31 |
A spectral and photochemical study of ethyl iodideGinsburg, Eli, January 1900 (has links)
Thesis (Ph. D.)--New York University, 1934. / Vita. Bibliography: p. 50-51.
|
32 |
Development of a Monte Carlo simulation method for use in investigating CT (Computed Tomography) mammographyThacker, Samta C. January 2004 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: CT Mammography; Monte Carlo. Includes bibliographical references (p. 45-48).
|
33 |
The electron spin resonance absorption of two solid states paramagnetic centersDoyle, Larry R. January 1961 (has links)
Thesis (M.S.)--University of California, Berkeley, 1961. / "Chemistry General" -t.p. "TID-4500 (16th Ed.)" -t.p. Includes bibliographical references (p. 53-55).
|
34 |
Chemistry of +1 iodine in alkaline solutionChia, Yuan-tsan. January 1958 (has links)
Thesis (Ph. D. in Chemistry)--University of California, Berkeley, Sept. 1958. / Also issued as UCRL-8311. Includes bibliographical references (leaves 86-87).
|
35 |
The reducing action of a mixture of magnesium iodide (or bromide) and magnesium on aromatic ketones Probable formation of magnesium subiodide (or subbromide) ...Bachmann, Werner Emmanuel, January 1927 (has links)
Thesis (Ph. D.)--University of Michigan, 1926.
|
36 |
The reducing action of a mixture of magnesium iodide (or bromide) and magnesium on aromatic ketones Probable formation of magnesium subiodide (or subbromide) ...Bachmann, Werner Emmanuel, January 1927 (has links)
Thesis (Ph. D.)--University of Michigan, 1926.
|
37 |
The action of sodium triphenylmethyl upon trimethylmethoxy ammonium iodide and of triphenylmethyl halides upon trimethylamine ...Seymour, Merrill Wilmer, January 1928 (has links)
Thesis (Ph. D.)--Princeton University, 1925.
|
38 |
The first general electron transfer reductions of carboxylic acid derivatives using samarium diiodideSpain, Malcolm Peter January 2014 (has links)
The development of new methods for the reduction of carboxylic acid derivatives is described. The ability to reduce these carbonyl derivatives through radical intermediates provides an orthogonal approach as compared with hydride based reductions. Initial experiments focused on the development of the SmI2–H2O system, where we have shown that chelation effects can be utilised to facilitate reduction of cyclic esters. Furthermore, a revised mechanism for the SmI2–H2O mediated reduction of lactones is discussed, and the effective reduction potential of the system determined. Also described is the optimisation of barbituric acids using SmI2–H2O to give the corresponding hemiaminal product. Next, experiments towards the development of a more reactive SmI2-based system are presented; where we have demonstrated that the SmI2–amine–H2O system is capable of the reduction unactivated carboxylic acid derivatives. The reductions of carboxylic esters and acids are described with mechanistic discussions. In addition, the design of a new divalent lanthanide system based on thulium diiodide is described. The addition of proton sources to TmI2 increases the effective reduction potential and facilitates unprecedented reactivity with amides. An investigation into the preparation of the reagent is also described, which has been one of the key factors developing all of the chemistry presented.
|
39 |
Flow cytometry for bioprocess controlWållberg, Fredrik January 2004 (has links)
During bio-technical processing it is important to monitorbiological parameters such as cell growth, viability andproduct formation. Many of the analyses traditionally used areslow to perform and provide only average data for thepopulation. Flow cytometry is a laser-based technique, whichmeasures physical properties of a cell in a flowing stream, ata rate of several thousand cells per second. It offers theprospect of an at-line, multi-parameter analysis of individualmicroorganisms in a population. In this project several methods for at-line measurements ofbioprocesses were developed such as protocol's for measuringcell concentration, viability and product formation. Theprimary focus was on prokaryotic organisms (E. coli) but eukaryotic organisms (P. pastoris) were included. The possibility to use volumetric cell counting to measurecell concentration (cell number) was evaluated. It was shownthat the method was applicable for high cell density processesof bothE. coliandP. pastoris. The combination of Bis- (1,3-dibutylbarbituric acid)trimethine oxonol (depolarised membranes) and propidium iodide(loss of membrane integrity) as fluorescent markers was usefulto measure viability at-line of cells in high cell densityprocesses. The protocol was shown to be reproducible forE. coliandP. pastoris. The viability staining was used to study the kinetics ofweak organic acids (food preservatives). The protocol provideddata about cell functions such as membrane depolarisation andloss of membrane integrity caused by introducing weak organicacids to shake flask cultures ofE. coli. Labeling inclusion bodies with fluorescent antibodiesprovided a method, which could specifically monitor theincreased accumulation of recombinant promegapoetin proteinwith process time. This technique was further developed forintracellular staining by application of a permeabilising stepbefore labeling with antibodies. Staining of inclusion bodiesdirectly inside permeabilised cells gave information about thedistribution of protein expression in the cell population. In conclusion, flow cytometry provides an at-line, singlecell technique for measurement of several biological parametersin bioprocesses. Key words: flow cytometry, Partec PAS, propidium iodide(PI), bis- (1,3-dibutylbarbituric acid) trimethine oxonol(BOX), Alexa fluor 488, bioprocess,E. coli,P. pastoris, inclusion body, food preservatives,viability, membrane potential
|
40 |
The Chlorination of Pharmaceuticals and Other Phenolic Compounds in the Presence of IodideFiss, Edward Matthew 06 May 2009 (has links)
Pharmaceuticals and personal care products (PPCPs) include a wide range of chemicals such as prescription and over-the-counter drugs, fragrances, diagnostic agents, and a litany of other compounds commonly added to household products such as sunscreens, soaps, toothpastes, and deodorants. If present in natural waters, PPCPs can come into contact with disinfectants during drinking water treatment processes. PPCPs are already known to form a variety of disinfection byproducts (DBPs) when oxidized by free chlorine, including trihalomethanes (THMs) and haloacetic acids (HAAs), many of which are known carcinogens.
Salts, such as iodide, are also often present in natural water systems. Iodide is known to form a much more reactive oxidant, free iodine, when it reacts with free chlorine. Free iodine can react with organic compounds in waters to form iodinated byproducts, many of which have been shown to form in higher yields and to be more toxic than their chlorinated analogues. For this reason, it is necessary to more fully understand the fate of PPCPs during drinking water processes. The overall goals of this study are to 1) elucidate reaction mechanisms and product formation potentials for PPCP oxidation by free chlorine in the presence of iodide and 2) develop a computer model that can act as a predictive tool to aid in the assessment of potential risks resulting from PPCPs in source waters.
Through the course of this research, a model was developed that could fit reaction rate parameters and accurately predict solution reactivity for a range of substituted phenols as well as PPCPs including bisphenol-A and triclosan. Past studies utilizing pseudo-first-order rate constants to determine a reaction rate over-simplified the analysis of halogen substitution reactions. Free chlorine reaction rate constant values were updated from the literature since the mechanism for electrophilic substitution was found to be different than stated in currently published literature. The involvement of H₂OCl⁺ was found to be negligible. The mechanism for the electrophilic substitution of phenolic compounds by free iodide was also different from current literature findings. We found that I₂, rather than H₂OI⁺, was an extremely important species for free iodine reactions and must be considered when analyzing the reaction kinetics. Finally, we found that small amounts of iodide can significantly affect product formation pathways thereby causing preferential formation of iodinated products and a potential increase in the total product formation.
In general, the reaction kinetics were highly dependent upon the pH, iodide to free chlorine ratio, and the reactivity of the phenolic compound, and our model was able to successfully address changes in each of these variables. An LFER was developed that showed a linear relationship between reaction rates and the pK<sub>a</sub> of a phenolic compound. It is believed that the model developed can be used as a predictive tool to estimate reactivity of natural waters for a range of phenolic PPCPs simply by using the compounds pK<sub>a</sub>. / Ph. D.
|
Page generated in 0.0364 seconds