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Articles 32971 - 33000 of 34528
Full-Text Articles in Physical Sciences and Mathematics
Ua66/7/2 Newsletter, Wku Chemistry
Ua66/7/2 Newsletter, Wku Chemistry
WKU Archives Records
Newsletter created by and about the WKU Chemistry department.
Synthesis And Proof Of Structure Of 2, 2-Dichloro-7h-Cyclobut-(A)-Indian-1-One: A New Route To 4, 5-Benztropolone, Thomas Renwick Potts
Synthesis And Proof Of Structure Of 2, 2-Dichloro-7h-Cyclobut-(A)-Indian-1-One: A New Route To 4, 5-Benztropolone, Thomas Renwick Potts
Masters Theses
No abstract provided.
A Kinetic Study Pertaining To The Enzymatic Reduction Of Pyruvate By Lactate Dehydrogenase, Ronald Floyd Tienhaara
A Kinetic Study Pertaining To The Enzymatic Reduction Of Pyruvate By Lactate Dehydrogenase, Ronald Floyd Tienhaara
All Master's Theses
The reduction of pyruvate as catalyzed by lactate dehydrogenase has been studied by monitoring the oxidation of DPNH (diphosphopyridine nucleotide) at 340 nm. The kinetic investigation was carried out in phosphate buffer at 25° C. Since pyruvate exists in equilibrium with the enolized and hydrated forms, a kinetic analysis was devised to determine the nature of the true substrate for the enzymatic process. Also, a comparative study was made involving two isozymes of lactate dehydrogenase. The catalytic effectiveness of these isozymes was studied as a function of pH and substrate concentration.
Mössbauer-Effect Studies Of The Phase Transitions In Antiferroelectric Pbzro₃ And Ferroelectric Pbti₀.₀₂Zr₀.₈O₃, James P. Canner, C. M. Yagnik, Robert Gerson, William Joseph James
Mössbauer-Effect Studies Of The Phase Transitions In Antiferroelectric Pbzro₃ And Ferroelectric Pbti₀.₀₂Zr₀.₈O₃, James P. Canner, C. M. Yagnik, Robert Gerson, William Joseph James
Physics Faculty Research & Creative Works
The Mössbauer spectra were studied for the antiferroelectric compound PbZrO3 and for the closely related ferroelectric PbTi0.2Zr0.8O3. In both cases, a substitution of 5-mol% BiFeO3 was made to permit the Mössbauer measurements. Little difference was found in the isomer shift in these compounds, whether they were in the ferroelectric, antiferroelectric, or cubic state, indicating that the bonding character is not affected by the transitions among the states. There was a pronounced and approximately equivalent dip in the recoil-free fraction at the Curie points of both the antiferroelectric and ferroelectric materials, associated with …
The Reduction Of Carbonyl Compounds By Sodium Naphthalenide, James Stinnett
The Reduction Of Carbonyl Compounds By Sodium Naphthalenide, James Stinnett
Masters Theses & Specialist Projects
The purpose of this investigation was to study the reactions of sodium naphthaienide with various aromatic carbonyl compounds, particularly aromatic aldehydes and ketones. Although sodium naphthalenide was first investigated in 1936 by Scott et al, the synthetic utility of this alkali metal adduct in organic chemistry has only recently been explored. It was thought that sodium naphthalenide might provide a synthetic advantage, as compared to sodium metal solutions, in the reduction of carbonyl functions to their respective glycols and/or alcohols.
Evidence For The Existence Of Two Stable Sites For Cobalt Impurity Atoms In Aluminum, Arun Venkatachar
Evidence For The Existence Of Two Stable Sites For Cobalt Impurity Atoms In Aluminum, Arun Venkatachar
Dissertations and Theses
Using Fe57Mössbauer spectroscopy, two alternative sites occupied by cobalt (10-4 at. % ) impurity atoms in aluminum have been isolated. The substitutional site A is the stable position after annealing the sample above 840 K, followed by a rapid quench. The impurity atoms in site A are characterized by a single line Mössbauer spectrum (indicative of a cubic environment), a room-temperature f = 0.502 (r. m. s. displ. 0.071 A) and an I. S. (reI. to Fe) = -0.421 mm/sec. For anneals below 770 K the cobalt atoms migrate to site B, which is characterized by a …
13th Annual Rocky Mountain Spectroscopy Conference
13th Annual Rocky Mountain Spectroscopy Conference
Rocky Mountain Conference on Magnetic Resonance
Program and abstracts from the 13th annual meeting of the Rocky Mountain Spectroscopy Conference, hosted by the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, August 9-10, 1971.
A Study Of A Divalent Cation-Selective Electrode, William Stanhope Ryan Jr.
A Study Of A Divalent Cation-Selective Electrode, William Stanhope Ryan Jr.
Master's Theses
The ion-selective membrane electrode, recently introduced commercially, has shown excellent promise as a tool for determining ionic activities and concentrations in solution. It was the intent of the author to study the Orion divalent cation-selective electrode with two objectives.
The first objective of this research was to characterize the response of the divalent cation-selective electrode to calcium and magnesium ions in aqueous solutions. The effect of anions, monovalent cations; and pH upon this response was investigated. An examination was made of the response of this electrode to other divalent cations and of the effect of organic solvents on the membrane …
An Investigation Of Some Free Radicals.|Ni.|Pdecomposition Of Nitrosyl Disulfonate Ion In Polar Non-Aqueous Solvents.|Nii.|Preaction Between 2,2-Diphenyl -1- Picryl Hydrazyl And Nitrosyl Disulfonate Ion Free Radicals, Janan Mary Hayes
Theses and Dissertations
Part I reports the stud y of the decomposition of nitrosyl disulfonate ion in DMSO, acetonitrile, and dichloromethane. A multi-step mechanism involving sulfite ion, sulfite ion radical, and nitrosyl monosulfonate radical as intermediates is proposed. The products of the decomposition are nitrosonium ion, hydroxylamine disulfonate ion, and hydroxylamine trisulfonate ion. A competitive chain reaction was observed when the decomposition occurred in DMSO. The chain reaction was insignificant in carefully dried acetonitrile and dichloromethane. Part II reports the study of the reaction between 2,2-diphenyl-1-picryl hydrazyl (DPPH) and nitrosyl disulfonate ion. Product analysis and kinetic data obtained from stopped-flow procedures suggest that …
Stereochemistry And Circular Dichroism Of Trans-Diacidobisdiamine Complexes Of Cobalt(Iii), Jack A. Tiethof
Stereochemistry And Circular Dichroism Of Trans-Diacidobisdiamine Complexes Of Cobalt(Iii), Jack A. Tiethof
Dissertations
No abstract provided.
The Response Of The Micro-Adsorption Detector To Inorganic Cations, David P. Mckay
The Response Of The Micro-Adsorption Detector To Inorganic Cations, David P. Mckay
Masters Theses
No abstract provided.
Synthesis And Characterization Of Some Dioxane Complexes, James Donald Satterlee
Synthesis And Characterization Of Some Dioxane Complexes, James Donald Satterlee
All Master's Theses
The boron trifluoride, tin (IV) fluoride and titanium (IV) fluoride complexes with 1,4-dioxane have been prepared and studied using infrared techniques. The compositions of the complexes have been determined and correspond to the 1:1 adducts in the case of the tin and titanium compounds. The boron trifluoride adduct is a 2:1 (acid:base) adduct. Infrared spectra in the region 1300 cm.-1 to 550 cm.-1 are given and the effects of coordination upon the ligand vibrations are described.
A Kinetic Analysis Of The Iodination Of Pyruvic Acid And Pyruvate Esters, Mohamed M. Fahmi Hegazi
A Kinetic Analysis Of The Iodination Of Pyruvic Acid And Pyruvate Esters, Mohamed M. Fahmi Hegazi
All Master's Theses
In the present work the relative rates of iodination of pyruvic acid and ethyl and methyl pyruvate have been compared at 25.0° C. These studies allow the determination of the respective free energies of activation for these processes. Measurements have also been carried out at various temperatures to determine the enthalpies and entropies of activation for the spontaneous and base catalysed iodinations of these pyruvate systems. The present thesis also includes a comparison of the solvent deuterium isotope effects associated with the spontaneous rate of iodination of pyruvic acid and the alkyl pyruvates. Also, the catalytic rate coefficients associated with …
The Thermal Decomposition Of 2,2'-Azoisobutane, Mervin Dewain Atwood
The Thermal Decomposition Of 2,2'-Azoisobutane, Mervin Dewain Atwood
Theses and Dissertations
Nitrogen, isobutane, isobutylene and 2,2,3,3-tetramethylbutane are the only products found in the thermal decomposition of 2,2'-azoisobutane. They are the results of the direct free radical dimerization and disproportionation. Ratio of the rate constants of disproportionation to dimerization was found to be 1.9 at 268°C and 4.5% azobutane in helium. This compared with Blackham and Eatough's value of 1.4 at 243°C and 3.6 at 290°C with 4% azobutane in helium. The ratio of the disproportionation to dimerization increased with an increase in temperature. A change in contact time affected the ratio at lower reaction temperatures but had little effect on it …
Studies Of Pig Brain Thiamin Pyrophosphokinase, James Weldon Peterson
Studies Of Pig Brain Thiamin Pyrophosphokinase, James Weldon Peterson
Theses and Dissertations
Pig brain thiamin pyrophosphokinase (TPK) (ATP: thiamin pyrophosphotransferase, EC 2.7.6.2) was purified 260-fold over extracts of brain acetone powder. The purification was followed using a direct, radiometric assay. As determined in an analytical ultracentrifuge and by disc-gel electrophoresis, the most highly purified enzyme preparations were not homogeneous. The purified enzyme has a broad pH optimum extending from 8.3 to 9.3 in phosphate-glycylglycine buffer. It has an isoelectric point at about pH 4.2. For optimal enzymatic activity, the ratio of magnesium to ATP must be 0.6. Any deviation from this ratio causes a rapid drop in enzymatic activity. A study of …
Analytical Aspects Of Laser-Induced Degradation Of Organic And Inorganic Compounds, William T. Ristau
Analytical Aspects Of Laser-Induced Degradation Of Organic And Inorganic Compounds, William T. Ristau
Chemistry and Chemical Biology ETDs
The rapid deposition of energy by means of a pulsed ruby laser to degrade organic and inorganic materials is investigated as an analytical tool. Advantages and disadvantages of using a laser are discussed and compared to current conventional pyrolysis methods. The interaction of laser radiation with matter is briefly discussed.
A number of different organic compounds including saturated and aromatic hydrocarbons, heterocyclic compounds, and polymers have been studied. The degradation products were separated and identified by use of a gas chromatograph. Degradation studies have also been done on a series of inorganic salts including nitrates, sulfates, thiosulfates, and oxalates. The …
The Synthesis Of Some New Condensed Pyridazines, Pyridazine N-Oxides And Pyrimidines As Potential Chemotherapeutic Agents, Donald E. Pichler
The Synthesis Of Some New Condensed Pyridazines, Pyridazine N-Oxides And Pyrimidines As Potential Chemotherapeutic Agents, Donald E. Pichler
Chemistry and Chemical Biology ETDs
No abstract provided.
A Study Of The Acetic Anhydride Method For The Determination Of Citric Acid, Russell Kent Odland
A Study Of The Acetic Anhydride Method For The Determination Of Citric Acid, Russell Kent Odland
Master's Theses
Citric acid is an important compound of many systems. Numerous methods, both qualitative and quantitative, have been used for the determination of the compound. Some of the biological systems investigated include fermentation studies, action on yeasts, antioxidant in fruits, additive in bakery goods and salad dressing preparations, amounts in vegetables, and others.The above examples are not complete; they only show the varied applications of citric acid. The purpose of this project was to investigate a quantitative spectrophotometric method using anhydrous conditions based on the citric acid-acetic anhydride-pyridine reaction. Conditions affecting the reaction were investigated and optimized for maximum sensitivity and …
Electron Densities For Homonuclear Diatomic Molecules From The Thomas-Fermi-Dirac Theory, Jerry Goodisman
Electron Densities For Homonuclear Diatomic Molecules From The Thomas-Fermi-Dirac Theory, Jerry Goodisman
Chemistry - All Scholarship
Electron densities are calculated from approximate solutions to the Thomas-Fermi-Dirac equation for homonuclear diatomic molecules. The accuracy of expectation values calculated from these densities is assessed. In general, one obtains fair agreement with self-consistent-field and experimental results, but this is insufficient when a property is a difference between electronic and nuclear contributions. An important example is the Hellmann-Feynman force on a nucleus, the net force necessarily being repulsive, as for closed-shell atoms. Forc and energy results for such a situation are compared with experiment. Finally, it is shown that a modified theory, previously applied to atoms, gives improvement in expectation …
Approaches To The Synthesis Of Bis-Acenaphth [1,2-A] Acenaphthene, Kenneth Neal Boudette
Approaches To The Synthesis Of Bis-Acenaphth [1,2-A] Acenaphthene, Kenneth Neal Boudette
Honors Theses
The purpose of this project was the synthesis of bis-acenaphth[l,2-a] acenaphthene. The synthetic route attempted was the preparation of 1,8-naphthalylnaphthalene by reacting 1,8-dilithionaphthalene with acenaphthene- quinone followed by oxidation with lead tetracetate and treatment of the diketone with 1,8-dilithionaphthalene to give the product.
Study Of The Radiolysis Of Aqueous Dichloromethane, Joseph Herbert Dal Pian
Study Of The Radiolysis Of Aqueous Dichloromethane, Joseph Herbert Dal Pian
Honors Theses
Aqueous solutions of dichloromethane have been irradiated with a cobalt-60 gamma source. Products of the radiolysis have been determined in order to formulate the mechanism of the radiation induced decomposition. Chemical analysis of irradiated solutions has shown that hydrochloric acid and formic acid are among the products of the decomposition. The effect of oxygen and dichloromethane concentrations on the production and yield of chloride ion has been determined. From the results, a mechanism for the radiolysis of aqueous dichloromethane in the presence of oxygen has been deduced.
Preparation Of Some Alkynes And Alkenynes, Edward John Lamby
Preparation Of Some Alkynes And Alkenynes, Edward John Lamby
Honors Theses
The following thesis concerns the preparation of several alkynes and their conversion to alkenynes. Alkynes are of interest because of their potential biological activity (1), general reactivity to boranes (2), complexing ability with some transition metals (3), as well as other general reactions of π bonds (4). It was the intention of this investigation to prepare several alkynes with varying degrees of steric hindrance and evaluate the effect of this property. Double bonds were incorporated in several of these compounds to aid in the assessment.
The Radiolysis Of Aqueous Solutions Of Dichloromethane, Steven Michael Odre
The Radiolysis Of Aqueous Solutions Of Dichloromethane, Steven Michael Odre
Honors Theses
Aqueous solutions of dichloromethane have been irradiated with a cobalt-60 gaama source. Products of the radiolysis have been determined in order to formulate the emchanism of the radiation induced decomposition. Chemical studies have shown that hydrocholoric acid and hydrogen peroxide are two of the major products of the radiolysis. Traces of formaldehyde have also been found. The effect of oxygen and dichloromethane concentrations on product yields was determined. It has been found that the product yields are independent of dose rate. The Proposed mechanism is initiatied by the hydrated electron and the hydroxyl radical - both products of the radiolysis …
Photochemical Reactions Of Some Benzyl Compounds, Thomas Wesley Lesniak
Photochemical Reactions Of Some Benzyl Compounds, Thomas Wesley Lesniak
Honors Theses
Zimmerman and Sandel have investigated many photolytic reactions involving benzyl compounds and have hypothesized the intermediate to be a carbonium ion. The addition of a meta-electron donating group has been used to increase the stability of the carbonium ion intermediate. 3, 5- Disubstituted benzyl carbonium ions have added stability.
The Photolysis Of Phenylglycine And The Synthesis Of Α-Deuterated M-Anisaldehyde, Alan Nathan Meisel
The Photolysis Of Phenylglycine And The Synthesis Of Α-Deuterated M-Anisaldehyde, Alan Nathan Meisel
Honors Theses
Attempts were made to produce mandelic acid by irradiating phenylglycine in both acidic and basic aqueous solutions but no mandelic acid was detected.
The Fluorescence And Phosphorescence Of Glycine -- A First Step In The Determination Of Glycine Carbamate, Henry George Fein
The Fluorescence And Phosphorescence Of Glycine -- A First Step In The Determination Of Glycine Carbamate, Henry George Fein
Honors Theses
Cassidy (1) fully outlines the historical progress of research to 1968 about the carbamate reaction; this paper will simply summarize that effort. It is presently believed that carbon dioxide is transported by the blood in three ways: 1) dissolved CO2 and carbonic acid, 2) bicarbonate ions, and 3) carbamate. Roughton and Rossi-Bernardi (10) have proposed the use of a glycylglycine and CO2 model for the carbamate reaction. Instead of the barium precipitate method, they have used a pH and pCO2 electrode system to measure the uptake of CO2. Since the dissolved CO2 and HCO3 can be calculated from the pCO2 …
Glycine Carbamate Derivatives, David Clark Cable
Glycine Carbamate Derivatives, David Clark Cable
Honors Theses
The formation of a carbamate on hemoglobin is one method proposed for carbon dioxide transport in the blood. As of yet, no direct method has been reported for quantitatively determining to what extent carbamate formation occurs. The phosphorescence of glycine carbamate is of interest in this problem. Glycine is structurally similar to the globin endings, so that it presents a model that is simpler and more easily studied but still contains a sufficient degree of similarity to hemoglobin for the purpose of studying this reaction. Phosphorescence spectroscopy has been proposed a possible method for direct quantitative analysis of glycine carbamate. …
Critical Examination Of The Uniform Charge Cloud Method, Frederick R. Maxfield
Critical Examination Of The Uniform Charge Cloud Method, Frederick R. Maxfield
Honors Theses
The Uniform Charge Cloud Method, a model used to describe atoms and molecules, has been investigated. In the model, electrons are viewed as spheres with a constant charge density throughout their volume. In previous studies, it was found that the interelectron repulsion energies calculated for helium were too high, bond distances calculated for molecules were too short, and the model was unable to predict term values in accordance with Hund's Rules. In order to reduce these errors, electron correlation was introduced into the model. It was found that the errors were too large to be corrected by electron correlation. The …
Mercury Content Of Tobacco Products, Karen S. Mrozek
Mercury Content Of Tobacco Products, Karen S. Mrozek
Senior Scholar Papers
Mercury contamination of food products results from contact with soil, water, and air polluted with mercury from industrial sources, as well as from the use of mercury-containing pesticides and fungicides on plants. A method was developed for extracting mercury from tobacco products. The mercury content of various tobacco products was determined, using an atomic absorption spectrophotometer.
I. Studies Toward The Synthesis Of Echinodithianic Acid And Ii. The Temperature Dependent Nmr Spectrum Of Methyl N-Acetylsarcosinate, Alan Leroy Love
I. Studies Toward The Synthesis Of Echinodithianic Acid And Ii. The Temperature Dependent Nmr Spectrum Of Methyl N-Acetylsarcosinate, Alan Leroy Love
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Approaches to the preparation of echinodithianic acid (5) from 2,5-dicarbomethoxy-1,4-dithiane (1) were not successful, due to the inability to carboxylate or carboalkoxylate 1 at carbons 2 and 5. Studies toward the synthesis of 5 utilizing methyl 2-acetamidoacrylate (8) have been investigated. The electrophilic addition of sulfur dichloride to 8 yielded bis-(2-acetamido-2-carbo-methoxyvin-1-yl) sulfide, while the addition of thiocyanogen chloride to 8 produced methyl 2-acetamido-3-thiocyanato-acrylate.
As electrophilic additions of unsymmetrical dipolar reagents to methyl 2-acetamidoacrylate (8) are not reported in the literature, the addition of hydrogen bromide to 8 was studied to determine the orientation effect of the acetamido group.
Methyl 2-acetamido-2-bromopropionate …