Physical Sciences and Mathematics Commons^™

Kinetics And Mechanism Of The Catalysis Of The Decomposition Of Hydrogen Peroxide By Schiff Base Complexes Of Copper(Ii)., Timothy Kum Beng

Electronic Theses and Dissertations

Spectroscopic studies have been used to describe the mechanism of the decomposition of hydrogen peroxide by solutions of a dimeric Cu(II) complex of a dissymetric Schiff base, [CuSALAD]₂.H₂O, and imidazole or methyl substituted imidazoles, B, which form monomeric CuSALAD.B₂ complexes, in aqueous ethanol solvent. Freezing point depression and vapor pressure lowering studies were carried out to confirm the dimeric nature of the [CuSALAD]₂.H₂O complex that had been previously reported. The stoichiometry of the [CuSALAD]₂.H₂O-imidazole equilibrium was extensively studied pointing to a 1:4 stoichiometry. The CuSALAD.B₂ adducts …

Electrochemical Investigation Of Anthraquinone Tagged Oligonucleotides And Electrodes, Adam N. Mullenix

Doctoral Dissertations

The DNA double helix is one of the most studied structures in modern science. These molecules provide the basic blueprint for all life as it is presently known to exist. Continuing studies of this structure, and the implications that come with them, currently yield a constantly growing base of knowledge for the study of drug interactions, specifics in the role of the sequence of bases in the DNA chain, and an understanding of the small structural abnormalities and the resulting benefits and problems in the human genome. The research presented herein attempts to examine such interactions using anthraquinone-based modifications for …

Analysis Of Benzo(A)Pyrene-Induced Gene Expression Changes In Fisher 344 Rat Liver By Affymetrix Microarray And Quantitative Real-Time Pcr, Alhaji Umar N’Jai

Dissertations

No abstract provided.

Synthesis And Characterization Of A Recombinant Thrombin Inhibitor, Joel Lwande

Masters Theses

The final step of the blood coagulation cascade is catalyzed by thrombin, a serine protease. Like most enzyme activities, thrombin activity encounters inhibition from both direct and indirect inhibitors. A new thrombin inhibitor peptide named theromin was recently isolated from the leech Theromyzon tessulatum, and it is the most potent thrombin inhibitor isolated to date. Theromin is made up of 67 amino acid residues, out of which 16 are cysteines engaged in 8-disulfide bridges.

We synthesized the theromin gene and expressed the protein in Eschericia coli. We purified the recombinant protein and carried out thrombin inhibition assays that …

Ir Studies Of The Interaction Of Surfactants And Polyelectrolytes Adsorbed On Tio2 Particles, Haiyan Li

Electronic Theses and Dissertations

Polymers/surfactants are used to control and modify the interfacial properties of particulate suspensions. The resulting properties are dependent on the amount of adsorbed surfactants/polymers on the surface as well as the nature of the aggregated structures. Often these interactions are complex and not well understood. In this thesis we have used Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) to identify surfactant, mixed surfactant, polyelectrolyte and mixed polyelectrolyte surfactant structures formed on charged Ti0₂ particles. In addition, the change occurring to the structure of an adsorbed polymer layer on Ti0₂ to flowing suspension of silica particles was studied. A …

Ellipsometric Measurement Of Swelling Properties Associated With Ph Responsive Hydrogels In Solution, James F. Patton

Masters Theses

Previous investigations have demonstrated that aqueous solutions containing hydrogels using 2-hydroxyethyl methacrylate (2-HEMA) as one of the monomer components swell reversibly under variable conditions of pH, temperature, and ionic strength, based upon weight gain ratios. A more unique approach will be employed to measure swelling properties associated with pH responsive hydrogels in buffered solutions, namely ellipsometry. Traditionally ellipsometry has been used to measure thickness of materials on a nanoscale dimension under ambient conditions. Finally, more novel approaches of employing hydrogel swelling response properties will be investigated; including response to glucose and enzyme loading schemes. The goal of our project will …

Effect Of Nanoscale Confinement On The Structure And Properties Of Single Conjugated Polymer Molecules, Pradeep K. Koyadankizhakkedath

Doctoral Dissertations

The research presented in this thesis was motivated by questions on the effect of nanoscale confinement on molecular conformation and related photophysical properties of conjugated polymers. Using microdroplet techniques as a method of isolating single molecules of various poly[phenylene vinylenes] we discovered that poly[2-methoxy-5- (2’-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) and poly[2-Methoxy-5-(2'- ethylhexyloxy)-1,4-(cyanovinylene)phenylene] (CN-PPV) can be deposited on precleaned glass substrates with unique transition moment orientation. Structural investigation using a combination of fluorescence emission pattern imaging, atomic force microscopy and polarization anisotropy measurements revealed that individual polymer nanostructures had a high degree of intra-molecular with the long axis of the conjugated segment oriented …

Capillary Liquid Chromatography Using Micro Size Particles, Yanqiao Xiang

Theses and Dissertations

High speed and/or high efficiency separations can be realized using small particles (~ 1 µm) in liquid chromatography (LC). However, due to the large pressure drop caused by small particles, conventional LC pumping systems cannot satisfy the pressure requirements needed to drive the mobile phase through the column. Use of ultrahigh pressure, elevated temperature, or both can overcome these pressure limitations and allow the use of very small particles for high speed and/or high efficiency separations.

In this dissertation, the use of ultrahigh pressures with and without elevated temperatures in capillary LC is described. Very fast separations of various samples …

Metal Ion Imprinted Polymers For Biomolecular Recognition, Len A. Harris

Masters Theses

Protein recognition by HPLC, based on histidine residues, was achieved by incorporating a copper chelating ligand covalently bonded to a polystyrene/divinyl benzene substrate, into column packing. The metal ion was bonded to the substrate in two ways: randomly, where the copper was bound to the ligand after the substrate polymerization and imprinted, where the copper was bound to the ligand before the substrate polymerization. The effect of this templating was measured by protein separation parameters of the resulting HPLC chromatographs. The hypothesis of this thesis is the imprinted substrate will have a higher copper content, and with coppers affinity toward …

Identification Of A Putative Caspase Protein In S.Commune, Emma Ester Bendaña Flores

Honors Theses

Caspases are the proteins responsible for apoptosis in cells. Others have recently identified a caspase in Saccharomyces cerevisiae, a unicellular fungus.2, 3, 4 Isolation of a caspase protein from Schizophyllum commune will allow for the examination of a caspase in a simple multicellular organism.4 The S.cerevisiae caspase sequence was used to search the genomes of several fungi and identify similar sequences. Regions with high sequence identity in the aligned sequences were used to design degenerate PCR primers. The sequence of the resultant PCR product was then used to prepare primers for 3'RACE and determine the 3'end of the sequence. Through …

Binding Studies Of 2-Acetylnaphthalene With Native And Methylated Cyclodextrins Using Fluorescence Spectroscopy : The Use Of Gas Chromatography/Mass Spectrophotometry To Analyze Organic Contaminants In Local Waters, Amy L. Payeur

Honors Theses

The main goal of this work: was to explore complexes formed between 2-acetylnaphthalene (2-AN) and unsubstituted α, β, and y-cyclodextrins as well as 2-An and methylated α, β and y-cyclodextrins. The substituted cyclodextrins used were trimethyl-α-cyclodextrin (TM-α-CD), trimethyl-β-cyclodextrin (TM-β-CD), trimethyl-y-cyclodextrin (TM-y-CD), and dimethyl-β-cyclodextrin (DM-β-CD). For the trimethylated cyclodextrins, all three of the -OH groups on the cyclodextrin ring are replaced by -OCH3 groups. The dimethylated cycloextrin on the other hand only has 18 of the 21 -OH groups replaces by -OCH3 groups. Binding constants were determined for complexes using fluorescence quenching experiments at varying temperatures. Thermodynamic parameters of complex formation …

Velocity And Temperature Characterization Of The First Vacuum Stage Expansion In An Inductively Coupled Plasma - Mass Spectrometer, William Neil Radicic

Theses and Dissertations

The inductively coupled plasma - mass spectrometer (ICP-MS) is the analytical instrument of choice for trace element detection and quantification. Despite the popularity of ICP-MS, significant degradation in sensitivity and precision occurs as the result of matrix and instrument-induced effects. The sources of these effects are not well understood, characterized, or correlated to particular plasma operating condition settings or matrix compositions and involve both neutral and charged species. The purpose of this study is to characterize the behavior of metastable Ar (I) atom and Ca (II) ion through the measurement of Doppler velocities and fluorescence line width "temperatures."

For the …

N9 Alkylation And Glycosylation Of Purines; A Practical Synthesis Of 2-Chloro-2'-Deoxyadenosine, Minghong Zhong

Theses and Dissertations

(a) The Robins reagent [2-acetamido-6-O-(diphenylcarbamoyl)purine] was utilized for glycosylation under Lewis acid conditions. Regioselectivity of glycosylation depends on the glycosyl donor and its 2-O- or 2-N-protecting group. Regioselective N9 glycosylation of 2-acetamido-6-O-(diphenylcarbamoyl)purine with problematic glucosamine has been accomplished by protecting the amino function as a phthalimido group with consequent stabilization of the oxocarbenium cation, and lowering the activation energy by introduction of trichloroacetimidate at the anomeric carbon.

(b) 6-Heteroaryl functions [6-(1,2,4-triazol-4-yl) and 6-(imidazol-1-yl)] were introduced into purine derivatives for regioselective N9 alkylation. The regiospecificity of alkylation mainly results from steric effects due to the coplanar conformation of the two linked …

Compatibilizing Polymer Blends Using Reactive Telechelic Oligomers And Copolymers, Charles Paul O'Brien

Doctoral Dissertations

The compatbilization of polymer blends via reactive compatibilization and block copolymers was studied. The result presented in this thesis suggest that the process of reactive compatibiliaztion provides a mechanism by which blocky copolymeric compatibilizers can be formed during processing, as demonstrated by the changes in the mechanical and optical properties of the phase separated polymer blends. The results also show, however, that the presence of unreacted smaller oligomers can act as a plasticizer in the blend and can thus detrimentally affect the mechanical properties of the blend if any remains after processing. Careful control of the mixing conditions or post …

Structural Studies Of Superacidic Systems Using Neutron And High Energy X-Ray Diffraction, Syliva Ellen Mclain

Doctoral Dissertations

The structure of two superacids in the liquid phase, hydrogen fluoride and fluorosulfuric acid, have been determined by neutron and high energy X-ray diffraction in this study. In addition the structure of a molecular Lewis acid, BF₃, has been determined for the liquid state as well as the supercritical state. Experiments were also performed on solutions of the hydronium ion in fluorosulfuric acid by neutron and X-ray diffraction as well as by Raman spectroscopy.

In addition this thesis presents the design and construction of sample cells for neutron and X-ray scattering experiments and the design and construction of …

Determination Of Lactose By Reversed-Phase High Performance Liquid Chromatography., Danessa Leann Sexton

Electronic Theses and Dissertations

Lactose is the common disaccharide found in dairy products. It can, however, be a source of discomfort for those whom are lactose intolerant. Therefore, it is necessary to accurately, reliably, and efficiently determine the lactose content of foods. The goal of this research was to develop a reversed-phase HPLC method with UV detection for the determination of lactose. Aminobenzoic acid was used to prepare a derivative, making detection possible in the 300-360 nm region. The stationary phase is a C8 column, with 85% methanol 15% water mixture at pH 5 as the mobile phase. A linear response of peak area …

Large-Scale Expression And Purification Of Gst-Caveolin Fusion Proteins, Deidre L. Carroll

McCabe Thesis Collection

In this thesis, I will discuss the study I conducted from June 2, 2003 to July 31, 2003 at the University of Oklahoma Health Sciences Center Dean A. McGee Eye Institute, facilitated by Dr. Michael Elliott, funded by the Undergraduate Biomedical Education Program at Langston University, expressing and purifying GST-Cav~olin fusion proteins on a large-scale. Caveolins are the principle constituents of caveolae. Caveolae are flask-shaped invaginations of the plasma membrane. Caveolae are most abundant in endothelial cells, fibroblasts, and myocytes (Smart et al. 1999). These structures participate in three main areas of cell physiology: endocytosis (Henley et al. 1999), cholesterol …

A Parametric Reactive Distillation Study: Economic Feasibility And Design Heuristics, Craig Alan Hoyme

Doctoral Dissertations

The integration of reaction and distillation into a single column is called reactive distillation or catalytic distillation. Reactive distillation provides many benefits such as reduced capital and operating costs, circumventing non-reactive azeotropes, and overcoming equilibrium limited reactions. Industry has been successful in applying reactive distillation; however the integration of reaction and distillation is not applicable for all reaction/separation systems and it is not always clear when reactive distillation is a feasible design alternative.

Heuristics or rules-of-thumb are an integral part of process systems engineering and are used to provide initial guidance and insight for the analysis of process feasibility and …

Studies Of Reversible Inhibition, Irreversible Inhibition And Activation Of Alkaline Phosphatase By Capillary Electrophoresis, Angela Randall Whisnant

Masters Theses

Reversible inhibition, irreversible inhibition, and activation of calf intestinal alkaline phosphatase (EC 3.1.3.1) have been studied by capillary electrophoresis. The capillary electrophoretic enzyme-inhibitor assays were performed by electrophoretically mixing zones of inhibitor and enzyme in a substrate-filled capillary. Enzyme inhibition was indicated by a decrease in product formation detected in the capillary by laser-induced fluorescence. Reversible enzyme inhibitors could be quantified by Michaelis-Menten treatment of the electrophoretic data. Reversible, competitive inhibition of alkaline phosphatase by sodium vanadate and sodium arsenate has been examined. The calculated K_i value for the capillary electrophoretic enzyme-inhibitor assays was 2.1 µM for sodium vanadate …

Development Of Novel Substrates And Sampling Techniques For The Analysis Of Drugs And Model Environmental Pollutants Via Surface Enhanced Raman Spectroscopy (Sers), Marco Antonio De Jesús

Doctoral Dissertations

Surface Enhanced Raman Spectroscopy (SERS) has shown promise for the analysis of environmental and pharmaceutically relevant compounds due to its tremendous enhancement of Raman signals and the large amount of structural information provided by the technique. Despite these advantages, SERS has not been established as a routine analytical tool due to limitations in the analytical figures of merit such as reproducibility and linear dynamic range. This is due in part to the fact that the continuous irradiation of the laser beam over the SERS substrate can promote the rapid decomposition of sample analytes which significantly broaden and diminish the intensities …

Role Of Iron In The Mechanism Of Asbestos-Induced Apoptosis In Human Lung And Pleural Target Cells, Aleksander Baldys

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Occupational exposure to asbestos has been associated with increased incidence of pulmonary interstitial fibrosis, mesothelioma of the pleura, and bronchogenic carcinoma. Although the mechanism by which asbestos causes cancer remains unknown, iron associated with asbestos is thought to play a role in the pathogenic effects of fibers.

The aim of this research was to examine and compare the asbestos-induced signaling phenomena in relevant human lung and pleural target cells, and to determine the role of iron from asbestos fibers in these events. Exposure of human airway epithelial (A549) cells, human pleural mesothelial (MET5A) cells, and normal human small airway epithelial …

Synthetic Studies On Anticancer Compounds: The Tylophorinines, Conrad Gracjan Kaczmarek

Masters Theses

This thesis describes synthetic studies in the area of alkaloid chemistry, specifically, potent anticancer compounds: the tylophorinines.

Tylophorinine is a naturally occurring compound found in the Monarch butterfly and plants of the genus Tylophora. Described here is a concise methodology for stereoselective synthesis of this compound, and analogs, starting from simple, naturally occurring compounds. The synthetic strategy represents a simplification in synthesizing tylophorinines, and would allow numerous other tylophorinines with similar chemical structure to be conveniently synthesized in an analogous fashion.

Further, the tylophorinines are convenient compounds for determining where a cancer cell may be most effectively attacked. Numerous …

Genetic Analysis Of Acetone Carboxylase In Azotobacter Vinelandii, Jessica Gardner

Undergraduate Honors Capstone Projects

Acetone carboxylase, an inducible multimeric enzyme found in several bacteria, catalyzes the carboxylation of acetone to produce acetoacetate. This is an important reaction for the bacteria because, upon addition of coenzyme A, the acetoacetate can be converted to acetyl-CoA, a common metabolic intermediate. Azotobacter vinelandii, one of the bacteria that produces acetone carboxylase, has two different genes encoding this enzyme. We knocked out the first of these by disrupting it with a kanamycin cassette to help us understand the function of the second gene. Knocking out the gene will also make possible the use of site-directed mutagenesis to further study …

Fluorescence Detectors For Proteins And Toxic Heavy Metals, Uchenna Prince Paul

Theses and Dissertations

An inexpensive detector for proteins is described. The detection technique was based on two-photon excitation intrinsic protein fluorescence using a visible 532 nm diode-pumped nano laser as the excitation source. Proteins that exhibit intrinsic fluorescence must contain at least one tryptophan, tyrosine, or phenylalanine residue in their amino acid sequences. The detector was characterized and was found to have a detection limit of 4 micro-molar for tryptophan, 22 micro-molar for tyrosine and 500 micro-molar for phenylalanine. Bovine serum albumin, a serum protein with 3 tryptophan residues in its amino acid sequence was also used to characterize the detector. It was …

Analysis Of Clinically Important Compounds Using Electrophoretic Separation Techniques Coupled To Time-Of-Flight Mass Spectrometry, Zlatuse Durda Peterson

Theses and Dissertations

Capillary electrophoretic (CE) separations were successfully coupled to time-of-flight mass spectrometric (TOFMS) detection for the analysis of three families of biological compounds that act as mediators and/or indicators of disease, namely, catecholamines (dopamine, epinephrine, norepinephrine) and their O-methoxylated metabolites (3-methoxytyramine, norepinephrine, and normetanephrine), indolamines (serotonin, tryptophan, and 5-hydroxytryptophan), and angiotensin peptides. While electrophoretic separation techniques provided high separation efficiency, mass spectrometric detection afforded specificity unsurpassed by other types of detectors.

Both catecholamines and indolamines are present in body fluids at concentrations that make it possible for them to be determined by capillary zone electrophoresis coupled to TOFMS without employing any …

An Evaluation Of Formate As An Electron Donor To Facilitate Palladium (Pd) - Catalyzed Destruction Of Chlorinated Aliphatic Hydrocarbons, Matthew D. Welling

Theses and Dissertations

Chlorinated aliphatic hydrocarbons (CAHs) such as trichloroethylene (TCE), tetrachloroethylene (PCE), and trichloroethane (TCA) are probable human carcinogens that have been used widely within the DoD, primarily as solvents for cleaning and metal degreasing. These compounds are frequently found to be groundwater contaminants. In fact, TCE and PCE are the first and third most commonly detected groundwater contaminants nationwide. The focus of this study was to determine the effectiveness of using a palladium (Pd) catalyst with formate as a reductant to treat CAH-contaminated groundwater. TCE was used as a model CAH. Other investigators have focused on hydrogen gas (H₂) …

Aerobic Biodegradation Of Alternative Fuel Oxygenates In Unsaturated Soil Columns, Kevin A. Mares

Theses and Dissertations

Groundwater contamination problems caused by methyl-tertiary butyl ether (MTBE) in subsurface waters have prompted the search for a gasoline oxygenate replacement. In order to avoid the problems encountered with MTBE, it is prudent to evaluate the fate and transport in the subsurface of proposed replacements, such as ethanol. In this study, ethanol transport and degradation in unsaturated soil was investigated using a series of eight soil columns. This preliminary study was to see if the soil column system components functioned properly, how similarly the eight soil columns performed, and if soil oxygen concentration affected degradation of ethanol. Tracer tests, using …

Characterization Of Chlorinated Solvent Degradation Profile Due To Microbial And Chemical Processes In A Constructed Wetland, Teresa A. Sobolewski

Theses and Dissertations

Perchloroethene (PCE) and its degradation products are among the most common organic groundwater contaminants in the United States. Constructed wetlands are a relatively new approach to dealing with this contamination problem. With their upward flow capability it is possible to introduce an aerobic and anaerobic environment with a consortium of microorganisms available to degrade the contaminants to within acceptable levels established by the Environmental Protection Agency (EPA). This study is a follow-up to the previous two years of research on PCE degradation in cell 1 at Wright-Patterson Air Force Base. This thesis was conducted in order to study the wetland …

An Evaluation Of Formic Acid As An Electron Donor For Palladium (Pd) Catalyzed Destruction Of Nitroaromatic Compounds, Mark R. Stevens

Theses and Dissertations

The Department of Defense is responsible for over 2,000 hazardous waste sites containing nitroaromatic compounds (NACs) such as 2,4,6-TNT, 2,4- and 2,6-DNT that resulted from the production and use of munitions throughout the nation and world, NACs are typically persistent in natural environments, though they can be oxidized or reduced under engineered conditions, NACs and their reduction products are toxic chemicals and suspected human carcinogens, Both TNT and 2,4-DNT are listed as priority pollutants by the U,S EPA, This study investigates the effectiveness of using a palladium (Pd) catalyst in concert with formic acid as an electron donor to reduce …

Thermochemical Properties Of Small Oxygenated Sulfur Hydrocarbons And Kinetics - Reaction Pathways Of Methylthiomethyl Radical With Oxygen, Fei Jin

Theses

The thermochemical properties on CH₃SCH₂OOH and the corresponding two radicals resulting from loss of H atom: CH₃SCH₂OO and CH₂SCH₂OOH are important to understand the stability, reaction paths and kinetics of reactions of dimethyl sulfide and other sulfur hydrocarbons (sulfides) in the atmosphere and combustion processes. Thermochemical properties for species and transition states in the methylthiomethyl radical (CH₃SCH₂) + O₂ reaction system are analyzed to evaluate reaction paths and kinetics under these conditions. Isodesmic working reaction are employed to determine the enthalpies of formation …