Digital Commons Network^™

Trace Gas Emissions From Combustion Of Peat, Crop Residue, Domestic Biofuels, Grasses, And Other Fuels: Configuration And Fourier Transform Infrared (Ftir) Component Of The Fourth Fire Lab At Missoula Experiment (Flame-4), C. E. Stockwell, R. J. Yokelson, S. M. Kreidenweis, A. L. Robinson, P. J. Demott, R. C. Sullivan, J. Reardon, K. C. Ryan, D. W.T. Griffith, L. Stevens

Chemistry and Biochemistry Faculty Publications

During the fourth Fire Lab at Missoula Experiment (FLAME-4, October-November 2012) a large variety of regionally and globally significant biomass fuels was burned at the US Forest Service Fire Sciences Laboratory in Missoula, Montana. The particle emissions were characterized by an extensive suite of instrumentation that measured aerosol chemistry, size distribution, optical properties, and cloud-nucleating properties. The trace gas measurements included high-resolution mass spectrometry, one-and two-dimensional gas chromatography, and open-path Fourier transform infrared (OP-FTIR) spectroscopy. This paper summarizes the overall experimental design for FLAME-4-including the fuel properties, the nature of the burn simulations, and the instrumentation employed-and then focuses on …

Development Of Novel Efficient Organocatalytic Reactions For The Construction Of Complex Molecular Architectures, Aiguo Song

Chemistry and Chemical Biology ETDs

Facile construction of synthetically and medicinally significant optically active molecular architectures from simple and readily available materials via catalytic enantioselective cascade processes is the cental goal in organic synthesis. Toward this end, my Ph.D. work focuses on the development of novel organocatalytic asymmetric cascade reactions and their application in the synthesis of versatile molecular structures. A novel amine catalyzed decarboxylative enantioselective Diels—Alder reaction between aldehydes and readily available coumarin-3-carboxylic acids as dienophiles via dienamine catalysis has been realized. Notably, the decarboxylation facilitates the release of the catalyst in the Diels—Alder reaction adducts and achieves high reaction efficiency in terms of …

Criteria For Evolution Of Successful Proteins: Fold Fitness And Domain Dynamics Explored, Tyrel Bryan

Chemistry and Chemical Biology ETDs

The Haloacid Dehalogenase Superfamily (HADSF) is a ubiquitous family of enzyme with more than 32,000 members. A variety of reactions are catalyzed by HAD members, but a majority of HAD members are phosphatases. Dephosphorlyation of organophosphate metabolites are carried out in the conserved Rossmann-like core domain. The Rossman-like core domain houses the conserved active site residues necessary for catalysis and also supports domain inserts associated with substrate binding. This dissertation will focus primarily on investigating fold fitness and domain dynamics of HAD proteins more specifically three C2 capped proteins. The first part will focus on whether or not the prevailing …

Spectroscopic Studies Of Conjugated Polymer Nanostructures And Polymer/Acceptor Blends, Jian Gao

Chemistry and Chemical Biology ETDs

This dissertation presents the results of investigations into organic semiconducting systems at the nano- to mesoscales through spectroscopic and electrical imaging techniques. Particular emphasis was put on capturing the role of conformation and morphology on electronic properties and processes. The combination of experimental methods and data analysis techniques used in this work reveals useful insights into the correlations between polymer structures and their photovoltaic device performance, and provide clues to developing better performing organic solar cells. The main approach of this work is using prototypical conjugated polymer systems, either ensemble or in their nanostructures, to study the solar cell active …

Development Of Novel Small Molecules For Imaging And Drug Release, Yanting Cao

Chemistry and Chemical Biology ETDs

Small organic molecules, including small molecule based fluorescent probes, small molecule based drugs or prodrugs, and smart multifunctional fluorescent drug delivery systems play important roles in biological research, drug discovery, and clinical practices. Despite the significant progress made in these fields, the development of novel and diverse small molecules is needed to meet various demands for research and clinical applications. My Ph.D study focuses on the development of novel functional molecules for recognition, imaging and drug release. In the first part, a turn-on fluorescent probe is developed for the detection of intracellular adenosine-5'-triphosphate (ATP) levels based on multiplexing recognitions. Considering …

Stable Solar Cells Through Controlled Block Copolymer Self-Assembly And Cooperative Hydrogen Bonding Interactions, Fei Li

Chemistry and Chemical Biology ETDs

Current state-of-the-art polymer solar cells adopt the bulk-heterojunction (BHJ) morphologies where the electron donors (i.e. conjugated polymer) and electron acceptors (i.e. fullerenes) as active layers are mixed in an intimate way. The phase separation that modulates the exciton diffusion and charge transport in the current BHJ morphology is an uncontrolled process and thus results in random domain sizes of the polymer/fullerene blend. In addition, the polymer and fullerenes in the blend are intrinsically two immiscible materials and they tend to undergo macrophase separation eventually, which leads to deteriorated device performance. One way to address the abovementioned issues is to attach …

Theoretical Studies Of Transition Metal Catalysis, Ryan S. Johnson

Chemistry and Chemical Biology ETDs

Transition metal catalysis, being critical to nearly all aspects of the modern industrial world, is the focus of a series of theoretical studies which seek to elucidate the fundamental and electronic origins of enhanced chemical activity and selectivity. The application of density functional theory on extended single metal and alloyed surfaces, supported single metal atoms, and gas phase cationic species illuminate various aspects of transition metal catalysis in a wide range of enviornments. Adsorption, reactivity, and other mechanistic details developed here suggest possible mechanisms used to aid interpretation of experimental results and guide developement of future catalysts.

Identification And Quantification Of Gaseous Organic Compounds Emitted From Biomass Burning Using Two-Dimensional Gas Chromatography/Time-Of-Flight Mass Spectrometry, L. E. Hatch, W. Luo, J. F. Pankow, Robert Yokelson, C. Stockwell, K. C. Barsanti

Chemistry and Biochemistry Faculty Publications

The current understanding of secondary organic aerosol (SOA) formation within biomass burning (BB) plumes is limited by the incomplete identification and quantification of the non-methane organic compounds (NMOCs) emitted from such fires. Gaseous organic compounds were collected on sorbent cartridges during laboratory burns as part of the fourth Fire Lab at Missoula Experiment (FLAME-4), with analysis by two-dimensional gas chromatography/time-of-flight mass spectrometry (GC×GC/TOFMS). The sensitivity and resolving power of GC×GC/TOFMS allowed the acquisition of the most extensive data set of BB NMOCs to date, with measure ments for 722 positively or tentatively identified compounds. Estimated emission factors (EFs) are presented …

2014 Scas Annual Meeting Program

Journal of the South Carolina Academy of Science

No abstract provided.

Genotypic And Phenotypic Characterization Of Aerosolized Bacteria Collected From African Dust Events, Christina A. Wilson, Robin L. Brigmon, Chris Yeager, Garriet W. Smith, Shawn W. Polson

Journal of the South Carolina Academy of Science

Twenty-one bacteria were isolated and characterized from air samples collected in Africa and the Caribbean by the United States Geological Survey (USGS). Isolates were selected based on preliminary characterization as possible pathogens. Identification of the bacterial isolates was achieved using 16S rRNA gene sequence analysis, fatty acid methyl esters (FAMEs) profiling, the BIOLOG Microlog^® System (carbon substrate assay), and repetitive extragenic palindromic (REP)-PCR analysis. The majority of isolates (18/21) were identified as species of the genus Bacillus. Three isolates were classified within the Bacillus cereus senso lato group, which includes Bacillus anthracis, Bacillus thuringiensis, and Bacillus …

Scas Officers And Council Members 2014-2015

Journal of the South Carolina Academy of Science

No abstract provided.

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.

Advances In Molecular Quantum Chemistry Contained In The Q-Chem 4 Program Package, Yihan Shao, Zhengting Gan, Evgeny Epifanovsky, Andrew T. B. Gilbert, Michael Wormit, Shervin Fatehi

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

A summary of the technical advances that are incorporated in the fourth major release of the Q-CHEM quantum chemistry program is provided, covering approximately the last seven years. These include developments in density functional theory methods and algorithms, nuclear magnetic resonance (NMR) property evaluation, coupled cluster and perturbation theories, methods for electronically excited and open-shell species, tools for treating extended environments, algorithms for walking on potential surfaces, analysis tools, energy and electron transfer modelling, parallel computing capabilities, and graphical user interfaces. In addition, a selection of example case studies that illustrate these capabilities is given. These include extensive benchmarks of …

Inhibition Of The Thioesterase Activity Of Human Fatty Acid Synthase By 1,4- And 9,10-Diones, Herman H. Odens

Faculty Works

Fatty acid synthase (FASN) is the enzyme that synthesizes fatty acids de novo in human cells. Although FASN is generally expressed at low levels in most normal tissues, its expression is highly upregulated in many cancers. Consistent with this notion, inhibition of FASN activity has demonstrated potential to halt proliferation and induce cell death in vitro and to block tumor growth in vivo. Consequently, FASN is widely recognized as a valuable therapeutic target. In this report, we describe a variety of 1,4-quinones and 9,10- anthraquinones, including several natural compounds and some newly synthesized compounds, that potently inhibit the thioesterase (TE) …

Unfolded Protein Response Activation Reduces Secretion And Extracellular Aggregation Of Amyloidogenic Immunoglobulin Light Chain, Christina B. Cooley, L. M. Ryno, L. Plate, G. J. Morgan, J. D. Hulleman, J. W. Kelly, R. L. Wiseman

Chemistry Faculty Research

Light-chain amyloidosis (AL) is a degenerative disease characterized by the extracellular aggregation of a destabilized amyloidogenic Ig light chain (LC) secreted from a clonally expanded plasma cell. Current treatments for AL revolve around ablating the cancer plasma cell population using chemotherapy regimens. Unfortunately, this approach is limited to the ∼70% of patients who do not exhibit significant organ proteotoxicity and can tolerate chemotherapy. Thus, identifying new therapeutic strategies to alleviate LC organ proteotoxicity should allow AL patients with significant cardiac and/or renal involvement to subsequently tolerate established chemotherapy treatments. Using a small-molecule screening approach, the unfolded protein response (UPR) was …

Medicinal History Of North American Veratrum, Christopher M. Chandler, Owen M. Mcdougal

Chemistry and Biochemistry Faculty Publications and Presentations

Plants belonging to the genus Veratrum have been used throughout history for their medicinal properties. During the nineteenth and twentieth centuries, phytochemical investigations revealed a host of steroidal alkaloids in Veratrum species, some of which are potent bioactives. This review discusses Veratrum species that grow in North America with a focus on the medicinal history of these plants and the steroidal alkaloids they contain. While significant reviews have been devoted to singularly describing the plant species within the genus Veratrum (botany), the staggering breadth of alkaloids isolated from these and related plants (phytochemistry), and the intricacies of how the various …

Ion Structure And Energetics In The Gas Phase Characterized Using Fourier Transfom Ion Cyclotron Resonance Mass Spectrometry, Chad A. Jones

Theses and Dissertations

In this dissertation, I use Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) to study the structure and energetics of gas phase ions. Infrared multiphoton dissociation spectroscopy (IRMPD) is a technique for measuring the IR spectrum of gas phase ions in a Penning trap. I use this technique to investigate the conformation of cucurbituril complexes, terminal diamines, and protonated amino acids. Cross sectional areas by Fourier transform ion cyclotron resonance mass spectrometry (CRAFTI) is a technique developed by the Dearden lab to measure the cross section of gas phase ions. In this work, I further develop a fundamental understanding of …

Photocatalytic Activity And Stability Of Porous Polycrystalline Zno Thin-Films Grown Via A Two-Step Thermal Oxidation Process, James C. Moore, Robert Louder, Cody V. Thompson

Chemistry

The photocatalytic activity and stability of thin, polycrystalline ZnO films was studied. The oxidative degradation of organic compounds at the ZnO surface results from the ultraviolet (UV) photo-induced creation of highly oxidizing holes and reducing electrons, which combine with surface water to form hydroxyl radicals and reactive oxygen species. Therefore, the efficiency of the electron-hole pair formation is of critical importance for self-cleaning and antimicrobial applications with these metal-oxide catalyst systems. In this study, ZnO thin films were fabricated on sapphire substrates via direct current sputter deposition of Zn-metal films followed by thermal oxidation at several annealing temperatures (300-1200 °C). …

Synthesis Of Homo- And Heterobimetallic NiIi–MIi (M = Fe, Co, Ni, Zn) Complexes Based On An Unsymmetric Ligand Framework: Structures, Spectroscopic Features, And Redox Properties, Denan Wang, Sergey V. Lindeman, Adam T. Fiedler

Chemistry Faculty Research and Publications

Several homo- and heterobimetallic Ni^II–M^II complexes (M^II = Fe, Co, Ni, Zn) supported by an unsymmetric polydentate ligand (L₁³⁻) are reported (L₁³⁻ is the trianion of 2-[bis(2-hydroxy-3,5-tert-butylphenyl)aminomethyl]-4-methyl-6-[(2-pyridylmethyl)iminomethyl]phenol). The L₁³⁻ chelate provides two distinct coordination environments: a planar tridentate {N₂O} site (A) and a tetradentate {NO₃} site (B). Reaction of L₁³⁻ with equimolar amounts of Ni^II and M^II salts provides bimetallic complexes in which the Ni^II ion exclusively occupies the tetragonal A-site and the M^II ion is found …

Small Molecule Tyrosine Kinase Inhibitors Of Erbb2/Her2/Neu In The Treatment Of Aggressive Breast Cancer., Richard L. Schroeder, Cheryl L. Stevens, Jayalakshmi Sridhar

Faculty and Staff Publications

he human epidermal growth factor receptor 2 (HER2) is a member of the erbB class of tyrosine kinase receptors. These proteins are normally expressed at the surface of healthy cells and play critical roles in the signal transduction cascade in a myriad of biochemical pathways responsible for cell growth and differentiation. However, it is widely known that amplification and subsequent overexpression of the HER2 encoding oncogene results in unregulated cell proliferation in an aggressive form of breast cancer known as HER2-positive breast cancer. Existing therapies such as trastuzumab (Herceptin^®) and lapatinib (Tyverb/Tykerb^®), a monoclonal antibody inhibitor …

100th Convocation 2014 Address - Amazing Mice Light Up The Liberal Arts, Marc Zimmer

Convocation Addresses

Connecticut College Professor of Chemistry Marc Zimmer states, "I like to think of our educational system as an intellectual maze. New students, you are standing at the entrance of this fantastic maze, a lush and verdant garden maze..."

He concludes: "We are all, faculty, students and staff tremendously privileged to be sitting here at the entrance of the amazing maze of learning."

High Sensitive Detection Of Cd(Ii) And Pb(Ii) Based On Antimony-Film Covered Pencil Core Electrodes, Shan Chen, Zhao-Yan Zheng, Yi-Min Fang, Li-Qing Zheng, Jian-Jun Sun

Journal of Electrochemistry

In this paper, a pencil core was used as the substrate for an antimony-film electrode for simultaneous detection of Cd(II) and Pb(II) by square-wave anodic stripping voltammetry (SWASV). With the deposition time of 180 s, the low limit of detection (LOD) for the electrode was determined to be 0.075·g?L-1 for Cd(II), while 0.13·g·L-1 for Pb(II) with good reproducibility in low pH solutions (pH = 2). The results show a much lower LOD than that of bismuth-film pencil core electrode. Finally, this antimony-film electrode was successfully applied to determine Cd(II) and Pb(II) in tap water.

A Sensitive And Label-Free Electrochemical Aptasensor Based On Signal Amplification Of Carbon Nanotubes, Chun-Yan Deng, Hui-Min Fan, Juan Xiang, Yuan-Jian Li

Journal of Electrochemistry

A label-free electrochemical sensing electrode for highly sensitive detection of adenosine was constructed based on the signal amplification of carbon nanotubes (CNTs). The change in the interfacial feature of the modified electrode was characterized by electrochemical impedance spectroscopy. Using [Ru(NH₃)₆]³⁺ as the signaling moiety, adenosine with concentrations as low as 0.027 nmol·L^-1 can be selectively detected. Additionally, the fabrication of this present aptasensor was simple, time-saving and cost-effective. Compared with other reported aptasensors, the proposed aptasensor had advantages of excellent sensitivity, selectivity and simplicity, which plays a potential role in development of aptasensor.

Room Temperature Ionic Liquid Templated Meso-Macroporous Material By Self-Assembled Giant Gold Nanoparticles And Its Enhancement On The Direct Electrochemistry Of Cytochrome C, Pei Li, Dong-Ping Zhan, Yuan-Hua Shao

Journal of Electrochemistry

Room temperature ionic liquid (RTIL) is used as a soft-template to organize a meso-macroporous material constructed by self-assembled giant gold nanoparticles which are capped by L-cysteine. First, L-cysteine capped gold nanoparticles can self-assembly to form nanowires and sub-micrometer spherical giant particles due to the static interaction and/or the condensation reaction between the carboxyl and amino groups at the outer terminal of the ligand. Second, the spherical assembled particles can form a quasi-solid gel when grinding with a hydrophobic RTIL, 1-octyl-3-metyllimidazolium hexafluorophosphate. Finally, when the composite gel is coated on a glassy carbon electrode and then polarized by using cyclic voltammetry …

Facile Synthesis Of 1-Alkoxy-1h-Benzo- And 7-Azabenzotriazoles From Peptide Coupling Agents, Mechanistic Studies, And Synthetic Applications, Mahesh K. Lakshman, Manish K. Singh, Mukesh Kumar, Raghu Ram Chamala, Vijayender R. Yedulla, Domenick Wagner, Evan Leung, Lijia Yang, Asha Matin, Sadia Ahmad

Publications and Research

(1H-Benzo[d][1,2,3]triazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP), 1H-benzo[d][1,2,3]triazol-1-yl 4-methylbenzenesulfonate (Bt-OTs), and 3H-[1,2,3]triazolo[4,5-b]pyridine-3-yl 4-methylbenzenesulfonate (At-OTs) are classically utilized in peptide synthesis for amide-bond formation. However, a previously undescribed reaction of these compounds with alcohols in the presence of a base, leads to 1-alkoxy-1H-benzo- (Bt-OR) and 7-azabenzotriazoles (At-OR). Although BOP undergoes reactions with alcohols to furnish 1-alkoxy-1H-benzotriazoles, Bt-OTs proved to be superior. Both, primary and secondary alcohols undergo reaction under generally mild reaction conditions. Correspondingly, 1-alkoxy-1H-7-azabenzotriazoles were synthesized from At-OTs. Mechanistically, there are three pathways by which these peptide-coupling agents can react with alcohols. From 31P{1H}, [18O]-labeling, and other chemical experiments, phosphonium and tosylate derivatives of …

Simple, Label-Free And Non-Instrumented Analyte Quantitation By Flow Distance Measurement In Microfluidic Devices, Debolina Chatterjee

Theses and Dissertations

Rapid determination of the concentrations of molecules related to diseases can provide timely information for treatment options. However, most biomarker quantitation methods require costly and complex equipment. On the other hand, point-of-care systems have less complex instrumentation needs than laboratory-based equipment, but often provide less information; for example, biomarker presence or absence instead of concentration. A complete analysis setup addressing key limitations of both laboratory-based and portable systems is highly desirable. I developed microfluidic devices with visual inspection readout of a target’s concentration from microliter volumes of solution flowed into a microchannel. Microchannels are formed within polydimethylsiloxane (PDMS), and the …

Characterization Of Fall Leaves As A Source Of Cellulosic Ethanol, Justin Burum

Journal of Undergraduate Research at Minnesota State University, Mankato

Ethanol is becoming increasingly popular as a fossil fuel additive or substitute. However, current production of ethanol from corn impacts food prices and appears to have an overall low net yield. New sources need to be identified and new processes developed for ethanol production. Cellulosic ethanol is one such new source. Plant material contains a large amount of cellulose and other polysaccharides which are potential feed stocks for ethanol production. The purpose of this experiment was to characterize the polysaccharide, lignin, and ash content of fall leaves to estimate their potential for ethanol production. A slight modification of the NREL …

N-Methylimidazole Promotes The Reaction Of Homophthalic Anhydride With Imines, J. Liu, Z. Wang, A. Levin, T. J. Emge, Paul R. Rablen, D. M. Floyd, S. Knapp

Chemistry & Biochemistry Faculty Works

The addition of N-methylimidazole (NMI) to the reaction of homophthalic anhydride with imines such as pyridine-3-carboxaldehyde-N-trifluoroethylimine (9) reduces the amount of elimination byproduct and improves the yield of the formal cycloadduct, tetrahydroisoquinolonic carboxylate 10. Carboxanilides of such compounds are of interest as potential antimalarial agents. A mechanism that rationalizes the role of NMI is proposed, and a gram-scale procedure for the synthesis and resolution of 10 is also described.

Effect Of Sweeteners On The Renin-Angiotensin System In Rats, Jacob Ball

Journal of Undergraduate Research at Minnesota State University, Mankato

Normal abundant dietary sugars such as fructose and sucrose can contribute to hypertension and other health issues. To avoid these health complications, many individuals use artificial sweeteners. An equivalent intake of some artificial sweeteners also can lead to hypertension. However, Stevia, a sweetener that is isolated from a Paraguayan plant, was shown in relevant literature to decrease blood pressure in both rat specimens and humans. The general purpose of this research project was to study the effect of Stevia, saccharin, and sucrose on the expression of two key components of the renin-angiotensin- aldosterone system (RAAS): prorenin receptor (PRR) and angiotensin …

Synthesis And Biological Evaluation Of N-Heterocycles For Activity On Monoamine Transporters And Exploration Of Iridium Chemistry For Synthesis Of Medicinally Important Molecules, Tushar D. Apsunde

LSU New Orleans Theses and Dissertations

The focus of these studies was directed towards the synthesis of novel N-heterocyclic compounds and pharmacological evaluation of these compounds for activity at monoamine transporters. A series of novel piperidine and pyrrolidine analogues were prepared from commercially available starting material with a three and four step synthetic method, respectively. A variety of substituents on the aromatic ring were incorporated to achieve a diverse library of compounds. The preliminary binding studies of piperidine molecules showed strong affinity towards serotonin transporters and moderate affinity towards dopamine transporters. The focus of further studies was directed towards utilization of iridium catalysis for the development …