Physical Sciences and Mathematics Commons^™

High Performance Liquid Chromatographic Determination Of Thromboxane B2 In Human Serum As A Methoxime-Panacyl Ester Derivative, Robert H. Pullen

Masters Theses

No abstract provided.

The Synthesis And Evaluation Of The Cardiovascular Activity Of Novel Imidazole Ring Systems, Joseph E. De Los Angeles

Chemistry & Biochemistry Theses & Dissertations

An investigation was undertaken to synthesize and evaluate the cardiovascular activity of two imidazole ring systems. Imidazoles with hypotensive activity would provide novel potential antihypertensive drugs. These novel structures may also find use as chemical probes in the study of the cardiovascular system and as prototypes for other potential cardiovascular agents.

The histamine derivative, 7,7-dipyridyl-4,5,6,7-tetrahydroimidazo-[4,5-c]pyridine (ligand l), was demonstrated to possess significant hypotensive activity in laboratory rats. A 15 mg/Kg dose of ligand 1 produces a statistically significant decrease in blood pressure when injected IP. This hypotensive effect is also associated with marked increase in heart rate. Although compound 1 …

Reactive Counterion Surfactant Catalysis Of Hydroxamic Acid Hydrolysis With Perfluorooctanoic Acid, Mohamed El-Sayed Ayoub

Masters Theses

A micellar effect upon the rate of hydrolysis of hydroxamic acids in aqueous perfluorooctanoic acid has been demonstrated for hydroxamic acids with chain lengths of six , eight, and ten carbons. In this system the counterion, hydrogenion, is a catalyst. Typical rate constant-surfactant concentration profiles for micellar catalysis were obtained. The results for these hydrolyses are consistent with the pseudo-phase model for micellar effects.

In addition the Arrhenius activation energies were determined for the reaction of octanohydroxamic acid at surfactant concentrations above and below the critical micelle concentration of the surfactant. The activation energy is lower for reaction in the …

The Chemistry Of Novel Chromium(Iv) Systems And Fluorinated Hypochlorites, Joseph Onuorah Udeaja

Dissertations and Theses

Chromium(IV) has been of interest for some time because of its role as an intermediate in chromic oxidation reactions. Since there are not a great number of stable tetravalent chromium complexes known, and the use of such species as oxidizing agents has not been widely explored, the preparation, isolation and characterization of new stable tetravalent chromium species may allow chemists the opportunity to more fully understand the role which tetravalent chromium plays in oxidation reactions. The present study thus involves the synthesis of Cr(OC₄H₉)₄ and other Cr(IV) derivatives and the use of Cr(OC₄H …

Geometric Photoisomer Investigation Of Bilirubin (Z,Z)-Ixα, Robert Howe Walker Iii

Chemistry & Biochemistry Theses & Dissertations

Numerous investigations of bilirubin have been reported in the literature. Correlation among these investigations can not be made because of multiple behavioral changes characteristic of the solubilized pigment. This research was initiated to evaluate bilirubin and its associated isomers in identical chemical environments.

Two different solvent systems were experimentally selected to study chemical behavior of bilirubin and occurring photoisomers. A ternary solution consisting of 1:3:1 chloroform:methanol:water was used exclusively in visible spectrophotometric analyses. Also, a pH 10.00 buffer was utilized. This latter system has successfully been used in spectrophotometric and voltammetric work.

Four different photochemical processes have been detected spectrophotometrically, …

The Synthesis Of Phenyl Carbamate (From Urea, Phenol, And A Lewis Acid), Michael W. Barrett

Honors Theses

The synthesis of phenyl carbamate from urea, phenol, and Lewis acid was attempted with varied results being observed. The proposed reaction mechanism involves and Acyl-2 type reaction with a nucleophilic attack on urea by phenol. The Lewis acid is present to add carbocation character to the urea and to further complex with by-products, thus driving the reaction to completion. The solvents utilized were isopropyl alcohol, dichloromethane, and tetrahydrofuran. The reaction parameters were varied in an effort to successfully run a reaction mechanism. Phenyl carbamate was not isolated and what was observed of the reactions did not appear to follow the …

An Nmr Analysis Of The Hydrolysis Of Alpha-Bromopropionic Acid, Barbara A. Jensen

Honors Theses

The kinetics of hydrolysis of ∝-bromopropionic acid were investigated at 80° and a constant pH of 3.3. An average first order rate constant of 4.74x10-3 min-1 was determined. This hydrolysis reaction has been studied by several workers. It is unique in that the reaction proceeds through inversion reactions, the first involving the carboxylate ion. This paper covers the first study where the pH of the system was maintained constant. The design if an inexpensive pH-stat for this purpose is given. The experiment and/ or data lend themselves useful for treatment in physical chemistry where the students must gather data in …

Saponification Of Several Esters Of Pilvalic Acid, Kevin Thomas Watkins

Honors Theses

The base promoted hydrolysis, saponification, of several esters of pivalic acid (trimethyl acetic acid – C (CH3)3COOH) has been studied. Kinetic studies were performed and a possible mechanism for the reactions is proposed. The saponification of esters has been well studied. Ingold1 proposes three possible mechanisms for the reaction; Bac2, Bal1, and Bal2. The B stands for base promoted, the ac and al for acyl oxygen cleavage or alkyl oxygen cleavage, respectively, and the 1 or 2 for first or second order kinetics.

Luminescence Probes For The Measurement Of Oxygen, Mary Katherine Carroll

Honors Theses

The goal of this project was to design an optical sensor for oxygen. One type of system suitable for oxygen detection in aqueous solutions is based on two distinct emission bands: one band oxygen-sensitive, the other insensitive to oxygen quenching. By taking the ratio of these bands, a quantitative measurement of the oxygen present could be obtained. This could be accomplished in a system where a fluorescing compound, through triplet state energy transfer, causes a lanthanide ion to luminesce. By choosing a compound which has a triplet energy near the excitation wavelength of terbium (III) or europium (III) and which …

The Triplet State Photophysics Of Phenanthrene, Roberta Susnow

Honors Theses

The first excited triplet state (TI state) of aromatic hydrocarbons such as phenanthrene acts as an intermediate in many chemical and photochemical reactions. The TI state is a metastable state and its lifetime can be measured in terms of its decay to the ground state. The duration of this decay is on the order of microseconds. Therefore, techniques for measuring the kinetics of fast reactions must be employed in the determination of the rate of the TI state decay, one such technique that is utilized in this research is flash photolysis. The rate of the Tl state decay is greatly …

Simultaneous Knudsen- And Torsion-Effusion Measurements Of The Vapor Pressures Of Triphenyl Aluminum And Triphenyl Boron, Steven Wayne Govorchin

Masters Theses

The sublimation pressures of triphenyl aluminum and triphenyl boron have been determined from simultaneous measurements of the rate of mass effusion and torsional recoil. For triphenyl aluminum the measured vapor presures are expressed by the equations:

logio (P_k/P°) = (12.76 ± 1.25) - (8214 ± 572) (K/T)

logio (P_t/p °) = (12.83 ± 1.34) - (8206 ± 615) (K/T)

where P_k and P_t are the pressures measured by the Knudsen-effusion and torsional-recoil techniques, respectively, and p° = 101.325 kP_a. For triphenyl boron the measured vapor pressures are expressed by the equations:

log …

Peroxo Complexes Of Vanadium(V) And Molybdenum(Vi) With Nicotine And Aspartic Acids, Sandra Jean Sheffield

Dissertations, Theses, and Masters Projects

No abstract provided.

The Cure Reaction Of An Aromatic Thermosetting Polyimide, Michael Edward Whitham

Dissertations, Theses, and Masters Projects

No abstract provided.

The Synthesis Of Hindered Aliphatic Ketones For The Future Production Of Spiro [4.5] Decane Sesquiterpenes, Stephen Lee Hodges

Dissertations, Theses, and Masters Projects

No abstract provided.

Secondary Isotope Effects Of Nucleophilic Vinylic Substitution, Paul Frederick Drees

Dissertations, Theses, and Masters Projects

No abstract provided.

Use Of Isomerizable N-Alkylmerocyanine Dyes To Robe Molecular Interactions Within Micellar Solubilization Sites, Kim Jason Dennis

University of the Pacific Theses and Dissertations

Effects of aqueous surfactant solutions upon cis/trans isomerization reactions of various N-alkyl-merocyanine dyes (II) were studied. Dramatic rate enhancements were found for all dyes in CTAB and SDS solutions above the CMC. CTAB solutions showed the greatest effect with some dye isomerizations catalyzed in excess of 1000-fold. Increases in either CTAB concentration or dye isomerization rates. N-methyl through N-pentyl dye isomerization rates were measured as a function of CTAB concentration and the data treated according to the pseudophase model for micellar catalysis. K_S values ranged from 198 to 2000 M^-1 for N-methyl to N-pentyl dyes, respectively. Micellar rate …

A Preliminary Study On The Separation Of Bovine Plasma Albumin-Copper Ion Dimer And Trimer Reaction Products By Ion-Exchange Chromatography, James T. Miller

Honors Theses

When bovine plasma albumin is in the presence of copper metal ions at pH values below the isoelectric point, a dimerization reaction takes place between the protein molecules. The kinetics of this reaction have been previously studied by using light scattering techniques. These techniques involve monitoring the amount of light scattered as the dimerization reaction proceeds. As the amount of dimer present increases, more light is scattered due to increased molecular size in the solution. Accurate calculations of the rate of this reaction depend upon knowing the ratio of dimer to monomer concentrations at any given time. Unfortunately, evidence has …

The Synthesis And Characterization Of Some Thermally Stable Polypyrazoles And Acetylene Terminated Aspartimides, John W. Connell

Theses and Dissertations

Reactions involving the nucleophilic addition cyclization to activated acetylenes have been employed as a novel route to moderate to high molecular weight polymers. Polypyrazoles (PI to P12) have been prepared from the Michael-type addition cyclization of various aromatic dihydrazines to aromatic dipropynones in m-cresol. The aromatic dihydrazines employed were 4, 4'-dihydrazinodiphenyl ether (4,4' -DHDPE), 4,4 '-dihydrazinodiphenylmethane (4, 4'-DHDPM), and 4, 4' -dihydrazinodiphenyl sulfone (4,4'-DHDPS). The dipropynone sutilized were 1,1’- (1,4-phenylene) bis (3-phenyl- 2-propyn-l-one), (l,4 -PPPO), 1,1’ - (1, 3-phenylene) bis (3 -phenyl- 2 -propyn-l-one), (1,3-PPPO), 1,1 '-(1,4 -phenylene) bis (2 -propyn- l-one), (1,4 -PPO), and 1,1’- (1,3 -phenylene) bis (2 …

A Study Of Dislocations In Crystals Using The Technique Of Chemical Etching, Ramona R. Dennis

Honors Theses

The beauty of many of the crystalline solids has attracted man's attention from the earliest times. Eventually the science of crystallography developed from studies of their shapes. The word crystal sterns from the Greek word "krystallos" meaning "clear ice." The word was first applied to describe the clear quartz crystals found in the Swiss Alps. The crystals were thought to be formed from water under conditions of extreme cold.

The earliest recorded crystallographic observation was in 1597 by Andreas Libarius. He noticed that crystals of different substances often have characteristic shapes. He suggested that the salts in mineral water could …

Flow Injection And Photometric Determination Of S(Iv) In Rainwater With Pararosaniline, Frank A. Hedgecock

Retrospective Theses and Dissertations

The photometric pararosaniline (pRA) method for determination of S(IV) has been adapted to flow injection sample processing (FIA). Prominent features of the method include a limit of detection of 0.010 ppm of dissolved sulfur dioxide and a sampling rate of 20 per hour. The concentration range investigated was 0.010 to 0.200 ppm S0₂. Sequential samples were collected from two rainstorms and SO₂ concentrations were measured for 19 samples. The suppression of interference by Cr(III), Mn(II), and Fe(III) using 1,2-cyclohexylenedinitrilotetraacetic acid (CDTA) and ethylenediaminetetraacetic acid (EDTA) was investigated. A comparison of the adapted FIA method and its parent …

New Synthetic Applications Of Enaminoketones, Timothy J. Buck

Retrospective Theses and Dissertations

This report discusses research concerning synthetic applications of enaminoketones. The work may be divided into four parts as follows: a) replacement of the dimethylamino group of certain enaminones by other amine groups through a simple procedure; b) formation of 3-alkyl-pyrazoles; c) formation of 2-amino-4-alkyl-pyrimidines; d) synthesis and subsequent reduction of iminium salts. The starting materials (E-1-(N,N-dimethylamino)-1-alkene-3-ones) have been condensed with hydrazine and guanidine to form pyrazoles and pyrimidines, respectively. The same starting materials have been reacted with POCl₃ in CH₂Cl₂ to produce chlorovinyliminium salts. These have then been reacted in situ with reducing agents to produce …

Synthesis Of Phosphine Trans-Substituted Derivatives Of Iron Pentacarbonyl, Karl Heinz Hecker

Masters Theses

The synthesis of trans-Fe (CO)₃(PR₃)₂ (PR₃ = PPh₃, PPh₂Me, PPh₂CHCH₂, P(c-C₆H₁₁)₃, P(n-C₄H₉)₃, PPh₂H) can be achieved by refluxing iron pentacarbonyl under reducing conditions in the presence of ligand in 1-butanol. Addition of iron pentacarbonyl to a 1-butanol solution of sodium borohydride at room temperature results in a quantitative conversion of the iron carbonyl complex to the corresponding mononuclear formyl complex. Upon heating the initially formed formyl species decomposes to form the …

The Stereospecific Synthesis Of Tetrahydropyrans And Tetrahydrofurans, Rhonda Carol Winstead

Dissertations, Theses, and Masters Projects

No abstract provided.

Peroxo Complexes Of Molybdenum (Vi) And Vanadium (V) With Imidazole And Histidine, Jennifer Lisa Gundersen

Dissertations, Theses, and Masters Projects

No abstract provided.

Ion Selective Electrodes Based On Aza- Substituted Crown Ethers, Lisa Ann Wellington

Retrospective Theses and Dissertations

A cation-responsive electrode system has been developed which incorporates aza-substituted crown ethers as ligands. In a novel application, uncomplexed crown ethers were used in the pelletized form for ionic transport. Electrodes have been produced which can be conditioned for a particular ion and following their use, be reconditioned and reused for other ions. Preparation method and lifetime studies are included.

The responses of two crown ethers with plasticizers were evaluated for thirteen representative cations. The concentration range covered in each evaluation was 1 x 10^-1 to 1 x 10^-7 M. For those ions exhibiting Nernstian or near-Nernstian response, …

The Use Of Scheffe-Equivalent Equations To Predict Physical Properties Of Neoprene, Cheng Y. Loh

Retrospective Theses and Dissertations

The goal of this study is to find a more organized and directed approach to build models for mixture systems. An attempt is made to generate and then compare Scheffe (mixture) models with those generated by McGee using the ‘conventional’ method for neoprene data. The models are judged on their ability to predict physical properties of neoprene by comparing the following: predicted and actual values by inspection; the calculated % error of prediction; the squared multiple correlation coefficients; adjusted squared multiple correlation coefficients; the Fisher statistic and significance probability. Scheffe models do not have an intercept term and test statistics …

Electrochemical Studies Of Transition Metal Carbonyls, Dwayne Edward Cooper

Masters Theses

The electrochemical oxidation of (OC)₅MP-PM'(CO)₅ (M=Cr, Mo, W; M'=Cr, Mo, W; M=M' or M≠M'; P-P=Ph₂PCH₂CH₂PPh₂) and the reduction of the oxidized products in a 0.1 M tetrabutyl-ammonium perchlorate methylene chloride solution at a platinum disc working electrode with a Ag/AgCl reference electrode have been studied. The number of electrons in the oxidation step was determined by comparison with the one electron oxidation of ferrocene which had a peak potential at +0.15 V.

The cyclic voltammograms of the homobimetallic and heterobimetallic complexes display two general chacteristics: quasi-reversible or irreversible one …

Characterization Of The Capsular Polysaccharides On Cell Membranes Of Rhizobium Trifolii And Three Of Its Nod- Mutants, Jesse Ardosa

Masters Theses

The ever-present specter of the inavailability of food production to increase in direct proportion to population growth haunts practically every nation of the world. As more and more tracts of land are incorporated to accommodate expanding cities, they become less available for food production. Emphasis, therefore, is placed on obtaining a higher yield per acreage planted. Since fertilization is not reliable in the long term due to an eventual depletion of raw materials for fertilizers, the ability of plants like legumes to assimilate free soil nitrogen on their own has become increasingly important [1,11,14,17]. However, the mechanisms involved are still …

Syntheses And Electrochemistry Of Monosubstituted Carbonyl Complexes Of Low Valent Ruthenium, Nor Azowa Ibrahim

Masters Theses

The reactions of Ph₂MeP and PhMe₂P with (PPh₃)₄RuCl₂ yield (PPh₂Me)₄RuCl₂ and (PPhMe₂)₄RuCl₂, respectively. These complexes have been shown by conductivity studies to be dissociated in acetonitrile and exist as [(PPh₂Me)₄RuCl(CH₃CN)]Cl and [(PPhMe₂)₄RuCl(CH₃CN)]Cl. When carbon monoxide was bubbled into these solutions, monocarbonyl complexes were obtained. Elemental analyses, ¹H NMR, ³¹P NMR, infrared spectroscopy, conductivity measurements, and polarography were used to analyse the products, (PPh₂Me)_{2 …}

Enhancement Of Ether Cleaving Reactions By Intramolecular Hydrogen Bonding, Nobumi Takemura

Masters Theses

Rate constants of cleavages of fourteen alkyl-aryl ethers with HI, KI, or LiI in pyridine at 50-150°C were determined under pseudo first order conditions. The following ethers which have a six-membered ring intramolecular hydrogen bond underwent a bimolecular nucleophilic displacement by iodide ion in pyridine: 8-methoxy-1-naphthalenol, 8-ethoxy-1-naphthalenol, 2-methoxybenzoic acid, and 2-hydroxybenzyl methyl ether. The following ethers which lack a six-membered ring hydrogen bond were not cleaved or underwent cleavage slowly compared with the hydrogen bonded compounds: 1,8-dimethoxynaphthalene, 1,8-diethoxynaphthalene, 1-methoxynaphthalene, 4-methoxybenzoic acid, methyl 2-methoxybenzoate, 2-methoxybenzyl methyl ether, and 4-methoxybenzyl methyl ether. The pattern of ether reactivity indicated that a six-membered ring …