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Sites of Reactivity During Ligand-Exchange Reactions in Octahedral Group VIB Metal Carbonyls

Description: The site of initial metal-carbonyl bond-breaking during ligand-exchange reactions in a series of octahedral metal carbonyls of the type (L2)M(CO)4 (M = Cr, Mo, W; L2 = diphos, phen, dipy) has been determined employing infrared spectroscopy and Fourier transform nuclear magnetic resonance spectroscopy. The results of this study reveal, for all metal carbonyl complexes of the type mentioned above, that loss of CO occurs exclusively at an axial position (cis to the bidentate ligand, I^)• The dynam… more
Date: December 1979
Creator: Asali, Khalil Jamil
Item Type: Refine your search to only Thesis or Dissertation
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Studies of L-Asparaginase from Lactobacillus Plantarum

Description: This study is concerned with the regulation of Lasparaginase (LA) in the cell-free crude extracts from Lactobacillus plantarum (ATCC8014). A previously reported finding that adenosine triphosphate (ATP) inhibits the action of LA in crude extracts was confirmed. The study was extended to include the mono-, di-, and triphosphates of adenosine, guanosine, cytidine, and uridine. These compounds were also shown to inhibit LA activity. These andother studies revealed that LA appears to be an alloster… more
Date: May 1979
Creator: Nalepka, Edward R.
Item Type: Refine your search to only Thesis or Dissertation
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Electric Dichroism Spectroscopy in the Vacuum Ultraviolet

Description: When a molecule, which possess a permanent dipole moment is exposed to an intense electric field, its absorption spectrum may be altered. These alterations are manifest as shifts in energy and as changes in band shape and intensity. The electric dichroism of absorption bands can be used to probe the excited state that is formed when a molecule undergoes a transition. The properties that may be investigated include transition polarization, excited state dipole moment and mean polarizability, and… more
Date: May 1978
Creator: Causley, Gary C.
Item Type: Refine your search to only Thesis or Dissertation
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Carbon-13-carbon-13 Coupling Constants in Fluorene and O-Methylbenzene Derivatives

Description: A model system to calculate single-path coupling constant was devised to see if the couplings are additive in a system which has a dual-pathway. The system chosen was o-methyl-13C-benzoic acid. Because of anomalies in the data, the series was extended. Hybridization of the label appeared to have relatively little effect, and the conformation of the substituents very important.
Date: August 1977
Creator: Kattner, Richard M.
Item Type: Refine your search to only Thesis or Dissertation
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The Chlorination of Amino Acid in Municipal Waste Effluents

Description: In model reaction systems to test amino acids in chlorinated waste effluents, several amino acids were chlorinated at high chlorine doses. (2000-4000 mg/1). Amino acids present in municipal waste effluents before and after chlorination were concentrated and purified using cation exchange and Chelex resins. After concentration and cleanup of the samples, the amino acids were derivatized by esterification of the acid functional groups and acylation of the amine groups. Identification and quantifi… more
Date: July 1977
Creator: Burleson, Jimmie L.
Item Type: Refine your search to only Thesis or Dissertation
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Organometallic Precursors to Cyclic Organosilanes

Description: This investigation deals with the preparations of cyclic organosilanes via two different types of organometallic precursors: borane adducts to chlorovinylsilanes and tertbutyllithium adducts to chlorovinylsilanes. The regiospecificity of the hydroboration of various types of boranes to chlorovinylsilanes was studied by three different methods. It was found that, by using bulky hydroborating agents, about 80% isomerically pure terminal borane adducts to chlorovinylsilanes could be obtained. Whil… more
Date: May 1977
Creator: Lim, Thomas Fay-Oy
Item Type: Refine your search to only Thesis or Dissertation
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Studies of the Mechanisms of Reactions of Binary Metal Carbonyls

Description: A kinetic study of the reactions of Group VI-B hexacarbonyls with primary amine and halide ligands was undertaken in order to determine the possible mechanisms of these reactions. As well as the expected dissociative pathway, the reactions with the primary amines were seen to proceed by a concurrent pathway which was dependent upon the ligand concentration. Since nitrogen donor ligands are expected to be poor donor ligands, the mechanism proposed was a "dissociative interchange" mechanism which… more
Date: May 1977
Creator: Pardue, Jerry E.
Item Type: Refine your search to only Thesis or Dissertation
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Kinetics and Mechanism of Reactions of Disubstituted Octahedral Metal Carbonyls with Phosphorus Donor Ligands and Germanium Tetraiodide

Description: The kinetics and mechanism of the reactions of (tmpa)W-(CO)^ and (tmen)W(CO)^ (tmpa = N,N,N',N'-tetramethy1-1,3-diaminopropane and tmen = N,N,N1,N1-tetramethylethylenediamine) with four phosphorus donor ligands (triisopropyl phosphite, triphenyl phosphite, triphenylphosphine and "constrained phosphite", 4-methyl-2,6,7-trioxa-l-phosphabicylo[2.2.2]octane) in xylene have been investigated in detail. These reactions were found to take place by the ring-opening of the bidentate ligand in a reversib… more
Date: August 1976
Creator: Moradi-Araghi, Ahmad
Item Type: Refine your search to only Thesis or Dissertation
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The Determination of Organic-Bound Chlorine Levels in Municipal Wastewaters After Treatment with Heavy Chlorine Doses

Description: The development of an analytical method for the determination of total organic-bound chlorine (TOCl) produced during the chlorination of municipal wastewater effluents is presented. Sewage effluent from the Denton, Texas municipal treatment plant was chlorinated at high chlorine doses (1000 - 4000 ppm), as well as typical treatment levels. Chlororganics present in the wastewater, before and after chlorination, were concentrated by adsorption on Amberlite XAD-2 macroreticular resin, followed by … more
Date: May 1976
Creator: Smith, Garmon B.
Item Type: Refine your search to only Thesis or Dissertation
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Magnetic Properties of Metal(II) Schiff Base Complexes

Description: Ligands prepared from various combinations of aldehydes and ketones with the appropriate aminealcohol were complexed with cupric acetate monohydrate. The complexes with O,NO or N,N,O donor atoms were synthesized to study the influences of the ligand on molecular structure, spin-spin interaction, and on the value of the exchange integral. The magnetic data indicated that of the eight Cu(II) complexes discussed, two behaved differently from known analogous compounds. Cu (benzoylacetone :ethanola… more
Date: May 1976
Creator: Hines, Mary Katherine
Item Type: Refine your search to only Thesis or Dissertation
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Regulation of Pyridine Nucleotide Metabolism in Saccharomyces cerevisiae

Description: The levels of total nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), and their redox states were determined as the function of growth in S. cerevisiae. Cells growing in a medium containing 0.8% glucose exhibit two phases of exponential growth, utilizing glucose and ethanol, respectively. The NAD pool is 50% reduced during both stages of growth while the NADP pool is 67% reduced in glucose growth and 48% reduced in ethanol growth. The NAD/NADP ratio… more
Date: May 1976
Creator: Ting, Haung-yu
Item Type: Refine your search to only Thesis or Dissertation
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Spectroscopic Investigation of Some Allyl Alkali Metal Compounds

Description: To gain better understanding of the nature of the carbonmetal bonding in 3-neopentylallyl alkali metal (5,5-dimethyl- 2-hexenyl alkali metal) systems, an investigation is extended to 3-neopentylallylpotassium. In addition, pertinent data on the 3-neopentylallyl systems are re-examined in an attempt to understand the trends in the bonding habits, as affected by the solvent, the cation and the temperature.
Date: May 1976
Creator: Moore, Michael L.
Item Type: Refine your search to only Thesis or Dissertation
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Chemical Cleavage of Human Phosphoglucose Isomerase at Cysteine

Description: The present study has resulted in the development of a procedure for the specific chemical fragmentation of human phosphoglucose isomerase into a minimal number of peptides. A two-cycle procedure for cleaving the protein with 2-nitro-5- thiocyanobenzoic acid results in four primary peptides and three overlap peptides. The peptides can be readily separated on the basis of their size by using sodium dodecyl sulfate polyacrylamide gel electrophoresis. Preliminary peptide alignments have been consi… more
Date: December 1975
Creator: Conn, Worth R.
Item Type: Refine your search to only Thesis or Dissertation
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Copper (II) Complexes with Deprotonated N-(2-hydroxyethyl)ethylenediamine

Description: This thesis reports the synthesis and characterization of two new copper(II) halide complexes with deprotonated N-(2-hydroxyethyl)ethylenediamine behaving as a bidentate. The magnetic properties of the new copper(II) complexes were studied from room temperature to liquid nitrogen temperatures. The magnetic data show that both complexes exhibit antiferromagnetic interactions with a singlet ground state and a thermally accessible triplet excited state. Magnetic data and infrared spectra indicate … more
Date: December 1975
Creator: Miller, Toney G.
Item Type: Refine your search to only Thesis or Dissertation
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The Correlation Between Carbon-Proton and Proton-Proton Coupling Constants

Description: The correlation between the carbon-proton and proton-proton coupling constants have been studied in various 13 systems. Isocrotonic acid-carboxyl-3C, crotonic acid- 13 13 carboxyl-3C, and 5-norbornene-2-carboxylic acid-carboxyl-3C- 1,5,6,7,7-hexachloro were synthesized and their carbonproton coupling constants were analyzed. Nmr studies showed the magnitudes of the carbon-proton coupling constants to correlate well with analogous protonproton coupling constants, although the values of the coupl… more
Date: December 1975
Creator: Seiwell, Ruth R.
Item Type: Refine your search to only Thesis or Dissertation
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Denaturation, Renaturation and Other Structural Studies on Phosphoglucose Isomerases

Description: Structural properties of phosphoglucose isomerases isolated from a variety of species have been compared by peptide fingerprinting, predicted amino acid sequence homologies and by denaturation and renaturation studies. The enzymes are more readily denatured in guanidinium chloride than in urea, and the isomerase isolated from yeast is more stable toward acid pH than the rabbit muscle enzyme. The rates of guanidinium chloride-induced denaturation are markedly increased by ionic strength and decr… more
Date: December 1975
Creator: Young, Clint D.
Item Type: Refine your search to only Thesis or Dissertation
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Magnetic Properties of Copper (II) Complexes of Schiff Bases

Description: The synthesis and characterization of two new Schiff base copper(II) complexes are reported. These are Cu(acac: 2-amino-l-phenylethanol) and Cu(acac:2-amino-l-butanol). The ligands, derived from acetylacetone and the appropriate aminoalcohol, are dibasic tridentates with 0,N,O donor atoms. The magnetic properties of the complexes were studied at several temperatures between 78 OK and 296 OK. The magnetic moment of Cu(acac:2-amino-l-phenylethanol) varied little with temperature, and that of Cu(a… more
Date: August 1975
Creator: Jones, William James
Item Type: Refine your search to only Thesis or Dissertation
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Stereochemical Elucidation Of The Tetrahydro [2.2]paracyclophane System

Description: The purpose of this investigation is to study the Birch reduction products of [2.2lparacyclophane and of [2.2]paracyclophane- 2-carboxylic acid. The tetrahydro Birch reduction product of [2.2]paracyclophane is shown to be dl stereoisomer, with the olefins of the upper deck only partially overlapping with the olefins of the lower deck. This stereochemical elucidation is accomplished by means of a complete proton nmr analysis of the tetraepoxide derivative. A proposed mechanism supported by VB (v… more
Date: August 1975
Creator: Song, Ban-Huat
Item Type: Refine your search to only Thesis or Dissertation
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The Crystal and Molecular Structure of 2, 2' bipyridylglycinatochloro Copper (II) Dihydrate

Description: The three-dimensional x-ray structure of 2,2'-bipyridylglycinatochloro copper(II) dihydrate has been fully refined to a final R factor of 0.081. The bipyridyl and glycine ligands are arranged about the central copper atom in a square planar configuration while the chlorine atom is 2.635 angstroms above this plane directly over the copper atom. This unusually long distance is explained by the positioning of a glycine group on the opposite side of the square plane, resulting in a distorted octahe… more
Date: May 1975
Creator: Neitzel, Conrad J.
Item Type: Refine your search to only Thesis or Dissertation
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Hyperconjugative Interactions in Silylanilines

Description: The purpose of the present work is to study the bonding interactions between the substituents and the ring π system for a series of ortho and para MeₙH₃₋ₙM (M = C or Si, n = 0-3) substituted N,N-dimethylaniline . Both ground and excited-state interactions were studied and their magnitudes determined. The experimental data were then used in conjunction with molecular orbital calculations to differentiate among inductive, hyperconjugative, and d-pπ interactions on the ground and excited states. O… more
Date: May 1975
Creator: Jung, Il Nam
Item Type: Refine your search to only Thesis or Dissertation
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Isolation and Characterization of Proteus vulgaris Methylglyoxal Synthetase

Description: Methylglyoxal synthetase, which catalyzes the formation of methylglyoxal and inorganic phosphate from dihydroxyacetone phosphate, was found in extracts of Proteus vulgaris. An efficient purification procedure utilizing ion exchange column chromatography and isoelectric focusing has been developed. Homogeneity of the enzyme preparation was confirmed by polyacrylamide gel electrophoresis and rechromatography.Two components of methylglyoxal synthetase were obtained upon isoelectric focusing. A com… more
Date: May 1975
Creator: Tsai, Pei-Kuo
Item Type: Refine your search to only Thesis or Dissertation
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Synthesis and Study of Glutaryl-S-(ω-aminoalkyl)-L-cysteinylglycines as Inhibitors of Glyoxalase I

Description: This thesis describes the synthesis and preliminary enzymatic study of glutaryl-S-(8-aminooctyl)-L-cysteinylglycine and glutaryl-S-(10-aminodecyl)-L-cysteinylglycine as inhibitors of glyoxalase I. These analogs of glutathione were prepared as potential ligands for affinity chromatography purification of glyoxalase I. The compounds were synthesized by a seven-step procedure in overall yields of 24% for the octyl analog and 33% for the decyl analog. Both compounds exhibited mixed type inhibition … more
Date: May 1975
Creator: Phillips, Gerald Wayne
Item Type: Refine your search to only Thesis or Dissertation
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Inhibitors of Dihydrofolate Reductase, 8-Oxapteridines

Description: The biological activities of some homeosterically related analogs of dihydrofolic acid have been examined involving pyrimido[4,5-b][l,4]oxazine (8-oxapteridine) derivatives. It is anticipated that these compounds might interfere with the essential intermediary metabolic functions of the vitamin and thus serve as potential chemotherapeutic agents. Preliminary toxicity studies in microbial assay systems were disappointing; however, inhibitory effects were demonstrated in cell free enzyme systems… more
Date: December 1974
Creator: Lin, Shwu-Ching H.
Item Type: Refine your search to only Thesis or Dissertation
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Long-Range Carbon-13--Carbon-13 Spin-Spin Coupling Constants

Description: The study consists of three major areas of research. First, the dihedral angle dependence of vicinal carbon-carbon coupling constants is determined for aliphatic and alicyclic carboxylic acids wherein the formal hybridization and substituents are held constant. Second, the magnitudes and relative signs of long-range carbon-carbon coupling constants in a. triple- 13 C-labeled system are determined and compared with carbon-proton and/or proton-proton coupling constants in geometrically similar co… more
Date: December 1974
Creator: Miller, Denis E.
Item Type: Refine your search to only Thesis or Dissertation
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