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Articles 32911 - 32940 of 34529
Full-Text Articles in Physical Sciences and Mathematics
Synthesis Of Derivatives Of Pyrido [3,4-D]Pyridazines, Diane (D'Ottavio) Martin
Synthesis Of Derivatives Of Pyrido [3,4-D]Pyridazines, Diane (D'Ottavio) Martin
Chemistry and Chemical Biology ETDs
The current interest in the biological activity of certain 1 ,4-disubstituted pyrido[2 ,3-d]pyridazines prompted the investigation of various derivatives of the isomeric pyrido[3,4-d]pyridazine ring system. Thus, 1,4 dichloro[3,4-d]pyridazine was treated with thiourea and the intermediate thiouronium salt hydrolyzed to give pyrido[3, 4-d]pyridazine-1,4(2H,3H)-dithione which was subsequently alkylated to give 1,4-bis(alkylthio)pyrido[3,4-d]pyridazines. On the other hand, 1,4-bis(arylthio)pyrido[3,4-d]pyridazines were prepared by the reaction of 1,4-dichloropyrido[3,4-d]pyridazine with various substituted thiophenols. Furthermore, treatment of 1,4-dichloropyrido[3,4-d]pyridazine with a variety of substituted anilines gave the corresponding 1,4-disubstituted aniline derivatives, whereas reaction with alkylamines afforded only the 1(4)-chloro-4(1)-alkylaminopyrido[3,4-d]pyridazines. When 1-chloropyrido[3,4-d]pyridazine-4(3H)-one or 4-chloropyrido[3,4-d]pyridazine-1(2H)-one was treated with hydrazine, the corresponding …
Cationic Copolymerization Of B-Pinene And Styrene, Charles Peter Snyder
Cationic Copolymerization Of B-Pinene And Styrene, Charles Peter Snyder
Honors Theses
Cationic polymerizations are the least understood of all polymerization reactions. Perhaps even less understood are copolymerizations using cationic catalysts. Very little can be found in the literature concerning B-pinene and styrene copolymers. This work was done to shed some light on this interesting subject.
Attempted Synthesis Of Diethyl 7-Dimethylsilabicyclo 2.2.1 Hepta-2,5-Dione-1,4-Dioate, David Kenneth Tart
Attempted Synthesis Of Diethyl 7-Dimethylsilabicyclo 2.2.1 Hepta-2,5-Dione-1,4-Dioate, David Kenneth Tart
Honors Theses
An attempt was made to synthesize diethyl 7-dimethylsilabicyclo [2.2.1) hepta-2,5-dione-l,4-dioate by reacting dimethyldichlorosilane with the dianion of 1,4-dicarbethoxy- 2,5-cyclohexadione. The products formed in the reaction were silicones and 0-silylated polymeric materials. If any of the desired product was formed, it was not detected.
Synthesis Of C14-Labeled Bis (P-Chlorophenyl) Acetic Acid (Dda), William Michael Silver
Synthesis Of C14-Labeled Bis (P-Chlorophenyl) Acetic Acid (Dda), William Michael Silver
Honors Theses
The past three decade has seen the widespread use of DDT as an insecticide. As a persistent insecticide, its use has prompted a great amount of research into the fate of DDT in living organisms. A large number of metabolites of DDT has been found and many identified, although not all of the metabolites were found in all of the experimental bacterium, insects, or mammals.
Photochemical Solvolysis Of Optically Active 3,5-Dimethoxy-Α-D-Benzyl Acetate, Peter Jerry Frank
Photochemical Solvolysis Of Optically Active 3,5-Dimethoxy-Α-D-Benzyl Acetate, Peter Jerry Frank
Honors Theses
The purpose of this work was the stereochemical study of the photochemical solvolytic reaction of 3,5-dimethoxybenzoic acid, optically active 3,5-dimethoxy-α-d-benzyl alcohol was prepared. The specific rotation of the alcohol was compared to the alcohol produced from the photochemical solvolytic reaction of 3,5-dimethoxy-α-d-benzyl acetate.
The Preparation And Kinetics Of Sterically Hindered Gold (Iii) Complexes, David Luther Fant
The Preparation And Kinetics Of Sterically Hindered Gold (Iii) Complexes, David Luther Fant
Honors Theses
The purpose of this research was to prepare and study complexes with steric hindrance greater than that of the dien complex but less than that of the Et4dien complex.
Synthetic Approaches To Certain Acenapthalene Drivatives, Douglas Jeffrey Binder
Synthetic Approaches To Certain Acenapthalene Drivatives, Douglas Jeffrey Binder
Honors Theses
The purpose of this investigation is the synthesis of bis- acenaphth- (1, 2a)- acenaphthene. The experimental procedures used generally follow those of previous workers. The use of 1, 8- dibromonaphthalene is necessary throughout the synthesis. The preparation used follows that of letsinger, after a preferred synthesis of 8- bromo- 1- naphthotic acid. The latter compound reacted via a modified Hunsdiecker reaction to yield 1, 8- dibromo- naphthalene. Other approaches tried never seemed to result in improved yields, or were successful. Besides this approach to 1, 8- dibromonaphthalene, an attempt to circumvent its need has been made by running a dilute …
1-3 Dipolar Cycloadditions Of Nitrile Ylides, Steven Paul Braff
1-3 Dipolar Cycloadditions Of Nitrile Ylides, Steven Paul Braff
Honors Theses
1-3 dipolar cycloaddition is the union of a 1-3 dipole, a-b-c, with a system containing a multiple bond, d-e, to form a five membered ring. In this scheme, center c contains an electron sextet, and concommitant positive charge, while center c contains an unshared pair of electrons and is the anionic center of the dipole. In the cycloaddition reaction, the 1-3 dipole and the multiple bond system (called the dipolarophile), collapse to form a five membered ring with loss of all formal charges. All together, eighteen 1-3 dipolar systems have been mentioned. The synthetic potential with respect to heterocyclic adducts …
The Developement [Sic] Of Phosphorometric, Fluorometric And Absorption Analyses For The Measurement Of Carbamates And Carbamic Acids As An Explanation Of Carbon Dioxide Transport In Blood, Edward Theodore Gray
The Developement [Sic] Of Phosphorometric, Fluorometric And Absorption Analyses For The Measurement Of Carbamates And Carbamic Acids As An Explanation Of Carbon Dioxide Transport In Blood, Edward Theodore Gray
Honors Theses
Phosphorometric, flourometric, and absorption analyses have been developed for the measurement of amino acids, carbamic acids, and carbamates. The absorption analysis may be done in any solvent while the other two methods are limited to non-re-emitting solvents. Water is not excluded in any of the analyses. A carbamate or carbamic acid can be detected even in the presence of amino acids as low as 0.5%, with an overall accuracy of ± 0.3)%. Tentative assignments have been made for the n, π* direct triplet excitation bands for the carbonyls of glycine and its carbamic acid, acetyl chloride, ethyl acetate, and acetamide. …
Some Aspects Of Quantum Mechanics In Chemical Theory, Thomas Freeman Babson
Some Aspects Of Quantum Mechanics In Chemical Theory, Thomas Freeman Babson
Honors Theses
The physics of microscopic phenomena is called quantum mechanics. When quantum mechanics is extended to the macroscopic scale, the classical macroscopic physics results. Atomic interactions such as the formation of bonds between atoms falls into the range of physics described by quantum mechanics. Because of the interest of a chemist in such interatomic effects, it seems reasonable that a chemist would be interested in quantum mechanics because it is the physics governing these effects. The point of this thesis is to present some of those aspects of quantum mechanics that are directly applicable to molecular systems and that can aid …
An Acid Alkylation Of 8-Hydroxyquinoline, James D. Searcy
An Acid Alkylation Of 8-Hydroxyquinoline, James D. Searcy
Morehead State Theses and Dissertations
A thesis presented to the faculty of the School of Science and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by James D. Searcy on May 11, 1972.
Chelation Of Two Polyhydroxyamines With Copper (Ii) Ion, David H. Powell
Chelation Of Two Polyhydroxyamines With Copper (Ii) Ion, David H. Powell
Master's Theses
Two polyamines, 2,8-bishydroxymethyl-2,8-dimethyl- 3, 7-diaza-1,5,9-nonanetriol and 2,8-bishydroxymethyl-2,8- dimethyl-3,7-diaza-l,9-nonanediol, were prepared and the coordination of these compounds with Cu (II) ions in solution was investigated. Spectrophotometric study of the solutions of these compounds gives evidence of the formation of two complexes, containing one mole of ligand per metal ion and two moles of ligand per metal ion, respectively. The two stability constants for these complexes and the basicity constants for these ligands were calculated from potentiometric titrations at 30°C. A compadson of the stabj lity constants and basici ty cons tan ts for the two compounds was made to determine the …
Synthesis And Metal Coordination Properties Of Some Cyclic Polyethers And Polythioethers, Barry Lant Haymore
Synthesis And Metal Coordination Properties Of Some Cyclic Polyethers And Polythioethers, Barry Lant Haymore
Theses and Dissertations
Thermodynamic values for cation-cyclic polyether interactions for several systems are reported and discussed in light of ligand geometry, cation selectivity, solvent effects, structure, stoichiometry and the nature of the coordinate bond. Cyclic polyethers are shown to be remarkably good ligands even in water and to have marked selectivity for d0, d10 and d10 s2 cations. Syntheses of one new cyclic polyether and several new mixed cyclic polyether-thioethers are reported. Cyclic chelates with smaller rings are shown to prefer smaller cations, but this selectivity is masked by the hydration energy of the cation. Except for thiophillic cations such as Hg2+ and …
Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Mark J. Rowe
Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Mark J. Rowe
Theses and Dissertations
The synthetic reaction of ribonuclease T_1 has been studied as to its potential for the synthesis of oligoribonucleotides of defined base sequence. Conditions have been determined for maximum synthesis with respect to percentage incorporation of both guanosine 2',3'-cyclic phosphate (donor), and cytidine (acceptor). With regard to maximum acceptor incorporation, a donor blocked at the 5'-hydroxyl has been used to drive the reaction. It has also been shown that acceptor incorporation decreases as the chain-length increases up to the hexanucleotide. Synthesis of a 3'-blocked substrate for polynucleotide phosphorylase for use in chain termination studies was attempted using adenylate kinase. In this …
The Synthetic Chemistry Of Carboxyalkyl-P, P-Diphenyl Phosphines, Larry S. Andrews
The Synthetic Chemistry Of Carboxyalkyl-P, P-Diphenyl Phosphines, Larry S. Andrews
Chemistry Honors Papers
This 55 page thesis examines the preparation of carboxyalkyl-P and P-diphenyl phosphines to determine their acidity characteristics as a function of structure and to characterize their ability to function as chelating agents.
A New Method For The Preparation Of Alkylnaphthyl Ethers And Sulfides, Edward Ying-Shih Chen
A New Method For The Preparation Of Alkylnaphthyl Ethers And Sulfides, Edward Ying-Shih Chen
Theses and Dissertations
The reaction of monohalonaphthalenes with metal alkoxides and mercaptides in a solvent mixture of the corresponding alcohol and dimethyl sulfoxide (DMSO) has been studied. These reactions are convenient methods for the preparation of alkylnaphthyl ethers and sulfides. Only direct nucleophilic substitution was observed in the reactions of bromonaphthalenes with sodium methoxide and sodium nbutyl mercaptide. The reaction of fluoronaphthalene with potassium t-butoxide also proceeded by way of direct nucleophilic substitution rather than the 1,2-dehydronaphthalene intermediate as in the reactions of bromonaphthalene with potassium t-butoxide. The use of a base which is weaker than t-butoxide can change the apparent reaction mechanism …
Electrolytic Synthesis Of [Gamma]-Diketones, Leon F. Pahler
Electrolytic Synthesis Of [Gamma]-Diketones, Leon F. Pahler
Theses and Dissertations
Four γ-diketones were synthesized by using a modification of the Kolbe electrolytic condensation of β-ketocarboxylic acids. [--see equation in thesis--] The following γ-diketones were synthesized in moderate yields: 2,5-hexanedione, 4,7-decanedione, 2,2,7,7-tetramethyl- 3,6-octanedione, and 1,4-diphenyl-1,4-butanedione (34, 39, 23, and 27, respectively). However, attempted preparation of the following γ-diketones failed: 3,4-dimethyl- 2,5-hexanedione, 3,3,4,4-tetramethyl-2,5-hexanedione, and 1,4-di(2-thienyl)-1,4-butanedione. Attempts to electrolytically condense α-alkyl and α, α-dialkyl substituted monocarboxylic acids have been reported and all attempts have ended in failure; similarly, the attempts to synthesize 3,4-dimethyl and 3,3,4,4-tetramethyl- 2,5-hexanedione from 2-methyl and 2,2-dimethyl-3- oxobutanoic acid, respectively, failed. The preparation of 1,4-di(2-thienyl)-l,4-butanedione failed because the product or …
Rhenium Catalyzed Hydrogenation Of Maleic Anhydride And Crotonaldehyde, William Russel Dixon
Rhenium Catalyzed Hydrogenation Of Maleic Anhydride And Crotonaldehyde, William Russel Dixon
Theses and Dissertations
The preparation of a number of supported rhenium catalysts is reported. The determination of their activity and selectivity and of optimal reaction parameters for the reduction of maleic anhydride and crotonaldehyde is reported. Optimal time of hydrogenation was chosen as one hour and pressures were chosen as 2000 psig for crotonaldehyde and 3000 psig for maleic anhydride. Quantitative reduction of maleic anhydride to tetrahydrofuran occurred at 275° with charcoal supported rhenium catalysts. Lower temperatures (ca. 200°) produce quantitative amounts of butyrolactone. Unsupported catalysts at low temperatures (100°) selectively reduce crotonaldehyde to crotyl alcohol, but at very low conversion rates. Temperatures …
Toward Hydrogen Bonds Of Predictable Geometry, Robert Shao-Chih Hsu
Toward Hydrogen Bonds Of Predictable Geometry, Robert Shao-Chih Hsu
Theses and Dissertations
A literature review on the geometry of hydrogen bonding showed that the geometry is often de-emphasized or even ignored, probably because of the inherent flexibility of many systems studied. Examination of molecular models suggested the geometrically constrained bicyclo [2, 2, 1] heptane system wherein hydrogen bond distances and angles might be more easily predicted. Dihydroboration-oxidation of norbornadiene was shown to yield exo, exo-2,5-norbornadiol, thus clarifying uncertainties in the literature. 2, 5-Norbornadiol was oxidized to the corresponding dione, heretofore inadequately characterized. Several derivatives of the dione were prepared, and spectral data were accumulated for the dione, its precursor, and its derivatives. …
Acid-Base Titrations In Sulfolane., Francine O. Lawrence
Acid-Base Titrations In Sulfolane., Francine O. Lawrence
Chemistry and Chemical Biology ETDs
A study of the solvent effects of sulfolane (tetrahydrothiophene 1,1-dioxide, tetramethylene sulfone) upon a series of acids and several bases has been conducted. A procedure is presented for purifying sulfolane which results in a solvent of very low water content (5 x 10^-4 M ) and very few impurities, as shown by its cooling curve. Potentiometric and conductometric measurements of additions of acids and bases to purified sulfolane and of various acid-base titrations were made. The series of carboxylic acids included benzoic, orthomethoxybenzoic, and three different monochlorobenzoic acids. The bases investigated included sodium methoxide, pyridine, and diphenylguanidine. Interpretation of the …
19f Nmr And Bx3 Complexes, Nancy Toole Tucker
19f Nmr And Bx3 Complexes, Nancy Toole Tucker
Morehead State Theses and Dissertations
A thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Chemistry by Nancy Toole Tucker on April 21, 1972.
Preparation And Reactions Of 2-Benzo [B] Thienylsodium, Larry Kennard
Preparation And Reactions Of 2-Benzo [B] Thienylsodium, Larry Kennard
Morehead State Theses and Dissertations
A thesis presented to the faculty of the School of Science and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Chemistry by Larry Kennard on April 21, 1972.
Influence Of An External Electric Field On The Charge Transfer State Of The Tcne-Trans-Stilbene Molecular Complex, Craig J. Eckhardt
Influence Of An External Electric Field On The Charge Transfer State Of The Tcne-Trans-Stilbene Molecular Complex, Craig J. Eckhardt
Craig J. Eckhardt Publications
An experimental investigation of the effect of an external electric field on the absorption spectrum of the tetracyanoethylene-trans-stilbene molecular complex in cyclohexane solution yielded values of 1.1±0.1 D for the ground state electric dipole moment and 10.5±0.9 D for the change of the electric dipole moment upon transition to the charge transfer excited state. The ground state electric dipole moment determined by the electro-optic effect is in agreement with the value of 1.4±0.5 D obtained from the dielectric constant measurements made on solutions of the complex. The directions of the transition moment, the ground state electric dipole moment, and the …
A Spectrophotometric Study Of The Reaction Between Benzoyl Peroxide And N, N-Dimethyl-P-Phenylenediamine, Bertha Cosby King
A Spectrophotometric Study Of The Reaction Between Benzoyl Peroxide And N, N-Dimethyl-P-Phenylenediamine, Bertha Cosby King
Master's Theses
A special need for methods to determine low concentrations of organic peroxides originated because of their hazardous and harmful effects, Even the small amounts of organic peroxide formed by autoxidation in ethers exposed to air make the ethers highly explosive and unsuitable for use as anesthesia or laboratory solvents. The formation of organic peroxides in fats and oils causes rancidity. They have been named as pollutants, and some of them are known to have detrimental physiological effects.
The purpose of this research was to improve this method of analysis and to determine better conditions for the measurement of color by …
Kinetics Of Free Radical-Initiated Polymerization Of Α-Methylstyrene In The Region Of The Ceiling Temperature, Fred E. Huang
Kinetics Of Free Radical-Initiated Polymerization Of Α-Methylstyrene In The Region Of The Ceiling Temperature, Fred E. Huang
Masters Theses
No abstract provided.
The Relationship Between Degree Of Clay Dispersion And The Optical And Pore Properties Of Starch - Clay Coatings, Chinu S. Dalal
The Relationship Between Degree Of Clay Dispersion And The Optical And Pore Properties Of Starch - Clay Coatings, Chinu S. Dalal
Masters Theses
No abstract provided.
Development Of An Ultra High Shear Recording Viscometer, David C. Thornton
Development Of An Ultra High Shear Recording Viscometer, David C. Thornton
Masters Theses
No abstract provided.
Heats Of Combustion Of Alpha-Methylstyrene Oligomers, Dale Keith Humbert
Heats Of Combustion Of Alpha-Methylstyrene Oligomers, Dale Keith Humbert
Masters Theses
Introduction
The heat of polymerization (∆Hp) of α-methylstyrene (AMS) has been a source of study for many years. The structure of AMS is shown in Figure 1.
The first quantitative work was done by Roberts and Jessup.1 Their values were more positive than those theoretically calculated by Flory2 and compared with ∆Hp data of other systems. This was not totally unexpected and could be satisfactorily explained on the basis of steric hindrance and loss of resonance energy of conjugation. This steric hindrance arose from "head-to-tail" polymerization of the 1, 1-disubstituted ethylene structure.3 Their data …
Continuous Wave Co2 Laser Degradation And Mass Spectrometric Analysis Of Organic Polymers., Stanley G. Coloff
Continuous Wave Co2 Laser Degradation And Mass Spectrometric Analysis Of Organic Polymers., Stanley G. Coloff
Chemistry and Chemical Biology ETDs
Previous laser-mass spectrometer and laser-gas-chromatographic instruments for study of organic polymer degradation have used high power pulsed lasers (ruby, Nd-glass) which limit sample characterization due to extensive fragmentation.
A new experimental technique has been developed for high temperature pyrolysis and rapid analysis of organic polymers. The experimental technique combines a low power continuous wave CO2 laser for sample pyrolysis and a time-of-flight mass spectrometer to analyze degradation products. The laser built for use in this study was a continuous flow CO2 gas-molecular laser excited by high voltage direct current with maximum power of 10 watts at a wavelength of 10600 …
Spectral Studies Of Hydrogen Bonding In Alcohols, Linda Moree Higgins Collins
Spectral Studies Of Hydrogen Bonding In Alcohols, Linda Moree Higgins Collins
Masters Theses
The phenomenon of hydrogen bonding in alcohols has been known since the early 1900's. Using three series of alcohols, benzyl alcohols, norbornanols and substituted naphthalene alcohols, it was hoped that some meaningful data could be presented to help clarify and expand some of the theories on alcohol association. The techniques to be utilized were ir and nmr spectroscopies.
The synthetic route for those compounds that were not available as alcohols involved reduction of the corresponding acids to alcohols by use of lithium aluminum hydride. The strengths of the various types of hydrogen bonds, intramolecular and intermolecular, were detected by nmr …