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Mechanisms Of Reactions Of Alkenesulfonyl And 2-Substituted Ethanesulfonyl Chlorides, John Henry Hillhouse
Mechanisms Of Reactions Of Alkenesulfonyl And 2-Substituted Ethanesulfonyl Chlorides, John Henry Hillhouse
Digitized Theses
This thesis describes the mechanisms of the reactions of some simple alkenesulfonyl chlorides and 2-substituted ethanesulfonyl chlorides with tertiary amine bases in aqueous and organic media.;Chapter 1 describes the reactions of ethenesulfonyl chloride and trans-1-propene-1-sulfonyl chloride with water in the presence and absence of substituted pyridines. The former reactions are concluded to proceed by S(,N)2' attack of the pyridine based on the sulfonyl chloride to generate ultimately a pyridine betaine and the pyridinium alkenesulfonate. The formation of the alkenesulfonate anion from the alkenesulfonyl chloride by reaction of the pyridine base corresponds to the first well-established example of a vinylogous nucleophilic …
Adsorption Of Cations At The Sulphide/Water Interface, Gilles Elziar Jean
Adsorption Of Cations At The Sulphide/Water Interface, Gilles Elziar Jean
Digitized Theses
The adsorption of aqueous metal ions on various sulphide minerals was studied as a function of time, pH, surface composition and chemical speciation.;In the first part of this work (Chap. 3) the reaction between various types of gold solutions and several minerals was followed using XPS and SEM. Gold from chloro auric solutions was reduced quickly from Au(III) to Au(O) by every sulphide mineral studied. SEM showed the gold to be unevenly distributed on the surface in the form of agglomerates. Oxide minerals did not reduce gold to any great extent. The gold was shown to adsorb on the sulphide …
Histamine Metabolism During Asthma Induced By Inhalation Challenge, Henry Cheuk-Ki Poon
Histamine Metabolism During Asthma Induced By Inhalation Challenge, Henry Cheuk-Ki Poon
Digitized Theses
In order to ascertain a role of histamine (HM) in the mediation of induced asthma, HM and Diamine Oxidase activity (DAO) were determined serially in plasma together with the Forced Expiratory Volume in the first second (FEV(,1)) in 18 subjects inhaling methacholine(MCH) by increments to permissible limits of 224 cumulative units (cu). HM was measured in plasma ultrafiltrates by an isotropic assay based upon the specificity of HM-N-methyltransferase harvested from rat brains. DAO was determined with o-dianisidine in plasma buffered at pH 7.4. Thirteen asthmatics were bronchial Responders. The provocative dose of MCH yielding a 20% FEV(,1) fall (PD(,20) -FEV(,1)) …
Theoretical And Experimental Studies In Visible Laser Spectroscopy, Akira Brian Yamashita
Theoretical And Experimental Studies In Visible Laser Spectroscopy, Akira Brian Yamashita
Digitized Theses
In this thesis, two different aspects of the interaction of radiation with molecules are studied. First, a previously-derived exact solution to the time-dependent Schroedinger equation describing the interaction between a sinusoidally-oscillating field and an N-level atomic or molecular system is used to examine the temporal and steady-state behaviour of a five-level model molecular system. Secondly, the technique of polarization labelling spectroscopy is used to study the E 0(,g)('+) state of the iodine molecule.;The behaviour of the five-level system, consisting of a ground state and four "nearly degenerate" excited states, is studied for various experimental conditions, and for single- and three-photon …
The Effects Of Bulk Diffusion On The Electrolytic Nucleation And Growth Of Silver On Semiconductors, Daniel Frank Heisler
The Effects Of Bulk Diffusion On The Electrolytic Nucleation And Growth Of Silver On Semiconductors, Daniel Frank Heisler
Digitized Theses
This thesis is concerned with an experimental and a theoretical study of the effects of bulk diffusion on the electrolytic nucleation and growth of silver deposits on tin oxide-coated glass and on glassy carbon. The existing nucleation and growth theory is extended to cover cases where the electrode concentration is a function of time. The manner in which the electrode concentration varies with time depends on the transport of metal ions through the bulk of the solution. The time dependent concentration functions are coupled with solutions of the differential equations that describe transport in solution.;Finite difference calculations are done on …
Spectroscopic And Photovoltaic Properties Of Monolayer Films Of A Porphyrin Dye, Jennifer Ann Bardwell
Spectroscopic And Photovoltaic Properties Of Monolayer Films Of A Porphyrin Dye, Jennifer Ann Bardwell
Digitized Theses
A free-base porphyrin dye, 4-(5-carboxyphenyl)-10,15,20-tritolylporphyrin (TTPa) formed well-behaved monomolecular films at the air-water interface. The carboxylic acid was the hydrophilic portion, and became ionized at subphase pH > 7.3.;The presence of two or more two-dimensional crystalline phases in these films on the aqueous surface under certain conditions was inferred from the observation of visible, inhomogeneous specular reflection from the films.;A spectroscopic study of Langmuir-Blodgett monolayers indicated three different species existed in the films as a function of the pH to which the subphase was buffered. One species was assigned as the monomer; the others as aggregates. One of the aggregates exhibited …
The Photophysics Of Tryptophan, Eva Frances Templeton
The Photophysics Of Tryptophan, Eva Frances Templeton
Digitized Theses
The fluorescence of tryptophyl residues in proteins has been used as a probe of the protein environment for some time. However the reasons for the unique fluorescence properties of tryptophan in solution are still poorly understood.;Part I of this thesis is concerned with studying the photophysics of indole and tryptophan derivatives in solution, as a function of solvent, deuteration and temperature. The time-resolved fluorescence behaviour was studied to examine the reasons for the double exponential decay kinetics of some tryptophan derivatives. The quenching of the fluorescence of tryptophan by hydrogen and deuterium ions was modelled and the results indicated a …
Studies In Surface Photochemistry, Linda Joanne Johnston
Studies In Surface Photochemistry, Linda Joanne Johnston
Digitized Theses
The behaviour of photochemically generated radical pairs on a silica gel surface was compared with results obtained in other restricted environments and in solution. Particular emphasis was placed upon the adsorbed radicals' surface mobility as measured by the amount of nongeminate recombination of the original radical pair.;Benzyl radical pairs were generated by photolysis of 4-methylbenzyl-4-methoxyphenyl acetate, 1-(4-methylphenyl)-3-(4-methoxyphenyl)-2-propanone and 4,4'-methoxy-methyldibenzyl sulfone adsorbed on silica gel. The amounts of geminate recombination determined from the dibenzyl product ratios indicated that substantial movement occurs for absorbed benzyl radicals. The surface mobility was influenced by both the photolysis temperature and the radical pair multiplicity but …
Dynamics Of The Eukaryotic Cell Surface - Lectin Binding To Model Membranes, Nika Victoria Ketis
Dynamics Of The Eukaryotic Cell Surface - Lectin Binding To Model Membranes, Nika Victoria Ketis
Digitized Theses
Transmembrane glycoproteins, glycophorin and the Concanavalin A receptor, were assembled into large multilamellar liposomes. Lectin binding to these simple model membranes was positive-cooperative. The high affinity lectin binding to liposomes was influenced by the presence of unrelated macromolecules (serum albumin and Dextran T-500) at the membrane surface. Since under appropriate conditions the model membrane system appeared to accurately mimic the positive-cooperative behavior observed for binding of various lectins to intact cells, it is suggested that the source of the high affinity binding and its positive-cooperative nature in the described system is the lectin-induced, surface coat dependent 'chelate' or 'avidity' effect. …
Some Problems In Intermolecular Forces And Statistical Mechanics, Kyoko Watanabe
Some Problems In Intermolecular Forces And Statistical Mechanics, Kyoko Watanabe
Digitized Theses
The initial part of this work is concerned with the construction and validity of model potential energies while the second part involves the use of statistical mechanical perturbation theory to evaluate some of the bulk properties of liquids for various types of potential models.;A previously developed potential model for isotropic intermolecular interactions is used for the construction of reliable potentials for interactions of unlike noble gas atoms. The potential model has essentially only one adjustable parameter which controls the balance between its exchange and Coulomb energy components. The parameters in the model potentials are determined by fitting second virial coefficient …