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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

The chemistry and metabolic significance of acetopyruvic acid

Lehninger, Albert L. January 1942 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1942. / Typescript (carbon copy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographies.
32

The effect of Magnoliac Cortex on acetic acid induced gastric ulcer in rats /

Cheung, Pui-kit, Desmond. January 1999 (has links)
Thesis (M. Med. Sc.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 28-32).
33

Behavior of indicators and other weak bases in acetic acid solutions

Connors, Kenneth A. January 1959 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 92-94).
34

The effect of Magnoliac Cortex on acetic acid induced gastric ulcer in rats

Cheung, Pui-kit, Desmond. January 1999 (has links)
Thesis (M.Med.Sc.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 28-32). Also available in print.
35

The vapor phase equilibrium in the esterification of ethyl alcohol by acetic acid

Brundage, Donald Keith, Halford, Joseph Olney, January 1942 (has links)
From D. K. Brundage's thesis - University of Michigan. / An article, by J. O. Halford and Donald Brundage, reprinted from the Journal of the American Chemical Society, 64, 1942.
36

Phosphine modified rhodium catalysts for the carbonylation of methanol /

Lamb, Gareth William. January 2008 (has links)
Thesis (Ph.D.) - University of St Andrews, May 2008. / Restricted until 29th May 2010.
37

Vinegars Effects on Hemoglobin A1c and Postprandial Glycemia in Individuals at Risk for Diabetes

January 2013 (has links)
abstract: Objective: Vinegar consumption studies have demonstrated possible therapeutic effects in reducing HbA1c and postprandial glycemia. The purpose of the study was to closely examine the effects of a commercial vinegar drink on daily fluctuations in fasting glucose concentrations and postprandial glycemia, and on HbA1c, in individuals at risk for Type 2 Diabetes Mellitus (T2D). Design: Thirteen women and one man (21-62 y; mean, 46.0±3.9 y) participated in this 12-week parallel-arm trial. Participants were recruited from a campus community and were healthy and not diabetic by self-report. Participants were not prescribed oral hypoglycemic medications or insulin; other medications were allowed if use was stable for > 3 months. Subjects were randomized to one of two groups: VIN (8 ounces vinegar drink providing 1.5 g acetic acid) or CON (1 vinegar pill providing 0.04 g acetic acid). Treatments were taken twice daily immediately prior to the lunch and dinner meals. Venous blood samples were drawn at trial weeks 0 and 12 to measure insulin, fasting glucose, and HbA1c. Subjects recorded fasting glucose and 2-h postprandial glycemia concentrations daily using a glucometer. Results: The VIN group showed significant reductions in fasting capillary blood glucose concentrations (p=0.05) that were immediate and sustained throughout the duration of the study. The VIN group had reductions in 2-h postprandial glucose (mean change of −7.6±6.8 mg/dL over the 12-week trial), but this value was not significantly different than that for the CON group (mean change of 3.3±5.3 mg/dL over the 12-week trial, p=0.232). HbA1c did not significantly change (p=0.702), but the reduction in HbA1c in the VIN group, −0.14±0.1%, may have physiological relevance. Conclusions: Significant reductions in HbA1c were not observed after daily consumption of a vinegar drink containing 1.5 g acetic acid in non-diabetic individuals. However, the vinegar drink did significantly reduce fasting capillary blood glucose concentrations in these individuals as compared to a vinegar pill containing 0.04 g acetic acid. These results support a therapeutic effect for vinegar in T2D prevention and progression, specifically in high-risk populations. / Dissertation/Thesis / M.S. Nutrition 2013
38

A study of reaction parameters in the hydrogenation of acetic acid by rhenium heptoxide catalyst

Mylroie, Victor L. 01 August 1968 (has links)
Rhenium oxides as well as other rhenium compounds are known to display a broad spectrum of catalytic activity,^25 being resistant to attack by acids under nonoxidizing conditions, and showing a remarkable ability to resist poisoning which is a serious limiting factor in many commonly used catalysts. Rhenium catalysts are cheaper than the platinum metals with the exception of palladium. One of the most remarkable properties of the rhenium catalyst is the ability to catalyze the hydrogenation of carboxylic acids and amides to the corresponding alcohols and amines respectively. The carboxyl group (-COOH) is notoriously difficult to reduce catalytically and most of the commonly used catalysts are ineffective in catalyzing the hydrogenation of carboxylic acids. Either hydrogenolysis of the carbon-oxygen bond occurs or the carboxylic acid remains inert. It is for this reason that low molecular weight carboxylic acids are often used as inert solvents in catalytic hydrogenations. This investigation was undertaken to study the effects of various parameters upon product formation in the hydrogenation of carboxylic acids using the catalyst formed from the reduction of rhenium heptoxide i situ. Acetic acid was used throughout the investigation as the representative carboxylic acid. The parameters studied were pressures ranging from 2000 to 3000 psig, temperatures ranging from 115° to 175°, reaction time varied over the range of 0 to 24 hours, the effects on product formation from repeated use of the catalyst, and agitation of reactants during the reaction with emphasis on the optimization of these parameters. In several series of reactions repeated reuse of the catalyst showed that rhenium catalyst can be reused at least 8 times while still achieving greater than 50 per cent reduction. Relative decrease in catalyst activity appears to be greater when temperature and pressure of the hydrogenation are high compared to the range. Experimental data shows that the concentration of ethyl acetate in the product mixture as a function of time passes through a maximum between 1.0 and 1.5 hours. Beyond this maximum there is a relatively rapid decrease in ester concentration. A change in initial hydrogen pressure from 2000 to 3000 psig does not appreciably change the product composition in the reaction mixture while a modest increase, i.e., a temperature increase of 25°, was observed to improve yields of the alcohol by a very significant amount. Moreover, the investigation shows that for a reaction time of 5 hours the "optimum" conditions for reaction are a temperature of 175°, a catalyst to substrate ratio of 1.0 g Re_2O_7/50 g AcOH, and an initial hydrogen pressure of 3000 psig while reactions carried out for only 1.5 hours require a catalyst to substrate ratio of from 1.0 to 2.5 g Re_2O_7/50 g AcOH to effect a quantitative reduction optimally. Whether or not the reaction system was agitated during the warm-up period seemed to have little effect on the composition of the product mixture, however, it was observed that partial reduction takes place during the initial heating period before agitation of the reactor begins. The results of this work have shown that "optimum" conditions for quantitative reduction of acetic acid to the corresponding alcohol are the mildest yet reported and clearly confirm the superiority of the rhenium catalyst over other catalysts in the hydrogenation of carboxylic acids.
39

Hydrogenation of aqueous acetic acid to bioethanol over TiO₂-supported Ru-Sn and Ni-Sn catalysts / TiO₂担持Ru-Sn及びNi-Sn触媒による酢酸水溶液のバイオエタノールへの接触水素化分解

Zhao, Yuanyuan 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第23292号 / エネ博第417号 / 新制||エネ||79(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー社会・環境科学専攻 / (主査)教授 河本 晴雄, 教授 石原 慶一, 教授 上髙原 浩 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM
40

Effects of sodium lactate and acetic acid derivatives on the quality and sensory characteristics of hot-boned pork sausage patties

Bradley, Emily McFall 01 May 2010 (has links)
Sodium lactate and acetic acid derivatives were evaluated for their effects on color retention, microbial growth (TPC), oxidation (TBARS), and sensory attributes of hot-boned pork sausage patties that were stored under retail store display conditions over time. Treatments included: (a) 2.5% sodium lactate 60% solids (L), (b) 2.5% buffered vinegar pH 6.5-8.0 (V), (c) 2.5% sodium lactate and vinegar 52/48% mixture (LV), (d) control with 0.02% BHA/BHT (C), and (e) negative control without additives (NC). Overall acceptability of day 17 LV and L treatments were not different (P>0.05) from day 14 treatments. These results revealed that the L and LV sausage patties retained sensory acceptability and microbial quality from day 14 through day 17 as opposed to other treatments. Additionally, sausage patties with 2.5% LV maintained color (redness) and overall acceptability throughout 17 days of shelf-life when held in retail conditions, when compared to other treatments.

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