UNT Theses and Dissertations - 203 Matching Results

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The Preparation of Pyridinium Derivatives by the Knoevenagel Condensation

Description: An attempt is made in the work described in this paper to extend the series started by Hall and Platas by means of a Knoevenagel condensation between 3-hydroxy-1,4-naphtho-quinone-2-(4-methylpyridinium) anhydride and various aromatic aldehydes giving rise to a series of unsaturated substituents on the four position of the pyridine ring.
Date: May 1955
Creator: Miller, Eugene James
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The Synthesis of Benzo(d)pyrido(a)-benzimidazole-5,12-quinone

Description: The present investigation yielded an orange product upon refluxing 2-butyramido-3-chloro-1,4-naphthoquinone and 2-aminopyridine in ethanol. When this material was purified, by recrystallization from glacial acetic acid, the melting point was 306 [degrees]. This compound has been shown to be benzo(d)pyrido(a)-benzimidazole-5,12-quinone by the present investigation.
Date: May 1955
Creator: Cooper, James Erwin
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Metal Complexes of 2,3-Quinoxalinedithiol

Description: A series of new planar complexes with the dianion of 2,3-quinoxalinedithiol ligand has been prepared. The complexes have been characterized from the study of their analyses, magnetic moment, conductance, polarograms, electron spin resonance spectra, and electronic spectra, and compared with the available data on the corresponding maleonitriledithiolene and toluene-3,4-dithiolene complexes.
Date: May 1969
Creator: Ganguli, Kalyan Kumar, 1912-
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Kinetic Studies and Vibrational Spectra of Disubstituted Metal Carbonyls

Description: The oxidative elimination reactions of (5-X-phen)Mo(C0)₄ (X = H, CH₃, Cl, NO₂; phen = o-phenanthroline) and (3,4,7,8-(CH₃)₄-phen)Mo(CO)₄ with mercuric chloride in acetone have been investigated. In these reactions, a carbon monoxide group is replaced by two univalent ligands, accompanied by the corresponding increase in coordination number and formal oxidation state of the central metal atom, to give products of the type, (X-phen)Mo(CO)₃(Cl)HgCl. With the exception of (3,4,7,8-(CH₃)₄-phen), the… more
Date: May 1972
Creator: Jernigan, Robert Thorne
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Magnetic Properties of Oxovanadium(IV) Complexes of Substituted N-(Hydroxylalkyl) Salicylideneimines

Description: A series of oxovanadium(IV) complexes of Schiff bases derived from substituted salicylaldehyde and aminoalcohols has been prepared and characterized. The Schiff bases coordinate through 0, N, and 0 as tridentate bivalent ligands. The primary purpose of the investigation is to describe the structure and bonding in these complexes. The subnormal magnetic properties of the complexes provide much information about both the structure and the bonding in the complexes.
Date: May 1972
Creator: Carey, Elbert Franklin
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Experimental and Theoretical Study of Electronic Transitions in Phosphorus, Phosphoryl, and Thiophosphoryl Trichlorofluorides

Description: This thesis is an investigation of the vacuum uv spectra of the phosphorus, phosphoryl, and thiophosphoryl trichlorofluorides in the region 1250 to 3000A. Assignments for absorption bands are made utilizing results from photoelectron spectra and ab initio calculations, oscillator strengths for absorption bands, and CNDO/2 molecular orbital calculations. Results from CNDO/2 calculations are compared with theoretical calculations, and experimental data are discussed with regard to the bonding in … more
Date: May 1973
Creator: McAdams, Mary Jane
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Halogenated 2-Oxetanones

Description: The purpose of this investigation is threefold: (1) to examine in detail the cycloaddition of halogenated ketenes and carbonyl compounds, (2) to study the decarboxylation of the resulting halogenated 2-oxetanones,and (3) to investigate the effect of halogens in the halogenated 2-oxetanones on the nucleophilic addition reaction.
Date: May 1973
Creator: Patel, Arvind D.
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Studies Concerning the Production of Lactobacillic Acid in Lactobacillus Plantarum

Description: This study is concerned with certain factors affecting the content of lactobacillic acid in Lactobacillus plantarum. Three main areas of investigation are reported herein. The effects of both the oxygen tension and the pH of the culture medium on the accumulation of lactobacillic acid were determined. In addition, monolayer studies were conducted to determine the influence of cyclopropane fatty acid content on the molecular packing of membrane lipids.
Date: May 1973
Creator: Halper, Laura Ann
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Isozymes and In Vivo Activity of Triosephosphate Isomerase

Description: The distribution of isozymes of triosephosphate isomerase was normal in all human tissues examined. This finding argues against the existence of tissue-specific isozymes. Normal distributions of isozymes were also found in patients with cri-du-chat syndrome. Thus it is unlikely that a gene for triosephosphate isomerase is located on the short arm of chromosome five in man. When triosephosphate isomerases from a wide range of species were examined by starch gel electrophoresis, definite evolutio… more
Date: May 1974
Creator: Snapka, Robert Morris
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Studies Concerning Asparagine Metabolism in Lactobacillus plantarum

Description: This study is concerned with the metabolism of L-asparagine in Lactobacillus plantarum (ATCC 8014). Theprimary area of investigation is the preliminary characterization of a previously unreported L-asparaginase enzyme in L. plantarum. This L-asparaginase was determined to be an inducible enzyme with variations in its activity level according to the L-asparagine level in the growth medium. L-Glutaminase could not be induced in this organism by L-glutamine, nor would L-glutamine induce the aspar… more
Date: May 1974
Creator: McCue, Bette Ann
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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.
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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
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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
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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
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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.
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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
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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
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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.
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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
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