chasing Trilobites: The Ordovician Period of the Anti-Atlas Mountains

Dennis L. Whitney, Environmental Engineer, American Airlines, Retired

Abstract: During the Ordovician period, which was approximately 490 to 445 million years ago, the Ozark Plateau, which contains Rolla, Jefferson City, and Springfield, was near the equator and on the eastern coast of the North American massif, whereas the Anti-Atlas Mountains of the Northwestern Sahara Desert were also near the equator and on the western shores of Gondwanaland. As a consequence, there is a very good chance that the paleoclimates of these two regions may have been very similar. However, the fossil record indicates that the paleoecology was perhaps dissimilar. Recently, fossil discoveries in the Atlas Mountains have revealed a new and diverse paleoecology. The discovery of this new fossil record has led to new insight into the nature of life in the Ordovician period.

On a recent trip to Morocco, the speaker investigated the quarries, where many of these fossils have been discovered. The new discoveries will be discussed along with their significance to the paelogeography and paleoecology of the Ordovician formations to both the Anti-Atlas Mountains and the Ozark Plateau. The significance of the different paelofaunas of the two regions will be discussed and fossil specimens will be displayed in order to support the discussion.

The comparison of these two paleoecologies indicates that the eastern shore of the North American massif possibly had a different paleoecology than the western shores of Gondwanaland. The fossil record in the Ozarks consists of mostly mollusks, whereas the fossils discovered in the Anti-Atlas Mountains reveal a rich diversity of living creatures, many of which are new to science. These ongoing discoveries are intriguing to scientists and have opened several new avenues of research into the evolution of life. 

 

Colloidal Unimolecular Particles

Sager Gade, Dept. of Chem., MS&T

Abstract: 

Part I. Molecular Weight and Functionality Effects on Colloidal Unimolecular Polymer Formation and Stability

The formation of anionic stabilized colloidal unimolecular polymer, CUP, particles from single polymer strands was investigated as a function of molecular weight.  The CUP particle size was correlated with the absolute molecular weight and its distribution.  The characteristics of the particles were evaluated with respect to viscosity, acid number, size distribution and stability.  The particle size varied from less than three nanometers to above eight nanometers representing polymers with molecular weight in the range of 4,000 to 153,000. Lower molecular weight polymers were found to be unstable due to insufficient ionic stabilization.

Part II. Synthesis of Amino Functional Colloidal Unimolecular Polymer Particles and their Use as Epoxy Curing Agents

The synthesis and utilization of cationic stabilized CUP particles utilizing a low Tg acrylic polymer for the curing of epoxy resins. Copolymer of ethyl acrylate / acrylic acid were synthesized and reacted with aziridine to produce amino modified polymer and hence cationic stabilized CUP particles. This copolymer exhibits cold flow and produce a continuous film. Use of these CUP particles as epoxy curing agents was investigated. 

 

Colloidal Semiconductor Quantum Belts, Platelets, and Magic-size Nanoclusters

William E. Buhro, George E. Pake Professor of Arts & Sciences Chair, Dept. of Chem., Washington University, Saint Louis, MO

Abstract: Pseudo-1D nanocrystals such as quantum wires (QWs) and quantum belts (QBs, nanoribbons) are in principle capable of transporting energy (excitons) and charge over long distances, and thus may have applications in solar-energy conversion and other technologies.  However, excitons and charge carriers in QWs and QBs sample extremely large surface areas and thus have a high probability of encountering surface trap sites, precluding efficient transport.

          I will describe semiconductor QBs in which excitons are efficiently delocalized over the entire length of the nanostructures, and the photoluminescence efficiencies are as high as 40%, rivaling those of quantum rods.  Crystalline, colloidal CdSe quantum platelets (QPs) are prepared at room temperature.  The QBs and QPs are obtained from (CdSe)13 nanoclusters entrained within lamellar-template structures.  Their excellent optical properties result from the smooth facets and effective passivation afforded by the template synthesis, which minimize surface trap-site populations.  The isolation and characterization of [(CdSe)13(n-alkylamine)13] derivatives will also be described.

 

Carbon Dioxide Capture and Hydrocarbon Separations in Metal-Organic Frameworks

Jeffrey R. Long, Materials Sciences Divison, Lawrence Berkely National Laboratory and Dept. of Chem., University of California-Berkeley

Abstract: Owing to their high surface areas, tunable pore dimensions, and adjustable surface functionality, metal-organic frameworks (MOFs) can offer advantages for a variety of gas storage and gas separation applications.  In an effort to help curb greenhouse gas emissions from power plants, we are developing new MOFs for use as solid adsorbents in post- and pre-combustion CO2 capture, and for the separation of O2 from air, as required for oxy-fuel combustion.  In particular, MOFs with open metal cation sites or alkylamine-functionalized surfaces are demonstrated to provide high selectivities and working capacities for the adsorption of CO2 over N2 under dry flue gas conditions.  Breakthrough measurements further show compounds of the latter type to be effective in the presence of water, while calorimetry data reveal a low regeneration energy compared to aqueous amine solutions.  MOFs with open metal cation sites, such as Mg2(dobdc) (dobdc4– = 2,5-dioxido-1,4-benzenedicarboxylate), are highly effective in the removal of CO2 under conditions relevant to H2 production, including in the presence of CH4 impurities.  Redox-active Fe2+ sites in the isostructural compound Fe2(dobdc) allow the selective adsorption of O2 over N2 via an electron transfer mechanism.  The same material is demonstrated to be effective at 45 °C for the fractionation of mixtures of C1 and C2 hydrocarbons, and for the high-purity separation of ethylene/ethane and propylene/propane mixtures.  Finally, it will be shown that certain structural features possible within MOFs, but not in zeolites, can enable the fractionation of hexane isomers according to the degree of branching or octane number.

 

Investigation and Identification of Existing Contaminants in the Environment

Ruipu Mu, Dept. of Chem., MS&T

 

Formal Music Instruction in Grades 5 through 12 Improves Performance in Undergraduate Science and Engineering

Robert Cesario, Dept. of Arts, Languages, and Philosophy, Director of Bands and Orchestras, MS&T

Abstract: 

Introduction. Universities have made efforts to increase capacity to alleviate the shortage of professional nurses, scientists, and engineers. While admission numbers have increased, attrition in undergraduate programs remains high. Stringent admission criteria exist, but educators strive to identify additional criteria that are better individual predictors of success. Filling a limited number of slots with students who are unlikely to succeed expends increasingly sparse resources of time, money, clinical, and laboratory space. Evidence suggests that participation in organized music groups is associated with greater ability in math, reading, cognition, critical thinking, verbal skills, motivation, concentration, confidence, and teamwork. The purpose of this study was to determine if formal music instruction in grades 5 through 12 were associated with improved performance in undergraduate nursing programs and, by extension, presumably science and engineering programs.          

Methods. The anonymous, online, survey examined the following hypotheses. Undergraduate students who participated in organized music instruction in grades 5 through 12 are more likely to (1) graduate from their chosen programs than students who have not had this experience, (2) have higher grade point averages upon finishing their degrees, and (3) do well on subsequent professional exams. In addition, it was hypothesized that there would be a positive relationship between duration of music instruction between grades 5 and 12 and the exit GPA of undergraduate students. For the survey all 78 accredited associate degree, diploma, and baccalaureate level nursing programs in Texas were invited to participate, yielding 306 completed surveys. 

Results. The three hypotheses were supported (p < 0.001). Of those who had graduated from a nursing program, a greater proportion, 64.8 %, had been in some type of organized music program. Graduates who had participated in music programs had average GPAs between 3.5 and 3.79 at graduation; whereas those who were not in music programs had GPAs between 3.0 and 3.19. A greater proportion of those who had been involved in an organized music group obtained their professional qualifications on their first attempt. The study also revealed that GPA correlated positively with number of years of music instruction (p < 0.01).

Conclusions. Organized music participation data is objective, quantifiable, and can be collected quickly and inexpensively as it is readily available on the ACT and SAT student profiles. Music in public schools is available to almost all students in the state of Texas and thereby mediates potential bias of race, ethnicity, or socio-economic status. When selecting students for a limited number of nursing, science, and engineering schools, valid predictive criteria are essential and musical educations seems to be highly useful tool in this regard.

 

General Laboratory Safety Training

Phyllis Lewis, Environmental Specialist, Environmental Health and Safety

Abstract: 

Hazardous Waste Management

  • Federal Regulation & University Policy
  • Types of waste handled by Environmental Health and Safety
    • Chemical, Bio-hazardous, Universal
  • Proper storage of wastes
  • Proper labeling of wastes
  • Filling out the waste pick-up request form
  • Fire Safety (10 minute video)
  • Spill Response

Laboratory Safety

  • General laboratory housekeeping
  • Safety policies
  • Common hazards in the laboratory
    • Chemicals, Bio-hazards, Radiation, Compressed Gas Cylinders
  • Labeling & Storage
  • Chemical inventory:  Chemtrack
  • Personal Protective Equipment
  • Emergency Response

 

Microwave Spectroscopy and the New Millenium: Advancing Technology in Two Directions

Garry S. Grubbs, Dept. of Chem., MS&T

Abstract: Microwave spectroscopy has long been a useful tool for studying and characterizing geometric and electronic structure of gas phase molecules and their interactions. This work describes the construction and implementation of two modern microwave instruments: the cavity Fourier transform microwave (FTMW) and chirped pulse Fourier transform microwave (CP-FTMW) spectrometers. These spectrometers have been equipped with a laser ablation, pulsed supersonic nozzle which allows for the study of many species, both typical and exotic. This technology has also opened the door to spectroscopically study materials useful in creating transistors and microchips in the gas phase with exquisite precision. This can also be used as a tool to investigate typical processes utilized in the manufacturing of these technologies. Specific examples of study and characterization will be discussed.

 

Cancer Biomarkers: From Large to Small Molecules

Prof. Michael Wang, Dept. of Pathology, University of Missouri-Coumbia

Abstract: Life is a self-sustaining chemical process in a given organism.  Cancer is the first killer of human life in medicine.  Although there are great progresses in cancer research and clinical sciences in the past decades, cancer kills approximately 580,000 American citizens and 7.6 million people worldwide each year. From the medical perspective, prevention and early diagnosis of cancer are currently the most feasible solutions to reduce cancer mortality.  In this presentation, I will use lung cancer as an example to discuss the current development of cancer biomarkers, an important tool for early diagnosis of cancer.

     A cancer biomarker can be defined as the biological molecules found in blood or other biofluids or tissues as an indicator of the presence of cancer in the human body. These molecules may be the specific products of cancer cells or a specific response of the body to the presence of cancer.  The molecules may be the mutated DNA fragments, abnormally elevated or reduced mRNA or microRNA, proteins or peptides, and even the small metabolites.  In my lab, we utilize real-time PCRs as a basic methodology to detect DNA mutation, DNA methylation and microRNA levels as biomarkers in patient blood samples for early detection of lung cancer.  We have identified several specific aberrant DNA methylation loci and abnormally elevated microRNA molecules in blood samples that could distinguish early stage of lung cancer patients from non-cancer controls.  The test may be used for lung cancer screening or confirmation in the future. To further increase the sensitivity and accuracy of early cancer detection with an integrated strategy, identifying “oncometabolite” as a new type of cancer biomarker by cancer metabolomic study is a very promising direction. Scientists in chemistry will play a major role for this new discovery.

 

Chemistry Resources in the C.L. Wilson Library

Christopher Jocius, Head of Reference Department C.L. Wilson Library, MS&T

Abstract: An overview of the resources available for chemistry graduate students at the Missouri University of Science and Technology library will be presented. This will include how to access and use the ACS based Scifinder to search the chemical scientific literature.

 

Occurrence and Removal Study of Perchlorate Levels in Missouri Natural and Drinking Waters by Using Ion Exchange Chromatography- Tandem Mass Spectrometry

Danielle West, Dept. of Chem., MS&T

Abstract: Perchlorate (ClO4-) has been utilized for a wide range of purposes: munitions, explosives, solid rocket propellant, pyrotechnics, fertilizers, airbag inflators, fireworks, and other industrial applications. Because perchlorate is highly soluble and chemically inert in water, it can be transported vast distances in groundwater or rivers. Therefore, perchlorate can exist in the natural water and drinking water due to its difficulty to be removed by the current water treatment processes. The US EPA has conducted perchlorate occurrence studies and found perchlorate contamination in both groundwater and surface waters serving as drinking water sources for more than 16 million people in at least 26 states nationwide in USA. Perchlorate has been detected in over 4% of public water systems nationally at the level of greater than or equal to 4 µg/L.  Missouri has large agricultural use of fertilizer, legal use of fireworks, and an U.S. army base, all of which could contribute to perchlorate contamination to our drinking water.  For these reasons, Missouri University of Science and Technology and the Missouri Department of Natural Resources have collaborated in developing a sensitive ion exchange chromatography – tandem mass spectrometry (IC-MS/MS) method for direct analysis of perchlorate without any preconcentration procedures.  The method has been applied to screen for the occurrence level of perchlorate in drinking water at 19 water facilities across the state of Missouri and the removal thereof.

 

An Overview of Patent Law and What to Expect when Preparing and Submitting a Patent

Rebecca Rich, Patent Attorney, Brewer Science Inc., Rolla, MO

Abstract: The patent process can be confusing for scientists, both in industry and academia. This presentation is intended help familiarize you with patent terminology, patent law, and the patent process, and the implications for your research, publications, and potential commercialization. We will cover when filing a patent is appropriate, what to do before your patent is filed, the parts and filing of the patent application, the patent prosecution process, and patent issuance. Patent inventorship, ownership, and rights granted in a patent will be presented, with an emphasis on universities and government-funded research. Recent changes in US patent law will be discussed, as well as an overview of international patent filing. A brief discussion of careers in patent law will be included.

 

Strong Magnetic COupling and Single-Molecule Magnet Behavior in Azophenine Radical-Bridged Dinuclear Complexes

David Harris, Rang Jeon, & Jesse Park, Dept. of Chem., Northwestern University

Abstract: This presentation will describe our efforts to synthesize single-molecule magnets with well-isolated spin ground states by employing radical bridging ligands. In particular, a series of dinuclear metal complexes of the bridging ligand azophenine has been synthesized. Chemical reduction of the iron congener affords a one-electron-reduced species. X-ray diffraction and Mössbauer spectroscopy confirm that the reduction occurs on azophenine to give an S= 1⁄2 radical bridging ligand. Dc magnetic susceptibility measurements demonstrate the presence of extremely strong direct antiferromagnetic exchange between S = 2 Fe(II) centers and azophenine radical in the reduced complex, giving an S = 7/2 ground state with an estimated coupling constant magnitude of |J| ≥ 900 cm–1. Mössbauer spectroscopy and ac magnetic susceptibility reveal that this complex behaves as a single-molecule magnet with a spin relaxation barrier of  Ueff = 50(1) cm–1. To our knowledge, this complex exhibits by far the strongest magnetic exchange coupling ever to be observed in a single molecule magnet.

 

Molecular Models for the Study of Spin Relaxation and Magnetic Anisotropy

Danna Freedman, Dept. of Chem., Northwestern University

Abstract: Quantum computation has the potential to break the most commonly employed encryption scheme and to accurately simulate quantum systems. For these reasons quantum computation is a highly active area of research with numerous qubit candidates proposed thus far. Intuitively, electronic spin can behave in a quantum fashion, therefore could serve as a candidate qubit. Yet thus far research in the area has been hampered by rapid spin decoherence. While synthetic chemists are adept at designing molecules with the ideal spin manifold the design principles for the synthesis of molecules with long coherence time have not been established. Research demonstrating progress towards the first set of unifying principles for quantum computation will be presented with future directions in employing these design principles to synthesize new candidate qubit molecules.

 

Ethical Writing and the Graduate Student

Elizabeth Roberson, Technical Editor, Office of Graduate Studies, MS&T

 

Investigation of Fluid Flow Behavior in Nano-scale Channels Using Single Molecule Imaging System

Qihua Wu, Dept. of Chem., MS&T

Abstract: Many of unconventional tight gas reservoirs contain micro-scale or even nano-scale pores and channels, which are significantly different from conventional reservoirs. However, the fluid flow behavior in the nano-scale pores and channels is not well understood. In this study, a lab-on-chip approach for direct visualization of gas/water two phase flow behavior in nano-scale channels is presented. The nanofluidic-chips were designed and fabricated, and experiments of two phase flow in nano-scale channels with various depths were conducted. Images were captured by using epi-fluorescence microscopy method. The fluids velocities and pressure drop in the nano-scale channels were recorded and flow patterns were characterized. Three different flow patterns, single, annular and stratified flow were observed and their special features are described. Flow regime map was summarized and compared with results in conventional-size channels.

The drainage/imbibition processes in the nano-scale channels were also investigated. The residual saturations of gas or water in the nanochannels with different dimensions were compared. This work provides valuable information for better understanding the single and two phase flow behavior in the nano-scale channels. This study was financially supported by Research Partnership to Secure Energy for America (RPSEA).

Structural, Electronic, and Catalytic Properties of Metal Complexes Bearing "P-N-P" Ligands

Prof. Panayotis Kyritsis, Dept. of Chem., National and Kapodistrian University of Athens, Athens, Greece

Abstract: A common theme in structural bioinorganic chemistry is the presence of sulfur-containing ligands in the active site of metalloenzymes, most commonly in the form of cysteine thiolate (RS-). Very rarely, Cys is replaced by selenocysteine, Se(Cys).

Synthesis of M(II)L2 complexes (M = Mn, Fe, Co, Ni, Cu), with “P-N-P”-type of bidentate LH ligands R2P(E)NHP(E)R2 (E = S, Se; R = Ph, iPr), affords M(II)E4 metal sites with either tetrahedral or square-planar geometry.1-3 That series of complexes was recently extended to include octahedral complexes of the general formula: [M{(OPPh2)(EPPh2)N}2(sol)2], M = Mn, Co, Ni; E = S, Se; sol = dmf, thf, dmso.4 All those tetrahedral and octahedral complexes are paramagnetic, and therefore amenable to physicochemical methods that directly probe the magnetic centers. Recent investigations by Electron Paramagnetic Resonance spectroscopy, as well as their implications for the active sites of specific metalloproteins, will be discussed.5-7

“P-N-P”-type ligands have been also employed for the synthesis of Rh(I), Ni(II) and Pd(II) complexes, showing activities towards hydroformylation,8 polymerization9 and C-C coupling reactions,10 respectively. With proper design of the “P-N-P” ligand framework, such catalysts can be immobilized onto silica, mesoporous molecular sieves and clay solid supports, affording active heteregeneous catalytic systems.

 

Geological Indicators of Earth's Climatic Conditions in the Past

Prof. Wan Yang, Dept. of Geological Sciences and Engineering, MS&T

Evolution of General Chemistry Instruction at MS&T

Travis McDowell, Dept. of Chem., MS&T

Abstract: During the last seven years the general chemistry course at Missouri S&T has undergone many changes to better serve the ever-changing incoming student body.  At this point, nearly every aspect of the course has undergone adjustments.  These adjustments have been necessary to facilitate an improved learning experience for the students and maintain relevance due to the growing list of alternatives for student learning.  On the learning side of things, changes made were to improve student communication, information delivery, the assessment methods employed.  With regards to all changes other factors, such as minimizing the cost of operation while also maximizing the time efficiency of graduate students and faculty involved, were observed.   

New Quantitative NMR Techniques for Determining the Product Yield of Hydrothermal Biomass

Lingyu Chi, Dept. of Chem., MS&T

Abstract: Hydrothermal biomass-to-fuel reactions are a viable pathway for generating liquid biofuels. Newly developed, quantitative HNMR techniques are employed to identify reaction intermediates, understand the mechanisms, and study the kinetics of hydrothermal biomass reactions. The investigations are carried out in a 5-mm NMR tube with a 1-mm capillary tube insert filled with an integration reference standard, so that the aqueous sample drawn from the reactive solution is isolated from the D2O lock and the external integration and chemical-shift reference. The external integration reference standard can be used to accurately report mass percentages of biomass reaction products. This presentation will identify some of the practical aspects pertaining to HNMR-based quantitative analysis and highlights some of the limitations, uncertainties, and applications of this particular approach to the analyses of biomass reaction products.

2014

General Laboratory Safety Training

Phyllis Lewis, Environmental Specialist, Environmental Health and Safety

Abstract: 

Hazardous Waste Management

  • Federal Regulation & University Policy
  • Types of waste handled by Environmental Health and Safety
    • Chemical, Bio-hazardous, Universal
  • Proper storage of wastes
  • Proper labeling of wastes
  • Filling out the waste pick-up request form
  • Fire Safety (10 minute video)
  • Spill Response

Laboratory Safety

  • General laboratory housekeeping
  • Safety policies
  • Common hazards in the laboratory
    • Chemicals, Bio-hazards, Radiation, Compressed Gas Cylinders
  • Labeling & Storage
  • Chemical inventory:  Chemtrack
  • Personal Protective Equipment
  • Emergency Response

 

N-acetylcysteine Amide, a Thiol Antioxidant that Prevents Bleomycin-induced Toxicity

in Human Alveolar Basal Epithelial Cells

Maria Fan, Dept. of Chem., MS&T

Abstract: Bleomycin (BLM), a glycopeptide antibiotic from Streptomyces verticillus, is an effective antineoplastic drug. However, its clinical use is restricted due to the wide range of associated toxicities, especially pulmonary toxicity. Oxidative stress has been implicated as an important factor in the development of BLM-induced pulmonary toxicity. Previous studies have indicated disruption of thiol-redox status upon BLM treatment. Therefore, this study focused on (1) investigating the effects of BLM on A549 cells and (2) elucidating whether N-acetylcysteine amide (NACA) provides any protection against BLM-induced toxicity.  Oxidative stress parameters, such as glutathione (GSH), malondialdehyde (MDA), and antioxidant enzyme activities were altered upon BLM treatment. Loss of mitochondrial membrane potential, as assessed by fluorescence microscopy, indicated that cytotoxicity is possibly mediated through mitochondrial dysfunction. Pretreatment with the thiol antioxidant NACA reversed the oxidative effects of BLM. NACA decreased the reactive oxygen species (ROS) and MDA levels and restored the intracellular GSH levels. Our data showed that BLM induced A549 cell death by a mechanism involving oxidative stress and mitochondrial dysfunction. NACA had a protective role against BLM-induced toxicity by inhibiting lipid peroxidation, scavenging ROS, and preserving intracellular GSH and mitochondrial membrane potential. NACA can potentially be developed into a promising adjunctive therapeutic option for patients undergoing chemotherapy with bleomycin.

 

 

Electrokinetic and Rheological Study of CUPs

Ameya Natu, Dept. of Chem., MS&T

 

Mechanism Study of Zine Oxide Nanoparticles Cytotoxicity

Qingbo Yang, Dept. of Chem., MS&T

Synthesis, Characterization, and Application of Hydroxyl Acid Capped Oligopeptides as a Selective Substrate in a Trypsin Inhibitor Assay

Jinyu Du, Dept. of Chem., MS&T

Applications of Solid State NMR

Prof. Dewey Barich, Dept. of Chem., University of Kansas

Abstract: Solid State NMR (SSNMR) is a powerful analytical technique that offers multiple investigative avenues for studying a wide range of materials and properties.  Materials as varied as fine organics, catalysts, soils, lignins, carbonaceous materials, minerals, and biological materials have been studied using SSNMR.  This seminar will present several examples including quantitation of physical forms, structural information of complex materials, and conformational detail in crystalline materials.

 

Aerogels as Diverse Nanomaterials

Abhishek Bang, Dept. of Chem., MS&T

Abstract: 

A. Polyurea-crosslinked dysprosia aerogels for drug delivery applications. Aerogels are promising materials as multifunctional drug delivery carriers. In this context, we investigated bio-compatible polymer-crosslinked dysprosia (X-DyOx) aerogels as drug delivery vehicles and demonstrated storage and release of paracetamol, indomethacin and insulin in phosphate buffer (pH = 7.4) or 0.1 N HCl (pH = 1) at 37 OC. As controls we used: (a) orderly-mesoporous silica (n-SiOx-MP4-T045), (b) macroporous polymer-crosslinked silica (X-SiOx-MP4-T045),and (c) randomly mesoporous polymer-crosslinked amine-modified silica (X-TMOS-co-APTES) aerogels. Drug uptake was significantly higher with X-DyOx (up to 35% w/w) relative to n-SiOx-MP4-T045 and X-SiOx-MP4-T045 (16-19% w/w), and was comparable to that of X-TMOS-co-APTES aerogels (up to 30% w/w). X-DyOx aerogels have shown much slower release rates (100% release in ~60 h) than their counterparts, whereas very fast to moderate drug release behavior was observed (100% release in 0.5 to 24 h). Considering that dysprosia is strongly paramagnetic, hence, can be focused magnetically, and can be also neutron-activated, X-DyOx-based materials have the potential of becoming multifunctional drug delivery vehicles.

B. Flexible polyurethane-acrylate aerogels for thermal insulation and environmental remediation. Flexible aerogels are particularly attractive materials for thermal insulation of sub-sea oil pipes, cryogenic tanks and oil-spill absorption, whereas a high degree of foldability is desirable. Herein, we report flexible aerogels via polyurethane-acrylate chemistry. For this, we designed a star shape monomer possessing urethane linkages of a triphenylmethane core with acrylate moieties. For comparison reasons, ethylene glycol dimethacrylate or 1,6-hexanediol diacrylate are used as variable length chain extenders, and their effect on the material properties of the resulting polyurethane-acrylate aerogels was investigated. Lower density polyurethane-acrylate aerogels (~0.14 g cm-3)were macroporous and flexible (by 3-point bending test), while higher density samples (0.66 g cm-3) were rigid and mechanically strong (by compression testing). Those properties were independent of the chain length of the extender, pointing to a nanoscopic origin for their flexibility, rather than to a molecular one.

C. Polydicyclopentadiene (pDCPD) aerogels: Nanostructure control via ring opening metathesis polymerization (ROMP) induced with Grubbs catalysts I and II.  pDCPD polymers synthesized via ROMP are emerging as attractive materials for diverse applications ranging from separation media to body armor. They are synthesized from readily available dicyclopentadiene (DCPD), an inexpensive byproduct of petroleum refinery. Here, we developed pDCPD-based aerogels using two different Grubbs catalysts (GC-I and GC-II) with different catalytic activity towards ROMP. pDCPD based wet-gels synthesized from GC-II show excessive swelling in toluene (up to 200% v/v) followed by de-swelling and uneven shrinkage in acetone, resulting in severely deformed aerogels. However, wet-gels using GC-I retain their shape throughout processing. Percent crosslinking calculated via solid state 13C NMR shows that GC-II-catalyzed pDCPD aerogels undergo only 4-5% crosslinking as compared to 17-23% when GC-I is used. Microscopically, pDCPD aerogels derived from GC-I and GC-II catalysts show different morphology (fibrous and particulate, respectively).

General Laboratory Safety Training

Phyllis Murphy, Environmental Specialist, Environmental Health and Safety

Abstract: 

Hazardous Waste Management

  • Federal Regulation & University Policy
  • Types of waste handled by Environmental Health and Safety
    • Chemical, Bio-hazardous, Universal
  • Proper storage of wastes
  • Proper labeling of wastes
  • Filling out the waste pick-up request form
  • Fire Safety (10 minute video)
  • Spill Response

Laboratory Safety

  • General laboratory housekeeping
  • Safety policies
  • Common hazards in the laboratory
    • Chemicals, Bio-hazards, Radiation, Compressed Gas Cylinders
  • Labeling & Storage
  • Chemical inventory:  Chemtrack
  • Personal Protective Equipment
  • Emergency Response

Recent Advances on Pebble Bed Nuclear Reactor Dynamics by Developing Advanced Measurement and Computational Techniques

Prof. Muthanna Al-Dahhan, Dept. of Chemical and Biochemical Engineering, MS&T

Structure-Property Studies in Photoresponsive Cyanometalates

Stephen M. Holmes, Dept. of Chem. & Biochem., UMSL

Polyacrylamide Microgels via Water-Free Inverse Emulsion Polymerization

Zun Chen, Dept. of Chem., MS&T

 Abstract: Crude oil is an internationally important commodity raw material for energy and chemical industries. After primary, by natural pressure, and secondary, by water and gas driven, stages of oil recovery from a well field source, more than two thirds of the original oil remain in the reservoir. In these tertiary reservoirs, the directly water- or even polymer-flooding assisted recovery of reservoir resources are not efficient for displacing resource fluid due to severe heterogeneity of the geologic formations.  The displacing agents, e.g., water, prefer low resistance wide pore channel flow of low pressure resistance compared to narrow pore, high pressure resistance flow. Therefore, excess water production becomes a major problem, which leads to early abandonment of otherwise unrecoverable hydrocarbon resources. To solve this problem, polymer gel treatments of the injection wells are being developed to preferentially limit flow through the ‘thief’ zones.  Polymer gels can be cost-effective methods to improve sweep efficiency to reduce excess water production during oil recovery. We describe a novel polyacrylamide microgel synthesis by a pseudo-inverse emulsion polymerization in the absence of water. Two different crosslinkers are employed in this study to give the particle ‘smart’ properties, e.g., 2 stages of size expansion that are temperature sensitive. When put into water, the original dry particle can swell by as much as 25 times in size under low temperature (e.g., 40 ? C).  Exposure to a harsh reservoir environment, for instance, the stimuli of high temperature (e.g., 90 ? C), can induce cleavage of one of the two crosslinking types to enable further expansion. The microgel access to targeted pore channels is thus controlled to realize changes in the reservoir flow profile within the geologic formation.

Conversion of Electrodeposited Co(OH)2 to CoOOH and Co3O4 and a Comparison of their Catalytic Activity for the Oxygen Evolution Reaction

Ying-Chau Liu, Dept. of Chem., MS&T

Accelerating Functional Genomics Using Mass Spectrometry

Dr. Trent R. Northen, Lawrence Berkeley National Laboratory, Berkely, CA

Abstract: Microorganisms exhibit complex metabolism and metabolic interactions with their environment, large parts of which remain unknown. Deficiencies in functional annotations of microbial genomes as well as incomplete knowledge of small molecule repertoires (metabolomes) of microorganisms limit the understanding of their metabolism. This talk will introduce mass spectrometry based metabolomics and approaches to link these to microbial genomics. Including recent work connecting genes to the utilization of specific metabolites in bacteria by profiling metabolite utilization in libraries of mutant strains. Here, untargeted mass spectrometry-based metabolomics was used to identify metabolites utilized by soil microbes. Targeted high-throughput metabolite profiling of spent media of 8042 individual mutant strains was performed to link utilization to specific genes. Using this approach we identified genes of known function as well as those required for the metabolism of ‘novel’ metabolites. This work is being extended for the high throughput characterization of novel natural products using acoustic printing of nanoliter volumes coupled to nanostructure initiator mass spectrometry (NIMS). 

Chromic Phenomena- Reversible Color Change Chemistry

Dr. Harlan J. Byker, Chief Executive Officer, Pleotint, LLC

Abstract: Electrochromic, thermochromic, and photochromic technologies have been used in many intensive and expensive attempts at commercial product development over the last 50 years. The chemistry and materials behind chromic technologies are described and a discussion of the commercialization attempts is given. A particular focus is given to the use of thermochromic materials for sunlight responsive, dynamic, energy saving windows which are now starting to be commercialized.

The Challenges and the Fun of Internal Rotation in Rotational Spectroscopy

Dr. Peter Groner, Dept. of Chem., UMKC

Abstract: Internal rotation and other large-amplitude motions (LAMs) in molecules affect rotational, vibrational and electronic energy levels and their respective spectra. Manifestations of the interactions between internal rotation and these other degrees of freedom are the appearance of spectra of conformers and shifts or splittings of spectral lines. A short review of the basics of rotational and vibrational spectroscopy is followed by explanations and illustrations of these effects. They become more interesting and more challenging in the presence of two or more LAMs. Significant progress has been made over the last two decades in instrumental and experimental techniques (sensitivity, resolution), data analysis and theoretical developments to study and understand the effects of internal rotation. For molecules with one or two methyl group internal rotors, it is now possible most of the time to assign and fit thousands of spectral lines to experimental precision and to high rotational quantum numbers. Thorough analysis of spectra may provide information about torsional potential functions, heights of barriers to internal rotation, and conformational energy differences. Barriers determinable by rotational spectroscopy are lower than barriers determinable by NMR. The spectroscopy of molecules with internal rotation has found applications in radio-astronomy and the planetary sciences.

 

New Cathode Materials for Li-ion Batteries

Hooman Yaghoobnejad Asl, Dept. of Chem., MS&T

Abstract: Li-ion batteries play an essential role for powering-up a variety of equipment, from small portable electronic devices to heavy Electric vehicles (EVs). Research and development in this field is actively proposing new and alternative chemistries in cathode design from transition metal oxides in the first generation of these batteries to polyanion-based (PO4, SO4, SiO4, and BO3/BO4) compounds. In this context we are utilizing new synthesis routes to make novel compounds with combinations of different polyanions and transition metal compounds. The advantage of using polyanions rather than pure oxide in cathode composition is the added safety feature that comes from the strong covalency between the oxygen atom and the central main group element (P, S, B, or Si) in the polyanion. The presentation will focus on three new compositions Li3Fe2(HPO3)3Cl, LiFePO4NO3 and LiFeB(PO4)2(H2O)2, recently discovered in our laboratory that show promising electrochemical activity for Li-ion battery. The details of synthesis, structure determination employing X-ray diffraction (single-crystal and powder) and results of electrochemical studies in Li-ion cells towards reductive lithiation and oxidative delithiation will be discussed. This presentation will also cover how fluoride substitution can tune the cell voltage in a particular structure type, namely tavorite, LiFePO4(OH)xF1-x where 0≤x≤1. In the conclusion a discussion relating the structure to the cell performance and also a comparison with some of other known cathode materials will be presented.

Innovative Applications of Polymeric Materials in Microelectronic Devices- An Overview of Brewer Science Technologies

Dr. Tony D. Flaim, Brewer Science Inc., Rolla, MO

 

Synthesis and Characterization of Vanadium Oxide Nanomaterials for Li-ion Battery Cathodes

Tyler Fears, Dept. of Chem., MS&T

 

Effects of the Novel Thiol Antioxidant N-acetylcysteineamide Eyedrops on Reversing Sodium Selenite-induced Cataracts in Wistar Rats

Sri Krishna Yasaswi Maddirala, Dept. of Chem., MS&T

The Design and Application of a TPD Based Photorefractive Composite to Aberrated Image Restoration

Yichen Liang, Dept. of Chem., MS&T

Abstract: Organic photorefractive (PR) material has shown its considerable potential in practical applications due to its high figure of merits including low fabrication-cost, possibility of properties tuning by changing its composition and faster response time, etc [1]. In our approach, [1,1’-Biphenyl]-4.4’-diamine-N,N’-bis(3-methylphenyl)-N,N’-diphenyl (TPD) was used as the charge transfer matrix for the PR composite due to its high value of charge mobility among organic charge transporting materials. In addition, C60 and 4-azacycloheptylbenzylidene-malononitrile were included in the composites as photo-sensitizer and nonlinear chromophore, respectively. To improve the performance of PR material, quantum dots (QDs) were doped inside the composites, which results in a dramatic improvement of response time. By surface modification process, a charge transfer ligands capped QDs were synthesized and it showed a significant enhancement of photoconductivity in the TPD based composites. The designed PR material has shown its ability in phase aberration elimination. This demonstrates the value of PR material in optical communication applications.

 

 

2015

Theoretical Tools to Study Dynamics of Planetary Atmospheres

Moumita Majumder, Dept. of Chem., MS&T

Abstract: The evolution of planetary atmospheres speaks to the history of the creation of the universe. The physical and chemical environments of planetary atmospheres vary greatly between different planets, moons and other celestial objects. The types of life found on Earth rely on a limited range of conditions. Understanding the physical and chemical behavior of atmospheres requires tools to treat collisional reaction dynamics in the gas phase. This talk presents methods to compute accurate potential energy surfaces needed to predict the spectroscopy and dynamics of small species.

Quantum Dynamics of Small and Medium Sized Molecules: Applications to Atmospheric Chemistry, Astrophysics, and Combustion

Steve Ndengue, Dept. of Chem., MS&T

Simultaneous Determination of Additives and Contaminants for a Comprehensive Characterization of Dielectric Fluids

Carlo M. Roggero, Dept. of Chem., MS&T

DNA Engineering: from Structure to Application

Risheng Wang, Dept. of Chem., MS&T

Abstract: Deoxyribonucleic acid (DNA) is the carrier of generic information in living cells, which can replicate itself through Watson-Crick base paring.  Over the past three decades, researchers in the emerging field of DNA nanotechnology are using the DNA as structural nanomaterials to build addressable artificial nanostructures in one, two and three dimensions. These self-assembled nanostructures have been used to precisely organize functional components into deliberately designed patterns which have a wide applications in material science, biomedical, electronic and environmental fields. The development of DNA nanotechnology and its potential application will be covered.  Then my talk will discuss the design and construction of several DNA nanostructures including: self-assembly of DNA six-helix nanotubes from two half-tube components; Using DNA origami template to organize semiconducting quantum dots (QDs) and gold nanoparticles (AuNPs) and discussing the methods to integrate “top-down” nanofabrication technique with “bottom-up” self-assembly. 

Constructing Global Potential Energy Surfaces

Phalgun Lolur, Dept. of Chem., MS&T

 

In Vitro Study of Wound-healing Capabilities of Bioactive Glass Nanofibers under Various Culture Conditions

Sisi Chen, Dept. of Chem., MS&T

 Abstract: Bioactive glass materials have been developed and widely used for biomedical applications such as hard or soft tissue repair and regeneration. Recently developed borate-based, nanometer-scale, fiber-shaped glasses integrated many promising features and study results have shown that borate bioglass can promote both osteogenesis and angiogenesis, and thus triggered increasing interest in future wound-healing applications especially on soft tissues. However, the underlying biochemical mechanism is still largely unknown. In this study, three different micro- or nano-fibers, one silicate-based (45S5) and one bioactive borate glasses (13-93B3), and one copper/zinc (Cu/Zn) doped borate glass (1605), were examined to investigate their stimulation of vascular endothelial growth factor (VEGF) under varied culture conditions. An in vitro dynamic flow control system that mimics the niche environment of the vascular depletion and hyperplasia area in wound-healing regions was used to demonstrate the actual biological compatibility and functionality of the borate glass nanofibers. Cell growth and the secretion of VEGF were monitored along with the release of boron and other nanofiber constituents. The detailed experimental conditions and results under both static condition and dynamic flow condition will be presented and discussed at the seminar.  

 

Terrestrial and Extraterrestrial Studies of Nonexistent Compounds

Dennis J. Clouthier, Dept. of Chem., University of Kentucky

 Abstract: Powerful laser-based techniques have been developed over the last two decades for detecting transient and very reactive molecules in very low concentrations. With these methods we have been able to thoroughly characterize species which had previously been classified as "nonexistent" and unlikely to be observable. This talk will describe the technology and experimental techniques for preparing and studying such compounds including our first determination of the length of the carbon-silicon triple bond and the detection of a new phosphorus carbide in the laboratory and in outer space. Practical applications in the characterization of semiconductor growth intermediates, upper atmospheric chemistry, and the chemistry of the interstellar medium will also be discussed.  

 

Biomarker Discovery and Detection for Early Cancer Detection

Casey F. Burton, Dept. of Chem., MS&T

  

 

An Introduction to the Field of Explosives and Pyrotechnics

John Bowles, UTEC Corporation, Riverton, KS

  

 

Toward Automating Two-Dimensional Electrophoresis- a Hybrid Chip Devise for Protein/Peptide Separation

Prof. Shaorong Liu, Dept. of Chem. & Biochem., University of Oklahoma

Abstract: In this presentation, we introduce a chip-capillary hybrid device to integrate capillary isoelectric focusing (CIEF) with parallel capillary sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS-PAGE) or capillary gel electrophoresis (CGE) toward automating two-dimensional (2D) protein separations. The hybrid device consists of three chips that are butted together. The middle chip can be moved between two positions to re-route the fluidic paths, which enables the performance of CIEF and injection of proteins partially resolved by CIEF to CGE capillaries for parallel CGE separations in a continuous and automated fashion. Capillaries are attached to the other two chips to facilitate CIEF and CGE separations and to extend the effective lengths of CGE columns. Specifically, we illustrate the working principle of the hybrid device, develop protocols for producing and preparing the hybrid device, and demonstrate the feasibility of using this hybrid device for automated injection of CIEF-separated sample to parallel CGE for 2D protein separations. Potentials and problems associated with the hybrid device are also discussed.

Untitled I

Stephanie L. Brock, Dept. of Chem., Wayne State University

 

Cytotoxicitiy is a Function of Multiple Chemical and Physical Properties of Engineered Nanomaterials

Prof. Yue-Wern Huang, Dept. of Biological Science, MS&T

 Abstract: It is estimated that by 2017, this field will represent a $48.9 billion market. As engineered nanoparticles (NPs) currently occupy a significant portion of the market and are anticipated to proliferate commercially, there is an urgent need to study their potential impact on human health and the environment.  In this seminar, I will present information with regard to what physicochemical properties of nanomaterials influence cytotoxicity. The properties investigated include band-gap energy, surface charge, relative available particle surface binding site, and metal dissolution. Furthermore, I will also present our recent findings in altered cell cycle and inhibition of cell proliferation. Collectively, this information could inform design of safer engineered nanomaterials.

Give Vitamin E Another Chance

Prof. Nukhet Aykin-Burns, Division of Radiation Health UAMS-College of Pharmacy, Little Rock, AR

 Abstract: Radiation therapy is frequently used to treat malignant conditions either alone or concomitant with other modalities. 95% of patients who have had radiotherapy suffer from both acute and chronic side effects. Thus, despite discoveries in radiation biology and improvements in radiation technology, there is still a significant need for a safe and effective radio-protector/radiomitigator compound to alleviate the side effects of radiotherapy on normal tissues.

Among the few most promising alternatives are the vitamin E analogs δ-tocotrienol (DT3) and g-tocotrienol (GT3). These compounds have shown significant radioprotectant and radiomitigator activities with minimal side effects. However, the expense of purification limits their potential use.  Two inexpensive natural sources with abundant tocotrienol content have shown protection against radiation induced mitochondrial dysfunction and oxidative stress in human cells and in a murine model, suggesting they are viable sources for tocotrienols that can be used as radioprotectors.

General Laboratory Safety Training: Safety

Environmental Health and Safety, MS&T

 Abstract: 

  • General Safety
    • Environmental Health and Safety Department
    • General Rules/Policies and Prudent Practices
    • Fire Safety
    • Emergency Response
    • Hazard Communication
    • Engineering/Administrative Controls, and Personal Protective Equipment
    • Injury / Incident Reporting
  • Hazardous Material Safety and Management
    • Chemical/Biological/Radiological Hazards
    • Compressed Gas Cylinders / Cryogenics
    • Physical Hazards
    • Chemtrack Inventory System

General Laboratory Safety Training: Environmental Compliance

Environmental Health and Safety, MS&T

 Abstract: 

  • Environmental Management System
    • ISO 14001
    • Corrective action
  • Hazardous Waste Management
    • Federal Regulations
    • Chemical Waste – proper storage and labeling
    • Chemical Waste – pick-up request
    • Biological Waste
    • Universal Waste
    • Spill Response

Continuous Flow Reactor for Carbonic Acid Hydrolysis of Biomass

Nicholas Dudenhoeffer, Dept. of Chem., MS&T

 Abstract: The increasing need for renewable fuels sources has led to the investigation of different methods that can maximize the bioethanol production from the fermentation of carbohydrate-rich biomass.

      The two most commonly used hydrolysis methods for carbohydrate-rich biomass are enzymatic hydrolysis and mineral acid hydrolysis.  However, enzymatic hydrolysis is a slow process and mineral acid hydrolysis requires neutralization and generates a waste stream.  In this study high temperature water and carbonic acid was used as an alternative to the common mineral acid hydrolysis.  Unlike mineral acids, carbonic acid generated from dissolved CO2 does not require neutralization and eliminates the production of waste. A high pressure continuous flow reactor designed for the treatment of wet biomass using pressurized carbon dioxide was used for the hydrolysis of microalgae biomass. The reaction conditions such as resident time and temperature were optimized for the formation of simple sugars and degradation byproducts.  The yield of simple sugars from the direct treatment of whole biomass for 5 minutes reaction at 210°C using 7 MPa CO2 was very low, but increased to levels similar to the dilute mineral acid hydrolysis when a small amount (0.05%) of sulfuric acid was added.  The amount of thermal degradation byproducts such as 5-HMF and furfural was approximately one order higher, however, no inhibition was observed during the subsequent fermentation of hydrolysis substrates to ethanol. 

 

Applications of Single Particle Inductively Coupled Plasma-Mass Spectrometry

Yongbo Dan, Dept. of Chem., MS&T

 

From Standard NMR Relaxation Experiments to High-resolution Relaxometry

Klaus Woelk, Dept. of Chem., MS&T

 

Nanostructured Catalysts Prepared by Atomic/Molecular Layer Deposition

Xinhua Liang, Dept. of Chemical & Biochemical Engineering, MS&T

Abstract: Catalysts are responsible for the production of over 60% of all chemicals and are used in some 90% of all chemical processes worldwide. Heterogeneous catalysts enable many chemical transformations of fossil resources (natural gas, methane, liquid petroleum, coal, etc.) into useful products. Normally, heterogeneous catalysts consist of small metal particles dispersed on a high surface area porous oxide support. Traditional methods, such as wet-chemical processing, can produce metal particle catalysts as small as several nanometers, but these methods cannot precisely control the size of the catalytic nanoparticles and disperse them homogeneously within the porous substrates. In addition, heterogeneous catalysts cannot selectively convert specific molecules in the reactant mixture to catalyze only desired reactions. Novel approaches are required to synthesize and characterize stable metal nanoparticles catalysts with tightly controlled sizes to further advance the knowledge of their unique size-dependent catalytic behavior. Recently, atomic layer deposition (ALD) has been used to prepare highly active, highly dispersed metal nanoparticles. ALD is a thin film growth technique based on sequential, self-limiting surface chemical reactions, and has focused principally on the formation of thin film oxides with precise atomic layer control. Molecular layer deposition (MLD), which is similar to ALD, can be utilized to deposit pure polymer films or hybrid organic/inorganic polymer films using suitable precursors. Highly porous metal oxide films with well-defined porous structures and precisely controlled thickness down to several angstroms can be prepared from dense organic/inorganic hybrid metal alkoxide films grown by MLD. These ultra-thin films can be used for catalyst encapsulation. In this presentation, I will introduce ALD/MLD chemistry, particle surface functionalization by ALD/MLD, and examples of nanostructured catalysts prepared by ALD/MLD, such as thermally stable size-selective catalysts.

 

Introducing a Blended Laboratory Component in the General Chemistry Course

Shayna B. Burchett, Dept. of Chem., MS&T

 

Accelerated Discovery of Materials 

Prof. Kenneth Poeppelmeier, Dept. of Chem., Northwestern University 

 

The Chemistry Set Revisted after Fifty Years

Dennis Whitney, American Airlines, Retired

 

Engineered Nanostructures for Regulation and Investigation of Cellular Signaling Processes

Prof. Gang-yu Liu, Dept. of Chem., University of California, Davis

 

Conversion of Glasses into Biologically Useful Products

Prof. Mohamed N. Rahaman, Dept. of Materials Science & Engineering Director, Center for Biomedical Science and Engineering, MS&T

Abstract: There is growing interest in glasses for use in healthcare. Glasses have the advantage of ease of fabrication and compositional modification. The reactivity of a glass can be controlled over a wide range, from nearly inert to highly reactive, by controlling its composition. While bioinert glasses are used in some medical applications, glasses that react in an aqueous solution such as the body fluid (referred to as bioactive glasses) are There is growing interest in glasses for use in healthcare. Glasses have the advantage of ease of fabrication and compositional modification. The reactivity of a glass can be controlled over a wide range, from nearly inert to highly reactive, by controlling its composition. While bioinert glasses are used in some medical applications, glasses that react in an aqueous solution such as the body fluid (referred to as bioactive glasses) are receiving more research and development interest for medical and dental applications. Bioactive glasses degrade and convert to hydroxyapatite (the mineral constituent of bone) in an aqueous phosphate solution such as the body fluid, releasing ions in the process which can stimulate the gene expression of cells and, thus, enhance bone regeneration and soft tissue healing. The reaction of certain glasses in a phosphate solution can also be used to create phosphate materials near room temperature which have unique architectures, such as hollow hydroxyapatite microspheres being researched for drug and growth factor delivery. This presentation will describe methods for creating biomedical glasses and converting them into a variety of compositions and architectures for use in applications such as bone regeneration, wound healing and drug delivery.   

 

How Chemistry Promotes Modern Medical Imaging: a Bench-to-Bedside Story about Chemical Exchange Saturation Transfer MRI

Prof. Guanshu Liu, Kennedy Krieger Institute & Russel H. Morgan Dept. of Radiology and Radiological Science, John Hopkins Medical School

Abstract: MRI has become one of the most important medical imaging modalities and is playing indispensable roles in the diagnosis and treatment of many diseases. MRI detection can be further advanced from the anatomical level to the molecular level, with the help of specific molecular probes.  Recently, along with the development of MR molecular imaging, Chemical Exchange Saturation Transfer (CEST) has emerged as an attractive MRI contrast mechanism. The CEST MRI contrast is generated simply by transferring the modulated magnetization from water-exchanging protons (OH, NH, or NH2) to their surrounding water molecules (the source of MRI signal), which makes it possible to directly use MRI to detect many diamagnetic molecules in as low as mM concentration range. Thus CEST opens a new gate to accomplish MR molecular imaging with biodegradable and biocompatible compounds, including those already approved for clinical use and even many endogenous biomolecules.  In this talk, a brief introduction of CEST MRI mechanism will be first provided, followed by several examples showing its biomedical applications, which are either being tested or ready to be used in the clinic.  The importance of chemistry in the development of modern MR imaging will be then discussed.

Taking the Best of Two Worlds: A Combined Experimental and Computations Study of New Materials

Vadym Mochalin, Dept. of Chem., MS&T

 

Functional Nanoporous Polymeric Aerogels: Polyurea and Polyamides

Malik Adnan Saeed, Dept. of Chem., MS&T

 Abstract:

Part A: Nanoporous Polyurea from Triisocyanates Reacting with Mineral Acids

     Isocyanates react with carboxylic acids and yield amides. What is reported herewith is that transferring that reaction to a range of mineral acids, (anhydrous H3BO3, H3PO4, H3PO3, H2SeO3, H6TeO6, H5IO6 and H3AuO3) yields urea. The model system for this study was a triisocyanate, tris(4-isocyanatophenyl)methane (TIPM), reacting with boric acid in DMF at room temperature yielding nanoporous polyurea networks that were dried with supercritical fluid CO2 to robust aerogels. Residual boron in the model system was quantified with prompt gamma neutron activation analysis (PGNNA). It was found very low (≤0.05 % w/w) and was shown to come primarily from B2O3 (by 11B NMR). Thus, any mechanism for systematic incorporation of boric acid in the polymeric chain, by analogy to carboxylic acids, was ruled out. Retrospectively, it was fortuitous that this work was conducted with aerogels, and the model system utilized H3BO3, whereas the byproduct, B2O3, could be removed easily from the porous network leaving behind pure polyurea. With other mineral acids results could have been misleading, because the corresponding oxides are insoluble and remain within the polymer (via skeletal density determinations and EDS). On the positive side, the latter is a convenient method for in situ doping robust porous polymeric networks with oxide or pure metal nanoparticles (Au in the case of H3AuO3) for possible applications in catalysis.

 

Part B: Ferrocene-based Polyamide Aerogels: Graphitization, Transmetalation,

and Use in Heterogeneous Catalysis

     Ferrocene-polyamide aerogels (Fc-PA) incorporating one ferrocene moiety in every polymer repeat unit were prepared in one pot via an underutilized reaction between a triisocyanate and ferrocene dicarboxylic acid. Fc-PA aerogels have high porosities (up to 92% v/v of empty space) and surface areas (up to 456 m2g-1). Upon pyrolysis (800-1400 °C / H2), Fc-PA aerogels decompose to Fe(0) and carbon but remain monolithic. Fe(0) catalyzes low-temperature graphitization in its vicinity, thus the resulting materials consist of Fe(0) nanoparticles (20-25 nm in diameter, wrapped in graphitic ribbons (4-5 nm thick), and the whole assemblies are embedded in the nanoporous matrix of amorphous/graphitic carbon (C-) aerogels. Such monolithic Fe(0)-doped C-aerogels (Fe@C) were transmetalated (tm-) quantitatively with several noble metals without sacrificing the intricate C-aerogel nanostructure. Surface areas and porosities of transmetalated C-aerogels (tm-M@C, M: Au, Pt, Pd) remain high (about 100 m2g-1 and 90% v/v, respectively), and their open structure facilitates rapid diffusion of reactants to the metal particles, rendering those materials particularly attractive as heterogeneous catalysts. The latter was demonstrated with reduction of nitrobenzene (Fe@C), oxidation of alcohols (tm-Pt@Cand tm-Pt@C) and Heck couplings (tm-Pd@C). Conversions were consistently high (80-100%), and at the end of each reaction the monolithic tm-M@C catalyst was harvested and reused several times without noticeable loss of activity.

 

2016

Tomorrow's Innovators and Instigators: Mars Rover Design Team

Alyssa McCarthy: Chief Executive Officer, Katelyn Brinker: Chief Technology Officer, Caroline Dziak: Science Team Leader, MS&T

Abstract: The Mars Rover Design Team designs and builds next generation rovers that will one day work alongside astronauts in the field. The team operates under the vision statement “Today. Tomorrow. Forever” and the technical branch of the team is divided into four sub-teams: Mechanical, Power, Telemetry and Controls, and Science. The science team focuses on developing systems and experiments to identify habitability. They are currently working on refining their custom Raman spectrometer and are developing a sample bay that will allow for collection of up to six samples. Furthermore, they are creating experiments to test for nitrates, salts, carbonates, and barium sulfate. Details about the rover, the team, the competition, and the science will be discussed.

The Microwave Spectrum and Large-Amplitude Motions of Pinacolone

Jon T. Hougen, Sensor Science Division, National Institure of Standards and Technology, Gaithersburg, MD

Abstract: The research for this talk consists entirely of microwave spectroscopic measurements and quantum mechanical calculations that are quite similar to the work in one group at the Department of Chemistry of Missouri University of Science and Technology.  Nevertheless, because the audience will presumably consist of many different kinds of chemists, I hope to spend about half of the talk mentioning various chemical considerations associated with pinacolone (even though that will take me far outside my area of expertise).

     Peripheral topics for the first 20 minutes of the talk at the “Wikipedia level” are:

  1. Volatile esters, aldehydes, and ketones as odorant molecules in the perfume and food industries. 
  2. The high sensitivity and specificity of the mammalian nose as a sensor of odors.
  3. Volatile compounds as pheromones for plants and animals.

Is there any hope that the precise molecular structures obtained from microwave spectroscopy will be of use in elucidating the mechanism(s) of smell at the molecular biology level?

     In the second 20 minutes of the talk pinacolone (methyl tert-butyl ketone, CH3-C(=O)-C-(CH3)3) will be used as the basis for a (hopefully) pedagogical discussion of some basic ideas concerning:

  1. The microwave instrumentation and supersonic cooling.
  2. Chemically interesting intramolecular motions where the atoms move by more than one bond length = large-amplitude motions.
  3. Electronic, vibrational, and rotational degrees of freedom in molecular spectra.
  4. The main quantum mechanical ideas used in this research (time-independent stationary states = boundary value problems), which are different from the main quantum mechanical ideas used to study chemical reactions (reactants change with time into products = initial value problems). 

     In addition, I will try to give a (light-hearted) overview of present-day scientific competition in the various laboratories around the world in this field. 

Coherent Control of Wave Transport in Scattering Media: Looking Through Walls and Aroung Corners

Alexey Yamilov, Dept. of Physics, MS&T

Abstract: The concept of diffusion is widely used to study the propagation of light through multiple scattering media such as clouds, interstellar gas, colloidal solutions, paint, and biological tissues. Diffusion, however, is an approximation as it neglects wave interference effects. Most of the scattered waves follow independent paths and have uncorrelated phases, so their interference is averaged out. Notwithstanding, a wave may return to a position it has previously visited after multiple scattering events, and there always exists the time-reversed path, which yields identical phase delay. Contributions due to constructive interference between these pairs of paths to transport coefficients, in particular second order quantities such as fluctuations and correlations, do not average out to zero.

     In this talk, I will review recent progress in coherent control waves in turbid media and describe a novel scheme of changing spatial structure of eigenchannels in the medium. It allows one to control the crossing probability of scattering paths as a function of position. I will illustrate this approach with several experiments demonstrating how the spatial dependence of the average intensity as well as the long-range correlations can be deterministically modified.

     In addition to fundamental importance, understanding and manipulating the spatial correlations of light inside the random system is useful for imaging and focusing of light in multiply scattering media using wave-front shaping techniques. The number and the spatial structure of the eigenchannels limit the degree of coherent control. Our results suggest that the sample geometry can provide an additional degree of freedom, which can be used alongside with wavefront shaping to control not only the transmitted and reflected light, but also the depth profile of energy density inside the scattering system.

Laser-induced Scalable Synthesis of Nanomaterials for Energy Storage and Conversion

Jian Lin, Dept. of Mechanical and Aerospace Engineering, MS&T

Abstract: Nanomaterials offer new opportunities for delivering efficient energy storage and conversion devices in people’s life due to their unique physical and chemical properties. Production of these nanomaterials in a scalable and cost-effective manner is essential for achieving this goal. In this talk, I will discuss how to produce and engineer carbon-based nanomaterials by a recently developed laser-induced method to manipulate electrons and ions at the nanoscale, which enables us to create efficient energy storage and conversion devices. This talk is composed of two parts: 1) laser induced synthesis of porous graphene-like nanomaterials by experimental and molecular dynamic simulation. Discuss their applications in in-plane microscale energy storage devices for microelectronics; 2) experimentally demonstrate laser synthesis and patterning of nanocatalysts for the application in hydrogen evolution reactions.

Unlocking the Mysteries of a Medieval Chant Book with Multispectral Imaging

Nathan A. Oyler: Dept. of Chem., Virginia Boston: Dept. of English, UMKC

Abstract: CODICES is a collaborative working group of faculty, students, and librarians who are focused on the analysis of manuscripts, texts, and early printed books with optical and computational techniques. We draw collaborators from many disciplines including English, Computer Science, Chemistry, Art History, and History. We conduct our research in working groups that coalesce around specific research questions and analytical techniques. We hope to be an incubator for faculty research, a training ground for graduate students, and a venue for undergraduate research. Our investigations to date have focused in the following areas:

    Visible Imaging: We capture visible-light images of manuscripts and early printed books and present them online in order to bring them to a broad public audience.

    Multispectral Imaging: We image selected pages from these manuscripts and early printed books at various frequencies in the ultraviolet-visible-near-infrared spectrum to answer questions about the books’ production and reception history.

    Book Histories: We have extensive book histories of the objects that we are investigating, describing the physical characteristics and provenance of these works.

    Our long-range goal is to develop tutorials that teach others how to build and use their own version of our home-built multispectral scanning system. We aim to offer humanities centers, libraries, and archives the ability to conduct their own investigations with these techniques using readily available and affordable equipment. The result of our project will be an expansion of the number of scholars and librarians who are able to use multispectral visualization techniques to study books in their own collections.

    In our presentation for MS&T, we will focus on the multispectral optical techniques we are using to study the palimpsests in a handwritten codex known as the Adair Chant Book, which is a fifteenth-century book of chants that have been scraped and rewritten, and the watermarks found in an early printed book, Antoninus’ Summa theologica, which was printed by Anton Koberger in 1486/87. Our investigations of these books illustrates how optical techniques can be used to recover lost material, as well as to identify and categorize watermarks in the Koberger volume.

 

General laboratory Safety Training: Safety

Environmental Health and Safety, MS&T

Abstract: 

  • General Safety
    • Environmental Health and Safety Department
    • General Rules/Policies and Prudent Practices
    • Fire Safety
    • Emergency Response
    • Hazard Communication
    • Engineering/Administrative Controls, and Personal Protective Equipment
    • Injury / Incident Reporting
  • Hazardous Material Safety and Management
    • Chemical/Biological/Radiological Hazards
    • Compressed Gas Cylinders / Cryogenics
    • Physical Hazards
    • Chemtrack Inventory System

General laboratory Safety Training: Environmental Compliance

Environmental Health and Safety, MS&T

Abstract: 

  • Environmental Management System
    • ISO 14001
    • Corrective action
  • Hazardous Waste Management
    • Federal Regulations
    • Chemical Waste – proper storage and labeling
    • Chemical Waste – pick-up request
    • Biological Waste
    • Universal Waste
    • Spill Response

Applying Quantum Monte Carlo Methods to the Electronic Structure Problem

Andrew D. Powell, Dept. of Chem., MS&T

Abstract: This presentation will be an overview of our progress in using Quantum Monte Carlo methods to describe the electronic structure of small molecular systems.  Quantum Monte Carlo (QMC) is a computational technique that can be applied to the electronic Schrödinger equation for molecules. QMC methods such as Variational Monte Carlo (VMC) and Diffusion Monte Carlo (DMC) have demonstrated the capability of capturing large fractions of the correlation energy, thus suggesting their possible use for high-accuracy quantum chemistry calculations. QMC methods scale particularly well (near linearly) with respect to parallelization, making them an attractive consideration in anticipation of next-generation computing architectures which will involve massive parallelization with millions of cores. Due to the statistical nature of the approach, in contrast to standard quantum chemistry methods, uncertainties (error-bars) are associated with each calculated energy. Cost, feasibility, and accuracy in the context of practical applications will be assessed. 

Using Reaction Kinetics to Assess Chemistry of Prospective Importance to the Origin of Life

Paul Brancher, Dept. of Chem., St. Louis University

Abstract: The question of how the first living system developed on early Earth is history's greatest unsolved mystery, and its answer all but certainly hinges on chemistry. Determining how the mixture of abiotic chemicals present four billion years ago could have naturally assembled into an autoamplifying network of reactions is a challenge of extraordinary complexity, and it can be difficult to decide where to begin. When evaluating chemical reactions proposed as relevant to the origin of life on Earth, the universal importance of water to life necessitates the consideration of hydrolysis as a deleterious side reaction. This presentation summarizes measurements of the rates of thiol-thioester exchange and thioester hydrolysis to assess the feasibility of a Thioester World-a period in early evolution where thioesters may have filled an important role as a kinetically stable, high-energy species like ATP does today. We will also discuss our latest data measuring the influence of simple salts on the rates of coupling and hydrolysis of peptides.

 

 

Bonding and Dynamics in Skutterudites

Raphael P. Hermann, Oak Ridge National Laboratory

 

History of the Missouri School of Mines, University of Missouri-Rolla, and the Missouri University of Science and Technology

Larry Gragg, Dept. of History and Philosophy, MS&T

 

Persistent Organic Pollutants to Peptides: Thirty-Nine Years of Analytical Chemistry Teachinga dn Research Efforts in the University of Missouri- System

Shubhender Kapila, Dept. of Chem., MS&T

 

Improving Genome Representation and the Software for Detecting Pathogens by WHole-Genome Sequencing

Prof. Chung Wong, Center for Nanoscience Biochemistry & Biotechnology, Dept. of Chem. and Biochem., UMSL

 

Rapid Quantification of Trypsin Inhibitors in Food and Feed Formulation with Electrospray Mass Spectrometry 

Radheshyam Panta, Dept. of Chem., MS&T

Abstract: Trypsin is a serine peptidase involved in breakdown of larger poly-peptides and proteins into smaller peptides which can be readily absorbed and thus plays an essential role in nutrition. Proteins in seeds of certain species such as legumes are known to inactivate trypsin and hinder digestion of protein and adversely affect nutrition. Such proteins are called trypsin inhibitors (TIs) and minimize or inhibit trypsin catalyzed degradation of the substrate thereby limiting the availability of amino acids to the animal. As a result, determination of TI content of feed and food is important to assess nutritive value of foods and feeds.

     At present TI content is determined with the American Association of Cereal Chemists method 22-40.01. The method relies on measurement of p-nitroaniline through absorption of radiation at 410 nm. The absorption based method suffers issues of non-linearity unless carried out within specified limits. A rapid, accurate, and precise method for the quantification of trypsin inhibitor activity was evaluated. The method utilizes electrospray mass spectrometry (ESI-MS) monitoring of alpha hydroxyl acid capped di-lysines as the substrate. Hydrolysis yields unique residues that were readily quantified with ESI-MS. Accuracy and precision of the approach compares favorably with that of the standard test method.

 

Liposomal Drug Delivery to Erythrocystics

Elizabeth Bowles, Dept. of Chem., MS&T

Abstract: Previous studies have shown that the controlled release of adenosine triphosphate (ATP) from human erythrocytes is an important mechanism for the regulation of vascular caliber.  However, erythrocytes from patients with pulmonary arterial hypertension (PAH) fail to release ATP in response to the physiological stimuli of exposure to low oxygen tension or mechanical deformation of a magnitude these cells would encounter in the pulmonary circulation. This defect could be a significant contributor to the increased pulmonary vascular resistance (PVR) that is the cause of thepathological increase in vascular pressures in humans with PAH.

     One important approach to the treatment of PAH is theadministration of drugs to reduce PVR.  These drugs include prostacyclin or its analogs and phosphodiesterase 5 (PDE5) inhibitors that can be used alone or in combination.  Each medication may have serious unwanted side effects that are additive when the drugs are used in combination.

     In this presentation, an alternative drug delivery technique using drug-loaded liposomes will be investigated that may allow for increased drug efficacy and, possibly, reduced unwanted side effects. Liposomes can encapsulate drugs and deliver them directly to specific cells.  The research presented will describe the successful incorporation and delivery of a clinically-used PDE5 inhibitor, tadalafil, via liposomes, to human erythrocytes.  This approach is shown to increase ATP release when the erythrocytes are exposed to the prostacyclin analog, UT-15C.  These findings demonstrate the effectiveness of this technique and form the basis for future in vivo trials to improve drug delivery and patient quality of life. Liposomal delivery, currently underutilized clinically, could represent a new treatment paradigm for patients with circulation issues.

Electrodepostion of Thin Metal Films for Use as Photoanodes

Caleb M. Hull, Dept. of Chem., MS&T

 

Fall Semester 2022

Chemical Inventory Management: S&T Chemtrack System

Office Staff, Environmental Health and Safety, Missouri S&T

  • General Information
    • Introduce Environmental Health and Safety
    • Show online General Laboratory Safety Training system
  • Hazardous Material Safety and Management
    • Chemtrack System
    • Keeping an accurate chemical inventor

New Methods for C–N and C–C Bond Formation Based on Unique Reactivity in Iron Complexes

Dr. Jamie Neely, Professor, Dept. of Chem., St. Louis University, St. Louis

For more information, click here

Abstract: First row transition metals present opportunities for the discovery of novel catalytic transformations enabled by their distinct reactivity. Iron complexes are especially attractive as transition metal catalysts given that iron is generally nontoxic and is the most abundant d-block metal in the Earth’s crust. Research in the Neely focuses on the development of new C–N and C–C bond-forming methods based on reactivity that is specific to iron. We take advantage of insights from stoichiometric studies to probe reaction mechanisms and optimize catalytic conditions. We are currently using this approach to explore iron-catalyzed methods for alkyne carboamination and linear trimerization.

Click to view Dr. Neely's Seminar Flyer

 

Environmental Compliance: Hazardous Material and Chemical Waste Management

Office Staff, Environmental Health and Safety, Missouri S&T

  • Hazardous Waste Management
    • Federal Regulations
    • Chemical Waste – proper storage and labeling
    • Chemical Waste – pick-up request
    • Biological Waste
    • Universal Waste
    • Spill Response

Chirality Determination and Enhancement of Carvone Using Microwave Three-Wave Mixing Spectroscopy

Nicole Moon, Graduate Student, Chemistry, Missouri S&T

Abstract: Building off the previous works of Schnell, Patterson, and Pate, a microwave three-wave mixing (M3WM) spectrometer has recently been constructed and demonstrated at Missouri University of Science and Technology for the use in chirality determination. Unique to this spectrometer is the use of multiple arbitrary waveform generators synchronized to one another to simultaneously generate the orthogonal microwave pulses needed for M3WM. The first molecule studied with this instrument was carvone, whose traditional microwave spectrum is dominated by internal rotation splittings caused by two non-equivalent methyl rotors. In addition to demonstrating the spectrometer’s capabilities, this experiment marked the first time a M3WM experiment was completely operable in the 6-18 GHz frequency region of the electromagnetic spectrum. Since the success of this initial experiment, preliminary work has begun on enhancing the chiral signal via a process known as chiral coherent quantum control. Recently acquired data shows much promise in this methodology. Within this seminar, the design, construction, and demonstration of the M3WM instrument’s capabilities using the enantiomers of carvone will be discussed along with a brief venture into the reinvestigation into the pure rotational spectrum of R-carvone.

High-spin quasiparticles in solid states

Dr. Hyunsoo Kim, Professor, Physics, Missouri S&T

Abstract: Quasiparticles with total angular momentum greater than j=1/2 can emerge in a solid state with strong spin-orbit interaction. Whilethe existence of such high-spin quasiparticles has been known for decades, their implication has been largely overlooked. The possibility of superconductivity beyond spin-triplet in such solid states attracted
substantial attention. In this talk, I will talk about unconventional quantum oscillations and superfluid response in half-Heusler YPtBi which is a topological semimetal with j=3/2 quasiparticles. The angledependent quantum oscillation exhibits striking anisotropy, and the London penetration depth varies as almost temperature-linear, both of which are not easily expected in a compound with cubic symmetry. These anomalous behaviors can be explained within j=3/2 Fermi surface and high-spin superconductivity.

Click to view Dr. Kim's Seminar Flyer.

Epitaxial Electrodeposition of Wide Bandgap Cuprous Bromides

Bin Luo, Graduate Student, Chemistry, Missouri S&T

Abstract: Cuprous halides are an important class of wide bandgap p-type semiconductors used in opto-electronics. Cuprous bromide (CuBr) shows potential for short-wavelength devices due to a large exciton binding energy (108 meV) and near-ultraviolet bandgap (3.1 eV). However, the growth of high-quality epitaxial CuBr films by electrodeposition has remained a challenge. Here, we introduce a low-cost electrochemical procedure for producing epitaxial CuBr(111) on a Ag(111) substrate by a [111]-oriented silver bromide (AgBr) buffer layer. The AgBr buffer layer forms during the electrodeposition of the CuBr. The mismatch between CuBr(111) and AgBr(111) is -1.3%. CuBr(100) is also produced on a Ag(100) surface by a AgBr(100) buffer layer that is rotated in-plane 45° relative to the Ag(100) surface.

 

Epitaxial Single-Domain Metal-Organic Framework Cu-BTC(111) Films by Electrochemical Conversion from Cu2O(111)

Xiaoting Zhang, Graduate Student, Chemistry, Missouri S&T

Abstract: Metal-organic frameworks (MOFs) are an important class of highly porous materials with extensive chemical and structural merits. However, the fabrication of MOF thin films orientated along all crystallographic axes remains a challenge. Here, we achieved highly crystalline single-domain MOF thin films with out-of-plane {111} crystal family by electrochemical conversion from cuprous oxide. Copper(II)-benzene-1,3,5-tricarboxylate, Cu3(BTC)2 (referred to as Cu-BTC) is a well-known metal-organic open framework material with a cubic crystal system. Highly ordered Cu-BTC(111) continuous thin films were produced by electrochemical oxidation using electrodeposited epitaxial Cu2O(111) films as substrate/precursor. In addition, free-standing Cu-BTC(111) membranes were obtained by epitaxial lift-off following the electrochemical etching of the residual Cu2O underneath Cu-BTC.

 

Developing a Community-of-Scholars Atmosphere in General Chemistry Courses

Dr. Steven W. Keller, Professor, Chemistry, University of Missouri, Columbia

Abstract: General Chemistry is often perceived (maybe even correctly) as a ”weed-out” class, a pair of courses literally designed to derail student goals and aspirations. Even in the absence of malicious intent, the combination of mathematical exactness and conceptual abstractness makes these courses difficult. While in no way am I advocating for us to shy away from challenging material, we will talk about ways of giving students a greater sense of ownership and inclusion even in a large lecture course. Individually designed research projects, small group activities (both in lab and in lecture) and a cooperative (as opposed to competitive) grading scheme are some ways I’ve been attempting to change the culture of the class.

Click to view Dr. Keller Seminar Flyer

Chasing Tack in Polymer (Gels)

Dr. Thomas Schuman, Professor, Chemistry, Missouri S&T

Abstract: Polymer gels are utilized for many applications: fuel cell membranes, ion exchange resins, super absorbent baby diapers, and, in our research, conformance control of eroded or fractured petroleum wells. Polymer gels are insoluble, crosslinked structures that can reduce permeability of otherwise open flow passages and, by disallowing water from flowing through the lease-resistance path, increases oil production by making water floods push oil rather than merely flow through unobstructed paths. The ability to redirect water to push oil is known as conformance control. Gels are made in water solution as bulk gels, resulting in a huge mass of water-swollen, crosslinked polymer. The bulk gel is dried and particulated to specific size distribution to produce what is known as preformed particle gels (PPG). These are redispersed into water and pumped into petroleum wells. The particles swell and their swollen mass sticks in pore channels, which reduces flow of that channel. Our recent developments have resulted in 6 patent/patent applications associated with compositions of polymer gels for conformance control purposes. In particular, the gel designs cause the swollen particle to display tack such that the particles can reassemble from PPG back into a bulk gel structure. A self-healing, auto-adherent aspect better occludes water channels and improves conformance control and oil recovery efficiency/reducing water cut of recovered fluid. The issue we have been chasing with respect to polymer gels is what enables self-healing, i.e., tack, and how do we design gels of different composition to possess tack? Tack is a polymer property where the polymer material is sticky and polymer chains can entangle in a structural way to develop strength. Plasticization is where polymers are swollen and have mobility and can entangle but not in a structural way; no strength is developed. Our first successful gel utilized a zirconium salt additive that provided tack, reassembly, and a strong bulk-gel-like material. A newly funded project is developing high temperature (300°C) PPG for sealing of geothermal well leakage. I will describe some of our developmental and initial work into the science of tack in polymer gels.

Click to view Dr. Thomas Schuman Flyer

Catalyst Design: Transition Metal Mixed Anionic Chalcogenides in Electrocatalytic Water Splitting and CO2 Reduction Applications

Ibrahim Abdullahi, Graduate Student, Chemistry, Missouri S&T

Abstract: While there is increasing depletion of the world’s fossil fuels, CO2 emissions from fossil fuels is rapidly increasing worldwide, and strategies are direly needed to prevent further increase in atmospheric CO2 levels. Electrochemical water splitting to generate O2 and H2 as zero emission energy source along with direct conversion of CO2 into value-added chemicals are viable approaches proposed to address this issue. Transition metal chalcogenides have been recognized as one of the most promising class of compounds that showed huge potential for both water splitting and CO2 reduction reaction (CO2RR). Our work focuses on catalyst design, via systematic and exploratory approaches to understand inherent property of catalyst from its isolated core metal complexes with M-En central core (M = metal; E = S, Se, and Te), and how it compares with a bulk nanostructured solid with similar M-En bonding nature, and their effect towards OER and CO2RR. This gives a good understanding of the active site chemistry, predict activity and trends as well as leads to a fundamental knowledge about better catalyst choice for OER and CO2RR. Various systematically designed electrocatalytic systems: tetrahedral bis(diselenoimidodiphosphinato) cobalt [Co{(SePiPr2)2N}2] and decacarbonyltrichromium diselenide [(CO)10Se2Cr3)]2- complex, metal embedded graphitic carbon aerogel from polyacrylonitrile, ternary metal based mixed anionic (telluro)-selenide and ceria-based fluorites series will be discussed, their syntheses, characterizations, and electrochemical studies towards OER and CO2RR will be presented.

Vibronic coupling in N-methylpyrrole

Alexander Davies, Post-doctoral fellow, Chemistry, Missouri S&T

Addressing diffusion in the solid photo- and photoeletrocatalysts

Pravas Deria, Associate professor, School of Chemical & Biomolecular Science, Southern Illinois University-Carbondale

Metal-Free Photoredox Catalysis for the S-Trifluoromethylation of Heteroaromatic Thiols

Raheemat Rafiu, Graduate Student, Chemistry, Missouri S&T

Evaluation of N-acetylcysteine Amide as a Potential treatment option for Traumatic Brain Injury using tandem LC-MS

Olajide Adetunji, Graduate Student, Chemistry, Missouri S&T

Development of Catalytic Membranes and Composites for Energy Storage Devices and Nonenzymatic Biosensors

Harish Singh, Graduate Student, Chemistry, Missouri S&T

 Synthesis, Development and Applications of Novel Transition Metal Complexes

Meenakshi Sharma, Graduate Student, Chemistry, Missouri S&T

Accessing anionic and cationic redox in metal chalcogenides through building block approach

Santhoshkumar Sundaramoorthy, Graduate Student, Chemistry, Missouri S&T

Harnessing the chemistry of cementitious materials towards the next-generation eco-efficient concretes

Monday Okoronkwo, Assistant professor, Chemical and Biochemical Engineering, Missouri S&T

Exploring the Application of DNA Nanostructures in the Electrochemical Biosensors and Microbial Fuel Cells

Krishna Thapa, Graduate Student, Chemistry, Missouri S&T

Abstract: With the extraordinary biocompatibility and programmability to accurately organize nanoscale materials, DNA nanostructures have been extensively explored for various of applications, such as biosensing, imaging, drug delivery, and stimuli-responsive devices. In the past decades, DNA-based electrochemical biosensor has attracted broad scientific and clinical interests due to its unique hybridization specificity, fast response time, and potential for miniaturization. Here, a novel 3D DNA origami-based ultrasensitive electrochemical biosensor for detection of let-7i miRNA, a biomarker for Traumatic Brain Injury (TBI) will be presented. In addition, with its ability to self-assemble into diverse multidimensional structures, DNA origami nanostructure has shown great promise as a carrier for small organic molecules, such as chemotherapy drugs and fluorescent dyes. For the first time, a three-dimensional DNA origami nanostructure serving as electron mediator-methylene blue carriers was employed to enhance the electron production and transfer in E. Coli system-based Microbial Fuel Cells.

Introducing polybenzodiazine aerogels as all nitrogen analogs of polybenzoxazines; synthesis, characterization, and their application in CO2 capture

Vaibhav Edlabadkar, Graduate Student, Chemistry, Missouri S&T

Abstract: Tetrahydroquinazoline (THQ) was designed as an all-nitrogen analogue of main-stream benzoxazine monomers. THQ solutions in DMF gelled at 100 oC via HCl-catalyzed ring opening polymerization to polybenzodiazine (PBDAZ) wet gels, which were dried in an autoclave with supercritical fluid CO2 to nanoporous solids classified as aerogels. Such aerogels are referred to as PBDAZ-100 and undergo ring-fusion aromatization at 240 oC under O2 to PBDAZ-240. Chemical identification of PBDAZ-100 and PBDAZ-240 relied on consideration of all nine possible polymerization pathways, in combination with elemental analysis, infrared and solid-state 13C NMR spectroscopy, and 15N NMR spectroscopy of aerogels from selectively 15N-enriched THQ monomer. Subsequently, fully oxidized PBDAZ-240 aerogels were carbonized at 800 oC under Ar to carbon aerogels. The resulting C-PBDAZ-800 carbon aerogels were further etched chemically under flowing CO2 at 1000 oC. PBDAZ-derived carbons and etched carbons were evaluated for their CO2 adsorption capacity and selectivity towards other gases. CO2-etched carbon aerogels showed very high CO2 uptake (11.2 ± 0.9 mmol g−1 at 273 K, 1 bar). The high selectivity of CO2 versus H2 in the range of (407 ± 104) is attractive for pre-combustion capture of CO2 and the high selectivity of CO2 versus N2 in the range of (52 ± 18) is attractive for post-combustion CO2 capture from flue gases.

Development and Analysis of Ringdown-Free T1 Relaxation Methods

Zachary Mayes, Graduate Student, Chemistry, Missouri S&T

Abstract: Longitudinal nuclear-spin relaxation (T1 relaxation) has long been used to gain information about the immediate molecular vicinity of NMR-active nuclear spins. While the chemical shift offers information about the magnetic field at the location of an investigated nucleus and, thus, the electronic structure of a molecule, information gained from T1 relaxation relates to the mobility and vicinity of a molecule. The mobility of molecules is influenced by its rigidity, the temperature of the environment and, in case of porous media, by the pore size and molecule-surface interactions. Two new NMR relaxation techniques are introduced making it possible to accurately determine T1 times under specific conditions that would be considered unfavorable for NMR measurements. First, a pulse-ringdown-free Freeman-Hill-inspired experiment is presented, which is particularly useful when metal pressure probes are used for NMR investigations, such as the toroid cavity probe. Further developments of the ringdown-free T1 experiment are the RAPTOR (Rapid Acquisition Pulse Train to Observe Relaxation) method and its frequency-selective extension RAPTOR-S. Both RAPTOR sequences were developed to drastically reduce experimental time for T1 time determinations. The accuracy of the ringdown-free techniques including RAPTOR and RAPTOR-S are tested and compared with standard T1 methods.

Nitrene Transfer Chemistry Mediated via Transition Metal (M = Cu, Mn, Fe and Co) Coordination Reagents

Suraj Sahoo, Graduate Student, Chemistry, Missouri S&T

Abstract: A family of cationic divalent and monovalent metal complexes (M = Mn, Fe, Co, Cu) using tris[(tetramethylguanidino)phenyl]amine and corresponding bipodal congener (N-methyl-bis[(tetramethylguanidino)phenyl]amine) were synthesized. The tripodal complexes were obtained from the reaction of the corresponding ligand and [M(NCMe)6(PF6)2 precursors. Alternatively, the bipodal complexes were prepared via a two-step process, initially with the reaction between the ligands and metal chlorides (MnCl2, FeCl2 and CoCl2) followed by a substitution reaction with TlPF6 to afford bipodal metal complex analogues (with acetonitrile coordination) with the exception of copper, where in [Cu(NCMe)4][PF6]2 was used directly as the precursor. The characterization of this family of cationic complexes exhibited stoichiometric variations and structural complexities with the expected result that the bipodal analogues offered additional coordination sites for catalytic studies as compared to the tripodal complexes. An extensive comparative study was then carried out in terms of nitrene transfer chemistry towards aziridination of olefins with certain metal complexes showing additional activity towards formation of five membered heterocycles (pyrrolidines and imidazolines) in presence of excess olefins or acetonitrile. The catalytic reactions were then judiciously optimized with the most productive iron reagents, and mechanistic studies uncovered the dual role of the metal as a nitrene-transfer agent and a Lewis acid.

Development of Rapid and Sensitive Methods for Trace Analysis of Phytohormones and Lipid Peroxidation Products in Corn Seeds

Sargun Kaur, Graduate Student, Chemistry, Missouri S&T

Abstract: Plant seed germination, growth, and response to biotic and abiotic stresses are regulated by plant hormones (phytohormones). Various phytohormones have synergistic or antagonistic functions during the germination and growth stages. Stored seeds can deteriorate and become susceptible to various environmental stresses and diseases. Therefore, the measurement of phytohormone and other metabolite levels can provide an insight into seed germination, viability, and vigor. Simultaneous screening of different classes of phytohormones and lipid-peroxidation products was accomplished with a newly developed liquid chromatography – tandem mass spectrometry (LC-MS/MS) method using rapid non-derivatized sample preparation. The types and levels of volatile compounds emitted from seeds can also be a quantitative indicator of the seed germination potential and vigor. Low molecular weight volatile compounds such as short-chain aldehydes, alcohols and carboxylic acids may be used as chemical markers for assessing the seed quality since they are produced from the lipid peroxidation initiated by autooxidation or enzymatic oxidation of unsaturated fatty acids during the seed storage and aging period. Therefore, a headspace – solid-phase microextraction – gas chromatography/mass spectrometry (HS-SPME-GC/MS) method was developed and validated for analyzing these volatile organic compounds in corn (Zea mays) seeds.

Spring Semester 2022

Career Opportunities and Employer Relations: Student Services

Hannah Ramsey-Standage, Student Service Coordinator, COER, Missouri S&T

Description: Career Opportunities and Employer Relations (COER) is located on the 3rd floor of Norwood Hall. COER is dedicated to helping Missouri S&T students and alumni pursue their career goals assisting in all stages from summer internships, to co-ops and full-time employment. Services include student advising, LinkedIn reviews, professional development workshops, career fairs and more!

Designing complex chalcogenides using building block approach for energy storage and energy conversion applications

Srikanth Balijapelly, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: Solid-state chalcogenides have been the foundation of electronics industry and many emerging technologies such as batteries, thermoelectric, spintronics and non-linear optics. Therefore, new materials discovery with enhanced properties has been an attractive and modern area of research in the current decade. Chalcogenides are compounds of metal with sulfur, selenium, and tellurium. Semiconducting to metallic nature induced by lower electronegativity of S, Se, and Te makes this class of compounds scientifically interesting for diverse applications. However, a large class of complex chalcogenides are still undiscovered due to the lack of predictive tools in high temperature exploratory solid-state reactions. In this work, we present a new synthetic methodology called ‘Building Block Approach’ which takes advantage of the preformed main group molecular building units as reaction precursors with metal chloride salts. Employing this approach, a library of materials from layered to three-dimensional crystal structures have been discovered. The in situ synchrotron powder X-ray diffraction studies are employed to understand the reaction mechanism and product formation, which unveiled that product formation takes place within a second at a particular temperature through a solid-state diffusion. Magnetism, linear and nonlinear optical properties, ionic conductivity, and electrochemical properties of the synthesized materials will be presented.

Rapid synthesis of primary amines by radical C-H amination

Dr. Robert J. Comito, Dept. of Chem., University of Houston, Houston, TX

For more information, visit the webpage here. 

Abstract: Simple amination of sp3 C-H bonds to primary amines (RNH2) would rapidly accelerate the synthesis of bioactive alkaloids and the postsynthetic modification of polymers. Yet this transformation remains highly limited in comparison to simple hydroxylation and halogenation, reactions fundamental both to both biosynthesis and industrial organic chemistry. This talk discusses my laboratory’s development of an intermolecular sp3 C-H amination protocol that delivers primary ammonium salts (R-NH3Cl) in one pot upon aqueous workup. Mild conditions, good site selectivity, and reactivity on unactivated sp3 C-H bonds distinguish our method from other radical CH amination reactions. We have further characterized a unique mechanism involving hydrogen-atom transfer to iminyl radicals that will inform the development of CH activation chemistry. I discuss out ongoing application of this method to material synthesis and our strategies to control site selectivity by electronic tuning. 

About the Speaker: Robert Comito is a synthetic organic chemist who studies new reactions and catalysts for small molecule and polymer synthesis. Robert completed a BA in chemistry and mathematics at Rutgers University in New Jersey, the state where Robert grew up. While at Rutgers, Robert studied medicinal chemistry with Prof. Spencer Knapp and at the Merck Future Talent Program. Robert then completed his PhD in 2014 at Princeton University with future Nobel Prize winner David MacMillan. His thesis focused on asymmetric alkylation reactions using organocatalysis and the total synthesis of polypyrrolindoline natural products. Robert then pursued postdoctoral studies at Massachusetts Institute of Technology under Mircea Dinca, where he studied olefin upgrading and polymer synthesis with metal-organic frameworks. In 2018, Robert joined the faculty at the University of Houston as the Herman and Joan Suit Professor of Polymer Chemistry. His research is supported by the ACS Petroleum Research Fund and the Welch Foundation. Robert currently leads a team of 8 graduate students, one postdoc, and four undergraduates. Robert also serves on the UH Chemistry department's graduate admissions committee and is a good person to contact about graduate opportunities at UH.

The informational flyer can be downloaded here: Feb. 7 Flyer (Dr. Robert Comito)

Synthesis of Tetraaza and Tetraamido Macrocyclic Ligands and their Metal Complexes: Potential Catalysts in Nitrene Transfer Chemistry

Himanshu Bhatia, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: Atom/group-transfer chemistry along with direct and selective functionalization of C-H and C=C bonds has a great potential towards generating a plethora of high value chemical compounds. Our work seeks to produce and expand a library of catalysts used for carbon or nitrogen group insertion chemistry by utilizing earth-abundant transition metals. Macrocyclic ligand metal complexes have been targeted for their potential as catalysts, as they are thermodynamically more stable and oxidatively robust. Recent work has involved frameworks with the end goal of N4 coordination of the desired transition metals. Tetraaza macrocyclic chiral solvating agents (TAMCSA) have been synthesized and are currently being further explored as chelating agents of metal catalysts for nitrene- and carbene- transfer chemistry vis-à-vis C–H and C=C bonds. A series of tetraamido and tetraaza macrocyclic ligands have been synthesized and metallated with suitable Cu, Fe and Co precursors, and further employed for the aziridination of olefins and amination of C–H bonds.

 

Fiber-Optic Raman Sensor in Material Science and Biochemical Application

Bohong Zhang, Graduate Student, Electrical Engineering, Missouri S&T

Abtract: In the past few decades, Raman spectroscopy has had undergone growth as a great molecular analysis technique. When light interacts with molecules in the sample, most photons are dispersed or scattered at equal electricity as they are incident. However, a very small number of photons appeared at energy levels to form inelastic scattering, which is detected by the spectrometer as the Raman spectrum. Due to the different molecules constituting the material, the energy transferred by the scattered light through molecular vibration varies greatly. Then, Raman spectroscopy has been considered a fingerprint technique to identify and distinguish molecules in materials. Compared with the traditional Raman spectroscopy system, the fiber-optic Raman sensor has unique advantages such as small size, lightweight, low cost, and high precision. Fiber-optic Raman sensor has been found in various sensing and measurement applications. Based on the micro-material properties, the fiber-optic Raman probe is widely used in the research of material science and biomedical. In this seminar, several fiber-optic Raman probes such as the High-Temperature Raman probe, Miniaturized Raman probe, and surface-enhanced Raman probe will be introduced with different applications.

Computational Study of Rotation-Inversion Isomerization of N-Ethyl-N-(2,2,2-trifluoroethyl) Methyl Carbamate

Brian Jameson, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: While developing a synthetic route for fluoro-functionalized lysine derivatives, we observed the presence of two quartets in the 13C NMR spectra corresponding to the -CF3 group of amine containing intermediates with a tert-butyl carbamate (Boc) protecting group. The presence of the second set of peaks occurred only in Boc protected species, and we hypothesized that two isomers of the carbamate intermediates were present in solution. Based on extensive computational studies of the conformational space, we can confidently assign the two sets of -CF3 quartets to two rotational isomers (rotamers) about the N-CO2R carbamate bond. Here, we report the results of computational studies for the model system N-ethyl-N-(2,2,2-trifluoroethyl) methyl carbamate which explain the presence of two rotamers. The CN rotational profiles were investigated by coupled rotation-inversion mapping, indicating eight distinct transition state structures between four minima. The computed 13C NMR chemical shifts and 13C-19F J-coupling constants of the most stable rotamers are in good agreement with the experimental spectra.

                 

Figure 1. Rotation-inversion surfaces E(ρ,π) for E/Z-isomerizations E-1Z-2 via TS structures 3b.

 

Weyl semimetals: the case of CeAlGe

Dr. Halyna Hodovanets, Assistant Professor, Physics, Missouri S&T

Abstract: Single crystals have played an important role in technological advances. One notable example is silicon which is widely used nowadays in transistors, solar cells, semiconductor detectors, and most importantly integrated circuits (chips) used in the computer. Up until now, the scaled size, capacity, and speed of those chips have progressed immensely due to technological advances and have been roughly following Moore’s law. In order to achieve a further continued technology scaling of integrated circuits or replace them with new devices, new materials are necessary. New materials are especially important for the next generation of computers-quantum computers.

Weyl semimetals are among the materials proposed to have significant potential in informational technologies [1] and to harbor the necessary elements for quantum computing [2]. They host Weyl nodes at specific points in their Brillouin zone, a pair of relativistic fermions with different chirality, Weyl fermions. The nontrivial momentum-space topology due to the Weyl nodes leads to various fascinating phenomena, such as the chiral anomaly, chiral magnetic effect, anomalous magnetoresistance and Hall effect, [3,4] large nonsaturating thermopower [6] and ultrafast photocurrents [7] just to name a few. The essential ingredients for the realization of the Weyl semimetal are the absence of inversion symmetry and or time-reversal symmetry. The RAlX (where R = Rare Earth and X = Ge, Si) family has been recently identified as a large class of Weyl semimetal based on systematic first-principles band structure calculations.[8] In this respect, I will present details and importance of crystal growth of non-centrosymmetric CeAlGe single crystals, their physical properties, anomalous magnetotransport, and discuss the future implications of our findings and the tunability of RAlGe and RAlSi families.

[1] B. Zhao et al., Phys. Rev. Research 2, 013286 (2020).

[2] N. P. Armitage, E. J. Mele, and A. Vishwanath, Rev. Mod. Phys. 90, 015001 (2018).

[3] L. Wollmann, A. K. Nayak, S.S.P Parkin, and C. Felser, Book Series: Annual Review of Materials Research 47, 247 (2017).

[4] D. Li et al., Nature 572, 624 (2019).

[5] B. Skinner et al., Sci. Adv. 4, 1 (2019).

[6] N. Sirica et al., Phys. Rev. Lett. 122, 197401 (2019).

[7] G. Chang et al., Phys. Rev. B 97, 041104 (2018).

For more information, see the seminar flyer for Dr. Halyna Hodovanets

Epitaxial electrodeposition of transparent hole conductors and lift-off of ordered foils for flexible electronics

Bin Luo, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: Epitaxial electrodeposition is a simple, low-cost technology to produce highly ordered materials on single-crystal surfaces. Epitaxial lift-off of films can produce free-standing ordered foils for flexible electronics. In this talk, we will discuss the epitaxial electrodeposition of materials and lift-off flexible foils. Firstly, an epitaxial Cu(111) film was electrodeposited on a self-assembled monolayer (SAM) of the amino acid L-cysteine on Au(111). Direct epitaxial lift-off of the Cu film without etching gives a single-crystal-like Cu(111) foil which could be utilized as flexible substrate for further growing other ordered materials. Secondly, epitaxial hole conductor CuSCN nanorods were electrodeposited onto Au(111). Highly-ordered CuSCN could provide a low density of defect sites and grain boundaries, suppressing charge recombination probabilities and facilitating efficient charge transport in opto-electronic devices such as perovskite solar cells. An ordered and transparent CuSCN foil was produced by epitaxial lift-off following a triiodide etch of the thin Au substrate. In addition, preliminary results will be presented on the low-mismatch CuCl(111)//Si(111) epitaxial systems.

Publications:

1. Luo, B.; Banik, A.; Bohannan, E. W.; Switzer, J. A. Epitaxial Electrodeposition of Cu (111) onto an l-Cysteine Self-Assembled Monolayer on Au (111) and Epitaxial Lift-Off of Single-Crystal-like Cu Foils for Flexible Electronics. J. Phys. Chem. C 2020, 124, 21426-21434.

2. Banik, A.; Tubbesing, J. Z.; Luo, B.; Zhang, X.; Switzer, J. A. Epitaxial Electrodeposition of Optically Transparent Hole-Conducting CuI on n-Si (111). Chem. Mater. 2021, 33, 3220-3227.

3. Luo, B.; Banik, A.; Bohannan, E. W.; Switzer, J. A. Epitaxial Electrodeposition of Hole-Transport β-CuSCN Nanorods on Au(111) at the Wafer Scale and Lift-off to Produce Flexible and Transparent Foils. Chem. Mater. 2022, 34, 970-978.

Molecular Engineering and Three-Dimensional Mapping of Interfaces at the Nanoscale

Dr. Shan Zhou (faculty candidate), Department of Materials Science and Engineering. University of Illinois at Urbana-Champaign

Abstract: I will discuss my work and vision on the foundational role of nanomaterial interfaces to address pressing needs in applications related tomaterial cytotoxicity, chiral metamaterials, energy storage and biomedicines. The first part of the talk will focus on molecular engineering of nanoparticles, including a “uphill” ligand exchange strategy that enables a complete replacement of strongly-bound surface species with weakly-bound biocompatible ligands on gold nanoparticles to reduce their cytotoxicity, a
regioselective strategy to decorate macromolecules precisely on designated sites of gold nanoparticles for their promises in biomedicines and selfassemblies, and an unprecedented demonstration on largescale selfassembled chiral superlattices achieved by tuning interparticle interactions via surface modifications. In the second part of my talk, I will discuss my efforts to understand the interfacial structures at the underexplored nanoscale by direct imaging. I will describe our recent development of electrochemical-3D-atomic force microscopy, a new tool with a high spatial resolution (sub-10 pm) and unique capabilities of characterizing soft interfacial structures at a solid-liquid interface, and showcase its capability in molecular mapping to establish the structure-property relationship in energy storage. These new advancements in surface chemistry and interface science are paving the way for the rational development of nanomaterials sought in energy and biomedical research. 

Dr. Shan Zhou Seminar Flyer

Advanced Analytical Instrument Methods for Structure Determination

Dr. Li Li, Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center

Abstract: The advances of modern analytical instruments have greatly extended our detection limit and improved resolution for structure determination, not only for small molecules but also for big complexes of proteins. Mass spectrometry and cryo-electron spectroscopy are among the most powerful analytical tools for life science studies. In this talk, I will discuss three associated projects. 1. Development of a novel ionization method named Continuous Flow Desorption Ionization (CF_EDESI) for mass spectrometry. This ionization method improves on traditional electrospray ionization (ESI) by conserving protein tertiary structure, reducing signal from undesired lipid adducts, and affording direct coupling with normal phase chiral separation. 2. Development of covalent and non-covalent “shift reagents” for improved separation of mono- and disaccharides in ion mobility mass spectrometry. 3. Application of cryo-electron microscopy and other structure biology methods to determine the 3D structures of fibrils formed from acetylated protein Tau peptides. I will also briefly discuss mass spectrometry tools for identifying microorganisms (Shimadzu MALDI_iD plus or Bruker MALDI Biotyper), imaging tissues (Bruker
Tissuetyper), and identifying protein-protein interactions (crosslinking mass spectrometry).

Dr. Li Li Seminar Flyer

Enhanced Separation of Rare Earth Elements (REEs) using Novel Ionic Liquids

Dr. Lana Z. Alagha, Dept. of Mining and Nuclear Engineering, Missouri S&T

Abstract: Owing to their crucial importance, increasing demands, and monopolistic supply, the development of novel technologies for the recovery of critical metals is of considerable significance. Ionic liquids are currently applied as alternatives to conventional solvents and extractants that are used in the solvent extraction process, which plays a major role in the hydrometallurgical separation of critical metals, due to their higher selectivity and physiochemical flexibility. This research developed a new type of ammonium-based functionalized ionic liquids (FILs) for improved extraction and separation of rare earth elements (REEs). Both anions and cations of synthesized FILs are composed of only C, H, O, and N atoms, which are incinerable and therefore would help to reduce the amounts of solid wastes produced by the extraction process. The developed FILs shows high extraction efficiency, improved loading capacity, fast kinetics, and enhanced selectivity towards heavy REEs. Moreover, back-extraction studies revealed that the synthesized FILs can be recycled and effectively reused in the extraction process.

Dr. Alagha's Seminar Flyer

Novel Synthetic methods for the Trifluoromethylation of Aldehyde Derived Hydrazones

Puspa Aryal, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: 

Part 1: Cu-Catalyzed C(sp2–H)-Trifluoromethylation of Aldehyde Hydrazones with Langlois Reagent

The C(sp2)-H trifluoromethylation of hydrazones would give access to the a-trifluoromethylated hydrazones that can serve as intermediates in the synthesis of pharmaceutically interesting, fluorinated compounds. Here, we demonstrate the Cu-Catalyzed C(sp2)-H trifluoromethylation of the aldehyde hydrazones under environmentally benign conditions using the readily available and cost effective Langlois reagent (sodium trifluoromethanesulfinate). This reaction is broadly applicable to a series of aromatic aldehyde N-amino morpholine hydrazones to give the corresponding C(sp2)-trifluoromethyl hydrazones in moderate to high yields. The reaction generally tolerates a series of electron-releasing as well as electron-withdrawing substituents on the aromatic ring.

Part 2: Acetic Acid-Promoted Transition Metal-Free, Photo redox Catalyzed Trifluoromethylation of Aldehyde Hydrazones

Radical C(sp2)-H trifluoromethylation of aromatic aldehyde hydrazones is achieved in moderate to high yields under oxidative photo redox catalysis conditions, using inexpensive, bench-stable sodium trifluoromethanesulfinate (Langlois reagent), and Rose Bengal (RB) as the photocatalyst in the presence of acetic acid as the promoter. Acetic acid accelerates the rates of trifluoromethylation reactions and substantially eliminates the formation of the adventitious byproducts.

Metal Sulfides as Emerging Paradigm for the Sequestration of Toxic Heavy Metals and Radionuclides

Dr. Saiful M. Islam, Dept. of Chem., Jackson State University, Jackson, MS

For more information, visit the webpage here. 

Abstract: Efficient treatment of wastewater such as industrial and nuclear waste effluents is one of the major concerns for countries all over the world. The design of an efficient and cost-effective adsorbent of toxic ions is of great interest to the scientific community. Metal sulfide is a remarkable class of materials that can lay out highly ordered crystalline and disordered amorphous solids with diverse structural features. Among these, the crystalline materials with molecular anionic features or open frameworks three- and two-dimensional structures display a rich abundance of sulfide that are exposed on building units. Similar exposure of sulfides is also observed in the meso to microporous amorphous metal sulfides. An integrated feature of the building motifs, surface-exposed basic frameworks and the strong Lewis acid-base interactions of the soft polarizable Lewis basic sulfides and Lewis acidic metal ions synergistically display an exceptional efficiency, selectivity, sorption kinetics for soft or relatively soft metal ions. Here, this research talk will focus on the rational design and the synthesis of metal sulfides with targeted sorption properties, structural features, and their applications in the sequestrations of chemically soft heavy metal and radioactive ions, as well as toxic gaseous species.

Click to view Dr. Islam's Seminar Flyer

Fall Semester 2021

Hazardous Material and Chemical Waste Management

Office Staff, Environmental Health and Safety, Missouri S&T

Abstract: 

Hazardous Waste Management

  • Federal Regulations
  • Chemical Waste - proper storage and labeling
  • Chemical Waste - pick-up request
  • Biological Waste
  • Universal Waste
    • Spill Response

 

 

S&T Chemtrack System

Office Staff, Environmental Health and Safety, Missouri S&T

Abstract:

  • General Information
    • Introduce Environmental Health and Safety
    • Show online General Laboratory Safety Training system
  • Hazardous Material Safety and Management
    • Chemtrack System
    • Keeping an accurate chemical inventory

Explosives education and research opportunities at Missouri S&T

Dr. Kwame Awuah-Offei, Interim Director Mining Eng., Professor, Mining & Nuc. Eng., Missouri S&T

Abstract: Missouri S&T has a long history of education and research relating to explosives and energetic materials. Our explosives engineering MS and PhD programs are unique in the US and offer a variety of courses and research opportunities for students and faculty. The current research initiatives include traumatic brain injury, mine safety, structural response, and industrial and other applications of explosives. This presentation provides an overview of the educational and research opportunities available through the Explosives Engineering program. The presentation emphasizes the role chemistry can play in advancing S&T’s research and educational mission in energetic materials and explosives.

For more information, see the flyer here

Accessing Mitochondrial Targets for Therapeutic Gain in Major Diseases

Dr. Shanta Dhar, Biochem. and Molecular Bio., Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine

Abstract: Noncommunicable and infectious diseases need innovative ways for treatment and prevention. For example, tumor cells adapt to diverge survival strategies defying traditional cancer therapies and challenge us to pursue new mechanistic and multimodal approaches. Our community needs to be well-equipped to handle emerging and re-emerging pathogens through rapid intervention, prevention, and treatment. Similarly, atherosclerosis and other hypercholesterolemia-related conditions pose a unique threat. Addressing resistant cancers, viral diseases, and cardiovascular diseases in general population as well as in pregnant women comes with significant barriers to effective treatment. In this presentation, I will discuss some of our recent developments on platform nanotechnologies which can utilize intracellular targeting strategies, use of prodrugs, and selective biological membrane crossing abilities to bring therapeutic gain in major diseases such as resistant cancers, atherosclerosis, and viral diseases such as HIV.

View the informational flyer here

Chemical Education and Outreach beyond Broader Impacts

Dr. Nancy Ruzycki, Mat. Sci. and Eng., University of Florida

Abstract: Academics often engage in broader impact efforts related to their research work designed to excite K12 students about science, but these efforts rarely result in any academic benefit for the student or teachers in the immediate community. How can graduate students and academic faculty design broader impact activities which benefit students and teachers and help to build your profile for authentic broader impact?

Being able to align authentic broader impact to research goals requires development of a logic model and use of system thinking practices to ensure there are measurable outcomes for activities at the student and teacher level in addition to having meaningful alignment to research projects. This talk will showcase the landscape of K12 opportunities and how you can create a logic model which addresses and aligns activities and outcomes. These logic models are also appropriate for use in NSF proposals.

For more information, see the flyer here

Electron (De)Localization in f-Element Systems: From Fundamental Questions to QIS Design Principles

Dr. Henry S. La Pierre, Dept. of Chem., Georgia Institute of Technology

Abstract: The La Pierre group studies how collective magnetic, physical, and chemical properties arise from electron (de)localization phenomena in f-element systems. Our studies include the development of solid-state and solution methodologies for the synthesis of novel lanthanide and actinide (Th – Pu) materials and complexes. These synthetic efforts are paired with synchrotron and neutron spectroscopies and physical property studies to break down the challenge of understanding the electronic structure of f-element systems. Particularly in solid-state systems, the f-elements present unique valence electronic structures due the near degeneracies engendered in these systems and strong electron correlation. Our efforts to-date have focused on the synthesis and analysis of systems governed by one of three phenomena: magnetic super-exchange (i.e. exchange coupled systems), multi-configurational electronic structures (ground state degeneracy including hybridization with ligand/band states), and mixed-valence metal ions (i.e. mixed f/d occupancy and mixed-oxidation states). Understanding and controlling the manifestation of these phenomena in molecular systems is crucial for understanding the interplay of these phenomena underpinning topological insulators such as SmB6 and PuB6 and superconductors such as CeCoIn5 and PuCoGa5. In turn, the group has employed this expanded fundamental understanding of f-element electronic structure to construct components of quantum information technologies (e.g. qubits, single-molecule magnets).

See the flyer here

Designer Nanoparticles to Overcome Therapeutic Resistance in Cancer

Dr. Raghuraman Kannan, Dept. of Radiology and Dept. of Bioeng., University of Missouri-Columbia

Abstract: Lung cancer is the number one cause of cancer-related deaths in men and women, with an 8-10 month post-treatment median survival time. Non-Small Cell Lung Cancer (NSCLC) accounts for 80 % of lung cancers.  The treatment plan for NSCLC patients is determined based on the active mutations (EGFR, ALK/ROS, and KRAS) present in the tumor. For example, if the patient bears mutations in the EGFR region, the treatment plan involves tyrosine kinase inhibitors (TKI) such as Osimertinib or Erlotinib.  The initial treatment eliminates the tumor from the patient, but the cancer returns after 12-14 months.  But, this time, the TKIs fail to control the tumor growth, finding an alternative pathway to survive.  Our team elucidated the mechanism of drug resistance and identified the alternative biomarker pathway.  Based on the data, we developed an RNAi -nanoparticle, which can reduce the tumor's biomarkers (or protein) levels.  The reduction in protein levels reverses the drug resistance in cancer and sensitizes it to TKI. Furthermore, we demonstrated that this nanoparticle could control tumor growth in several animal studies.  In the talk, I will present the synthesis of the designer RNAi nanoparticle and results from cell and animal studies. 

For more information, see the flyer here

Strong-field spectroscopies with ultrafast laser pulses

Dr. Anh-Thu Le, Dept. of Physics, University of Connecticut

Abstract: Recent progress in laser technology has led to new coherent light sources that can be used to investigate ultrafast processes in matter. To take advantage of these new light sources, different experimental techniques have been developed to reveal the inner-workings of coupled electron-nuclear dynamics in molecules. Our group has developed theoretical and computational tools to understand and decode hidden information from the experimental measurements. In this talk, I will present our group’s recent progress in understanding ultrafast intense laser-matter interactions using some of the most promising techniques such as laser-induced electron diffraction, high-harmonic generation spectroscopy, and attosecond transient absorption spectroscopy. Throughout the talk, I will also address the challenges and opportunities for practical realization of molecular "movies" with atomic resolution in space and time that can provide new insights into fundamental chemical reactions.

O2 Complexes

Amanda J. Duerden, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: Fundamental knowledge about Van der Waals (VDW) complexes (provided by the acquisition and interpretation of laboratory data in conjunction with theoretical and computational results), provides critical information for our understanding of chemical compositions, interactions, and reactions within our atmosphere, and throughout the universe. Despite the relevance, and longstanding interest, complexes involving molecular oxygen are still shrouded in mystery due to the incredible difficulty in nearly every aspect of their study.  This talk centers around invoking a 3-fold intertwined approach blending improving experimental data acquisition, fitting, and potential energy surfaces to explore of a family of small molecule O2-complexes.  Resulting serendipitous discoveries will also be discussed.

Evaluation of N-Acetylcysteine Amide as a Therapeutic for Traumatic Brain Injury Using LC-MS/MS

Olajide Adetunji, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: Head insult through forceful contact or explosion are the major causes of traumatic brain injury (TBI). The long-term TBI effects may be the result of oxidative stress, which arises from increased reactive oxygen species after physical disruption of neurons and glial cells. Emphasis has been placed on diagnosis, but an effective treatment remains lacking for this disease. In our study, N-acetylcysteine amide (NACA), an antioxidant prodrug with good bioavailability was evaluated for preventive and therapeutic efficacy for TBI-related oxidative damage. To induce mild to severe TBI, Rats were exposed to open-field blasts designed to mimic real-life explosion effects. Rats were administered NACA at varying concentrations and times to optimize the dosing conditions for this study. At the treatment-period end, blood, urine, and brain tissue samples were collected from the test animals. Rigorous sample preparation was conducted prior to the liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis to determine the levels of potential TBI biomarkers. LC-MS/MS methods were developed in both positive and negative electrospray ionization modes which yielded excellent sensitivity, linearity, recovery, and reproducibility for the investigated analytes. Oxidative stress biomarkers such as reduced/oxidized glutathione, N-acetylaspartic acid, 5-hydroxyindoleacetic acid, 8-isoprostaglandin and 4-hydroxynonenal were measured to evaluate the antioxidant treatment efficacy.

Metal-Free Photoredox-Catalysis for the S Trifluoromethylation (S–CF3) of Thiols

 

Raheemat Rafiu, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: The S-Trifluoromethylation of Thiols provides access to pharmaceutically interesting compounds.  The current synthetic methods for this trifluoromethylation reaction involve the use of either expensive noble-metal-based organometallic catalysts and expensive or toxic reagents. We have demonstrated a convenient visible-light photoredox catalyzed S-trifluoromethylation of various thiols under metal-free conditions, using the cost-effective sodium trifluoromethanesulfinate (Langlois regent) as the trifluoromethylating agent and diacetyl as the photocatalyst.  This novel organocatalysis-based synthetic method provides a convenient and cost-effective alternative to the transition-metal-catalyzed photoredox reactions. 

Monitoring pteridine levels in a progressive breast cancer cell model using HPLC-MS/MS

Lindsey K. Rasmussen, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: Pteridines include folate-derived metabolites that have been associated with certain cancers in clinical studies. However, their biological significance in cancer metabolism remains poorly understood. The purpose of this study was to examine the effects of tumorigenicity on pteridine metabolism by studying a panel of 15 pteridine derivatives using a progressive, isogenic human breast cell line model with and without folic acid dosing. Non-tumorigenic MCF10A, pre-malignant MCF10AT, and tumorigenic MCF10CA1a cells were dosed with folic acid and cultured. Pteridines were then analyzed in both intracellular and extracellular contexts using an improved HPLC-MS/MS method. Folic acid dosing resulted in increased extracellular levels of several pteridines in a dose-dependent manner. Extracellular pterin and 6-hydroxylumazine further correlated with tumorigenicity upon folic acid dosing, providing in vitro evidence in support of their development as novel cancer biomarkers. The pathway and metabolism of these pteridine breast cancer biomarkers derived from folic acid were further investigated.  To the best of our knowledge, this study presents the first use of an isogenic cancer cell model to investigate the effects of tumorigenicity on pteridine metabolism. This unique methodology may be extended to other metabolites and diseases to better understand the role of metabolites in disease etiology and progression.

Morphology-dependent mechanical properties of shape memory poly(isocyanurate-urethane) (PIR-PUR) aerogels

A B M Shaheen ud Doulah, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: The catalytic activity of a large number of metal ions is compared with a well-known catalyst, dibutyltin dilaurate, in the formation of shape memory poly(isocyanurate-urethane) (PIR-PUR) aerogels.  In turn, the catalytic activity, and thereby the gelation time, was correlated with the nanomorphology and the mechanical properties of the resulting materials. Fourth-period salts from FeCl3 to GaClas well as InCland SnCl4 catalyze formation of PIR-PUR aerogels. 119Sn NMR, indicates complex formation of the metal ion with TEG followed by reaction with the isocyanate. The gelation rate was found to increase from Fe to Cu and decline from Cu to Ga. As the gelation time decreased, the morphology of PIR-PUR aerogels changed from bicontinuous to spheroidal. For equal gelation times, the skeletal structural features were similar, irrespective of catalyst. Aerogels with bicontinuous frameworks were stiffer than those with spheroidal frameworks, and those consisting of smaller spheres were stiffer than those with larger spheres. Next, through structural design at the macro (bulk) scale, the shape-memory response of the stiffer version of these PIR-PUR aerogels (e.g., those with bicontinuous nanomorphologies), was augmented with an auxetic effect manifested by a negative Poisson’s ratio of approximately −0.8 at 15% compressive strain.

Multinary Sulfides with Potential Applications in Infrared Nonlinear Optical Devices

Dr. Jennifer Aitken, Chem. and Biochem., Duquesne University, Pittsburgh, PA

Abstract: Currently the only way to access the mid-IR spectral region using all solid-state laser (SSL) technology is with the use of down-conversion processes, such as second harmonic generation (SHG), implementing nonlinear optical (NLO) crystals. Yet, the current commercially-available IR NLO crystals have several shortcomings, including multiphoton absorption effects and low laser-induced damage thresholds (LIDTs) that limit the wavelength range and power output of the devices. Several groups are searching for new IR NLO materials implementing different strategies with hopes to access noncentrosymmetric (NCS) materials, because the lack of an inversion center is the first criterion for an SHG crystal. Our group has chosen to pursue the family of quaternary diamond-like semiconductors because their compositions are predictable based on valence electron rules and their structures are inherently noncentrosymmetric. Recently, we have identified several outstanding quaternary diamond-like semiconductor chalcogenides with strong SHG, impressive LIDTs and phase-matchability over a wide region. This seminar will discuss those results and outline future steps to elevate these materials to next-generation candidacy. 

For more information, see the flyer here

Quantitation of Urinary and Serum Metabolites for Clinical Assessment of Traumatic Brain Injury

Austin Sigler, Graduate Student, Dept. of Chem., Missouri S&T

Abstract: Traumatic brain injuries (TBI) induce complex neurometabolic changes rich with potential molecular biomarkers for injury characterization and severity assessment. Moreover, repetitive exposure to low-level blasts can produce progressive clinical and biological manifestations similar to mild TBIs. The detection of such subclinical injuries represents an unmet medical need. In response, an analytical workflow, consisting of four high-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS) methods, was developed to screen a panel of 22 metabolites putatively associated with TBI in serum and urine. In this study, a longitudinal study was conducted at the Urban Mobility Breacher Course at Fort Leonard Wood in which urinary and serum metabolites from 27 military personnel were compared before and during breacher training. The Wilcoxon Signed Rank test was used to find significant differences between the pre-blast and post-blast samples. Significant differences were observed allowing rejection of the null hypothesis and confirming the utility of several molecular biomarkers in the study. Additional statistical analysis was also performed and will be presented in detail. This project was supported by the Leonard Wood Institute through a Cooperative Agreement with the United States Army Research Laboratory (W911NF-14-2-0034).

Spring Semester 2021

Intellectual Property, Here and Elsewhere

John Woodson, Interim Director, Technology Transfer & Economic Development, Missouri S&T

Abstract: For over 150 years now, advancing science and scientific discovery been a cornerstone of education at Missouri University of Science & Technology. In fact, the University of Missouri System’s mission states that we are to “achieve excellence in the discovery, dissemination, preservation and application of knowledge”. The Technology Transfer & Economic Development Office plays an important role at Missouri S&T in the preservation (through patents and copyrights), dissemination (through licensing), and application (through finding commercial partners) of the university’s scientific discoveries. Many of the tasks performed by the TTED Office could apply for any or our students or even help them choose a career path or employer. This talk will explore the different types of intellectual property and how they fit in at the University and elsewhere.

Multifunctional Dendrimers For Drug and Gene Delivery

Dr. Hu Yang, Dept. of Chemical and Biological Engineering, Missouri S&T

Abstract: With collaboration with researchers with expertise in pharmaceutics and medicine, Dr. Yang’s laboratory is conducting cutting-edge research to improve therapeutic index & drug properties, achieve controlled release, enable non-invasive alternative administration and improve patient compliance; and foster translational and convergence research and education. He has been actively developing novel polymers, polymer-drug coupling chemistries, and creative approaches and models to address various challenges facing drug delivery in medication management and therapy. His ongoing projects are focused on the development and translational applications of efficient drug and gene delivery systems and formulations for cancer, ocular and cardiovascular diseases as well as exploration of non-invasive routs of administration for chronic disease medication management such as diabetes. In this talk, he will present the latest work on the development and translational application of the advanced drug and gene delivery systems for improved therapy of cancer, glaucoma, and atherosclerosis.

Bioanalyte Sensing with ZnO Carbon Nanotube and Silicon Nanowire Electrocatalysts

Dr. Charles Chusuei, Dept. of Chem., Middle Tennessee State University, Murfreesboro, TN

Abstract: The morphology and size of ZnO nanostructures were controlled using hydrothermal synthesis, varying the hydrothermal treatment temperature, before attachment to COOH-functionalized multi-​walled carbon nanotubes. High activity for H2O2 reduction was achieved when nanocomposite precursors with a roughly semi-​spherical morphology (no needle-​like particles present) formed at 90°C. A 2.4-​fold increase in cyclic voltammetry (CV) current accompanied by a decrease in overpotential from the composites made from the nanosized, needle-​like-​free ZnO shapes were shown compared to those produced from needle-​like ZnO structures. Electrocatalytic activity varied with pH, maximizing at pH 7.4. A stable, linear response for H2O2 in the 1-​20 mM range was observed.

Acetaminophen (APAP) is an antipyretic, analgesic agent, the overdose of which poses a risk for liver failure. An APAP sensor was made by depositing silicon nanowires (SiNWs) onto glassy carbon electrodes (GCEs). The electrocatalytic activity of the SiNW​/GCE sensors was monitored under varying pH and concentrations using CV and chronoamperometry (CA). CVs using SiNWs at 0.5-13 mM APAP was used to detect the redox potentials of APAP. The selective detection of APAP was then demonstrated using CA at +0.568 V vs Ag​/AgCl, where APAP is fully oxidized. SiNWs have promising use for APAP toxicity monitoring.

Unprecedented Response Times in Photorefractive Composites

Dr. Jeff Winiarz, Dept. of Chem., Missouri S&T 

Abstract: The photorefractive effect involves the creation of a reversible hologram generated through the intersection of two coherent beams in an appropriate medium and can be realized in polymeric composites which simultaneously exhibit photoconductive and electro-optic properties. Especially promising in this field are nanocomposites of polymers and inorganic semiconductor nanocrystals, commonly known as quantum dots. Initial experiments focused on the use of Q-dots as photosensitizers and the ability to easily control the magnitude of the bandgap through quantum confinement. The broad tunability of the spectral response and increased photo-charge generation efficiency were particularly attractive. More recently, however, time-of-flight experiments have revealed that the inclusion of Q-dots significantly enhances the mobility of charge carriers in polymeric composites. This enhanced mobility translates into an improved response time; an issue which has plagued this class of materials since their inception and has precluded their use in many practical applications. This seminar will present data confirming that through judicious selection of an appropriate semiconductor material, an enhanced charge-carrier mobility attributable to the nanocrystals can be realized, leading to improved response times.

A facile method to enable phosphoinositides cell-permeable and photoactivatable

Dr. Manish Singh, Dept. of Chem., Lincoln University, Jefferson City, MO

Abstract: Phosphoinositides (PIPs) are a diverse class of lipid signaling molecules implicated in nearly all facets of cell signaling including migration, proliferation, and apoptosis. Mutations in numerous PIP modifying enzymes occur frequently in human disease, especially cancers, though the effects of these mutations on the global metabolic system have been poorly defined. Likewise, heterogeneous protein expression and undefined feedback loops further complicate obtaining a global view of metabolism and understanding the PIP metabolic pathway’s role in disease. Current approaches have been unsuccessful in obtaining a systems-wide analysis due to various technical challenges including low sensitivity, use of indirect measurements of activity, and a lack of validated reporters and delivery methods. To achieve our goal of systematic analysis of PIPs cellular metabolism, we developed a simple photocaging technique for cellular delivery of fluorescent PIPs. This general photocaging method can be used to generate a variety of photolabile probes in a short span of time.  

Nanoscale imaging of electrochemical energy conversion and storage systems

Dr. Justin Sambar, Dept. of Chem., Colorado State University, Fort Collins, CO

Abstract: Nanostructured materials are poised to play an important role in clean and renewable energy. However, nanomaterials are chemically and structurally heterogeneous in size, shape, and surface structural features. We strive to understand the correlation between nanoparticle chemistry/structure and functional properties. The first part of my talk will focus on elucidating charge storage mechanisms in nanoscale materials related to electrochemical technologies such as batteries and smart windows. I will discuss our high-throughput electro-optical imaging method that measures the battery-like and capacitive-like (i.e., pseudocapacitive) charge storage contributions in single metal oxide nanoparticles. I will present our recent single particle-level measurements that show (1) individual particles exhibit different charge storage mechanisms at the same applied potential and (2) particle size-dependent pseudocapacitive charge storage properties. The second part of my talk will focus on solar energy conversion using ultrathin semiconductors such as monolayer-thick (ML) two-dimensional (2D) materials such as MoS2 and WS2. We developed a correlated laser reflection and scanning photocurrent microscopy approach to study how layer thickness and surface structural features (edges versus basal planes) influence solar energy conversion efficiency. I will highlight our photocurrent microscopy study that revealed how layer stacking order in heterojunction photoelectrodes influences charge separation, transport, and recombination pathways.

For more information, view the flyer here

Mixed Anionic Transition Metal Chalcogenides for High-efficiency Electrocatalytic Water Splitting

Ibrahim Abdullahi, Dept. of Chem., Missouri S&T

Abstract: Many transition metal chalcogenides-based materials have been reported for water splitting as OER, HER and bifunctional electrocatalyst. It is understood that decreasing the electronegativity of chalcogens in transition metal chalcogenide, increases covalency in the transition metal-chalcogen bond, altering the electronic band structure of the material and subsequently lowering the oxidation potential. However, the stability of the catalyst is compromised. Also, doping at transition metal sites have also been suggested to redistribute charge density around catalytically active sites therefore affecting their catalytic properties.

To provide more insight into the chemistry of these materials, from synthesis to structure-property relationship, the effect of mixed anion chalcogenides was investigated, by gradually replacing some portion of the chalcogen in transition metal chalcogenides with a different chalcogen. Here we present, a cobalt telluroselenide (Cox-Tey-Sez) series and their OER catalytic activity and stability.

Their electrochemical properties were investigated and compared to binary cobalt selenide and telluride. It was observed that the catalytic activity of the telluroselenides were higher than the selenide but lower than the telluride confirming that increasing anion electronegativity decreased catalytic activity. A systematic study of the chemistry of these new materials, their detailed characterization and OER catalytic efficiencies will discussed.

Activating Anionic Redox in Chalcogenides Materials for Battery Application

Santhosh Sundaramoorthy, Dept. of Chem., Missouri S&T

Abstract: Conventional Li-ion battery cathode’s charge storage mechanism solely depends on the transition metal redox. In the recent years Li-rich oxides are being explored owing to their high energy density compared to the existing cathodes due to the occurrence of cumulative cationic (M3+/4+, M = 3d, 4d transition metals) and anionic (O2-/O22-) redox mechanism. Yet these materials suffer from severe voltage fade, poor kinetics, and irreversible oxygen loss, which hinder its commercialization. One alternate approach to access reversible anionic redox is to replace the oxides by less electronegative sulfides, well known for their reversible dimer formation (S2-/S22-). In this work we have synthesized a host structure (Li1.33Sn0.67S2) which is electrochemically inactive due to its 3d10 (Sn4+) configuration though it has high theoretical capacity (233mAh/g). In order to trigger both the cationic and anionic redox we doped electrochemically active Fe2+ in Sn4+ site and formed a series of compounds (Li1.33-2y/3Sn0.67-y/3FeyS2; y = 0.1-0.5). Among those, y = 0.2 material showed excellent capacity of 130 mAh/g due to the cumulative Fe2+/3+ and S2-/S22- redox reactions. The material also showed no voltage fade and excellent cycle stability. Designing these type of sulfide cathodes opens up the gate for much safer and low-cost cathode materials.

Adventures in Chemical Metallurgy

Dr. Michael Moats, Dept. of Mat. Sci. & Eng., Missouri S&T

Abstract: The forthcoming energy transition has brought non-ferrous extractive metallurgy to the public conscience.  The robust supply of critical elements for green energy and the electrification of mobility is a global concern.  Mining and production of many critical metals are concentrated in a few countries. This has prompted governments to examine their domestic supply chains and discuss the possibility of onshoring production of certain elements.  During this seminar, Professor Moats will explore his career from Rolla undergraduate to corporate research manager to professor.  He will introduce the audience to various chemical metal production methods while interweaving past examples of research and technology development along with highlights from current and future research.

CO2 Utilization Via Carbonate-Promoted C–H Carboxylation and CO2 Hydrogenation

Dr. Aanindeeta Banerjee, Dept. of Chem., Stanford University, Palo Alto, CA

Abstract: With CO2 level in the atmosphere rising, finding new efficient ways to recycle this gas is of paramount importance. Though previous efforts have focused on converting CO2 to C1 compounds, the synthesis of multi-carbon compounds is advantageous because these targets have higher value and energy density. The key chemical challenge is forming C–C bonds without using energy-intensive reagents. I will describe a novel carboxylation reaction in which a C–H bond and CO2 are transformed into a carboxylate (C–CO2–) using alkali carbonates as a promoter, in absence of any catalyst or solvent. Alkali carbonate salts are capable of deprotonating C–H bonds that are ordinarily very weak acids (pKa>40 in organic solvent) to generate carbanions (C–) at intermediate temperatures (200-360 °C). In the presence of CO2, the carbanions react rapidly to form carboxylates. The chemistry has been applied in the synthesis of 2,5-furandicarboxylic acid (FDCA), an attractive green replacement for fossil fuel-derived terephthalic acid, used in polyethylene terephthalate (PET) polymer synthesis. Based on the above-described approach of C–C bond formation, I will also speak about how a mixture of alkali carbonate, CO2 and H2 can be readily converted to formate, oxalate and other C2+ carboxylates.

For more information, view the flyer here

Carbon aerogels derived from poly(tetrahydroquinazoline) for high capacity and selective adsorption of carbon dioxide

Vaibhav Edlabadkar, Dept. of Chem., Missouri S&T

Abstract: DMF solutions of a tetrahydroquinazoline (THQ) monomer were gelled via HCl-catalyzed ring opening polymerization at 100 °C. Poly(tetrahydroquinazolines) (PTHQ) wet gels were dried with supercritical fluid CO2 in an autoclave to aerogels, which undergo complete ring-fusion aromatization at 240 °C/O2. Based on selectively 15N-enriched materials in combination with solid-state CPMAS 13C and 15N NMR, it was found that the skeletal framework of fully-oxidized PTHQ aerogels includes amide, imide and urea groups. Fully oxidized PTHQ aerogels were carbonized at 800 °C/Ar and etched at 1000 °C/CO2 yielding carbon and etched carbon aerogels respectively. PTHQ-derived carbons were evaluated for their CO2 adsorption capacity and selectivity towards other gases.

CO2-etched carbon aerogels showed very high CO2 uptake (11.2 ± 0.9 mmol g−1 at 273 K, 1 bar), which was attributed to pore filling beyond monolayer coverage starting with preferential interaction of CO2 with surface pyridinic and pyridonic N on carbon (identified by XPS) in a near energy-neutral reaction. The high selectivity of CO2 versus H2 in the range of (407 ± 104) is attractive for pre-combustion capture of CO2 and the high selectivity of CO2 versus N2 in the range of (52 ± 18) is attractive for post-combustion CO2 capture from flue gases.

Chalcogenides as sodium ion conductors for solidstate batteries

Srikanth Balijapelly, Dept. of Chem., Missouri S&T

Abstract: A lithium-ion battery is composed of cathode, anode, separator, and electrolyte. Commercial lithium ion batteries use liquid electrolyte solution. On the other hand, a solid-state battery would use a solid electrolyte. The current Li-ion batteries suffer from safety issues due to the presence of flammable liquid electrolyte solution. Solid-state batteries are, therefore, inherently safer. Solid electrolyte is a key component in solid state battery. Solid electrolytes are solid materials containing highly mobile alkali ions. Unfortunately, there are not many good solid electrolytes to enable solid state batteries. Solid electrolytes with high ionic conductivities >10–4 S/cm with good thermal stability and wide electrochemical window are necessary to enable all solid-state batteries for practical applications. Hence, our focus was directed towards synthesizing new chalcogenide-based materials employing building block approach. In this regard, a new family of compounds, Na3MGaQ4 (M = Fe, Zn; Q = S, Se), have been synthesized and their crystal structures were determined. These materials contain large channels filled with Na-ions that show high ionic conductivity. Vacancy formation energies for the Na-ions were calculated using Density Functional theory and their role in the ionic conductivity will be discussed.

Designing Chemical Sensor Materials

Dr. John Determan, Dept. of Chem., Western Illinois University 

Abstract: Research presented will show the use of nanoparticles to detect illicit drugs.  Throughout the world, drug related crimes and abuse are prevalent.  Traditionally, analyses of drug samples involve complex reactions and the use of complex instrumentation, such as GC-MS.  This causes analysis of drug samples to be difficult to be done on site or by anyone without specialized training.

Recent studies, such as those by Mao et al, Sci Total Envir. 688 (2019) 771-779, show the possibility of drug analyses, specifically for methamphetamines, being conducted with gold nanoparticles capped with DNA aptamers.  A DNA aptamer is a synthetic single stranded DNA molecule.  These aptamers are designed such that they interact only with target molecule and not any similar molecules.  For example, a meth-aptamer will interact with methamphetamines, but not with pseudoephedrine.  When the drug interacts with the aptamer capped particle, the particle structure is change and a visible color change is observed.  While gold particles have been shown to work well for these analyses, we seek to use more affordable and abundant materials, to allow these techniques to be widely available.  We explore the use of copper, silver and silicon oxide based nanoparticles for the detection of illicit drugs.

Gravitational waves: Astrophysics Final Frontier

Dr. Marco Cavaglia, Dept. of Physics, Missouri S&T

Abstract: In 1916 Albert Einstein demonstrated that space and time can be warped in the shape of a wave. One hundred years later, scientists from the Laser Interferometer Gravitational-wave Observatory (LIGO) Scientific Collaboration and the Virgo Collaboration announced the first observation of a "ripple of space-time" from two colliding black holes. This scientific achievement marked the beginning of a new way of exploring the "dark side" of our Universe. Less than two years later, LIGO and Virgo scientists detected gravitational waves from the collision of two neutron stars, an event rapidly followed by the observation of light in all regions of the electromagnetic spectrum by hundreds of telescopes around the world and space in what became the most observed cosmic event in the history of humankind. Nowadays, detections of gravitational waves from collisions of neutron stars and black holes have become routine. They provide a new way to map the cosmos, test gravity under extreme-gravity conditions, study the structure of stellar objects, and understand the origin of matter and the evolution of the Universe.

For more information, view the flyer here

Protein and Small Molecule Engineering towards an Orthogonal Epigenetic Landscape

Dr. Kabirul Islam, Dept. of Chem., University of Pittsburg

Abstract: Epigenetics is a set of nucleosome-dependent biochemical processes that regulate transcriptional potential of genome and allows cells to access genetic information. Cells employ a range of epigenetic mechanisms, most prominent being the chemical modifications of DNA and histones to alter gene expression. Elucidation of how chromatin-modifying proteins remodel diploid human genome with exquisite spatiotemporal control is fundamentally important towards the understanding of eukaryotic biology and disease. Since starting at the University of Pittsburgh in 2014, my group has built the foundation of a vibrant research program guided by this question. We employ a range of small molecules, peptides, proteins, nucleotides and their unnatural analogues towards functional elucidation of chromatin modifications in transcription and nuclear reprogramming. Our interdisciplinary research spans synthetic organic chemistry, protein and oligonucleotide engineering, mechanistic biochemistry, cell and structural biology, proteomics and transcriptomics.

For more information, view the flyer here

Syntheses of Functional Drug Delivery Systems and Activatable Prodrugs for Cancer Therapy

Dr. Santimukul Santra, Dept. of Chem., Pittsburg State University

Abstract: The design and syntheses of biocompatible materials are emerging fields of research. In particular, designer dendritic biopolymers are important for the targeted drug delivery and cancer therapy. When compared with linear counter-part, three-dimensional biodegradable nanostructures offer better solubility, aqueous stability and huge functionality to effectively target tumor, minimizing severe side-effects to the healthy cells. Our lab is focused on developing new biocompatible polymeric and polymer-based nanomedicines for the targeted delivery of theranostic agents to the specific tumor. In addition, new methods developed for the synthesis of novel activatable prodrugs for the effective treatment of cancer. The multi-step syntheses of biodegradable dendritic polymers are able to encapsulate therapeutic drugs, MR probes and prodrugs within their three-dimensional cavities during the formulation of nanomedicines. To evaluate the therapeutic efficacy of these customized nanomedicines, various in vitro and in vivo assays were performed. This presentation will highlight the important roles of organic synthesis, chemical biology and nanotechnology in the field of biochemical and biomedical applications, and our current efforts in partnering with industries to bring this technology to the clinic.

For more information, view the flyer here

Fall Semester 2020

Nanodiamonds and Carbon Nano-Onions Ceramic Composites and their Applications

Ibrahim Abdullahi, Dept. of Chem., MS&T

Abstract: Luminescent nanodiamonds are photostable non-blinking fluorescent biocompatible, non-toxic, functionalizable materials made from high-pressure high-temperature (HPHT) microcrystalline diamonds, and have found application in biomedical imaging, nanosensing, quantum computing etc. However, search for more efficient, cost and time effective as well as commercially scalable techniques that produce small, bright, clean and high-quality fluorescent nanodiamonds is still on going. A novel scalable fabrication technique based on explosive fragmentation was developed. The particle size and photoluminesence properties of the fluorescent nanodiamonds obtained will be discussed. While ceramics and glasses are at the cutting edge of advanced materials and provide solutions to global challenges in the environment, aerospace, energy, manufacturing etc. There is, in fact, a need for more sophisticated approach to enable quick, cheaper and superior research and development of new material compositions for future applications. Annealed nanodiamonds yield carbon nano-onions, which have unique electrical, mechanical and optical properties. In situ generated carbon nano-onion/silica glass composites with varying carbon nano-onion concentration produced via base catalyzed sol-gel chemistry were investigated. Homogeneous dispersion, atomic parking density, residual porosity and tightly bonded particles network within the silica glass matrix influence the properties of the resulting composites, and their mechanical, optical and conducting properties will also be discussed.

General Laboratory Safety Training: University Laboratory Safety – Working Safely

Environmental Health and Safety, MS&T

Abstract:

General Safety

  • Environmental Health and Safety Department
  • General Rules/Policies and Prudent Practices
  • Fire Safety
  • Emergency Response
  • Hazard Communication
  • Engineering/Administrative Controls, and Personal Protective Equipment
  • Injury / Incident Reporting

Hazardous Material Safety and Management

  • Chemical/Biological/Radiological Hazards
  • Compressed Gas Cylinders / Cryogenics
  • Physical Hazards
  • Chemtrack Inventory System

General Laboratory Safety Training: Hazardous Material and Chemical Waste Management

Environmental Health and Safety, MS&T

Abstract:

Environmental Management System

  • ISO 14001
  • Corrective action

Hazardous Waste Management

  • Federal Regulations
  • Chemical Waste – proper storage and labeling
  • Chemical Waste – pick-up request
  • Biological Waste
  • Universal Waste
  • Spill Response

 

Development of intelligent stimuli-responsive biomaterials and nanodevices

Shuo Yang, Dept. of Chem., MS&T

Abstract: Considerable interest has been devoted to the development of stimuli-responsive biomaterials that could adopt different conformations in response to specific environmental stimuli, leading to broad applications in the fabrication of smart biosystems. Functional nucleic acids (DNAzymes, i-motif, and DNA triplex) as a novel branch of stimuli-responsive biomaterials, have shown great potential in the assembly/disassembly of nanomaterials due to their dynamic behaviors in response to external stimuli. The reversible assembly of DNA origami nanostructures by two types of stimuli: metal ion and pH will be presented. The metal-ion stimulated assembly/disassembly of DNA origami dimers were achieved by using G-quadruplexes as dynamic bridges (reversible conformation change between G-quadruplex state and its single-strand state) induced by potassium ions (K+). To extend the capabilities of DNA origami, the stepwise assembly of DNA origami nanoclusters via pH stimulation was further studied. Structure association and dissociation were controlled through a series of consecutive pH-stimulated processes relying on the transition of DNA triplex to duplex in different pH conditions. These dynamic assembly strategies, in response to external stimuli, bring more structural complexity and intriguing functions to the resulting biosystems.

 

 

Electrocatalytic processes for CO2 reduction and biomass conversion

Apurv Saxena, Dept. of Chem., MS&T

Abstract: While increasing CO2 enrichment in atmosphere has raised global concerns, major focus for mitigating this problem has been directed towards sequestration of atmospheric CO2 and converting it into value-added chemicals through CO2 reduction reaction (CO2RR). Electrocatalytic CO2RR is typically done on base metal plates such as Cu. However, these catalysts predominantly produce toxic CO which needs to be processed further to derive high-value products. The lack of product selectivity has also inhibited widespread application of these CO2RR base metal catalysts. Recently we have discovered that Cu- and Ni-based selenides, on the other hand, are highly efficient electrocatalysts for CO2RR, offering high selectivity towards C2-products under ambient conditions and low energy expense. Interestingly we have observed that these catalysts convert CO2 to methanol, ethanol, formic, and/or acetic acid at low applied potential with high product yield and selectivity. In this talk we will describe catalyst design principles to achieve high selectivity towards carbon-rich reduction products by applying fundamental concepts of inorganic chemistry. Detailed electrochemical measurements were performed to estimate conversion efficiency while products were quantified through NMR and GC-TCD. DFT calculations provided further insight of intermediate adsorption energies on catalyst surfaces which could be correlated with product specificity of various catalysts.

Analytical Method Development for Biomedical and Environmental Applications

Mousumi Bose, Dept. of Chem., MS&T

Abstract: Polymers are widely used materials for variety of applications. In biomedical field, luminescence quenching based optical oxygen sensors encapsulated in polymeric substances are gaining attention as a superior technology for continuous monitoring of oxygen. A simple and low-cost fabrication technique was developed to produce sensor arrays capable of two-dimensional oxygen tension measurement. Sensors were printed on polyvinylidene chloride film using an oxygen-sensitive ink cocktail, prepared by immobilizing Pt(II) meso-tetra(pentafluorophenyl)porphine (PtTFPP) in monodispersed polystyrene microparticles. The sensor patch along with smart phone-based readout technique is being evaluated as a smart bandage for early detection of pressure ulcer.

The environmental concerns and limited petroleum supply demand for replacing petroleum-based polymers with renewable bio-based sources completely or partially while maintaining comparable properties. Therefore, a sustainable and green approach was adopted to synthesize soy polyol-based rigid polyurethane (PU) foams for structural and thermal insulation applications. The effect of different additives, i.e., catalyst, blowing agent, surfactants, and polyol functionalities on foam properties were investigated. The focus of this work was to investigate the different synthetic formulations and potential to be used in structural insulated panel (SIP) for energy-efficient and modular building construction.

Subterranean Rhizoremediation Blues: Putting Rhizosphere Microbes to Work

Dr. David J. Westenberg, Dept. of Biological Sciences, MS&T

Abstract: Phytoremediation is an inexpensive and effective approach to the removal of environmental contaminants.  One approach to expand the spectrum of contaminants removed through phytoremediation is the use of microorganisms that reside in the rhizosphere - rhizoremediation.  This approach is attractive because: 1) rhizosphere microorganisms are capable of a broader range of metabolic activities relative to their host plants; 2) rhizosphere microorganisms can be manipulated to further expand their metabolic capabilities; 3) rhizosphere microorganisms are adapted to life in the rhizosphere.  In combination with the appropriate host plant, it is possible to maintain the population of contaminant degrading microorganisms throughout the remediation process. This presentation will describe several rhizoremediation project in my lab in collaboration with colleagues across campus.  

Simultaneous Determination of Urinary Metabolites for the Non-invasive Assessment of Traumatic Brain Injury

Austin Sigler, Dept. of Chem., MS&T

Abstract: Traumatic brain injury (TBI) is a serious public health concern for which sensitive and objective diagnostic methods remain lacking. While advances in neuroimaging have improved diagnostic capabilities, the complementary use of molecular biomarkers can provide clinicians with additional insight into the nature and severity of TBI. Growing understanding of TBI as a neurochemical cascade of events beginning with the initial insult has generated significant interest in the development of analytical methods to quantify neurologically relevant biomarkers with which to assess the severity of TBI. In the Dr. Shi lab, our group has developed several liquid chromatography tandem mass spectrometry (LC-MS/MS) methods to quantify several of these interesting metabolites in various biological fluids including urine. Urine presents unique preparatory challenges in analytical analysis due to its complex matrix and lack of homeostatic control in its production. This presentation will cover a few of the developments our group has made in biomarker discovery, as well as future directions which we are currently exploring in TBI analysis.

Corn Seed Quality Chemical Marker Discovery

Sargun Kaur, Dept. of Chem., MS&T

Abstract: The types and levels of volatile compounds emitted from seeds can be a quantitative indicator of seed quality such as germination potential and vigor. Low molecular weight compounds like short-chain aldehydes, alcohols and carboxylic acids may be used as chemical markers for assessing the seed quality since they are produced by lipid peroxidation initiated by autooxidation or enzymatic oxidation of unsaturated fatty acids during the seed storage and aging period. Therefore, a headspace – solid-phase microextraction – gas chromatography/mass spectrometry (HS-SPME-GC/MS) method was developed and validated for analyzing these volatile organic compounds in corn (Zea mays) seeds. This method allowed the fast identification and quantification of 19 volatile organic compounds including ketones, alcohols, aldehydes, limonene, and acetic acid. The headspace sampling of volatile compounds emitted from corn seeds were conducted using Carboxen/PDMS SPME fiber and desorbed directly into a heated injector for subsequent GC separation. High sensitivity and selectivity were achieved with the MS operating in SIM mode. The new method will be evaluated for quick and reproducible analysis for the assessment of seed quality and deterioration.

Design of nanocomposites and nanostructures for Energy storage and conversion in Supercapacitors and fuel cells application

Harish Singh, Dept. of Chem., MS&T

Abstract: Electrochemical capacitors (ECs) or Supercapacitors (SCs) are considered to be most promising energy storage devices and have received great attention because of their excellent electrochemical performance with high output power, short discharging time and long-term cycle stability. In the current work, transition metal telluride/selenide-based nanostructure composites were studied for SCs applications and oxygen reduction reaction as well. A specific capacitance of 1826 F/g was achieved at a current density of 1 A/g for metal telluride electrode. In terms of onset potential, kinetic current density and four-electron selectivity, metal selenide catalyst shows the comparable performance to those of commercial Pt/C towards the ORR, as demonstrated by cyclic voltammetry (CV) and polarization measurements. In this presentation we will discuss the SCs and oxygen reduction performance of these telluride/selenide nanostructures as well as the effect of transition metal doping and carbon nanostructure additives, and explain how the chemistry of transition metal chalcogenides influences their electrochemical functionality and potential as future energy storage and conversion.

Complex Chalcogenides for Heat Recovery

Srikanth Balijapelly, Dept. of Chem., MS&T

Abstract: More than two third of the energy generated across the globe is wasted in the form of heat. So, in order to build a sustainable energy source, it is very important to capture the waste heat. Thermoelectric devices are capable of direct conversion of heat to power and vice versa. Thermoelectrics are now being used in variety applications like waste auto-mobile exhaust heat recovery, thermoelectric coolers and radio isotope thermoelectric generators for NASA space craft powering. Though several solid materials have been investigated for thermoelectric activity, soft lattice, complex compositions and complex electronic structure make complex chalcogenides very attractive for thermoelectric applications. Taking advantage of plethora of mineral compositions that exist in chalcogenide family, we have targeted some complex compositions using fundamental concepts of developing high efficiency thermoelectric materials. In this presentation, the synthesis of few natural complex chalcogenide mineral compositions, challenges in their crystal structure solution, optical, electrical and thermal properties will be discussed.

Synthesis, characterization, and chemistry of two-dimensional transition metal carbides and nitrides (MXenes)

Shuohan Huang, Dept. of Chem., MS&T

Abstract: MXenes represent a relatively new and quickly growing family of two-dimensional (2D) early transition-metal carbides and nitrides, which were first synthesized in 2011 from bulk layered crystalline MAX phases. Because of their 2D structure and many extraordinary physical properties, MXenes have raised a significant interest for various applications. However, it has been found that in some cases MXene flakes are not stable and can spontaneously degrade on a time scale from hours to days. While dissolved O2 has been deemed as the main factor for the instability of MXenes in aqueous solutions, we analyze the role of water as the primary reagent, and not only a solvent, in the processes of conversion of 2D titanium carbide MXenes into titania. Moreover, we demonstrate gas analysis as a powerful technique to gain further insights into chemical reactivity of MXenes. Gases produced during chemical transformations of MXenes in aqueous solutions have been collected and analyzed via gas chromatography (GC) and Raman spectroscopy. The degradation rates of the MXenes in water were further investigated depending on their monolayer thickness within the same chemical composition, as well as depending on chemical composition of the materials within the same monolayer thickness. 

 

Rapid Measurements of Aerosol Size Distribution and Hygroscopic Growth with a Fast Integrated Mobility Spectrometer (FIMS)

Dr. Yang Wang, Dept. of Civil, Arch. & Environ. Engr., MS&T

Abstract: Aerosol size distribution and hygroscopicity are among key parameters in determining the impact of atmospheric aerosols on global radiation and climate change. In situ submicron aerosol size distribution measurements commonly involve a scanning mobility particle sizer (SMPS). The SMPS scanning time is in the scale of minutes, which is often too slow to capture the variation of aerosol size distribution, such as for aerosols formed via nucleation processes or measurements onboard research aircraft. To solve this problem, a Fast Integrated Mobility Spectrometer (FIMS) based on image processing was developed for rapid measurements of aerosol size distributions from 10 to 600 nm. The parallel comparison between the FIMS and SMPS demonstrated excellent agreement when measuring aerosols with various size spectra, but by simultaneously measuring aerosols with different sizes, the FIMS provides aerosol size spectra nearly 100 times faster than the SMPS.

Recent deployment onboard research aircraft demonstrated that the FIMS is capable of measuring aerosol size distributions in 1s, thereby offering a great advantage in applications requiring high time resolution. Such a system reduced the time of measuring the hygroscopic properties of submicron aerosols (six sizes) to less than three minutes in total, with an error within 1%.

Click here to view the seminar flyer. 

 

Enhancing Learning by Assessing More than Content Knowledge

Dr. Renée S. Cole, Dept. of Chem, University of Iowa

Abstract: Skills such as communication, teamwork, critical thinking, and problem solving are frequently cited as intended learning outcomes for STEM degree programs. While these skills, sometimes referred to as workplace or process skills, are highly valued, they are rarely explicitly assessed in the classroom. Assessment serves two purposes: (1) it provides a measure of achievement, and (2) it facilitates learning. The types of assessment used by an instructor also telegraphs to students what is valued in a course. However, in many instances, the lack of alignment between instructional methods and assessment detracts from the added value of engaged student learning environments. This NSF IUSE project focuses on the development and implementation of rubrics that facilitate providing feedback to students and informing the instructor as to the effectiveness of their instructional strategies in supporting process skill development. Implementation of the rubrics provides a means to better align intended outcomes with instructional activities and supports adoption of evidence-based active learning strategies that foster skill development in addition to content knowledge.

 

Networking with Chemistry Faculty at 9:45-10:45 am via ZOOM.  Networking with Teacher Education and Certification Faculty at 10:45 am – 12 pm via ZOOM.

Adsorption studies in Colloidal Unimolecular polymers

Ashish Zore, Dept. of Chem, MS&T

Abstract: Colloidal Unimolecular polymer (CUPs) is a single chain polymer nanoparticle made by a process of self-folding or self-assembly of polymer chain to form a particle. They are 3-9 nm in size, zero VOC, spheroidal particles that are self-stabilized via electronic repulsion due to the presence of surface charges which can be anionic or cationic groups. Designing a CUPs particle to meet ones requirements is extremely easy due to the flexibility and variability it offers in terms of size, charge density (number of charges per unit area on the surface) as well as the type of hydrophobic and hydrophilic monomers. Since each polymer chain collapses into a single particles, the size can be easily controlled by manipulating the molecular weight of the polymer. It is necessary to define the limits/range of CUP formation using a suitable parameter that can be easily applied to all types and size of monomers. This will simplify the synthesis of these particles. Surface tension is an important property in coatings and can be altered by the addition of CUP particles. CUP particles reduces the surface tension of the water and is now understood with help evaporation rate study. 

 

 

Development of high temperature resistant gels using low toxic polymers for conformance control

Buddhabhushan P. Salunkhe, Dept. of Chem, MS&T

Abstract: Preformed particle gels (PPGs), a type of hydrogel, are used in oilfield conformance control owing to their robust gel chemistries. Traditional PPGs are polyacrylamide based hydrogel compositions which can withstand neither higher temperatures nor high salinity conditions that are typical for many oil reservoirs. For instance, there are many deep oilfield reservoirs worldwide which demand products of long term hydrolytic and thermal stability at higher than 130 °C temperature. Current PPGs neither remain hydrated nor retain polymer integrity at these temperatures. A systematic approach was followed to develop hydrogel compositions which can withstand temperatures of at least 150 °C. A unique high temperature-resistant hydrogel composition (HT-PPG) was developed with exceptional thermal stability for more than 18 months in different brine environments. We will present the effects of salinity, pH, temperature, and multivalent ions on swelling and rheological behavior of these HT-PPGs. Phase stability of the HT-PPG was evaluated under conditions of high pressure, supercritical CO2 and concentrated acids. Core flooding is a test to confirm the conformance control suitability of HT-PPGs in reducing the effective permeability of open fractures to demonstrate porosity-plugging efficiency. HT-PPG is a nontoxic composition and a suitable candidate for conformance control operations in North Sea reservoirs.

Synthesis of monolithic porous carbon aerogels without use of supercritical fluid drying from polymer-crosslinked xerogel powders

Rushi Umeshkumar Soni, Dept. of Chem., MS&T

Abstract: Carbon aerogels are well known for their high surface areas and high porosities with applications in CO2-capture, electrodes for electrochemical cells and catalyst-supports. They are typically made by pyrolysis of carbonizable polymeric aerogels. The latter are obtained from corresponding wet-gels by replacing their pore-filling solvent with liquid CO2 that is converted to a supercritical-fluid and vented off as a gas. The high porosity of carbon aerogels is derived from both the innate porosity of the precursor polymeric aerogels, and the porosity created by the pyrolytic decomposition reactions. Here we report a new route for the synthesis of carbon aerogels from xerogel powders, which speeds-up solvent exchange processes and bypasses supercritical-fluid drying, resulting in time, energy, and materials efficient synthetic methodology.

Part-1: Amorphous carbon aerogels were prepared either via free-radical surface-initiated polymerization of acrylonitrile on the network of functionalized silica or from polyurea-crosslinked silica xerogel powders, which were compressed into pellets, aromatized, pyrolyzed and treated with HF and/or CO2 to remove SiO2 particles and/or carbon, respectively, creating high surface area and porosity.

Part-2: Graphitic carbon aerogels were prepared from metal catalyzed polyacrylonitrile-crosslinked xerogel powders at lower temperatures compared to conventional graphitization. All aerogels were characterized using powder-XRD, Raman spectroscopy, and TEM.

Spring Semester 2020

Intellectual Property Basics; Patents, Copyrights, and Trade Secrets

Lauren Hatfield, Assistant Director, Career Opt & Employer Relation, MS&T

Abstract: Career Opportunities and Employer Relations (COER) is located on the 3rd floor of Norwood Hall.  COER is dedicated to helping Missouri S&T students and alumni pursue their career goals assisting in all stages from summer internships, to co-ops and full-time employment.  Services include student advising, LinkedIn reviews, professional development workshops,
career fairs and more!

The application of Freeze-Thaw coupled with HPLC-MS/MS and SPME-GC-MS on the analysis of emerging pollutants in plant tissues

Xiaolong He, Dept. of Chem., MS&T

Abstract: Emerging and fugitive contaminants (EFCs) generated by anthropogenic activities have caused a fugitive legacy threaten to the quality and quantity of food and water, which are closely linked through plants. Therefore, it is highly desirable to enable to effectively screen the plant uptake of emerging pollutants. In this study, rapid freeze-thaw/centrifugation extraction followed by high performance liquid chromatography -tandem mass spectrometry (HPLC-MS/MS) methods were developed for determination of twelve EFCs, including Estriol, Codeine, Oxazepam, 2,4-DNT, RDX,
Acetaminophen, Bisphenol-A, Triclosan, Caffeine, Carbamazepine, Lincomycin, DEET. The methods centrifuge the sap out of the plant tissue through a molecular sieve membrane filter directly in the centrifugation tube to remove macromolecules and particulates from the sap. The sap solution can then be analyzed directly by HPLC-MS/MS. For the volatile environmental contaminants, 1,4-Dioxane and 1,2,3- Trichoropropane (1,2,3-TCP), an freeze-thaw and solid phase micro extraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS) method was developed for determination. Three different kinds of plant, i.e. corn (Zea mays), tomato (Solanum lycopersicum) and wheat (Tritcum spp) were chosen as representative plants. These methods offer ultrasensitive and very rapid green approaches to determine the EFCs
concentrations in agriculture crops, and have been applied to study the plant uptakes and distributions of the selected EFCs.

Emerging phases and phase transitions in quantum matter

Dr. Thomas Vojta, Dept. of Physics, MS&T

Abstract: Condensed matter physics deals with the complex behavior of many-particle systems. Novel phases of matter can emerge as a result of strong interactions between the constituent particles. A natural place to look for these phenomena are quantum phase transitions, the boundaries between different quantum ground states of matter. This talk first gives an introduction into quantum phase transitions and then discusses several novel phases of matter that have been discovered in their vicinity in solids and in ultracold atomic gases. These include exotic superconductors and magnets as well as Griffiths phases that are dominated by strong disorder.

What Can We Learn from Nuclear Inelastic Scattering? 

Dr. Fernande Grandjean, Dept. of Chem., MS&T

Abstract: Most solid state materials scientists are familiar with what can be learned from the recoil-free emission and resonant absorption of γ-rays, i.e., the Mössbauer-effect. However, fewer materials scientists are familiar with what can be learned from the emission and absorption of γ-rays that involves nuclear recoil, i.e., nuclear inelastic scattering. Because these γ-rays exchange energy with the solid lattice, information about the lattice vibrations can be obtained. First, this talk will briefly describe the theoretical basis of nuclear inelastic scattering and the experimental conditions required for its measurement. Second, the use of nuclear inelastic scattering of γ-rays to study lattice vibrations in thermoelectric compounds, specifically the CeFe 4 Sb 12 and EuFe 4 Sb 12 filled skutterudites will be discussed.

Mössbauer Spectral Study of the FePO4 polymorphs and Related Iron Phosphate compounds

Dr. Gary J. Long, Dept. of Chem., MS&T

Abstract: The Mössbauer spectra of trigonal α-FePO4 , the most stable polymorph of FePO4 , have been measured between 4.2 and 300 K and exhibit hyperfine parameters characteristic of high-spin iron(III) in a pseudotetrahedral oxygen coordination environment. Between 24.5 and 300K, the spectra show a paramagnetic quadrupole doublet and at 24.0 K the spectrum reveals the
onset of antiferromagnetic exchange. At 4.2 and 16 K, a single magnetic sextet is observed with hyperfine fields of 51.36(1) and 42.74 T, respectively, with an angle,  θ, of 90º between the principal axis of the electric field gradient tensor in the basal plane of the trigonal unit cell and the hyperfine field along the c-axis. The spectra obtained between 18 and 21 K have been fitted with two magnetic sextets with equal areas and with θ angles of 25 and 85º, angles which indicate that the iron(III) magnetic moments are canted away from the c-axis; the alternative symmetry lowering of the trigonal structure seems unlikely. The reduced hyperfine field versus reduced temperature plot indicates a departure from a Brillouin S = 5/2 behavior, most likely as a result of some magnetostriction at and below the Néel temperature or 24.2(2) K.
For more details see: F. Grandjean and G. J. Long, “Mössbauer Spectral Study of the Low Temperature Magnetic Properties of FePO4 and the Mixed Valence Iron(II/III) Phosphate, SrFe3(PO4)3 ,” Inorg. Chem., 58, 13314-13322 (2019).

Bioapplications of Reversible Addition-Fragmentation Chain Transfer (RAFT) Polymerization

Dr. Anthony Convertine, Materials Sci. & Eng., MS&T

Abstract: The clinical translation of nanoparticle-based therapies is challenging because of the three-dimensional structure, complex formulation parameters, as well as the multicomponent nature of these systems. In this talk we will detail the development of the polyDrug approach in which therapeutic agents and all of the functional components necessary for solubility, cell targeting, blood brain delivery, and imaging are integrated together in a single polymerization step. This
approach, which is based on the use of polymerizable prodrug monomers (Drugamers), polymerizable peptide targeting monomers (Targamers), polymerizable gadolinium chelates (Probamers), and polymerizable solubilizing monomers (Dissolvamers) overcomes the shortcomings of dispersal formulations (i.e. burst release and complex formulation steps)
allowing polyDrugs to be prepared with tunable, linear dosing profiles. We will also discuss the incorporation of Drugamers into novel nanostructured morphologies via controlled radical polymerization (CRP). Specifically, we will detail the development of radiant star single polymer nanoparticles (RSNs) via the RAFT homopolymerization of chain transfer monomers (Transmers) followed by linear polymerization from the hyperbranched cores. We will also discuss the preparation of double hydrophilic core-shell nanostructures via RAFT polymerization induced self-assembly PISA in acetic acid. Finally, we will show pH-endosomalytic segments can be integrated into these nanostructures to facilitated the
intracellular delivery of biologic drugs.

Microscale Platforms for Low-cost Chemical Analysis and Protein Separation

Dr. Keiichi Yoshimatsu, Dept. of Chem., Missouri State University

Abstract: Intermolecular interactions between molecules ubiquitously play important roles in living matters. Antibody-antigen interactions are one of the biomolecular interactions that occur in a highly specific manner. On the other hands, there are less specific biomolecular interactions that are playing critical roles (e.g. self-assembly of amphiphilic lipids into membrane structures). It appears that biological systems have adapted a various type of intermolecular interactions in order to meet different needs. Taking inspiration from nature, our group have been interested in the fundamental science on intermolecular interactions and applied research in the areas of chemical/biomolecular analysis and separation. In this presentation, I will introduce our recent efforts in applying fundamental insights on intermolecular interactions to the
development of new microscale platforms for low-cost chemical analysis, protein separation, and engineering applications.

For more information, visit the webpage here. Find an itinerary of the visit here.  

Enhancing Learning by Assessing More than Content Knowledge

Dr. Renée S. Cole, Dept. of Chem., University of Iowa

Abstract: Skills such as communication, teamwork, critical thinking, and problem solving are frequently cited as intended learning outcomes for STEM degree programs. While these skills, sometimes referred to as workplace or process skills, are highly valued, they are rarely explicitly assessed in the classroom. Assessment serves two purposes: (1) it provides a measure of achievement, and (2) it facilitates learning. The types of assessment used by an instructor also telegraphs to students what is valued in a course. However, in many instances, the lack of alignment between instructional methods and assessment detracts from the added value of engaged student learning environments. This NSF IUSE project focuses on the development and implementation of rubrics that facilitate providing feedback to students and informing the instructor as to the effectiveness of their instructional strategies in supporting process skill development. Implementation of the rubrics provides a means to better align intended outcomes with instructional activities and supports adoption of evidence-based active learning strategies that foster skill development in addition to content knowledge.

Tuesday, March 17, 9:30 – noon, Dept. Teacher Educ., Centennial Hall 103

ELIPSS Workshop: Assessing more than content knowledge

Abstract: Skills such as communication, teamwork, critical thinking, and problem solving are frequently cited as important outcomes for STEM degree programs. However, the development of these skills is often taken for granted, and they are rarely explicitly assessed in the classroom. Assessment serves two purposes: (1) providing a measure of achievement, and (2) facilitating learning by conveying what is valued in a course. This project has developed feedback-focused rubrics that serve as a resource for instructors to assess and support student skill development. In this interactive workshop, participants will work in collaborative teams to explore the meaning and role of practical skills in STEM fields, practice assessment strategies, and reflect on how the development and assessment of practical skills enhances learning. In this interactive workshop, participants will work in collaborative teams to explore the meaning and role of practical skills in STEM fields, practice assessment strategies, and reflect on how the development and assessment of practical skills enhances learning. Participants will complete a short student assignment and analyze how both content knowledge and practical skills are developed through this task. They examine how the task cues students to provide evidence of skills that could be assessed.  Participants then use ELIPSS rubrics to assess authentic student artifacts and videos of student interactions. These activities and videos are applicable and accessible to a broad range of STEM instructors provide participants with the opportunity to explore and use two student interaction rubrics (information processing and teamwork) and one product rubric (critical thinking). The teams of participants reflect on how they could elicit and assess practical skills in their own classrooms, then share ideas with the group. 

In this session, participants will:
  • ? Explore practical skills and identify how a student task might elicit evidence of these skills
  • ? Identify characteristics of student artifacts and student interactions that provide evidence of practical skills
  • ? Gain experience using rubrics to assess practical skills in student work and group interaction 

 

 

 

Ultrafast Dynamics of Photochromic Molecules

Dr. Christopher Elles, Dept. of Chem., University of Kansas

Abstract: Photochromic molecular switches are compounds that change color upon optical excitation. The color change is a response to the making, breaking, or rearranging of bonds in the molecule. We use femtosecond laser pulses to monitor these dynamics on the same timescale that the atoms rearrange. One laser pulse excites the molecule, then a second pulse probes the evolving spectrum as a function of time to reveal changes in the molecular structure. Beyond simply observing the reaction unfold, sequential excitation with two, time-delayed laser pulses allows us to control the dynamics of the molecule
and influence the outcome of the reaction. These experiments probe the potential energy surfaces that determine the motions of the atoms, and provide unique insight on the dynamics of molecules in highly excited electronic states, which is an important frontier in chemical reaction dynamics.

Fabrication technique, mechanical, and optical properties of carbon nano-onions/silica glass composites

Shuohan Huang, Dept. of Chem., MS&T

Achieving Superlubricity with 2D Transition Metal Carbides (MXenes) and MXene/Graphene Coatings

Ibrahim Abdullahi, Dept. of Chem., MS&T

Novel Aerosol Measurement Techniques for Energy and Environmental Applications 

Dr. Yang Wang, Civil, Arch., & Environmental Eng., MS&T

Designing Correlation Consistent Basis Sets for Use with Density Functionals

Dr. John Determan, Dept. of Chem., Western Illinois University 

Analytical Method Development for Biomedical and Environmental Applications

Mousumi Bose, Dept. of Chem., MS&T

Electrocatalytic processes for CO2 reduction and biomass conversion

Apurv Saxena, Dept. of Chem., MS&T

Fall Semester 2019

 

Fall 2019 (PDF)

 

 

 

General Laboratory Safety Training

Environmental Health and Safety, MS&T

General Safety

  • Environmental Health and Safety Department
  • General Rules/Policies and Prudent Practices
  • Fire Safety
  • Emergency Response
  • Hazard Communication
  • Engineering/Administrative Controls, and Personal Protective Equipment
  • Injury / Incident Reporting

Hazardous Material Safety and Management

  • Chemical/Biological/Radiological Hazards
  • Compressed Gas Cylinders / Cryogenics
  • Physical Hazards
  • Chemtrack Inventory System

 

General Laboratory Safety Training

Environmental Health and Safety, MS&T

Environmental Management System

  • ISO 14001
  • Corrective action

Hazardous Waste Management

  • Federal Regulations
  • Chemical Waste – proper storage and labeling
  • Chemical Waste – pick-up request
  • Biological Waste
  • Universal Waste
  • Spill Response

Development of real-time PCR assays to detect and identify foodborne pathogen threat agents

Dr. Kelly Elkins, Dept. of Chemistry, Towson University, Towson, MD

Abstract: Foodborne pathogens including Escherichia coli, Salmonella enterica, Shigella flexneri, Listeria monocytogenes, Vibrio parahaemolyticus, and Clostridium difficile routinely cause foodborne illness in the United States reported by the Centers for Disease Control and Prevention (CDC). Foods including uncooked or undercooked meats and shellfish, salads can cause illness. The CDC classifies these as bioterrorism threat agents and rapid, specific and sensitive assays are essential for identification and treatment. Several of these pathogens are classified in the CDC's Category B, or second highest priority, as they can be disseminated with moderate ease, require enhanced disease surveillance and result in moderate morbidity and low mortality rates. Salmonella was used to intentionally contaminate an Oregon salad bar, creating the largest incidence of foodborne pathogen illness in the U.S. in 1984 and S. flexneri was used to contaminate donuts in a hospital break room in Texas in 1997. In this presentation, I will describe the development of new polymerase chain reaction (PCR) high resolution melt (HRM) assays to detect and identify these food-borne pathogens by the different melt temperatures of the amplified DNA. Developmental validation results including reproducibility, specificity, sensitivity, and robustness will be presented. Experiments demonstrating the performance of multiplex assays targeting multiple pathogens simultaneously will also be presented.

For more information, visit the webpage here. Find the itinerary of the visit here. 

 

Three-Dimensional Nanotube Arrays for Solar Energy Harvesting and Production of Solar Fuels

Dr. Wipula P. Liyanage, Dept. of Chemistry, MS&T

Abstract: Fabricating high-efficiency photovoltaic devices largely rely on nanostructuring the photoabsorber layers due to the ability of improving photoabsorption, photocurrent generation and transport in nanometer scale. Vertically aligned, highly uniform nanorods and nanowire arrays for solar energy conversion have been explored as potential candidates for solar energy conversion and solar-fuel generation owing to their enhanced photoconversion efficiencies. However, controlled fabrication of nanorod and especially nanotube arrays with uniform size and shape and a pre-determined distribution density is still a significant challenge. In this talk, we demonstrate how to address this issue by fabricating nanotube arrays by confined electrodeposition on lithographically patterned nanoelectrodes defined through electron beam as well as nanosphere photolithography. This simple technique can lay a strong foundation for the study of novel photovoltaic devices because successful fabrication of these devices will enhance the ability to control structure-property relationships. The nanotube patterns fabricated by this method could produce an equivalent amount of photocurrent density produced by a thin film like device while having ~ 10% of semiconducting material coverage. This talk also focuses on solar fuel generation through photoelectrocatalytic water splitting for which efficient electrocatalysts were developed from non-precious elements.

 

Interface Engineering for Lithium-Ion Batteries

Dr. Jonghyun Park, Mech. & Aerospace Engineering, MS&T

Abstract: Battery performance is highly dependent on the interfacial phenomena among the components of the battery materials. This talk introduces the key interfacial physics on anode and cathode particles, and the engineering process that controls their behavior towards improved battery performance. The dissolution of the active materials and the instability of the Solid Electrolyte Interphase (SEI) are two of the key phenomena responsible for the degradation. These two phenomena, in particular, cannot be considered independent at elevated temperatures, since a significant amount of the ions dissolved at elevated temperatures move to the anode side and modify the SEI layer. The findings on the chemical degradation of the SEI layer induced by dissolved Mn ions and its mechanism through XPS and AFM will be discussed. Further, the use of electrolyte additives is one of the most effective and economical ways to improve battery performance by stabilizing the electrode/electrolyte interface. The impact of fluoroethylene carbonate (FEC), which was found to have different impacts on anode and cathode, will be  discussed. In this talk, the study on composition-/structure-dependent elasticity of the SEI layer via AFM measurements coupled with XPS analysis, and atomistic calculations will be discussed.

Novel Analytical Methods for Anticancer Drug Discovery by Using High-Resolution Mass Spectrometry

Ke Li, Dept. of Chemistry, MS&T

Abstract: Cancer is a major public health concern and one of the leading cause of death. Millions of people were diagnosed with cancer each year. Many cancers such as lung cancers and brain cancers, the 5-year survival rate is pretty low, less than 20%. Currently, traditional chemotherapy is still the predominant therapy for many cancers. However, the severe side effects are the common problems due to the non-selectivity of the chemotherapy drugs. Therefore, developing new targeted anticancer drugs to lower the systematic toxicity are in high demand. During any anticancer drug discovery, advanced analytical technology must be used to characterize the structures of the drugs and evaluate the effectiveness of the drugs. High resolution mass spectrometer (HRMS) is a powerful technology and is often used for the new anticancer drug discovery. The high resolution, high mass accuracy, multiple mode of fragmentation and capability of coupling to liquid chromatography make it an indispensable instrument for qualitative and quantitative analysis in anti-cancer drugs discovery. In this presentation, several novel HRMS analytical methods will be introduced and applied for discovery of new targeted anticancer drugs including antibody−drug Conjugates and small molecule drug. The detailed experimental conditions and results will described in my presentation. 

Folding- and Dynamics-based Electrochemical Biosensors

Dr. Rebecca Y. Lai, Dept. of Chem., University of Nebraska-Lincoln

Abstract: This seminar will cover the recent advances in the design and fabrication of folding- and dynamics-based electrochemical biosensors. These devices, which are often termed electrochemical DNA (E-DNA), aptamer-based (E-AB), and peptide-based (E-PB) sensors, are fabricated via direct immobilization of a thiolated and methylene blue (MB)-modified oligonucleotide or peptide probe onto a gold electrode. Binding of an analyte to the probe changes its structure and/or flexibility, which, in turn, influences the electron transfer between the MB label and the interrogating electrode. These sensors are resistant to false positive signals arising from the non-specific adsorption of contaminants, and perform well even when employed directly in whole blood, saliva and other realistically complex sample matrices. Furthermore, because all of the sensing components are chemisorbed onto the electrode surface, they are readily regenerable and reusable. Our results show that many of these sensors have achieved state-of-the-art sensitivity, while offering the unprecedented selectivity, reusability and operational convenience of direct electrochemical detection.

Nanomaterial Assembly & Analytical Characterization

Dr. Wenyan Liu, Dept. of Chemistry, MS&T

Abstract: Nanotechnology- the manipulation of tiny elements, is bringing amazing impact on our daily lives and is helping to improve, even revolutionize, many technologies including material science, energy, biomedicine, food safety, and environmental science. Therefore, the development of novel nanomaterials and the characterization of those tiny nanoparticles are critically important in those fields. First, I present the bottom-up assembly of nanoparticles forming novel nanostructures. Fabrication of nanoparticles into superstructures has attracted tremendous research interest due to their interesting collective properties different from those of individual components or their randomly packed aggregates. DNA-mediated self-assembly is one of the most widely used approaches in nanoparticle superlattice construction, which has led to the realization of various superlattices. However, effective assembly of prescribed nanoparticle superstructures remains a difficult challenge. This presentation will demonstrate our efforts on how to use DNA origami nanostructures, serving as both topological linkers and symmetry breakers, to facilitate the synthesis of tailor-made nanoparticle super-architectures. Examples include the creation of polychromatic nanoparticles for assembly of arbitrarily shaped nanostructures and the construction of low-coordinated diamond-type superlattices from gold nanoparticles. Following this, I talk about the characterization of nanoparticles by using state-of-the-art bioanalytical tools: the detection of nanoparticles in soil via single particle (SP)-ICP-MS.

 

Next-generation Battery Technologies

Dr. Arumugan Manthiram, Mechanical Engineering & Materials Sciences & Engineering, University of Texas-Austin

Abstract: Rapid increase in global energy use and growing environmental concerns have prompted the development of clean, sustainable, alternative energy technologies. Renewable energy sources like solar and wind are a promising solution, but electrical energy storage (EES) is critical to efficiently utilize them as they are intermittent. EES is also the only viable near-term option for transportation. Rechargeable batteries are prime candidates for EES, but their widespread adoption for electric vehicles and grid electricity storage requires optimization of cost, cycle life, safety, energy density, power density, and environmental impact, all of which are directly linked to severe materials challenges. After providing a brief account of the current status, this presentation will focus on the development of advanced materials and new battery chemistries. Specifically, lithium-based batteries based on low-cobalt oxide and sulfur cathodes and interdigitated alloy anodes will be presented. The challenges of bulk and surface instability and chemical crossover during charge-discharge cycling, advanced characterization methodologies to develop an in-depth understanding, and approaches to overcome the challenges will be presented.

 

Synthesis, Characterization and DSC and TGA Investigation of a Colloidal Unimolecular Polymer

Peng Geng, Dept. of Chemistry, S&T 

Abstract: CUP particles are unimolecular spheroidal particles suspended in water and are thermodynamically stable. CUP size is directly related to the molecular weight and are typically between 2.5 and 9 nm in diameter. The surface of these particles per gram is extremely large. Since any surface in contact with water will have a layer of “surface” or associated water on it. The surface water has different physical properties than bulk water. Differential scanning calorimetry (DSC) can determine the free versus surface water based upon the heat of fusion since only free water freezes at zero, giving an estimation of the thickness of surface water by measuring the heat of fusion. Using this data calculation of the specific heat of surface water; determination of the average surface area of functional groups on the CUP surface by knowing the freezing point depression of CUP suspensions; establishment of a relationship between CUP surface water, the molecular weight and ions per nm of surface area. TGA was then used to investigating the evaporation rate for colloidal unimolecular polymer systems. CUP solutions from 5-25% solution up to the point when the gelation occurs. Various models were explored to understand how water evaporates as a function of time, temperature, molecular weight, charge density and ionic group.

 

 

Applications of the confocal microscope for chemistry and biology

Dr. Katie Shannon, Dept. of Biology, MS&T

Abstract: Confocal microscopy allows for improved imaging of thick samples due to reduction of out-of-focus light. In this seminar, the principles of confocal microscopy will be discussed, and examples of applications in chemistry and biology provided. Attendees will learn about the capabilities of Missouri S&T’s Nikon A1R laser scanning confocal microscope and how this instrument could benefit their research. 

Ultrafast Dynamics of Photochromic Molecules

Dr. Christopher Elles, Dept. of Chem., University of Kansas

AbstractPhotochromic molecular switches are compounds that change color upon optical excitation. The color change is a response to the making, breaking, or rearranging of bonds in the molecule. We use femtosecond laser pulses to monitor these dynamics on the same timescale that the atoms rearrange. One laser pulse excites the molecule, then a second pulse probes the evolving spectrum as a function of time to reveal changes in the molecular structure. Beyond simply observing the reaction unfold, sequential excitation with two, time-delayed laser pulses allows us to control the dynamics of the molecule and influence the outcome of the reaction. These experiments probe the potential energy surfaces that determine the motions of the atoms, and provide unique insight on the dynamics of molecules in highly excited electronic states, which is an important frontier in chemical reaction dynamics.

Lab-in-a-Particle: Enginnering Nano- and Microparticles to Combat Infectious Diseases

Dr. Sutapa Barua, Dept. of Chemical and Biochemical Engineering, MS&T

Abstract: Non-spherical drug nanoparticles selectively invade and kill cancer cells by enhancing multivalent receptor-ligand interactions. Breast cancer cells overexpress human epidermal growth factor 2 (HER-2) receptor proteins that are targeted for selective binding using Trastuzumab, a humanized IgG monoclonal antibody from Genentech. Trastuzumab- conjugated shape-engineered drug nanoparticles are shown to enhance multivalent interactions with breast cancer cells, release cytotoxic drug molecules and induce a significant reduction in the cancer cell population.
In a second project, we have demonstrated for the first time the effective removal of endotoxins from pharmaceutical formulations using polymer nanoparticles. The nanoparticles are shown to remove >99% endotoxins from pharmaceutical protein formulations with >99% product recovery.
We have also developed a technology to grow mammalian cells on the surface of biodegradable microparticles in liquid cell culture suspension for traumatic burn injury. An overview of this lab-in-a-particle approach will be presented as a suitable and cost-effective way to carry out treatment and prevention for a range of human diseases.

Novel Transition Metal Catalysts for the Intermolecular Amination of Light Alkanes and Benzenes

Meenakshi Mehta, Dept. of Chemistry, MS&T

Abstract: Transition metal catalyst frameworks supported by tripodal [N3N] ligands mediate nitrene transfer from nitrogen sources such as PhI=NR to a diverse group of aliphatic and aromatic hydrocarbons and olefins. These reactions are categorized as amination and aziridination reactions. Novel tripodal ligands and their complexes with late first- and second-row transition metals (Cu, Ag) with different axial atoms such as B, Si, CH, and 2,4,6-substituted benzene systems have been designed to impart weaker axial ligand field which in turn enhances the electrophilicity of nitrene potentially affording more reactive and site-selective aminated products. Synthetic efforts to generate these ligands as well as novel Z-type ligands featuring heavier Group 15 elements (Sb, Bi) placed on the axial apex of a tripodal ligand scaffold will be discussed in detail.

Spring Semester 2019

Intellectual Property Basics; Patents, Copyrights, and Trade Secrets

Keith Strassner, Assistant Vice Provost for Technology & Business Development, MS&T

Abstract:  Intellectual property issues are constantly in the news – the Apple vs. Samsung, Alice Corporation vs. CLS, Myriad – these legal cases are just a few of those that have had and will have a significant impact on how universities and companies built on technology will conduct business in the future. In the Myriad case, the US Supreme Court ruled that naturally occurring genes and their uses cannot be patented, Alice vs. CLS will set a new standard for patentability of software code and so-called business method patents; think Amazon one-Click® method. In today’s technology based world, it is critical to have a basic understanding of the types of intellectual property, how they are created and protected. This talk will explore patents, copyrights, trademarks and trade secrets. In addition, intellectual property policy within the University setting will be described.

Structure Determination of Five-membered Silene Rings Using Microwave Spectroscopy

Frank Marshall, Grad. Stud., Dept. of Chem., MS&T

Abstract:  Rotational spectroscopy relates the rotational energy transitions of a gas phase molecular system to the locations of atoms utilizing mass displacement throughout the system. These separations are generally low in energy and fall in the microwave (3-300 GHz) region of the electromagnetic spectrum, leading the phrase “rotational spectroscopy” to be termed “microwave spectroscopy.” A brief introduction to microwave spectroscopy will be provided. Spectrometers of this sort cannot be purchased, so the construction and implementation of a chirped-pulse, Fourier transform microwave (CP-FMTW) spectrometer will be discussed. Because not all desired systems are gas phase, various sourcing techniques to get liquids or solids into the gas phase on the CP-FTMW will also be presented and discussed. As an example of the usefulness of these experimental techniques, the rotational spectra of four 5-membered Silane rings (1,1-di?uorosilacyclopent-3-ene, silacyclopent-3-ene, 1,1-di?uorosilacyclo-pentane, and 1,1di?uorosilacylopent-2-ene) was observed, collected, and analyzed. The molecules were observed in the 6 to 18 GHz range of the electromagnetic spectrum. Isotopic substitution spectra for many of these molecules have been obtained in natural abundance and been used to identify differences in molecular structure amongst the family. These differences in structure will be presented, showing how different functional groups and bond locations affect the overall structure and behavior of each system both quantum chemically and mechanically (ring puckering effects, etc….). These effects will then be compared to 6 membered Silane rings with similar functional groups. The behavior between the 5 and 6-membered families will be analyzed and presented.

Hydrogen Tunneling at Metallic Active Sites

Dr. Darrin Bellert, Dept. of Chemistry, Baylor University

Abstract:  From cracking or reforming in the oil industry to the activity of metalloenzymes, metal mediated catalysis is pervasive throughout society.  The reason for this is the energy cost reduction that catalysis affords during chemical transformations.  It is commonly understood that an active site provides alternant, lower energy pathways to a chemical reaction thus subverting the total energy cost associated with crossing over an activation barrier.   But what are these alternant pathways? 

    This talk discusses the possibility of hydrogen atom tunneling as another mechanism to lower the energy requirements of metal mediated catalysis.  Several years ago, the Bellert group at Baylor University developed a novel method to measure the kinetics and dynamics of gaseous metal mediated reactions.  The single photon initiated dissociative rearrangement reactions (SPIDRR) technique has been applied to various metal mediated reactions with results that defy contemporary (transition state theory or over the barrier) interpretations.  This talk will explore the possibility of hydrogen atom tunneling as the controlling kinetic paradigm in certain metal mediated reactions. 

Synthesis of Tripodal Based Chiral Framework Guanidines

Anshika Kalra, Grad. Stud., Dept. of Chem., MS&T

Abstract:  Part 1Comparative Nitrene-Transfer Chemistry to Olefinic Substrates Mediated by a Library of Anionic Mn(II) Triphenylamido-Amine Reagents and M(II) Congeners (M = Fe, Co, Ni): An Experimental and Computational Study. Aziridination of styrenes is examined via anionic MII catalysts (M= MnII, FeII, CoII, and NiII), supported by trisamido-amine moieties through a nitrene transfer reaction. We demonstrated that attenuated levels of electrophilicity are more suitable for discriminating aromatic from aliphatic olefins for aziridination purposes. The high-spin nature of the compounds encountered in the present work gives rise to putative metal-nitrene intermediates possessing more complex electronic structures than the common singlet/triplet manifolds explored with Cu, Ag or Ru nitrenes. We concluded – from experiments and computations – that carboradical intermediates are generated by initial nitrene-addition to one of the olefinic carbons, and play a key role in the stepwise C−N bond?formation. In this combined experimental and computational study, we present a family of anionic Mn(II) reagents that offer guidance with regards to ligand selection for effecting olefin aziridination, and subsequently extend to the corresponding Fe(II), Co(II), and Ni(II) reagents to gain insights in their comparative reactivity/selectivity patterns that enable aromatic over aliphatic alkene aziridinations.

    Part 2:  Enantioselective, Intermolecular Aziridination of Alkenes and Amination of Alkanes Catalyzed by Metal Reagents Supported (Cu, Ag) by Tripodal Ligands with a Chiral Framework. C-H and C=C bonds are ubiquitous structural units of organic molecules. Although these bonds are generally considered to be chemically inert, the recent emergence of methods for C-H and C=C functionalization seems to be quite promising. The intermolecular amination of C-H bonds and aziridination of C=C bonds represents a particularly desirable and challenging transformation. Recognizing the potential of this transformation we are currently developing guanidine based chiral ligands and catalysts for intermolecular C-H Amination and C=C Aziridination.

Guanidines are known as powerful organic bases and act as base catalysts in a variety of organic synthetic reactions. Introduction of chiral centers at the guanidinyl moiety can create new types of chiral organocatalysts.  We have prepared several types of guanidine compounds with chiral centers and are examining their catalytic activity in asymmetric intermolecular C-N bond synthesisEnantioselecive intermolecular C-H amination and C=C aziridination via the generation and transfer of metal nitrenoids is under development using Cu (I) and Ag (I) catalysts.

Smart Materials for Energy Conversion: The Story of Transition Metal Chalcogenides

Dr. Manashi Nath, Associate Professor, Dept. of Chem., MS&T

Abstract: This talk will focus on the elucidating a proper understanding of the structure-property correlation of transition metal chalcogenides and employing concepts of solid state chemistry to design optimal nanostructured electrocatalysts for application in energy conversion technologies. Energy harvesting from solar and water has created ripples in solid state materials chemistry research for the last several decades, complemented by the rise of Hydrogen as a clean fuel. Another aspect that has become more relevant is the electroreduction of atmospheric carbon dioxide into fuel or other value-added chemicals, thereby offering environmental remediation without the need to store large amounts of pressurized CO2. It has become very apparent that hydrogen-on-demand technology needs to be developed to complement the growth of hydrogen fuel economy without adding on to the process cost by storing hydrogen in pressurized tanks or non-reactive framework. In this regard, water electrolysis leading to generation of oxygen and hydrogen on demand, has been one of the most promising routes towards sustainable alternative energy generation and storage without depleting fossil-fuel based natural resources. However, the efficiency and practical feasibility of water electrolysis is limited by the anodic oxygen evolution reaction (OER), which is a kinetically sluggish, electron-intensive uphill reaction. A slow OER process also slows the other half-cell reaction, i.e. the hydrogen evolution reaction (HER) at the cathode. Hence, designing efficient catalysts for OER and HER process from earth-abundant resources has been one of the primary concerns for advancing solar water splitting. In the Nath group we have focused on transition metal chalcogenides nanostructures as efficient electrocatalysts for several energy conversion processes. In this talk we’ll discuss the design principles illustrating with several examples of new catalyst compositions discovered in the laboratory.

Zintl Phases for Thermoelectric Applications

Dr. Susan Kauzlarich, Dept. of Chemistry, Univ. of California-Davis

Abstract:  There are many areas of science where progress is materials limited. The synthesis and identification of new compounds that can lead to enhancements in existing technologies, or serve as the basis of revolutionary new technologies, is essential for developing new and improved technologies. Zintl compounds can be described by a combination of ionic and covalent bonding, composed of electropositive cations which donate electrons to the more electronegative components that utilize the electrons to form various bonding motifs. My group has focused on Zintl compounds for their structural, chemical, and electronic properties and I will present research on Zintl phases for thermoelectric applications such as waste heat to electrical power conversion.

Inelastic Collisions of Ozone and Argon

Sangeeta Sur, Grad. Stud., Dept. of Chem., MS&T

Abstract:  The formation and destruction of ozone is an important cycle in the atmosphere. An important step in the formation process is the stabilization of a metastable ozone molecule, which occurs through energy transfer: usually a highly excited ozone molecule loses the extra energy through collision with a third body. However, the details of this mechanism are still not well known and one of the reasons is the lack of an accurate potential energy surface (PES). In theoretical studies, Ar is often selected as the third body when considering the dynamics. However, there are no reported electronic structure calculations for the PES of the O3 - Ar complex. The PES of the O3-Ar complex is a 6D problem in full-dimensionality, or 3D for rigid O3. Here I present global 3D PESs for O3 fixed at equilibrium, interacting with Ar. Ab initio electronic structure calculations using explicitly-correlated coupled-cluster (CCSD(T)-F12b) extended to the complete basis set limit, and explicitly-correlated multi-reference configuration interaction (MRCI--F12) were employed. The AUTOSURF code was used to construct the PESs automatically, represented by a local interpolating moving least-squares (L-IMLS) method. Global RMS fitting errors of less than 1 cm–1 were obtained. Symmetry equivalent minima with a well depth of –229 cm–1 are located above and below the plane of O3. I will present bound state calculations of the O3-Ar vdW complex obtained by variational rovibrational calculations, as well as results of quantum scattering studies for rotationally inelastic collisions. The isotopic effect is also studied using the 16O18O16O and 16O16O18O isotopologues. Moving from a symmetric system to an asymmetric one, roughly a doubling in the density of states is observed due to nuclear spin statistics.

Advanced Pulse Techniques for Analysis and Compensation of Inhomogeneous Magnetic Fields in NMR Spectroscopy

Emma Schmittzehe, Grad. Stud., Dept. of Chem., MS&T

Abstract:  NMR pulse sequences are continuously being designed both to improve the current capabilities as well as to provide for new applications. In this process theoretical methods ranging from the simple vector model to more involved density matrix calculations and product operator formalism are used to predict the fate of the magnetization that will be observed with NMR. However, the reliability of NMR pulse sequences is critically dependent on the accuracy of the radiofrequency (RF) pulses, and the inaccuracies of the RF pulses are not always obvious or predictable. A new imaging protocol has been developed to independently record the x, y, and z components of the net magnetization during any point in a pulse sequence while eliminating the observation of the other components. This protocol provides an experimental method of tracking magnetization which then can be used in conjunction with theoretical methods to scrutinize the predicted outcome of each step in a pulse sequence and potentially find further improvements to the effectiveness and efficiency of NMR pulse sequences. The protocol utilizes a Rapid rotating-frame Imaging Pulse Train (RIPT) on a sample with a single resonance (e.g., CHCl3) to obtain RF-field (B1) and resonance-offset (ΔB0) dependent profiles for each Cartesian component in the magnetic coordinate system.

Folding- and Dynamics-based Electrochemical Biosensors

Dr. Rebecca Y. Lai, Dept. of Chemistry, Univ. of Nebraska-Lincoln

Abstract:  This seminar will cover the recent advances in the design and fabrication of folding- and dynamics-based electrochemical biosensors. These devices, which are often termed electrochemical DNA (E-DNA), aptamer-based (E-AB), and peptide-based (E-PB) sensors, are fabricated via direct immobilization of a thiolated and methylene blue (MB)-modified oligonucleotide or peptide probe onto a gold electrode. Binding of an analyte to the probe changes its structure and/or flexibility, which, in turn, influences the electron transfer between the MB label and the interrogating electrode. These sensors are resistant to false positive signals arising from the non-specific adsorption of contaminants, and perform well even when employed directly in whole blood, saliva and other realistically complex sample matrices. Furthermore, because all of the sensing components are chemisorbed onto the electrode surface, they are readily regenerable and reusable. Our results show that many of these sensors have achieved state-of-the-art sensitivity, while offering the unprecedented selectivity, reusability and operational convenience of direct electrochemical detection.

Synthesis of Ceramic and Metal Aerogels from Xerogels and Applications in High Temperature Thermal Insulation and Thermites

Parwani Rewatkar, Grad. Stud., Dept. of Chem., MS&T

Nitrogen-phosphorus-associated Metabolic Activities During the Development of a Cyanobacterial Bloom Revealed by Metatranscriptomics

Dr. Jingrang Lu, National Exposure Research Lab., EPA, Cincinnati

Abstract:  This seminar will cover the latest discoveries of association of cyanobacteria-caused harmful algal blooms (CyanoHAB) with nitrogen and phosphorus, especially the impact of ammonium on CyanoHAB). Our study demonstrated that expressions of genes involved in N2-fixation (nifDKH) and P-scavenging were significantly upregulated during the bloom compared to pre-bloom in Harsha Lake. The activities of N2-fixation occurred during early summer after a late spring phytoplankton bloom, and were associated with high phosphorus and low nitrogen. The highly active cyanobacterial N2-fixers were dominated by Nostoc and Anabaena. Following the activities of N2-fixation and production of new nitrogen, an early summer Microcystis-dominated bloom, a shift of dominance from Nostoc and Anabaena to Microcystis and an increase of microcystin occurred. By contrast, P-scavenging activities dominated also by Nostoc and Anabaena were associated with low P and the Microcystis bloom. This information can be used to aid in the understanding the impact that nitrogen and phosphorus have on the early summer CyanoHAB and the functional activities of Nostoc- and Anabaena-dominated or Microcystis-dominated communities, and aid in making management decisions related to harmful algal blooms.

DNA Engineering: Application from drug delivery to plasmonic metamolecules

Dr. Risheng Wang, Assistant Professor, Dept. of Chem., MS&T

Abstract:  DNA (deoxyribonucleic acid), the natural hereditary material in humans and almost all other organisms, can be fabricated into functional nanostructures through Watson-Crick base paring in biochemistry and engineering fields. Over the past four decades, researchers in the emerging field of DNA nanotechnology have synthesized a diversity of DNA nanostructures with excellent programmability, biocompatibility, and low/no cytotoxicity. These self-assembled nanostructures have been used to precisely organize functional components into deliberately designed patterns, which exhibit a wide range of applications in material science, biomedical, electric and environmental fields.  In this talk, I will present our efforts in the design and construction of several DNA nanostructures for nanotechnology and biomedical applications. For example, DNA origami-assisted cancer drug delivery, integrated hydrogen peroxide biosensing, self-assembled plasmonic metamolecules, and stimuli-responsive DNA nanostructures.

Mechanically Strong and Transparent Silica Aerogel for Applications in Thermally Insulated Windows

Chandana Mandal, Grad. Stud., Dept. of Chem., MS&T

Abstract:  A hypothesis that is under intense current investigation by the scientific community states that the mechanical properties of nanostructured polymers depend on their nanomorphology. Aerogels are nanostructured ultra-lightweight nanoporous materials with skeletal frameworks that can display a wide range of nanomorphologies. Thereby aerogels comprise a suitable platform for testing not only that hypothesis but also a wide range of other properties such as light scattering for applications, for example, in thermally insulating windows.

To study the mechanical properties of nanostructured matter as a function of nanomorphology, various shape-memory polyurethane aerogels were prepared with identical density, porosity, and chemical composition, but with vastly different nanostructures. That was accomplished based on our understanding that nanostructure is intimately related to the rate of gelation, which in turn was controlled by developing an array of new catalysts, some much more and some less active than the classic Sn-based dibutyltin dilaurate used in polyurethane synthesis. Depending on the gelation time, the morphology ranged from spheroidal to bicontinuous. Irrespective of the catalyst and its concentration, the morphology was the same for equal gelation times pointing to chemical cooling-induced spinodal decomposition as the gelation mechanism.  Based on 5 different catalysts at 5 different concentrations each, the elastic modulus of all materials followed a well-defined trend whereas, all other factors being equal, bicontinuous structures were by several times stiffer than spheroidal nanostructures, in strong support of the standing hypothesis above.

In order to develop silica aerogels as thermal insulators for windows, one must achieve a balance of clarity, strength, and thermal insulation value. The combination of the three properties was studied by applying statistical design of experiments methods on the synthesis of polymer-crosslinked silica aerogels with the concentrations of the silica precursor and the monomer of the crosslinking polymer as explanatory (independent) variables. Light scattering (haze) was studied with an integrating sphere, thermal conductivity with the hot plate method and mechanical strength with uniaxial compression. Along the way, the source of haze was identified with light scattering from secondary silica particles. Delamination of wet-gels from glass substrates during drying into aerogels was traced to the nature mass fractal of the secondary particles that allows them to merge with one another.  Based on these data, optimal synthetic and processing conditions were identified.

Fall Semester 2018

Ionic Liquids in Separations and Mass Spectrometry

Daniel W. Armstrong, University of Texas at Arlington

Abstract: Room-temperature ionic liquids (RTILs), are a class of nonmolecular ionic solvents with low melting points. Most common RTILs are composed of unsymmetrically substituted nitrogen-containing cations (e.g., imidazolium, pyrrolidinium, pyridinium) or phosphonium cations with inorganic anions (e.g., Cl?, PF6?, BF4?). Most of these more common ILs are of limited use analytically. Consequently many ILs containing a variety of cations and anions of different sizes have been synthesized to provide specific characteristics. In this presentation an overview of the structure and properties of ILs and a description of their expanding use in various applications in separations, chromatography and mass spectrometry will be given. A number of studies have appeared indicating that ILs have exceptional promise as stationary phases. They have a dual nature selectivity in that they separate nonpolar molecules as would a nonpolar stationary phase and they separate polar molecules as would a polar stationary phase. Many ILs have exceptional thermal stability. They are being used increasingly in a variety of applications including 2-D GC, enantiomeric separations, the measurement of water in samples/solvents/materials and compact field GC units. ILs have proven to be the best liquid MALDI-MS matrix since we introduced them as such a few years ago. The properties of ILs that make them effective will be discussed.  Further, the dications developed for high stability ILs have found another novel use in electrospray ionization (ESI) MS as a reagent for ultra sensitive anion analysis.  These will be discussed as well.

General Labratory Safety Training: Safety

Environmental Health and Safety, MS&T

Abstract: 

  • General Safety
    • Environmental Health and Safety Department
    • General Rules/Policies and Prudent Practices
    • Fire Safety
    • Emergency Response
    • Hazard Communication
    • Engineering/Administrative Controls, and Personal Protective Equipment
    • Injury / Incident Reporting
  • Hazardous Material Safety and Management
    • Chemical/Biological/Radiological Hazards
    • Compressed Gas Cylinders / Cryogenics
    • Physical Hazards
    • Chemtrack Inventory System

 

General Labratory Safety Training: Environmental Compliance

Environmental Health and Safety, MS&T

Abstract: 

  • Environmental Management System
    • ISO 14001
    • Corrective action
  • Hazardous Waste Management
    • Federal Regulations
    • Chemical Waste – proper storage and labeling
    • Chemical Waste – pick-up request
    • Biological Waste
    • Universal Waste
    • Spill Response

Analysis of Inorganic and Organic Water Contaminants by Mass Spectrometry

Ariel Donovan, Dept. of Chem., MS&T & Organic Geochemistry Research Laboratory, Lawrence, KS

Abstract: Water quality is imperative to preserve human, animal, and environmental health and can be impacted by a variety of contaminants including inorganic and organic constituents. They can be naturally occurring or anthropogenically introduced or influenced. This seminar will discuss two types of water contaminants; nanoparticles and algal and cyanotoxins. Nanoparticles (NPs) studied include those that are comprised of metals and metal oxides that have at least one dimension less than 100 nm. They are used in many commercial and industrial applications including food packaging, antimicrobial socks, and paint/coatings. The toxicology of these materials is controversial; thus, developing tools to monitor their introduction into recreational and drinking waters is important. Single particle – inductively coupled plasma – mass spectrometry (SP-ICP-MS) methods were developed to assess the presence of five commonly used NPs in natural water and after coagulation processes, commonly used methods to remove particulate material from influent water. In the second part of the seminar, the analysis of toxins produced by cyanobacteria and algae at the land-sea interface will be discussed. Cyanobacteria are commonly known to proliferate in freshwater systems, but there is growing evidence that cyanotoxins are present along with algal toxins in coastal systems. This poses another potential exposure risk for humans, animals, and aquatic life. Advantages and limitations of the analytical techniques will be discussed, as well as results from select studies.

Highly Accurate Thermochemical Computations of Combustion and Atmoshperic Species: Comparisons with Active Thermochemical Data

Bradley Welsch, Dept. of Chem., MS&T 

Abstract: The Active Thermochemical Tables (ATcT) have been said to be one of the greatest advances in thermochemistry in the last thirty years. The ATcT is a self-consistent thermochemical network that provides thermochemical values and uncertainties that are more accurate than any individual experiment. The ATcT can consider multiple sources of thermochemical values including those generated by computation. The ATcT is valuable beyond its role in thermochemistry, because it also serves to benchmark high accuracy computational methods under development. These benchmarks allow for the assignment of uncertainty to these computations, something not commonly studied over wide classes of systems.

High accuracy computational thermochemistry involves generate multiple inputs and running several codes. If done manually there is a possibility of human error. This has motivated work on a family of codes that, starting from an approximate initial geometry, will generate the necessary input for each step, execute each calculation and, once done, process them and combine the results to produce an enthalpy of formation. Work on a second generation of a more flexible and all-one-package will also be discussed. This first generation of code has been used to generate accurate thermochemical data with a user-defined scheme for a large family of 60 molecules up to fluorobenzene. This family was also used to generate very accurate data for the alkyl peroxy family of molecules and data from these computations was used to update the thermochemical network to include this new knowledge.

Designing Bifunctional Catalyst Composites for Oxygen Evolution and Oxygen Reduction Reactions

Siddesh Umapathi, Dept. of Chem., MS&T 

Abstract:  Water splitting is one of the cleanest methods to produce hydrogen with less environmental impact. However, the efficiency and practical feasibility of water electrolysis is limited by the anodic oxygen evolution reaction (OER) which is a kinetically sluggish, electron-intensive uphill reaction. Hence finding appropriate earth abundant and environmentally benign materials for electrocatalytic water splitting has become critical for renewable energy technologies. In spite of tremendous efforts to develop a catalyst with low cost, high activity and stability, it remains a challenge to match the performance of platinum group catalyst. Hence, designing an efficient catalyst for this energy demanding process has been primary focus for advancing the technology of producing hydrogen and oxygen from water. In this presentation hybrid composites containing iron nickel selenide (FeNi2Se4) nanoparticles supported on nitrogen doped reduced graphene oxide (N-rGO), i.e., FeNi2Se4-NrGO, and iron cobalt selenide (FeCo2Se4) supported on functionalized nanoonions (FeCo2Se4-NH2-OLC) will be discussed as efficient and dependable electrocatalysts for oxygen evolution reaction (OER) under alkaline conditions. The constructed hybrid catalyst composites were capable of catalyzing water oxidation at a small overpotential and exhibited extended stability in harsh conditions. Presence of carbonaceous composite in the matrix also yielded high current density. Additionally, the catalysts also showed good activity for oxygen reduction reaction (ORR) which is the primary reaction occurring in the fuel cell. This study gives a new direction to design the selenide based bifunctional hybrid catalyst composites, which can be extended to prepare other ternary based selenide catalyst composites for a broad range of energy conversion and storage applications.

Anecdotes for the Lifetime Experiences of a 96 Year Old Emeritus Professor of Chemistry

William J. James, Dept. of Chem., MS&T 

 

Topological Superconductors

Yew San Hor, Dept. of Physics, MS&T

Abstract: Topological superconductors are predicted to have a full superconducting pairing gap in the bulk and gapless surface states consisting Majorana fermions which are spinless quasiparticles with no charge. This Majorana fermionic surface state, if detectable, could be useful for quantum computer. However, topological superconductors and the associated Majorana quasiparticles have not been conclusively established in real materials so far. This presentation will show by chemical doping, a topological insulator can be tuned into a bulk superconductor that could be a candidate for topological superconductor. The first example i.e. CuxBi2Se3 was discovered few years ago to be a promising one. Recently, SrxBi2Se3 and NbxBi2Se3 are found to be other promising systems for the topological superconductivity studies. Several other promising candidates of topological superconductors will be shown.

 

History and Restoration of the Rolla Mural

Dan Woodward, Rolla Artist, Member of American Association of Art Conservation

Abstract: In 1952 Edward Sower, Publisher of the Rolla Daily News, commissioned a mural about Rolla, its creation and history, by Sidney Lawson, a student of Thomas Hart Benton. The mural hung for more than 60 years in the Rolla Daily News building in Rolla and suffered from cigarette smoke and water damage. In 2017, the Sowers’ family presented the mural to Missouri University of Science and Technology. Not without difficulties, the mural was transferred to the second floor of the Curtis Laws Wilson Library, where it can now be admired by all. For several long painstaking weeks, Dan Woodward, artist and conservator, accurately restored the mural to its original splendor – it was publicly rededicated on 4 October 2018.

In this seminar, Dan Woodward will interpret the mural, and describe the various steps involved in its difficult restoration including the unique problems encountered with the use of water, milk, and egg-based paints and their chemical proclivities.

Solid-state NMR Derived Structure: Applications to Boron-carbide Materials

Nathan Oyler, Dept. of Chem., UMKC

Abstract: Basic concepts in solid-state NMR, including magic angle sample spinning, are introduced for the purpose of discussing dipolar recoupling techniques for measuring constraints in the internal structure new materials.  These techniques will be applied to the elucidation of the local physical structure in a side product of the plasma-enhanced chemical vapor deposition of thin-film amorphous hydrogenated boron carbide from orthocarborane. Experimental 1H, 13C, and 11B chemical shifts and dipolar recoupling methods are used in conjunction with ab initio calculations of model  molecular compounds to assign chemical environments and determine atomic connectivities. The results of these studies and a discussion of various complicating factors will be presented.

Electrode Materials for Li/Na-ion Batteries: Improving Electochemical Performance Through Carbon Addition During Synthesis

Abdelfattah Mahmoud, GREENMat, CESAM Research Unit, Institute of Chemistry, University of Liège

Abstract: Lithium-ion batteries (LIBs) have outperformed other rechargeable battery systems since 1980 and advances in LIBs technology have improved living conditions around the globe. However, Li-ion batteries face many challenges and limitations. Na-ion batteries are considered to be an alternative to Li-ion batteries owing to the natural abundance of sodium. New electrode materials are required to increase the energy density of Li/Na-ion batteries. However, their electronic conductivity usually has to be improved through the preparation of composite powders ensuring intimate contact between the active material and conductive carbon. In this presentation, we report on the one-step synthesis of composite materials using spray-drying or hydrothermal synthesis routes, two techniques which are easily up-scalable[1-6].

In order to evidence the effect of the carbon on the microstructural and electrochemical properties of the prepared materials by a spray-drying [1-3] or hydrothermal methods [4-6]. The crystal and local structures were analyzed by combining XRD and 57Fe Mössbauer spectroscopy. The morphological properties were characterized by SEM and TEM (Figure 1). The carbon content was determined by TG/TDA and carbon analyzer. The electrochemical properties were studied by impedance spectroscopy and galvanostatic cycling in lithium and sodium cells. The reaction mechanism during cycling was investigated by combining operando X-ray diffraction and 57Fe Mössbauer spectroscopy.

Thermal Transport from First Principles: Theory and Applications

A. Chernatynskiy, Dept. of Physics, MS&T

Abstract: Recent advancements in the computational power and methodologies now permit calculations of the thermal transport properties of materials ab initio. In this presentation we will overview the technique based on the Boltzmann Transport Equation coupled with the perturbation theory at the level of cubic anharmonicity for these calculations and present applications in various areas illustrating the power of the method. Firstly, we will present calculations of the thermal transport in the sequence of the technologically important compounds Mg2X, where X= C, Si, Ge, Sn, and Pb. The accuracy of the method will be demonstrated, as well as thorough insight into the thermal transport properties of these materials. Next, we will turn to the materials at the extreme environment of high pressure and temperature and discuss applicability of the methodology in these conditions on the example of the MgxFe1-xO, an important material in the Earth’s mantle. Finally, we will turn to the calculations of the individual phonon lifetimes and present comparison with the experimental data where available. 

Quantum Chemical Computations Analysis of Biodiesel Pyrolysis for Production of Transportation Fuels and Fine Chemicals

Matthew R. Siebert, Dept. of Chem., Missouri State University

 

Exploring Chalcogenides for Highly Efficient Water Oxidation Electrocatalysts

Umanga de Silva, Dept. of Chemistry, MS&T 

Abstract: The development of a highly active catalyst for water splitting to produce oxygen and hydrogen fuel is in rising demand to fulfill the increasing human need for clean and renewable energy. However, the most crucial step for efficient electrocatalytic water splitting is the oxygen evolution reaction (OER) that takes place at the anode. Traditionally, metal oxides have been introduced for this purpose however, recent developments have shown that transition metal chalcogenides also show better catalytic activity towards OER surpassing most of the conventional oxide electrocatalysts. Herein we present how the family of chalcogenide electrocatalysts can be extended to transition metal selenides and tellurides and present a comprehensive study pf the effect of anion electronegativity on the OER catalytic properties. We will also present the investigation of composition of the active surface obtained through detailed surface analytical techniques as well as electrochemical characterizations. Nickel selenides and tellurides were synthesized by hydrothermal reactions as well as electrodeposition technique, and these catalysts exhibited lower overpotential at 10 mA/cm 2  for OER electrocatalytic activity in 1 M KOH, than conventional state-of-the-art precious metal electrocatalysts. In addition, we will present findings concerning the composition of the active surface, that answers the perpetual question, whether the catalytic surface is pre-oxidized to an oxide layer which shows further catalytic activity, or does it retain it chalcogenide composition which inherently shows better catalytic activity. We will present the synthesis, characterization and electrochemical investigations of this new catalyst and additionally, we will also discuss the stability of this catalyst during long-term OER conditions.

 

Spring Semester 2018

Rhenium Silicides: Tailoring the Structures and Properties

Fei Wang, Dept. of Chem., Missouri State University

Abstract:  Rhenium silicide, ReSi1.75, is of interest due to its complex crystal structure and potential application as a thermoelectric material. Its crystal structure is closely related to molybdenum silicide, MoSi2. The off-stoichiometry, i.e. 1.75 instead of 2 for Si, is due to Si vacancies. These vacancies are orderly distributed in the crystal structure. By doping ReSi1.75 with a third element, e.g. Al, we can tune the amount and also the arrangement of the vacancies, giving rise to an incommensurate crystal structure, which has to be expressed in a 4-dimensional superspace. Meanwhile, physical property measurements reveal that the doping also tunes the thermoelectric properties of ReSi1.75, improving its isotropic ZT value. In this talk, I will present the crystal structures of ReSi1.75 and its doped variants, rationalize the adjustability of the crystal structure with first-principle calculations, and discuss the relationship between structure and improved thermoelectric properties.

Harmful Algae, Algae Toxin, Taste, Odor Contorl, and Mitigation in Public Water Systems

Haiting Zhang, Dept. of Chem., MS&T

 

Water-Rock Interactions in Alluvial Aquifer Systems

David Borrok, Dept. of Geosciences & Geological & Petroleum Engineering , MS&T

Abstract: Shallow, geologically-young (alluvial) aquifer systems are critical sources of freshwater for irrigation, drinking, and industry in the U.S. and globally.  Many of these aquifers are under pressure from increasing demand and from natural and anthropogenic sources of contaminants such as arsenic (As). The inorganic chemistry of groundwater can be used as a powerful tool to help elucidate reaction pathways, areas of surface water recharge, mixing of fluids, and the cycling of contaminants.  This talk will examine case studies of the use of inorganic geochemistry to characterize two alluvial aquifers in Louisiana; (1) The coastal Chicot aquifer system, and (2) The Lower Mississippi River Alluvial aquifer system.  In both studies we collected data on pH, T, salinity and bulk geochemical parameters (concentrations of major and some trace cations and anions) from 20 to 25 wells in each aquifer system. These data were supplemented with the analysis of O and H isotopes.  Using the geochemical data we were able to identify zones of recharge, including rainfall and infiltration from rivers.  Relationships between Na and Cl concentrations were key to identifying areas in the aquifers influenced by salt water intrusion or mixing with brines.  We also identified important water-rock reaction pathways resulting in “excess Na” or water in which the Na cation is in excess of the Cl anion and is counterbalanced by bicarbonate.  In the Lower Mississippi River Alluvial Aquifer this reaction pathway appears to be driven by dissimilatory Fe reduction, which is further linked to the cycling of arsenic in the aquifer.  The results from this work demonstrate the utility of geochemical analyses to better understand the dynamics of alluvial aquifer systems and how, why, and where we are likely to have problems with arsenic contamination. 

 

Soft Chemical Route to Polyanion-based Cathode Materials for Alkali-ion Batteries

Prashanth Sandineni, Dept. of Chem., MS&T

Abstract: Efforts are underway to synthesize low-cost, efficient and environmentally benign cathode materials for Li- and Na-ion batteries. Polyanion-based compounds of transition metals have been actively investigated as cathode materials for Li-ion batteries since the discovery of electrochemical activity in LiFePO4. The polyanions, especially phosphates, sulfates, silicates and borates are capable of forming a wide variety of 2-dimensional (2D) and 3-dimensional (3D) structures with transition metals, which are stable and amenable for facile electrochemical Li-ion insertion. There are several other advantages of polyanion based materials over simple oxides. The electronegativity of the central atom of the polyanion due to its inductive effect increases the potential of the transition metal redox couple Mn+ /M(n-1)+ with respect to Li+ /Li compared to pure oxides. Secondly, the polyanion-based cathodes are inherently safer due to the strong covalent bond between the central atom (P, Si, S, and B) and the oxygen, which prevents them from dissociation when the cell is fully charged or fully delithiated.

The presentation will include the syntheses, structure determination and the electrochemical properties of Jarosite and new iron phosphate phases. Jarosite is the mineral name of the compounds with general formula AFe3(SO4)2(OH)6 (A = NH4, Na, K, H3O). Sodium and ammonium Jarosites were synthesized employing hydrothermal routes and partial fluorine substitution has been achieved through a solution mediated route. New iron phosphate phases include synthesis of NaFe(HPO4)2 and its subsequent conversion to Li3Fe(PO4)2 through an intermediate phase, Li2Fe(HPO4)(PO4). Both solution and mild condition solid-state ion-exchange routes have been employed to obtain the lithiated phases and their structures have been solved from high-resolution synchrotron powder X-ray diffraction data. Detailed electrochemical investigation of these phases will be discussed with respect to Li- and Na-ion insertions.

 

Are there Martians in Australia? How Acid Saline Lakes Can Serve as a Mars Analog

Melanie Mormile, Dept. of Biological Sciences, MS&T

Abstract: For as long as there have been telescopes, people have long wondered if there is life on Mars.  With the confirmation of the presence of water on Mars, this question can be seriously considered.  The acidic saline lakes of Australia can serve as analogs for previous bodies of water on Mars due to similar geochemical features. The microbial communities in these extreme sites can provide targets for the investigation of the possible presence of life on Mars.

Surface-functionalized Mesoporous Carbons for Electrochemical and Hydrogen Storage Applications

Eric Majzoub, Dept. of Physics, UMSL

Abstract: Energy storage materials for transportation applications and consumer electronic devices require (1) high energy density, (2) fast kinetics, and (3) reversibility. It is also desirable that they be environmentally friendly and inherently safe. For electrochemical applications, high surface area materials with both an electric double layer and a faradaic response are currently receiving attention for pseudo- and super-capacitors. For hydrogen storage applications, confinement of "complex hydrides" into nanoporous scaffolds is a powerful method to control the chemistry of the decomposition and rehydriding reactions; even thermodynamics may be modified by through the hydride/surface interactions. Our group synthesizes and investigates high surface area carbon materials with highly ordered nanoscale morphologies for these energy-related applications. Amorphous hard carbons with nanoscale morphology are easily prepared using a variety of self assembly methods or nanocasting. These carbon scaffolds may be functionalized through the addition of heteroatoms during the synthesis or with the introduction of functional groups afterwards. We will present results for two different projects in our group. The first focusing on carbon scaffolds for lithium-ion applications and the second for hydrogen storage applications. Nanoporous amorphous carbons have a Li-ion capacity in excess of 800 mAh/g, far in excess of the capacity of the LiC6 formed in graphite anodes, suggesting that it may be possible to plate metallic Li directly into the pore structure of the carbons and mitigate the dendrite problem that precludes the use of metallic lithium itself. Finally, for hydrogen storage applications we will show results for the infiltration of alane (AlH3) in the form of dimethylethylamine (DMEAA) into a functionalized scaffold where Lewis-acid/base interactions with the surface stabilize the alane. Time permitting we will discuss the effects of nanoconfinement on other complex hydrides.

K-index: a Quantitative Predictive Tool that Describes Complex Soft-matter Nanomorphology and Correlates it with Synthetic Conditions

Tahereh Taghvaee Yazdeli, Dept. of Chem., MS&T

 

Combinatorial Synthesis of High-efficiency Transition Metal Selenides as Oxygen Evolution Electorcatalysts 

Xi Cao, Dept. of Chem., MS&T

 Abstract: Water electrolysis has become a crucial part of sustainable, clean energy generation and it has become very imperative to discover highly active electrocatalysts composed of earth-abundant materials for the oxygen evolution reaction (OER), the most challenging half-cell reaction for water electrolysis. Combinatorial method has been reported to provide an efficient way to screen and discover material composition for promising OER electrocatalysis. Here, we have investigated a series of binary and ternary mixed metal selenides containing varying compositions of nickel, iron/copper, and cobalt as potential OER electrocatalysts. Specifically, ternary phase diagrams of Ni-Co-Fe and Ni-Co-Cu systems were explored through combinatorial electrodeposition and their OER electrocatalytic activity was measured in order to systematically investigate the trend of catalytic activity as a function of catalyst composition. In our investigation, we have synthesized series of transition metal selenide films containing mixed metal compositions such as (NixFeyCoz)3Se4 and (NixCuyCoz)3Se2 utilizing electrodeposition technique on different conducting substrates including Au-coated glass and glassy carbon (GC). Accordingly, the quaternary composition(s) exhibiting the best catalytic efficiency for the quaternary Fe-Co-Ni selenide was identified. It was observed that the quaternary selenide outperformed the binary as well the ternary metal selenides in this phase space. The structure, morphology, and composition of these new electrocatalysts were characterized by power X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and Energy dispersive analysis (EDS). The catalytic activities were studied through electrochemical measurements in alkaline media using the linear sweep voltammetry (LSV) and cyclic voltammetry (CV), while the stability of the catalyst was probed by chromoamperometric studies at a constant potential. 

Photoelectochemistry of Nanostructure/Ultrathin Electrodeposited Metals on n-Silicon 

Qingzhi Chen, Dept. of Chem., MS&T

 Abstract: The photoelectrochemical conversion of solar energy into fuels or electricity requires a semiconductor to absorb light and generate electron-hole pairs, and a catalyst to enhance the kinetics of electron transfer between the semiconductor and solution. In photoelectrochemical cells containing reactive semiconductors such as Si, the catalyst can also serve to protect the semiconductor from passivation caused by the formation of a thick SiOx interfacial layer. Herein, we explore the use of electrochemically deposited Co nanowire(NW)s and ultrathin Au on n-Si to serve as the protection layer and the catalyst for aqueous photoelectrochemical reactions. In the case of Co NWs, the oxygen evolution reaction (OER) was studied. And the Au deposited on Si was used as a catalyst for Fe2+/3+ redox reaction in a regenerative photoelectrochemical cell. The band-bending, in other words, the barrier heights were measured and found to be determined by the Si-metal junction. Furthermore, the coverage of Au on Si was also found to have an effect on the photovoltage of the cell: There was a decrease in the barrier height from 0.81 to 0.73 eV as the gold coverage was increased from island growth with 10% coverage to a dense Au film with a thickness of 11 nm. We also proved that there is a trade-off between the cell efficiency and the stability, which happens commonly among photoanode materials.

From Food Pathogen to Cancer Immunotherapy: An Update on Research Advances in LIsteria Monocytogenes 

Chen Chen, Dept. of Plant & Microbial Biology, University of California- Berkeley

 Abstract: Listeria monocytogenes is a Gram-positive food-borne facultative intracellular bacterial pathogen that can cause serious foodborne infections in immunocompromised individuals and pregnant women. L. monocytogenes has been extensively studied as a model intracellular pathogen, which led to several important fundamental discoveries in pathogenesis, and has been developed as a vaccine vector for the delivery of therapeutic cancer vaccines. Using bacterial genetic, synthetic chemical probe, and basic cell biological tools, my previous studies had advanced the understanding of the superior immunogenicity of L. monocytogenes and proposed a new strategy for the future L. monocytogenes-based cancer immunotherapy.

Applications of Transition Metal Chalcogenides in Glucose Sensins, Supercapacitors, and Overall Water Splitting

Bahareh Golrokhamin, Dept. of Chem., MS&T

 

Prebiotic Astrochemistry in the THz Gap

Susanna Widicus-Weaver, Dept. of Chem., Emory University

Abstract: Small reactive organic molecules are key intermediates in interstellar chemistry, leading to the formation of biologically-relevant species as stars and planets form.   These molecules are identified in space via their pure rotational spectral fingerprints in the far-IR or terahertz (THz) regime.  Despite their fundamental roles in the formation of life, many of these molecules have not been spectroscopically characterized in the laboratory, and therefore cannot be studied via observational astronomy.  The reason for this lack of fundamental laboratory information is the challenge of spectroscopy in the THz regime combined with the challenge of studying unstable molecules.  Ions, radicals, and small reactive organics tend to be produced in trace quantities, often at high energies, and therefore have weak laboratory spectra. In addition, THz spectrometers have historically lagged behind those in other wavelength regimes because of a lack of sources and detectors that provide the power and sensitivity needed for such studies. The laboratory astrochemistry portion of my research program combines innovative spectroscopic approaches that seek to increase spectral sensitivity in the THz regime with novel chemical production mechanisms for species of astrochemical interest.  Our laboratory work involves characterization of astrophysically-relevant unstable species, including small radicals that are the products of photolysis reactions, organic ions formed via plasma discharges, and small reactive organics that form via O(1D) insertion reactions.  In this seminar, I will present recent results from our laboratory studies, and discuss these results in the broader context of my integrative research program that encompasses laboratory spectroscopy, observational astronomy, and astrochemical modeling.

 

 

Fall Semester 2017

General Laboratory Safety Training: Safety

Environmental Health and Safety, MS&T

Abstract: 

  • General Safety
    • Environmental Health and Safety Department
    • General Rules/Policies and Prudent Practices
    • Fire Safety
    • Emergency Response
    • Hazard Communication
    • Engineering/Administrative Controls, and Personal Protective Equipment
    • Injury / Incident Reporting
  • Hazardous Material Safety and Management
    • Chemical/Biological/Radiological Hazards
    • Compressed Gas Cylinders / Cryogenics
    • Physical Hazards
    • Chemtrack Inventory System

General Laboratory Safety Training: Environmental Compliance

Environmental Health and Safety, MS&T

Abstract: 

  • Environmental Management System
    • ISO 14001
    • Corrective action
  • Hazardous Waste Management
    • Federal Regulations
    • Chemical Waste – proper storage and labeling
    • Chemical Waste – pick-up request
    • Biological Waste
    • Universal Waste
    • Spill Response

Geochemistry and the Exploration for New Metal Deposits

Marek Locmelis, Dept. of Geosciences & Geological & Petroleum Engineering, MS&T

Abstract: Magmatic sulfide ore deposits are an important source of metals such as nickel, copper and platinum-group elements. However, a decline in new world-class ore deposit discoveries in recent years suggests that most of the easily recognizable deposits have already been found. As a consequence, there is a high demand for innovative approaches that may guide future exploration efforts. 

This presentation will provide an introduction to the development of geochemical exploration tools and discuss the active research in this field in the Department of Geosciences and Geological and Petroleum Engineering at Missouri S&T. A particular focus will be on the use of mineral trace element chemistry in the exploration for magmatic nickel sulfide deposits.

Exploration techniques based on mineral chemistry have an advantage over traditional bulk-rock methods as ore-forming signatures recorded in alteration-/weathering resistant minerals are harder to erase than in bulk-rocks. In the past, exploration approaches using trace element variation patterns in minerals have often been neglected in the search for magmatic metal sulfide deposits due to analytical limitations. However, modern laser ablation ICP-MS techniques have lowered the detection limits for many trace elements as much as an order of magnitude. This presentation will discuss how an entirely new generation of mineral-based geochemical exploration tools is currently being developed using laser ablation ICP-MS.

Atomic Motion Under the Microscope- Controlling and Analyzing Few-body Dynamics

Daniel Fischer, Dept. of Physics, MS&T

Abstract: Understanding the dynamics in systems of several interacting particles is one of the key challenges of physics. Such systems generally cannot be described in closed analytical form as soon as more than two particles are involved. This dilemma is well-known as the "few-body problem" which sets us close limits to accurately predicting a many-particle system's state. Therefore, the advancement of our knowledge of phenomena that emerge due to the complex interplay of several particles requires the joined theoretical and experimental exploration for a wide range of situations. The fragmentation of atoms due to the interaction with charged projectiles, with photon, or with strong external fields represent an ideal test ground of few-body physics for several reasons: First, few-body effects in these systems are ubiquitous and relevant to many research fields and numerous technical applications, particularly in areas such 

as materials science, quantum chemistry, biological science, and information processing. Second, advanced experimental techniques are available which allow manipulation of the parameters of the few-particle quantum state with a high degree of control and accuracy. Moreover, modern spectrometers enable snapshots to be taken of the state's change over time, allowing details of the state's dynamics to be analyzed.

     At MS&T, there is an experiment in preparation that combines the most advanced experimental methods for the control and analysis of atomic few-body systems in a single apparatus: Using laser cooling and manipulation techniques, a large variety of initial states are created, ranging from single excited or polarized lithium atoms to large ensembles of atoms that are cooled down to micro-Kelvin temperatures and even to quantum-degeneracy. For the analysis, a "reaction microscope" will is employed allowing the coincident measurements of the momentum vectors of atomic fragments after ionization of the atoms. In essence, there are three fundamental questions to be addressed in the experiments: First, how do the ionization dynamics depend on the relative orientation (or helicity) of an ionizing laser field and a polarized target atom? Such experiments will help to understand fundamental symmetries and ultimately control the interaction of laser fields with chiral (atomic or molecular) targets, which play a crucial role e.g. in biochemistry. Second, how is the disintegration of an atom due to the interaction with an ionizing field influenced by its environment? This is experimentally only studied for clusters or solid targets, but largely unexplored for more dilute systems. Apart from the fundamental importance of this question, the dependence of the ionization dynamics on the environment is relevant to the understanding of the damage of biological tissue due to radiation. Finally, how does the correlated wave function of a few-particle system change as a function of the particle number and interaction type and strength? The possibility to "engineer" simple few-body systems and observe such systems comprehensively would allow one to "simulate" and understand fundamental quantum phenomena that occur in natural or artificial material.

Role of Mössbauer Spectroscopy and X-ray Diffraction in the Study of Prussian Blue Pigment Fading

Gary J. Long, Dept. of Chem., MS&T

Abstract: The two Prussian blue compounds, the so-called “soluble” KFeIII[FeII(CN)6xH2O and “insoluble” FeIII4[FeII(CN)6]3·xH2O have long been important in understanding the intervalent charge transfer transitions observed in mixed valence compounds. This transition is responsible for the intense blue colour of the Prussian blue pigments often used by artists from shortly after their discovery in 1704 to well into the early twentieth century. Unfortunately, these pigments often fade with time when exposed to light. Our long-term goal has been to obtain a better understanding of this fading of “ancient” Prussian blue pigments. Although there is an extensive literature dealing with Prussian blues, it was soon apparent that there was vast variations in the Mössbauer-spectral properties reported for often unspecified or poorly characterized compounds or pigments. Thus in reaching our goal it soon became apparent that we needed a far better understanding of the properties of modern Prussian blues and their associated pigments.

My talk will illustrate how we have obtained an improved understanding of the modern Prussian blue properties through a variety of experimental studies [1-6] and will concentrate on our Rietveld, pair-distribution, and Williamson-Hall strain analyses of high-resolution powder x-ray diffraction patterns of well characterized Prussian blues in order to explain why such a wide variation in their Mössbauer spectra is found in the literature. More specifically, our work has shown that the strain induced in Prussian blues through their extremely rapid precipitation from solution can account, at least in part, for the wide variation in their observed Mössbauer spectra.

Cancer Biomarker Discovery Using Urinary Metabolomics and Advanced Analytical Techniques:

Achievement and New Challenges

Yinfa, Center for Biomedical Reserach, Dept. of Chem., MS&T

Abstract: Metabolomics has emerged as a transformative approach to cancer bio-marker discovery owing to the intimate connection between oncogenic transformation and cellular metabolism. Heightened focus on developing molecular biomarkers that may be screened using minimally invasive point-of-care assays has prompted serious efforts into the application of urinary metabolomics for early cancer detection. Current research efforts have identified a multitude of putative metabolic biomarkers with limited clinical performance which has been attributed to challenges in urine normalization, natural metabolic variations, and poor disease specificity. Our research team has proposed the novel application of multi-marker panels that combine molecular biomarkers with clinically relevant patient information to improve biomarker performance. The biomarker panels, techniques, clinical results, and challenges, will be presented at the seminar.

 

Drug the Undruggable: from Nature to Precision Cancer Medicine

Liang Xu, Dept. of Molecular Biosciences & Dept. of Radiation Oncolory, University of Kansas

Abstract: The RNA-binding proteins (RBPs) Musashi-1 (Msi1) and Hu antigen R (HuR) are emerging therapeutic targets for cancer and cancer stem cells. So far there is limited success on small molecules that directly inhibit Msi1 and HuR. RBPs such as Msi1 and HuR are considered "undruggable" due to the lack of a well-defined binding pocket for target RNA. Since relocation to the University of Kansas in 2010, I established a multidisciplinary cancer drug discovery team to "drug the undruggable" Msi1 and HuR. Through a contemporary, structure-based, multidisciplinary and integrated drug discovery approach, we identified promising hits and initial lead compounds with sub-microM Ki values. With two funded NCI R01 grants and one DOD grant, we are employing structure-based rational design for lead optimization and target validation to discover novel compounds that inhibit the so far undruggable Msi1 and HuR, aiming to develop it as an entirely new class of molecular-targeted anti-cancer drugs.

 

 

Microwave Spectroscopic Models for Hydrogen Storage in Metal Organic Frameworks

Stewart E. Novick with Daniel A. Obenchain, G.S. Grubbs II, and Herbert M. Pickett

Departments of Chemistry Wesleyan University Middletwon, Conneticut, and MS&T

Abstract: The microwave spectra of molecular hydrogen bound to metal halides, including H2 CuF, H2 AgCl, HD AgCl, D2 AgCl, H2 AuCl, and H2 CuCl, have been studied using Cavity Fourier transform microwave (FTMW) spectroscopy. The complexes are T-shaped with the H-H as the cross of the T with the metal atom closest to the hydrogen. The molecular hydrogen is bound to the metal strongly enough such that the properties (bond lengths and electronic environments) of the binding partners are perturbed from their monomeric values, but not so strongly that the H-H bond breaks to form dihydrides with the metal. We suggest that H2 binds in this way to metal centers in metal organic frameworks (MOFs), which can be utilized to store hydrogen gas.

 

Epitaxial Lift-off of Electrodeposited Single-Crystal Gold Foils for Flexible Electronics

Jay A. Switzer, Dept. of Chem. & Graduate Center for Materials Research, MS&T

Abstract: Single-crystal silicon is the industry standard for electronic devices because of its high crystalline order and abundance. However, the brittle nature of bulk silicon precludes its use in flexible electronics. I will discuss a simple and inexpensive procedure for epitaxial lift-off of wafer-size flexible and transparent foils of single-crystal Au using Si(111) as a template. Lateral electrochemical undergrowth of a sacrificial SiOx layer was achieved by photoelectrochemically oxidizing n-Si(111) under light irradiation. Cu2O as an inorganic semiconductor was epitaxially electrodeposited onto the Au foils, which showed a more ideal diode quality factor of 1.6 (where n=1 is ideal) than the value of 3.1 observed for a polycrystalline deposit. ZnO nanowires electrodeposited epitaxially on a Au foil showed flexibility with the nanowires intact up to 500 bending cycles. A 28 nm Au foil with a sheet resistance of 7 Ω.sq-1 showed only a 4% increase in resistance after 4000 bending cycles. A flexible organic light-emitting diode based on tris(bipyridyl)ruthenium(II) was spin-coated on a foil to exploit the transmittance and flexibility of the gold foil. The simple epitaxial lift-off procedure produces single-crystal Au foils that offer the order of traditional semiconductors such as Si wafers without the constraint of a rigid substrate.

 

The Influence of the Contamination Found in Mine Tailings on Plant Growth

Joel G. Burken, Dept. of Civil, Architectural and Environmental Engineering , MS&T

 

pH Measurements Using Fluorine-19 NMR Spectroscopy

Ming Huan, Dept. of Chem., MS&T

Abstract: The pH of an NMR sample can be measured directly by NMR experiments of signal intensities, chemical shift, or relaxation time constants that depend on the pH. In the work presented here, an NMR technique was utilized based on 19F chemical shifts. For example, the chemical shift of the anion F in aqueous NaF or KF solutions changes throughout the range of pH 1 to 14 but most pronounced in the acidic range between pH  =1 and 5. Adding F- as a micro-sensor compound to solutions in NMR tubes makes it possible to accurately determine pH value in situ from 19F chemical shifts. Because pH micro-sensor compounds added to an aqueous solution have an influence on the pH, only a minimum amount of an NMR micro-sensor compound should be added to the sample. A minimum number of 4 × 1016 nuclei was found to be sufficient for NMR signal observation using a 400-MHz spectrometer. Temperature-dependent NMR experiments were conducted to establish calibration curves through which the influence of temperature on the chemical shift can be corrected. The 19F signal of external reference solution (trifluoroacetic acid) was found to have the least temperature-dependent chemical-shift variation and is suggested as independent standard for temperature-correction curves.

 

Analysis of Nanoparticle Cytotoxicity in Yeast Cells Using SC-ICPMS

Lindsey K. Rasmussen, Dept. of Chem., MS&T

 

Harmful Algal Blooms: Symptoms of Ecological Imbalance & Ecosystem Integration

Dr. Keith Loftin, Organic Geochmistry Research Laboratory & U.S. Geological Survey, Lawrence, KS

Abstract: Cyanobacterial harmful algal blooms (CyanoHABs), currently (2017) appear be the dominant type of HABs in inland waters of the U.S.  In addition to causing ecological impairment and aesthetic issues, cyanoHABs can also produce a range of toxins with a range of symptoms including dermatitis, gastroenteritis, respiratory system depression, and even death in extreme cases of exposed animals and humans.  Research published over the last decade has demonstrated that cyanotoxins and cyanoHABs are found across the country in every surface water type including lakes, reservoirs, rivers and streams, wetlands, and coastal waters at concentrations of human and ecological health concern.   An U.S. Federal and State agency collaboration called CyAN (Cyanobacteria Assessment Network) is developing a national HAB database and satellite network attempting to provide early warnings of HAB events in lakes and reservoirs across the U.S.  One objective of the CyAN project is to provide a systematic, nationwide capability to evaluate HAB frequency, distribution, and magnitude over appropriate time scales for adaptive management.  Most environmental issues are managed from a dissolved-phase contaminant standpoint which is publically invisible and resource intensive. HAB proliferation is a result of many adverse environmental issues we currently attempt to manage separately.  Visible adverse outcomes such as HABs that are also scientifically measurable 

 

Spring Semester 2017

Ring Fusion Aromatization: A Key Step Toward Pyrolytic Carbonization of Phenolic Resin Type of Aerogels

Hojat Majedi Far, Dept. of Chem., MS&T

Abstract:

 Part A: Synthesis and Oxidative Aromatization of Phenolic Resin Aerogels

We describe how polymer backbone oxidation can get involved in the pyrolytic carbonization of phenolic-resin aerogels. Using as our conceptual point of departure the need for oxidative stabilization (240 °C/air) during pyrolysis of polyacrylonitrile (PAN) and polybenzoxazine (PBO), we study the effect of oxidation on the polymeric backbone of four classical phenolic resins: resorcinol-formaldehyde (RF), terephthalaldehyde-phloroglucinol (TPOL), phloroglucinol-formaldehyde (FPOL), and phenol-formaldehyde (PF). Use of those resins in aerogel form is beneficial because it allows air circulation through their bulk, thus facilitating oxidation. Solid-state 13C NMR, FTIR, CHN and XPS showed that curing at 240 °C / air oxidizes the -CH or -CH2 groups and forces ring-fusion along the polymer backbone and formation of six-membered heteroaromatic systems (pyrylium cations).

Part B: Ultra-high Surface Area Carbons via Oxidative Aromatization of Phenolic-Resins: Applications as Energy Storage Materials and Adsorbents

We discovered that by introducing oxidative ring-fusion aromatization (240 °C/air) along pyrolysis of phenolic-resin aerogels (RF, TPOL, FPOL, and PF) we increased the surface areas of the resulting carbon aerogels substantially. For comparison, phenolic aerogels were also carbonized at 800 oC/Ar without prior oxidation at 240 oC/air and the resulting carbons were analyzed in terms of their chemical composition and their nano- and microscopic structures. Spectroscopic results (13C NMR, FTIR, XPS) and CHN analysis showed that irrespective of the pyrolytic route (i.e., with or without oxidation), all phenolic-resin-derived carbons chemically converged. However, 240 oC/air–treated carbons exhibited higher surface areas and microporosity when compared to non-treated carbons. For example, the surface area of 240 oC/air–threated carbons could be as high as 792 m2 g-1, versus 678 m2 g-1 of untreated carbons. These findings are attributed to the early rigidity imposed on the polymeric backbone by the oxidative curing process. Encouraged by those findings, surface areas were further increased using reactive etching (at 1000 °C under flowing CO2). The latter process increased microporosity dramatically and yielded extremely high surface areas (up to 2521 m2 g-1, by N2 sorption). Apart from potential uses as electrodes in supercapacitors, fuel cells and batteries, those materials are explored as adsorbents for CO2 and CH4 capture and separation.

 

 

Mining Water for the Production of Spacecraft Fuels and Propellants

Leslie S. Gertsch, Rock Mechanics & Explosives Research Center, Dept. of Geological Sciences & Engineering, MS&T

Abstract: A range of materials representative of carbonaceous near-Earth asteroids have been subjected to stepwise heating in a vacuum to investigate volatiles release and capture behavior in space.  Results show that most of the mass lost during heating is predictable by well-known reactions: dehydroxylation, de-hydration, and pyrolysis.  Cryotrapping has been shown to effectively capture the volatiles produced.  These findings form a base for additional investigations, so that the trade space of potential processes for extracting volatile compounds from carbonaceous solar system bodies can be explored effectively.

Shape-Memory Polyisocyanurate Aerogels and Porous Metal Aerogels as Energetic Materials 

Suraj Donthula, Dept. of Chem., MS&T

Abstract: 

Part 1: Shape Memory Polyisocyanurate Aerogels for Deployable Panels and Biomimetic Applications

Shape memory polymers (SMPs) remember and return to an original shape when triggered by a suitable stimulus, typically a change in temperature. They are pursued as cost-effective, low-density, higher-strain-tolerant alternatives to shape memory alloys. The ultimate refinement in terms of density reduction will be accomplished with porous SMP, and in that regard shape memory polymeric aerogels (SMPAs) offer the most viable approach which is implemented with rigid trifunctional isocyanurate nodes between flexible urethane tethers based on four short oligomeric derivatives of ethylene glycol: H(OCH2CH2)nOH (1≤n≤4). Formation of self-supporting 3D networks of particles was varied with specific combinations of monomer concentration, chemical identity of the diol and composition of the solvent (CH3CN/acetone mixtures) using statistical design-of-experiments methods. SMPAs showed a robust shape memory effect (SME), the quality of which was evaluated with four figures of merit (strain fixity, strain recovery, strain recovery rate and the fill factor). The robust shape memory effect of the SMPAs of this study was demonstrated with deployable panels and bionic hands capable of mimicking coordinated muscle function.

Part 2: Explosives and Thermites with Iron(0) Aerogels Infiltrated with Perchlorates

Monolithic nanoporous iron was prepared via carbothermal reduction of interpenetrating networks of polybenzoxazine and iron oxide nanoparticles (PBO-FeOx). Excess carbon was burned off at 600 oC in air, and oxides produced from partial oxidation of the Fe(0) network were reduced back to Fe(0) with H2 at different temperatures (temp), ranging from 300 oC to 1300 oC. Fe-temp monoliths were infiltrated with perchlorates, dried exhaustively and were ignited with a flame in open air. Most experimentation was conducted with LiClO4. Depending on temp, monoliths fizzled out (≤400 oC), exploded violently (500 oC to 900 oC), or behaved as thermites (≥950 oC). The evolution from explosive to thermite behavior was rationalized with SEM, particle size determination via N2 sorption, electrical conductivity measurements and mechanical strength data under quasi-static compression.

 

HPLC Analysis of Medicated Lens Tissues 

Justin Beltz, Dept. of Chem., MS&T

 

Advanced Functional Polymer Materials: Design, Synthesis and Applications 

Kui Xu, Brewer Science Inc., Rolla, Mo

 

The Influence of Ozone on the Indoor Environment

Glenn C. Morrison, Dept. of Civil, Architectural & Environmental Engineering, MS&T

 

Radiation Safety Amplified

Steven Mell, Account Manager, Canberra Mirion Technologies

 

Optimization of Solvent Suppression, Sequences for NMR Investigations

Annalisa Pfaff, Dept. of Chem., MS&T

 

Spectroscopy Applications in Industry: Things I Wish They had Told Me While I was in College

Dr. Stephen R. Frey, Vice President for Technology Ocean Optics Company

 

Part A: Design, Synthesis, and Reactivity Studies of Novel AGE-Inhibitors and AGE Breakers

Part B: Novel Synthetic Methods for Monofluorination and gem-Difluorination

Jatin Mehta, Dept. of Chem., MS&T

Abstract: The formation of the toxic Advanced Glycation End-Products (AGEs) as a result of the non-enzymatic reaction (Maillard reaction) between reducing sugars and amino groups in proteins, lipids, and nucleic acids is associated with diabetic complications, atherosclerosis, and Alzheimer’s disease.  Reactive 1,2-dicarbonyl compounds are important intermediates of the Maillard reaction as they would lead to the formation of AGEs. Dehydroascorbic acid (DHAA), oxidized form of ascorbic acid (ASA), is a reactive 1,2-dicarbonyl compound that rapidly reacts with lens a?crystallin and other long-lived proteins to form cross-linked aggregates that would eventually result in the cataract formation. Toward the goal of developing effective therapeutics, we have now synthesized the thiazolium and imidazolium-based novel AGE-inhibitors and AGE-breakers that would reverse the protein-crosslinking, and studied their reactivity towards the AGE-precursor DHAA, using 13CNMR spectroscopy. In this presentation, we demonstrate for the first time that these AGE-inhibitors trap DHAA in vitro to form their corresponding adducts. Further studies are in progress for their in vivo effects.

Organofluorine compounds have important role as pharmaceuticals, agrochemicals, and in materials science due to their properties of enhanced lipophilicity and thereby bioavailability. Recent trend in the area of fluorination is toward developing 18F-based positron-emission tomography (PET) agents for diagnostic imaging. We have developed convenient synthetic methods based on the Photoredox chemistry and the readily available fluorine-containing precursors, such as Selectfluor. In this presentation, we will outline our progress in this area of monofluorination and difluorination of organic compounds, and novel photoredox-catalyzed gem-difluorination of 1,3-dithiolanes.

 

Low-Coordination Numbers, Unusual Bonding, and Dispersion Force Effects in Molecules

Philip P. Power, Dept. of Chem., University of California, Davis

Abstract: The theme of the lecture concerns the often subtle effects of London dispersion forces on the stability and structures of compound classes as diverse as two-coordinate transition metal complexes (including quintuply-bonded species), high valent transition metal alkyls, multiple bonded main group compounds, persistent main group radicals, and the Lewis acid/base properties of boranes. The main conclusion is that the consideration of dispersion forces is necessary in discussions of the structure and reactivity of all compounds substituted by bulky organic groups. The increased understanding of such forces should allow their effects to be deliberately used to enhance stability and allow access to hitherto unknown types of compounds.

Seminar Archives : 2007-2016

Spring 2023

Intellectual Property and Entrepreneurship

John E. Woodson, Interim Director of Technology Transfer & Economic Development, Office of Technology Transfer & Economic Development

Abstract: Whether you work for someone else or work for yourself, you should have a basic understanding of the different types of intellectual property and what it takes to insure they retain their value. Corporations and entrepreneurs both need and use intellectual property to create value for the enterprise. This talk will cover the patent process, patents, trademarks, and trade secrets, and it will also cover main considerations for seriously considering entrepreneurship. In order to have any chance to make it as an entrepreneur, you need more than a product, most importantly, you need a customer and a plan.

Quantum computing, quantum teleportation and time crystals

Cheng Hsiao Wu, Professor of Electrical Engineering, Electrical & Computer Engineering, Missouri S&T

Abstract: Quantum computing are parallel computing and are nonlocal in nature. Geometry, physics and computing are triangularly interrelated. There exist four new fundamental nonlocal operator-state relations for an entangled atomic chain. Computation states are then cyclic. There exists a minimum entanglement distance between any two atoms of the chain. Any addition of four times of that distance provides the foundation for quantum teleportation in a piece-wise Euclidean chain. Time crystals are the direct computation results that an entangled chain is capable of computing. There are four interacting planar time crystals with the same Poincare cycle, but only half of the results are observable as we predict and thus quantum computing is “irreversible”. However, when geometry changes, there exist “spherical time crystals” from the rotational symmetry breaking. Thus, we predict “time” can be “curved” in the Fourier space, the space we observe all the parallel computation results. In long entangled chain, a small section of time crystal can be duplicated elsewhere of the chain with “birth-and-death’ capability in addition to the “perpetual motion” claimed by the Google group last July. Sierpinski triangle with self-similar features provides the foundation for the true artificial intelligence where larger scales of operator-state space-time relations emerge.

Click to view Dr. Cheng Hsiao Wu's seminar flyer

A Sinuous Search for the Solid Structure of Fe3(CO)12

Fernande Grandjean and Gary J. Long, Emeritus Professor of Physics, University of Liège, Belgium and Adjunct professor of Missouri S&T

Abstract: The search for the solid structure of Fe3(CO)12 beautifully illustrates the mechanism of scientific research, specifically the modification, adjustment, and correction of knowledge through more advanced measurements. This search will use x-ray diffraction, infrared, NMR, and Mössbauer spectral measurements to determine the now well accepted solid structure of Fe3(CO)12 and to better understand the dynamics present in the cluster.

Click to view Dr. Grandjean and Dr. Long's seminar flyer

Vibronic coupling in N-methylpyrrole

Alexander Davies, Post-doctoral fellow, Chemistry, Missouri S&T

Abstract: The 1A21A1 (S1 ← S0) electronic transition of N-methylpyrrole (NMP) is electric dipole forbidden. Therefore, one would not expect to observe any structure arising from this electronic transition; however, this is not the case and there is extensive structure, even at low internal energies (> 1100 cm-1 above the S1 origin). Herzberg-Teller coupling (more generally, vibronic coupling) is a complicated, although well-established phenomenon whereby intensity is ‘stolen’ from a nearby electronic state, to which a transition from the 1A1 electronic state is allowed — this is the key to explaining the observed structure. Assignments of the observed bands are made through a combination of resonance-enhanced multiphoton ionisation (REMPI) and zero-electron-kinetic-energy (ZEKE) spectroscopies, briefly mentioning the two-dimensional laser-induced fluorescence (2D-LIF) technique.

Many of the ZEKE spectra are consistent with the 3s Rydberg nature of the 1A2 electronic state (in the Franck Condon region) and the Herzberg-Teller coupling schemes required to prepare the intermediate; however, there is also some activity which is a little more difficult to explain. Comparisons will be drawn to meta-fluorotoluene (mFT), whose S1 ← S0 electronic transition is electric dipole allowed, as well as a brief discussion on how vibrational couplings within the S1 state, arising from anharmonicity, further add to the complexity of an already intriguing molecule.

Click to view Dr. Alexander Davies's seminar flyer

Addressing diffusion in the solid photo- and photoeletrocatalysts

Pravas Deria, Associate professor, School of Chemical & Biomolecular Science, Southern Illinois University-Carbondale

Abstract: Light-driven reactions hold promise to develop processes that can encompass solar energy conversion, organic transformation, to contamination management. To ease the transformations that are energetically challenged or otherwise not thermally allowed—like, kinetically challenged CO2 reduction, organic transformations involving C-H activation, or thermally inaccessible cycloaddition reactions—one needs to build an efficient deployable photocatalysts platform. Traditional solution-dissolved photosensitizers, exploiting their long-lived triplet state, function by providing a time window for slower diffusion and chemical time scale. However, special care must be taken even for those reactions that do not require a triplet excited state (like cycloaddition) to avoid singlet oxygen-derived side products. The primary criteria for scalable solid photocatalysts are challenging it requires efficient exciton/energy transport to the reaction sites and the ability to split the delivered exciton without the involvement of molecular (i.e., photosensitizer) diffusion. This is simply because of fixed photosensitizers where only a small portion, at the outer surface, is exposed to the light. A porous solid, such as a MOF system that allows substrates to diffuse, can only work if the molecular excitons are spatially dispersed and/or easy to displace -possibly along the direction of the major substrate diffusion channel (i.e., anisotropic exciton transfer). System design with the appropriate ground and excited-state potential will, therefore, be the next step to 
driving a redox reaction. A picosecond timescale exciton transport and sub-nanosecond timescale exciton splitting should be the primary target to develop such a platform. With such a design in hand, we will show how MOF-based photo redox chemistry works and what are other benefits of this development.

Click to view: Dr. Pravas Deria's seminar flyer 

Spatially resolved spectroscopy: Exploring systems at the nanoscale

Dr. Sabine N. Neal, Research Associate Interface Science and Catalysis group Center for Functional Nanomaterials Brookhaven National Laboratory

Abstract: Vibrational spectroscopy is a sensitive probe of complex physical phenomena in both inorganic and organic systems. The analysis of vibrational mode trends and displacement patterns allows for insight into a material’s properties including lattice distortions, phase transitions, charge ordering, and spin-lattice coupling constants, just to name a few. When coupled with external stimuli, such as temperature, pressure, or magnetic field, infrared spectroscopy can reveal the relationships between charge, structure, and magnetism. However, the ability to obtain real space information has proved to be a challenge due to the inability to focus an infrared beam tightly enough to probe nano-sized samples. This issue, however, has been circumvented with the advent ofspatially resolved infrared spectroscopy, such as O-PTIR and tipbased near-field infrared. These techniques have allowed for the comprehensive studies of nanomaterials, from single layer systems to organic high energy materials.

Dr. Sabine Neal's seminar flyer

 

Metal-Free Photoredox Catalysis for the S-Trifluoromethylation of Heteroaromatic Thiols

Raheemat Rafiu, Graduate Student, Chemistry, Missouri S&T

Abstract: The S-Trifluoromethylation of thiols provides access to pharmaceutically interesting compounds. The current synthetic methods for this trifluoromethylation reaction involve the use of either expensive noble metal-based organometallic catalysts and expensive or hazardous reagents. We have demonstrated a convenient visible-light photoredox catalyzed S-trifluoromethylation of various thiols under metal-free conditions, using the cost-effective sodium trifluoromethanesulfinate (Langlois regent) and diacetyl as the photocatalyst. This novel organocatalysis-based synthetic method provides a convenient and cost-effective alternative to the transition-metal catalyzed photoredox reactions.

Raheemat Rafiu's seminar flyer

Investigation of RNA binding by the eIF4B translation initiation factor, and dynamics studies of proteins utilizing NMR and other biophysical techniques

Dr. Somnath Mondal, Postdoctoral Research Scientist, Pennsylvania State University, USA

Abstract: Eukaryotic initiation factor 4B (eIF4B) is a multidomain protein with a range of activities that serve primarily to promote the association of messenger RNA to the 40S ribosomal subunit during the translation initiation process. Deletion and site-directed mutagenesis studies have identified a few functional domains within eIF4B, two of which are involved in RNA binding and are implicated in linking mRNA to the 40S ribosomal subunit during translation initiation. An N-terminal RNA recognition motif (RRM; residues 97-175) has been shown to bind the 18S rRNA of the 40S ribosomal subunit in the earlier report. However, it has not been completely explored except for the RRM domain from eIF4B. A second RNA binding domain is located toward the C-terminus (residues 367-423) and has been termed the basic domain (BD) since it contains two arginine-rich motifs (ARMs). This region, which has not been assigned to a particular structural family, binds RNA nonspecifically but with high affinity and has been proposed to bind mRNA during initiation. In addition, eIF4B has been reported to bind several proteins related to translation, ribosomal RNA, and mRNA, but again only in a few studies. More than three-quarters of the eIF4B protein is intrinsically disordered and tends to display phase separation, attributing the reason why eIF4B has not been explored in depth, except for the RRM domain. We have utilized NMR spectroscopy and other biophysical techniques (smFRET, ITC, CD, Fluorescence, etc.) to address RNA binding properties from different constructs from the C- and N- terminus of eIF4B and addressed the phase separation behavior from the C-terminal domain of eIF4B. In addition, I will briefly discuss studies on various protein dynamics utilizing NMR spectroscopic techniques and other biophysical methods.

Dr. Somnath Mondal's seminar flyer

Crystal Engineering of Programmable Sponges for Energy, Environmental and Health Applications

Dr. Mario Wriedt, Kodak CAMP Distinguished Professor, Department of Chemistry and Biomolecular Science, Clarkson University, NY, USA

Abstract: Metal-organic frameworks (MOFs) are crystalline porous materials composed of metal clusters or ions connected by polytopic organic linkers. Their framework structures, pore environment, and functionality make them uniquely tunable by the choice and connection of metal and organic building blocks, allowing the design of innovative materials with customized properties. Our research programs all address interrelated fundamental aspects of the design, synthesis, and characterization of functional MOF materials. This presentation is a comprehensive overview on how the synergy of crystal engineering and X-ray diffraction will pave the way for the rational design of novel advanced functional MOF materials to address our society’s most pressing energy, environmental, and health needs (e.g., carbon capture, water remediation, viral testing).

Dr. Mario Wriedt's seminar flyer

Evaluation of N-acetylcysteine Amide as a Potential treatment option for Traumatic Brain Injury using tandem LC-MS

Olajide Adetunji, Graduate Student, Chemistry, Missouri S&T

Abstract: Physical injury from sports and freak accidents are common causes of Traumatic Brain Injury (TBI). Commonly overlooked, is TBI via exposure to explosives with prevalence in military personnel and veterans. Existing diagnostics are costly, time consuming, and sometimes insensitive to milder TBI forms, influencing a need for fast and sensitive techniques for mild TBI detection by investigating potential biomarkers that may be altered due to TBI. A pathophysiological consequence of TBI is oxidative stress from reactive oxygen species proliferation after physical disruption of neurons and glial cells leading to alteration in the levels of endogenous antioxidants and their oxidized products in the brain and peripheral fluids. Antioxidant therapy using N-acetylcysteine Amide can be useful mitigators of this oxidative stress characteristic. Additionally, lipid peroxidation by-products and other important small molecule biomarkers can give invaluable information about TBI progression. In our study, rats were exposed to open-field blasts mimicking of a real-life explosion to induce TBI and evaluate antioxidant therapy. Subsequently, various biomatrices were harvested from test animals for analysis. Coupling rigorous sample clean-up with LC-MS/MS analysis, levels of potential biomarkers for TBI in the groups and sample matrices were determined in this study. The LC-MS/MS methods yielded excellent sensitivity, linearity, recovery, and reproducibility for all the investigated analytes.

Olajide Adetunji's seminar flyer

Explorations of the Synthesizability and Photoelectrochemical Properties of Metastable Semiconductors

Dr. Paul A. Maggard, Professor of Chemistry, North Carolina State University, USA

Abstract: Metastable semiconductors have been discovered in many chemical systems that have desirable properties for driving fuel-producing redox reactions from sunlight, including broad visible-light absorption, optimal band edge energies, defect tolerance, and functional carrier mobilities. These photoelectrochemical properties have frequently been found to stem from their metastable nature, e.g., specific features in their crystalline structures and/or compositions lead to being thermodynamically unstable with respect to phase segregation.  Recent results will be presented on mixed-metal oxides and carbon nitrides that demonstrate new flux-mediated syntheses and kinetic stabilization in this growing class of semiconductor systems.1-3 Their syntheses have been achieved by reactions that leverage the exothermic formation of stable salt side products as well as shortened reaction diffusion pathways and low reaction temperatures.  Kinetic stabilization of the products has also been enhanced via the application of a) high cohesive energies of an underlying substructure that is maintained during the reaction, and b) solid solution compositions which help to inhibit phase segregation while also providing for percolation pathways.  These approaches have yielded, e.g., the first known Sn(II)-perovskites that are isoelectronic to widely commercialized Pb(II)-containing piezoelectrics.  Photocatalytic properties in these systems will primarily be described for light-driven H2O and CO2 reduction as polycrystalline films and as suspended powders when in aqueous solutions under ultraviolet and visible-light irradiation.

Dr. Paul A. Maggard's seminar flyer

Accessing anionic and cationic redox in metal chalcogenides through building block approach

Santhoshkumar Sundaramoorthy, Graduate Student, Chemistry, Missouri S&T

Abstract: Boosting the energy density of Li-ion batteries is of prime importance in the current era to meet the energy demands for electric vehicles (EV’s). In this regard cathodes play an important role as the specific capacity is directly related to the number of Li-ions to be extracted from or inserted into the cathode as a function of redox. Towards achieving this goal, researchers are looking into combining both cation and anion redox in the new generation cathode materials. In this regard, we have developed building block approach of synthesis targeting specific compositions that can potentially act as candidate for cathodes and solid 
electrolytes. Through this technique we discovered two new polyanion sulfidebased cathodes with Cu+and Fe2+ cations exhibiting high reversible specific capacities. Further their charge storage mechanism and structural stability were evaluated by spectroscopic (XAS and XPS) and diffraction studies (Synchrotron XRD). Following these works we also synthesized two new ternaryselenidebased building blocks (Li5MSe4, M = Al & Ga) and measured their ionic conductivity. Aliovalent doping in these building block showed improvement in Li-ion conduction showing promises in search of potential solid electrolytes for Li-solid state batteries. At the end, an overall overview on chalcogen based materials and its optimization for energy storage devices will be summarized. 

Santhoshkumar Sundaramoorthy's seminar flyer

Harnessing the chemistry of cementitious materials towards the next-generation eco-efficient concretes

Monday Okoronkwo, Assistant professor, Chemical and Biochemical Engineering, Missouri S&T

Abstract: The production of conventional cement is an energy and CO2-intensive process contributing to over 8 % of the global anthropogenic CO2 emissions. To reduce the carbon footprint of cement and concrete, efforts are increasingly directed toward developing sustainable low-carbon alternative cementitious materials. Chemistry is at the heart of such efforts, helping us to understand what forms when cements react with water (hydration), and how they may impact the properties and performance of the resulting cement-based products. Through such understanding, the design and optimization of new alternative cements are enabled. This talk will present some of our work in understanding the hydration reactions and the development of phase assemblages and properties of some candidate low-carbon alternative cements, including blended cements, alkali-activated cements, sulfoaluminate cement, and carbonated cements.

Dr. Monday U. Okoronkwo's seminar flyer

New NLO Materials: Design, Synthesis, and Crystal Growth

Prof. P. Shiv Halasyamani, Department of Chemistry, University of Houston

Abstract: Nonlinear optical (NLO) materials are critical in generating coherent light through frequency conversion, e.g., second harmonic generation (SHG). From the ultraviolet (UV) to the infrared (IR), NLO materials have expanded the range of the electromagnetic spectrum accessible by solid-state lasers. Wavelengths where NLO materials are still needed include the UV (~200 - 400nm) and deep UV (< 200nm). Coherent deep-ultraviolet (DUV) light has a variety of technologically important uses including photolithography, atto-second pulse generation, and in advanced instrument development. Design strategies will be discussed, as well as synthetic methodologies. In addition, the crystal growth, characterization, and structure-property relationships in new UV and DUV NLO materials discovered in our laboratory will be presented. Finally, our crystal growth capabilities and recent crystal growth of functional materials will be described.

Dr. P. Shiv Halasyamani's seminar flyer

Development of Catalytic Membranes and Composites for Energy Storage Devices and Nonenzymatic Biosensors

Harish Singh, Graduate Student, Chemistry, Missouri S&T

Abstract: The continuous excessive usage of fossil fuels has resulted in its fast depletion, leading to an escalating energy crisis as well as several environmental issues leading to increased research towards sustainable energy conversion. Electrocatalysts play crucial role in the development of numerous novel energy conversion devices, including fuel cells and solar fuel generators. In particular, high-efficiency and cost-effective catalysts are required for large-scale implementation of these new devices. Over the last few years, transition metal chalcogenides have emerged as highly efficient electrocatalysts for several electrochemical energy conversion processes such as water splitting, oxygen reduction reaction and solar energy conversion. These transition metal chalcogenides exhibit high electrochemical tunability, abundant active sites, and superior electrical conductivity. Hence, they have been actively explored for various electrocatalytic activities. Herein, we have explored of transition-metal chalcogenide electrocatalysts for oxygen evolution, oxygen reduction, and illustrated structure–property correlation with the help of density functional theory (DFT). Lastly, we will discuss the electrocatalytic activity of the transition metal chalcogenides towards biomolecule conversion, enhancing their applicability as biosensors for detecting potentially life-threatening disorders. Detailed studies of the chemical reactivity, electrochemical activity, interfacial chemistry, and functional stability of the transition metal chalcogenides that make all these applications feasible will be discussed in depth.

Harish Singh's seminar flyer

Molecular Spectroscopy and Dynamics on Multiple Potential Energy Surfaces

Dr. Jinjun Liu, Department of Chemistry, University of Louisville

Abstract: Research in the University of Louisville Laser labs (UL3) (https://sites.google.com/site/uofllaserlabs/) consists of spectroscopic studies of gas-phase molecules and condensed-phase materials using state-of-the-art high-resolution and ultrafast laser systems and cutting-edge spectroscopy techniques. Our high-resolution spectroscopy studies center on the detection and characterization of open-shell molecules on multiple potential energy surfaces (PESs). Our target molecules include molecular free radicals as reactive chemical intermediates in combustion and atmospheric chemistry. The spectroscopic methods employed include laser-induced fluorescence/dispersed fluorescence (LIF/DF) spectroscopy for alkoxy (RO⸱) radicals and cavity ring-down (CRD) spectroscopy for peroxy (ROO⸱) radicals. These two techniques are also used to study metal-containing molecules, e.g., alkaline-earth monoalkoxide radicals (MORs), which have been proposed as candidates for direct laser cooling and will have important applications in quantum computing, quantum information, and fundamental physics. Recently, our group has built a mid-infrared high-resolution laser spectroscopy apparatus to support the observations of the James-Webb Space Telescope (JWST) and started developing a novel cavity-enhanced double-resonance spectroscopy technique to investigate molecular “dark states” and to decipher the complex energy level structure and intramolecular interactions. On the theoretical side, we are particularly interested in molecular species with the Jahn-Teller (JT) and pseudo-Jahn-Teller (pJT) effects, symmetry-specific vibronic (vibrational-electronic) interactions that cause spontaneous distortion of the geometry and PESs of polyatomic molecules in degenerate or nearly degenerate electronic states. Spectroscopic models and software have been developed to predict, analyze, simulate, and fit vibronic, rotational, and fine structures in high-resolution spectra of open-shell molecules. High-level quantum chemistry calculations are used to help understand the geometry, energy level structure, and dynamics of molecules on multiple PESs.

The nature and strengths of inter-state coupling can also be directly detected in time-resolved spectroscopy, a powerful tool for investigating energy and charge transfer processes. I will use the femtosecond pump-probe transient absorption study of excited-state dynamics of molecule-like ligand-passivated (CdSe)34 nanoclusters (d=1.6 nm) to demonstrate the capabilities and limitations of ultrafast spectroscopy in understanding charge carrier dynamics in nanostructures and on their interfaces, which can aid in the design of high-efficiency photovoltaic and light-emitting devices.

Jinjun Liu's seminar flyer

Reactivity of Coinage Metal Complexes Supported by Tetramethylguanidinyl Triphenyl Stibine and Bismuthine Ligands towards Nitrene Transfer Chemistry

Meenakshi Sharma, PhD Candidate, Department of Chemistry, Missouri S&T

Abstract: Carbon Nitrogen (C-N) bonds are ubiquitous in pharmaceuticals, agrochemicals, natural products, and ligands for transition metal catalysts. Transition-metal catalysts introduce new C-N bond into the desired molecules by C-H bond activation or by addition of nitrene across a C=C bond to form aziridines, which can easily be converted into an amine by various chemical transformations.

Transition-metal catalyst frameworks supported by tripodal [TMG3trphen] ligands mediate nitrene transfer from nitrogen sources such as PhI=NR (PhI=NTs or PhINTces) to a diverse group of aliphatic and aromatic hydrocarbons and olefins. These reactions are categorized as amination and aziridination reactions. Novel tripodal ligands and their complexes with coinage transition metals (Cu, Ag, Au) with different axial atoms such as CH, Sb and Bi and benzene platform have been designed to impart weaker axial ligand field, which, in turn, enhances the electrophilicity of nitrene, potentially affording more reactive and site-selective aminated products. The trinuclear copper catalysts [TMG3trphenSbCu32-Cl)3] and [TMG3trphenBiCu32-Cl)3] have shown promising results towards aziridination of styrenes with excellent yields though the reactivity of the silver catalyst [TMG3trphenSbAg32-Cl)3] needs to be explored more for comparative studies. The copper complexes are also reactive for the selective amination of various hydrocarbons at benzylic and tertiary C–H sites.

Meenakshi Sharma's seminar flyer

 

Chemistry for Environment and Health

Dr. Michael Eze, Postdoctoral Scholar, Bioinstrumentation and BioMEMS Laboratory, University of California Davis. 

Abstract: Industrialization and increasing demand for energy have led to an unabating exploitation of natural resources, especially fossil fuels. Even beneficial activities (such as pest control in agriculture) are leaving behind unwanted and toxic effects. This often results in anthropogenic contamination of aquatic and terrestrial ecosystems, which threatens the survival of our planet and species. Similarly, the experience of the recent pandemic brought to bare the havoc that infectious diseases can cause. Even more important, it has shown the need for rapid and non-invasive diagnostic tools for early detection of diseases. Sadly, most traditional diagnostic methods are both invasive and expensive. In view of the environmental and health impacts of toxic contaminants and infectious diseases, it is worth asking: can science provide the urgently needed panacea? This talk will examine the answers to this question. Specifically, it will
amine eco-friendly approaches for environmental pollutant remediation. It will also highlight how advances in (bio)analytical techniques, metabolomics andchemometrics are helping to innovate non-invasive diagnostic tools for early detection of human and plant diseases.

Dr. Michael Eze's seminar flyer

Development of Machine Learning Potentials for Multicomponent Systems

Ridwan Sakidja, Professor, Physics Astronomy and Materials Sci., Missouri State University, Springfield

Abstract: Developing the interatomic potential models for muti-component systems has been “the holy grail” in the field of computational materials science. In this talk, I will discuss the use of Machine Learning as the means to address this issue quite effectively. With the advancement of GPU resources and GPU-based neural network algorithms, we have a great opportunity nowadays to utilize ML potentials to simulate a wide range of materials phenomena and processing in various scales. Typically, the potential development starts from the database generation through electronic structure calculations within the DFT approximation at ground state as well as elevated temperatures. The subsequently extracted critical data (of energy, stress, and forces) is then fed to the neural network with various schemes of invariant/equivariant representations. The key here is the linear scalability associated with these AI-driven models which in turn enable us to develop large scale atomic-based simulations with potential technological implications. Within this context, I would like to also discuss the feasibility in constructing AI-powered Virtual Autonomous Materials Discovery (v-AMD) to help accelerate materials development.

Dr. Ridwan Sakidja's seminar flyer

A journey in electrochemistry: From single nanoparticle to in operando electrochemistry and future opportunities

Dr. César A. Ortiz-Ledón, Postdoctoral Scholar, Department of Chemistry, University of Wisconsin-Madison

Abstract: Electrochemistry is an attractive field that offers a wide range of applications. In the last decade, electrochemistry has found applications to study single entity systems, from developing ultrasensitive sensors for single molecule detection to studying electron transfer reactions at individual metal nanoparticles and extract valuable kinetic information. Besides this, several research groups have coupled electrochemistry with other fields such as spectroscopy, this combination becomes a powerful tool to probe electrochemical reactions and obtained chemical information in situ. In this seminar, first section will explain how electrochemistry is used to study electrocatalysis at single nanoparticles and nanoparticle ensembles with ultramicroelectrode dimensions. What are the advantages of these studies and potential applications to obtain kinetic information at the single nanoparticle level. Following by a section that will cover development of in operando electrochemistry to study electrode-electrolyte interfaces in Li-ion batteries. This section aims to demonstrate how combining other techniques such as gravimetry and infrared spectroscopy with electrochemistry helps to understand the origin of electrolyte degradation in Li-ion. Understanding this interface from Li-ion batteries is of high importance, as these devices are widely used for energy storage and found in multiple electronic devices such as cell phones, laptops, and electric vehicles. The third and last part of this talk will explore what are the future opportunities in electrochemistry and why electrochemical interfaces are important. In this section will bring new strategies to study these interfaces by implementing in operando electrochemistry to study nanoconfined spaces and surface reactivity of electrocatalytic materials. Concluding how electrochemistry is of huge importance to study chemical problems found in energy conversion, energy storage, and electrodeposition of metals.

Dr. Cesar Ortiz-Ledon's seminar flyer

Forging Robust Nanoscale Catalytic Interfaces for a Sustainable Future

Dr. Junrui Li, Postdoctoral research associate in the Voiland School of Chemical Engineering and Bioengineering, Washington State University

Abstract: There has been increasing interest in achieving a sustainable future with fuels, chemicals and materials obtained from renewable sources. Sustainable materials and energy production requires efficient catalytic processes. Rational design and development of robust catalysts for such processes remains a key challenge. Despite extensive efforts in this research area, new innovations in effective catalytic design at nanoscale levels are limited. This talk covers examples of how robust catalytic interface can be precisely tailored at nanoscale dimensions to achieve an improved performance in green energy power source-fuel cells and in catalytic valorization of renewable biomass derived molecules. The first section illustrates: (1) intermetallic nanostructures with ordered atomic arrangements can stabilize base metals under the aggressive condition of fuel cells; (2) hard-magnet intermetallic nanostructure interfaced with atomically thin Pt overlayers that exhibit extraordinary fuel cell performance; (3) identification of a structural descriptor to guide high-throughput screening and discovery of high-performance catalysts for fuel cells. The second and third sections detailing oxidative valorization of biomass-derived molecules outlines: (1) the discovery and investigation of a Pt-based ternary nanoscale interface that steers the favorable reaction pathway for efficient electrocatalytic utilization of biomass-derived liquid fuels; (2) interfacing Pt with Au at nanoscale dimensions to suppress the oxidation/dissolution of Pt during thermocatalytic oxidation of glucose to achieve high yields to value-added products and long-term stability.

Dr. Junrui Li's seminar flyer