Triclosan and triclocarban are antimicrobial compounds added to a variety of consumer products that are commonly detected in waste water effluent. The focus of this study was to determine whether the bioconcentration of these compounds in wetland plants and sediments exhibited species specific and site specific differences by collecting field samples from a constructed wetland in Denton, Texas. The study showed that species-specific differences in bioconcentration exist for triclosan and triclocarban. Site-specific differences in bioconcentration were observed for triclosan and triclocarban in roots tissues and sediments. These results suggest that species selection is important for optimizing the removal of triclosan and triclocarban in constructed wetlands and raises concerns about the long term exposure of wetland ecosystems to these compounds.

Rats fed diets which contained 15% of casein and 0.620% of methionine with 0.0002, 0.02 and 0.42% of dietary inorganic sulfate had a dietary sulfate-related change in methionine metabolism. Rats fed the diets low in sulfate (0.0002%) had a 35% increase in methionine metabolism compared to rats fed the diets high in sulfate (0.42%). In contrast, rats fed the diet low in sulfate (0.0002%) had the lowest level of tissue S-adenosyl-methionine and the highest activity of phenylethanolamine-N-methyltransferase activity. Those animals fed the diet normal with respect to sulfate (0.02%) had intermediate levels of S-adenosylmethionine and phenylethanolamine-N-methyl transferase activity. Rats fed the diet high in sulfate (0.42%) had the highest level of tissue S-adenosyl-methionine and the lowest phenylethanol-amine-N-methyl transferase activity. Due to the inverse relationship between S-adenosylmethionine and phenylethanolamine-N-methyl transferase activity, it appears that the catecholamines may function as a methyl sink for the increase in the metabolism of methionine required to provide sulfate for rats fed diets low in sulfate.

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<p> The acetate-catalyzed bromination of acetone is shown to occur by an enolization mechanism, although the reactions involved in this process are more complex than has been supposed.</p> <p> A study of the activation parameters for the enolization of some bromoacetones, and an observed linear free energy relationship between enolization rate constants, and acid ionization constants, shows that the transition state for this process resembles enolate and not enol.</p> <p> Bromine substitution in ketones accelerates enolization rates on both sides of the carbonyl group.</p> <p> The acetate-catalyzed enolization of 2-butanone favours the methylene group by a factor of nearly two. This fact is interpreted in terms of methyl groups being inductively electron-withdrawing in their effect in forming an enolate transition state.</p> / Thesis / Doctor of Philosophy (PhD)

The complex between Al(III) and 2-methyloxine has been prepared from various aqueous and aqueous-acetone solutions, both in the presence and the absence of acetate ion as an auxilliary complexing agent. The effect of pH on precipitation of the complex from 20% v/v acetone-water medium has been determined. Solid-phase hydrous aluminum oxide has been converted to the tris complex by the addition of a dioxane solution of 2-methyloxine. Infrared spectral evidence has been found for some degree of complexation from reactions in the melt between Al(III) and 2-n-propyl-, 2-n-butyl-, and 2-phenyloxine. / Thesis / Master of Science (MSc)

Oxidative storage stability was conducted to determine the optimum antioxidant for the production of catfish methyl esters (CFME) for use as biodiesel. Peroxide value, anisidine value, 2-thiobarbituric reaction substances, acid value, iodine value, UV absorbance, and induction period were measured. Antioxidant, stability parameters changed over a storage time of one year when stored at 25°C. The CFME were not stable to oxidation without the addition of TBHQ. When stored at 25°C, oxidative parameters indicated that CFME was a stable product that met oxidative stability standards when TBHQ was added. When held at 80°C for 28 days, the samples with TBHQ were stable to oxidation. However, the acid value rose above the maximum at 28 days. Thus, CFME can be stable to oxidative breakdown when THBQ was added at 800 ppm, but when exposed to high temperatures, one will have to limit water or protect CFME against hydrolytic rancidity.

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