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Imide/Arylene Ether Copolymers, Brian J. Jensen Jan 1990

Imide/Arylene Ether Copolymers, Brian J. Jensen

Theses and Dissertations

Three different series of imide/arylene ether block copolymers were prepared using two different imide blocks and two different arylene ether blocks. Block molecular weights studied were 3110 and 6545 g/mole for each block and all four combinations possible were prepared in each series. Also, several segmented copolymers were prepared by forming the imide segment and the copolymer in the presence of the pre-formed arylene ether block.

Two amine-terminated poly(arylene ether) blocks (ATPAE) were prepared by reacting 1,3-bis(4-fluorobenzoyl)benzene with either 2,2-bis(4-hydroxyphenyl)propane (BPA) or 9,9-bis(4-hydroxyphenyl)fluorene (BPF) and 4-aminophenol. Two anhydride-terminated poly(amic acid) blocks were prepared by reacting 4,4'-oxydianiline (ODA) or 1,3-bis(4-aminophenoxy-4’- benzoyl)benzene …


The Effects Of Crosslinking On The Stability And Autoxidation Rate Of Human Hemoglobin A, Thao Yang Jan 1990

The Effects Of Crosslinking On The Stability And Autoxidation Rate Of Human Hemoglobin A, Thao Yang

Dissertations

No abstract provided.


Palladium (Ii) Catalyzed Oxidation, Isomerization And Exchange Of Olefins Allylic Alcohols And Allylic Ethers In Water And Methanol Solvents, John Wayne Francis Jan 1990

Palladium (Ii) Catalyzed Oxidation, Isomerization And Exchange Of Olefins Allylic Alcohols And Allylic Ethers In Water And Methanol Solvents, John Wayne Francis

Dissertations

No abstract provided.


Multinuclear Magnetic Resonance Studies Of Arenesulfonates: Substituent, Concentration, Counterion, And Solvent Effects, David C. French Jan 1990

Multinuclear Magnetic Resonance Studies Of Arenesulfonates: Substituent, Concentration, Counterion, And Solvent Effects, David C. French

Dissertations

No abstract provided.


Dementia In Stroke Survivors In The Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, And Computed Tomographic Findings, Thomas K. Tatemichi, Mary A. Foulkes, J. P. Mohr, Jeffrey R. Hewitt, Daniel B. Hier, Thomas R. Price, Philip A. Wolf Jan 1990

Dementia In Stroke Survivors In The Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, And Computed Tomographic Findings, Thomas K. Tatemichi, Mary A. Foulkes, J. P. Mohr, Jeffrey R. Hewitt, Daniel B. Hier, Thomas R. Price, Philip A. Wolf

Chemistry Faculty Research & Creative Works

We Determined the Prevalence of Dementia in 927 Patients with Acute Ischemic Stroke Aged ≥60 Years in the Stroke Data Bank Cohort based on the Examining Neurologist's Best Judgment Diagnostic Agreement among Examiners Was 68% (K=0.34). of 726 Testable Patients, 116 (16%) Were Demented. Prevalence of Dementia Was Related to Age But Not to Sex, Race, Handedness, Educational Level, or Employment Status Before the Stroke. Previous Stroke and Previous Myocardial Infarction Were Related to Prevalence of Dementia Although Hypertension, Diabetes Mellitus, Atrial Fibrillation, and Previous Use of Antithrombotic Drugs Were Not Prevalence of Dementia Was Most Frequent in Patients with …


Biological Activity And Conformational Analysis Of Nikkomycins And Their Analogs, Eduardo Krainer Jan 1990

Biological Activity And Conformational Analysis Of Nikkomycins And Their Analogs, Eduardo Krainer

Dissertations, Theses, and Capstone Projects

Nikkomycins and polyoxins are peptidyl nucleoside antibiotics produced by Streptomyces species. They are potent inhibitors of chitin synthetases from pathogenic fungi, and polyoxins have been used in Japan for many years as agricultural fungicides and for insect control. Since chitin synthetase is not found in mammals and both families of antibiotics are not toxic, these inhibitors are potentially attractive for clinical use. Unfortunately these compounds seem to have only a fungistatic action, and they are not used clinically at present.

A procedure for efficiently obtaining nikkomycins X and Z of very high purity from crude antibiotic is described. These nikkomycins …


Evaluation Of A Remote Sensor For Mobile Source Co Emissions, Donald H. Stedman, Gary A. Bishop Jan 1990

Evaluation Of A Remote Sensor For Mobile Source Co Emissions, Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

Final Report to U. S. Environmental Protection Agency,


Automobile Testing In The Toronto Area, Donald H. Stedman, Gary A. Bishop Jan 1990

Automobile Testing In The Toronto Area, Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


A Study Of The Hydration Properties Of Selected Laser Dye Aerosols Including Continuous-Flow Parallel Plate And Alternating-Gradient Thermal Diffusion Cloud Chamber Measurements In The High Supersaturation Regime, Donald E. Hagen, Max B. Trueblood, Darryl J. Alofs Jan 1990

A Study Of The Hydration Properties Of Selected Laser Dye Aerosols Including Continuous-Flow Parallel Plate And Alternating-Gradient Thermal Diffusion Cloud Chamber Measurements In The High Supersaturation Regime, Donald E. Hagen, Max B. Trueblood, Darryl J. Alofs

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Hydration Behavior of Aerosols made Up of Various Fluorescent Dyes when Exposed to Water Saturation or Supersaturated Conditions Has Been Studied. Critical Supersaturation Spectra Are Reported. the Dyes Are Found to Behave as High Molecular Weight Ionic Compounds that Obey Kohler Theory. their Relevant Kohler Parameters Are Measured. This Study Makes Use of and Compares Results from the Isothermal Hazecontinuous-Flowand Alternating-Gradient Thermal Diffusion Cloud Chambers. the Ability of the Continuous-Flow Thermal Diffusion Chamber to Operate Correctly at High Supersaturations is Shown. © 1990 Elsevier Science Publishing Co., Inc.


Insecticides Based On Differences In Metabolic Pathways, Richard T. Mayer, G N. Cunningham, John T. Gupton Jan 1990

Insecticides Based On Differences In Metabolic Pathways, Richard T. Mayer, G N. Cunningham, John T. Gupton

Chemistry Faculty Publications

Insects have been major pests of humankind at least since the beginning of recorded history. To this day insects continue to cause problems in domestic, agricultural, and health situations. It is no wonder that people have continually sought new solutions to controlling insect pests. Even when new control methods are discovered and established, insects evolve into resistant species so that the method is only of real value for a few brief years. Modern science and technology are now enabling scientists to tear away the fabric that has so long masked physiological and biochemical events critical to insects. Armed with this …


Sans From Tetradecylpyridinium Bromide Based Microemulsions, Paul M. Lindemuth, Boualem Hammouda, Raymond L. Venable Jan 1990

Sans From Tetradecylpyridinium Bromide Based Microemulsions, Paul M. Lindemuth, Boualem Hammouda, Raymond L. Venable

Chemistry Faculty Research & Creative Works

Small-angle neutron scattering is used to investigate tetradecyl pyridinium bromide/pentanol/heptane/heavy water microemulsions in the water-in-oil (W/O) microemulsion phase diagram region. The heavy water content is increased while the other components (surfactant, cosurfactant, hydrocarbon) are kept constant. With use of a simple model assuming spherical micelles interacting with a hard-sphere potential (Percus-Yevick model), aggregate sizes and packing fractions have been extracted and found to agree with values determined from the mixing conditions. These experiments clearly show the transition from the single-particle (heavy water + Stern layer droplet) scattering regime at low water concentration to the mixed single/interdroplet scattering regime when the …


Relevance Of Enantiomeric Separations In Food And Beverage Analyses, Daniel W. Armstrong, Chau Dung Chang, Wei Yong Li Jan 1990

Relevance Of Enantiomeric Separations In Food And Beverage Analyses, Daniel W. Armstrong, Chau Dung Chang, Wei Yong Li

Chemistry Faculty Research & Creative Works

A series of new derivatized cyclodextrins have been developed for use as chiral stationary phases in capillary gas chromatography. As a result, a large number of the enantiomeric components in food and beverage products can be resolved relatively quickly and easily. The study focuses on compounds other than amino acids (e.g., malic acid, lactic acid, tartaric acid, esters, alcohols, lactone flavors or fragrances, and so on). The ability to separate and quantitate enantiomers at low levels should be useful for detecting adulterated products, for evaluating fermentation processes, and for the accurate characterization of enantiomeric flavor components, growth regulators, pesticides, and …


4-(Phenylsulfonyl) Butanoic Acid: Preparation, Dianion Generation, And Application To Four Carbon Chain Extension ; Studies Of Organophosphorus Compounds Derived From Serine, Jeffrey A. Frick Jan 1990

4-(Phenylsulfonyl) Butanoic Acid: Preparation, Dianion Generation, And Application To Four Carbon Chain Extension ; Studies Of Organophosphorus Compounds Derived From Serine, Jeffrey A. Frick

Dissertations

No abstract provided.


Molecular Mobility In A Model Polymer Composite, Joan Ethel Gambogi Jan 1990

Molecular Mobility In A Model Polymer Composite, Joan Ethel Gambogi

Masters Theses

"The adsorption of aminoalkysilane coupling agents onto silica surfaces and the interaction of these functional silanes with a bismaleimide and an epoxy resin has been studied using solid-state NMR techniques. 13C CP-MAS was used to confirm the bonding between the silence and bismaleimide (BMI) resin and elucidate the nature of the crosslinking reaction of BMI. Deuterated coupling agents were synthesized and adsorbed on silica surfaces. The motional dynamics were probed using deuterium solid-echo NMR. It was determined that the motion of the alky portion of the coupling agents was consistent with gauche migrations (gtt ↔ tig) and pair gauche …


Substituent Effects On The Stereochemistry Of 1,3-Dipolar Cycloadditions To 7-Substituted Norbornadienes, Ramakrishnan Subramanian Jan 1990

Substituent Effects On The Stereochemistry Of 1,3-Dipolar Cycloadditions To 7-Substituted Norbornadienes, Ramakrishnan Subramanian

Dissertations

No abstract provided.


¹⁷O And ³³S Nuclear Magnetic Resonance Studies Of Some Selected Sulfonates: Concentration And Solvent Dependence, Telitha M. Murray Jan 1990

¹⁷O And ³³S Nuclear Magnetic Resonance Studies Of Some Selected Sulfonates: Concentration And Solvent Dependence, Telitha M. Murray

Dissertations

No abstract provided.


Air Oxidation Of A Soluble Coal Extract, Douglas Kimbler Dec 1989

Air Oxidation Of A Soluble Coal Extract, Douglas Kimbler

Masters Theses & Specialist Projects

The effects of air oxidation on coal may change many important attributes of the coal such as calorific values, solubilities and solvent swelling values. By studying the effects of air oxidation on the soluble portion of coal, we were able to study coal oxidation in a new light.


Ua66/7/2 Hilltopper News, Wku Chemistry Oct 1989

Ua66/7/2 Hilltopper News, Wku Chemistry

WKU Administration Documents

Newsletter created by and about the WKU Chemistry department.


Identification And Quantitation Of Volatile Amines In Marine Sediments, Chuen Mei Huang Oct 1989

Identification And Quantitation Of Volatile Amines In Marine Sediments, Chuen Mei Huang

Chemistry & Biochemistry Theses & Dissertations

Pore waters which were taken from sediments of the Chesapeake Bay were analyzed to determine the presence of volatile amines. A purge-and-trap technique was used to concentrate the amines. Then, following derivatization with heptaflourobutyric anhydride, the HFBA-amines were analyzed by gas chromatography with electron capture detection and with mass spectrometric detection. One secondary amine, diethylamine with a concentration of 0.3-0.6 uM, was found in a total of three pore water samples from cores collected on two different dates. A primary amine, sec-butylamine with a concentration of O. 05 AIM, was also found in one of these same samples. Another primary …


Study Of Acetone Extractable Organic Matter From Airborne Particulate Matter From An Urban Site, Wenhui Wu Sep 1989

Study Of Acetone Extractable Organic Matter From Airborne Particulate Matter From An Urban Site, Wenhui Wu

Theses

Two seasonal periods (Winter 1988; Summer 1988) of daily Newark urban air samples were collected on glass fiber filters. Each filter was first extracted with dichloromethane and subsequently with acetone. Quarterly composites of each were then tested for mutagenicity. The results of the analysis of the less polar dichloromethane extracts were reported in the thesis of Junghen Lwo. A modified fractionation scheme involving acid-base partitioning and silica gel column chromatography has been used as the first step in the bioassay-directed search for significant levels of mutagenic compounds in extracts of inhalable (IP 10) ambient air particulates. The biologically "hot" fractions …


Semiempirical Determination Of Intermolecular Anharmonicity In Molecular Crystals: The Case Of 1,2,4,5-Tetrabromobenzene, R.C. Dye, Craig J. Eckhardt Sep 1989

Semiempirical Determination Of Intermolecular Anharmonicity In Molecular Crystals: The Case Of 1,2,4,5-Tetrabromobenzene, R.C. Dye, Craig J. Eckhardt

Craig J. Eckhardt Publications

The molecular crystal 1,2,4,5-tetrabromobenzene (TBB) has been studied using Brillouin scattering and lattice dynamical calculations. A method for mapping acoustic mode anharmonicity is developed that exhibits substantial directional behavior and correlates well with the directions of the molecular movements associated with the phase transition. It is shown that by comparing the calculated sound velocities with the experimental values, insight can be gained into the displacive phase transition and the lattice dynamics of TBB. The sound velocities are plotted for three crystallographic planes containing the crystal axes. The relationships between sound velocities and lattice dynamics are discussed. The phonon dispersion curves …


Uv Multiphoton Induced Chemistry Of Nitrobenzene In Solution, Joseph J. Belbruno, Gary Siuzdak, Simon North Sep 1989

Uv Multiphoton Induced Chemistry Of Nitrobenzene In Solution, Joseph J. Belbruno, Gary Siuzdak, Simon North

Dartmouth Scholarship

The technique of Multiphoton Induced Chemistry (MPIC) has been employed to initiate ion-molecule chemistry of organic molecules in solution. We report one of the first examples of the use of liquid phase multiphoton ionization (MPI) to prepare organic cations, which then react with the solvent in ionmolecule processes. The products obtained in this chemical sequence are significantly different from those observed in conventional or multiphoton-induced neutral chemistry in the same solvent. The particular example explored in this work is the reactivity of the nitrobenzene cation in methanol solvent. Products of the ion-molecule chemistry, detected by gas chromatography/mass spectrometry, are phenol …


Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak Aug 1989

Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

The theory for measuring ligand binding constants from footprinting autoradiographic data associated with a single binding site is derived. If the ligand and DNA cleavage agent compete for a common site, the spot intensities are not proportional to the amount of DNA not blocked by ligand. The analysis of a single site is experimentally illustrated by using results for the anticancer drug actinomycin D interacting with the duplex d(TAGCGCTA)2 as probed with the hydrolytic enzyme DNase I.


Photocycloaddition Of 4,5',8-Trimethylpsoralen And Oleic Acid Methyl Ester: Product Structures And Reaction Mechanism, Kathleen G. Specht, W. Robert Midden, Miles R. Chedekel Aug 1989

Photocycloaddition Of 4,5',8-Trimethylpsoralen And Oleic Acid Methyl Ester: Product Structures And Reaction Mechanism, Kathleen G. Specht, W. Robert Midden, Miles R. Chedekel

Chemistry Faculty Publications

The stereochemical structures of the four adducts formed between oleic acid methyl ester (OAME) and 4,5',8-trimethylpsoralen (tmPso) have been determined. Assignment of the tmPso 'H NMR spectrum was accomplished by analogy to two coumarin model compounds and with the use of homonuclear decoupling and resonance enhancement. Assignment of the lH NMR spectra for the OAME-tmPso adducts was made by analogy to the spectra of OAME and tmPso and using 2D &resolved and COSY analyses. The configurations of the cyclobutyl rings in these adducts was determined by The stereochemical structures of the four adducts formed between oleic acid methyl ester (OAME) …


Thermogravimetric Analysis Of Coal Blends Under Conditions Of Pyrolysis & Combustion, Yaodong Gan Aug 1989

Thermogravimetric Analysis Of Coal Blends Under Conditions Of Pyrolysis & Combustion, Yaodong Gan

Masters Theses & Specialist Projects

In recent years, the growing attention to coal quality by coal-burning utilities has led to an increase in coal blending. Coal blending is done with both economics and the quality of coal in mind. To assess the quality of coal, pyrolysis and combustion influencing thermal parameters, as measured in thermogravimetric analysis (TGA) experiments can be applied. The coal industry needs a study to determine relationships that may exist between the measured values of TGA thermal parameters in individual coals and those in the blends. The TGA thermal parameters are the weight loss, Tmax, Ti, T1/2 …


Light Scattering Apparatus For Angular Dependent Studies Of Anisotropic Materials, R.C. Dye, J. Sartwell, Craig J. Eckhardt Aug 1989

Light Scattering Apparatus For Angular Dependent Studies Of Anisotropic Materials, R.C. Dye, J. Sartwell, Craig J. Eckhardt

Craig J. Eckhardt Publications

An improved method for light scattering from acoustic phonons in small, low-symmetry solids is described. This instrumentation greatly facilitates the determination of elastic constants in highly anisotropic materials. Elastic scattering can be greatly reduced so that weaker phonon modes can be observed. Errors associated with the determination of the polarization directions of an anisotropic material are minimized by considering crystal optics. Review of Scientific Instruments is copyrighted by The American Institute of Physics.


31st Rocky Mountain Conference Jul 1989

31st Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and registration information for the 31st annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, July 30 - August 4, 1989.


A Study Of The Flammability Of Chlorinated Polyethylene By Thermal Analysis, Michele Whitely Jul 1989

A Study Of The Flammability Of Chlorinated Polyethylene By Thermal Analysis, Michele Whitely

Masters Theses & Specialist Projects

High Density Polyethylene (HDPE) is a highly flammable compound. Finding a method to reduce HDPE's flammability is of great scientific interest to researchers and industry. Chlorination of the HDPE has been shown to have an effect on the flammability of the polymer. This study looks at the effects of various chlorinated samples on the thermal decomposition of HDPE in atmospheres of nitrogen, air, and oxygen. The thermal analysis instruments used were a Thermogravimetric Analyzer (TGA), and a Differential Scanning Calorimeter (DSC). To study the gaseous products evolved during thermal decomposition of the polymer Fourier Transform Infrared Spectrophotometry (FTIR) and Gas …


Mounting Sex Pheromone: A Novel Pheromone Responsible For Mate Recognition In The Ixodidae, Jgc Hamilton Jul 1989

Mounting Sex Pheromone: A Novel Pheromone Responsible For Mate Recognition In The Ixodidae, Jgc Hamilton

Theses and Dissertations in Biomedical Sciences

Cholesterol oleate was demonstrated to be the cuticular contact sex pheromone of Dermacentor variabilis. This pheromone which has been termed the Mounting Sex Pheromone (MSP) was also demonstrated to be present on the surface of D. andersoni, Amblyomma maculatum and A. americanum. This contact sex pheromone enables males excited and attracted by 2,6-dichlorophenol to identify the female as a potential mating partner. The MSP is the second in the series of three sex pheromones guiding the hierarchy of behavioral responses which constitute tick courtship behavior. Tests with D. variabilis and D. andersoni showed that this pheromone …


Simultaneous Determination Of 3-Methoxy-4-Hydroxyphenyl-Glycol, Homovanillic Acid, And 5-Hydroxyindoleacetic Acid In Plasma By High Performance Liquid Chromatography, Yung-Te Tseng Jul 1989

Simultaneous Determination Of 3-Methoxy-4-Hydroxyphenyl-Glycol, Homovanillic Acid, And 5-Hydroxyindoleacetic Acid In Plasma By High Performance Liquid Chromatography, Yung-Te Tseng

Chemistry & Biochemistry Theses & Dissertations

A rapid, reliable, and sensitive method for simultaneous determination of 3-methoxy-4-hydroxyphenylglycol (MHPG), Homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5- HIAA) in plasma is described. The method is based on high performance liquid chromatography with electrochemical detection. Samples were filtered with Amicon Centrifree micropartition systems and extracted with organic solvent before chromatography. Chromatographic separation of sample components was achieved isocratically in a C18 reverse-phase column. Quantitation was performed by measuring the peak height ratios of the sample components to an internal standard. Analytical recoveries ranged from 50.78 (SD 4.2%) to 67.94 (SD 3.28). Within-run coefficient of variations (CVs) ranged from 3.78 …