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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.
1

The scale of influence of substituents in paraffine monobasic acids The divalent oxygen atom,

Hess, Raymond Washington. January 1918 (has links)
Thesis (Ph. D.)--University of Illinois, 1916. / Biographical.
2

The scale of influence of substituents in paraffine monobasic acids The divalent oxygen atom,

Hess, Raymond Washington. January 1918 (has links)
Thesis (Ph. D.)--University of Illinois, 1916. / Biographical.
3

Low molecular weight organic acids in forest soils

Hayden, John 12 November 1999 (has links)
Two studies concerning low molecular weight organic acids in soils were conducted. In the first study, anion exclusion chromatography was used to separate and identify 12 common organic acids, and the accuracy, precision and detection limits of the method were determined. The method was found to be sensitive and accurate to between 1.5 and 9 ��M, depending on the acid in question. The stability of the selected acids was examined, and the large concentration changes observed underscore the importance of timely analysis of soil solutions. No significant interferences were encountered in the analysis of two soil solutions. In the second study, the reaction of a forest soil with oxalic acid at four concentrations was monitored for a period of 96 hours. A large release of aluminum, sulfate, and phosphate was observed, with the greatest release occurring with the highest concentration of added oxalate. Solution aluminum increased by up to a factor of twenty, and though [Al�����] values were consistent with control by thermodynamic equilibrium with an amorphous aluminum oxide phase, exchangeable Al appeared to be the source of the increase. Sulfate increased abruptly at the start of the reaction and continued to rise, though more slowly, throughout the study. Solution phosphate was increased by up to four times and was maintained at the elevated level throughout the study. Changes in both sulfate and phosphate concentrations were attributed directly to exchange with oxalate. The persistence of elevated phosphate concentrations after 96 hours indicates that the effects of oxalate production by mycorrhizae could have lasting effects on the nutrient status of a soil. / Graduation date: 2000
4

Heterogeneous organic acid uptake on soot surfaces

Levitt, Nicholas Paul 15 May 2009 (has links)
Atmospheric particulates have been known to act as cloud condensation nuclei (CCN) and therefore their presence can indirectly affect important processes such as global radiation balance through cloud formation. Soot particles are well known to be atmospheric constituents, but the hydrophobic nature of fresh soot likely prohibits them from encouraging cloud development. Soot aged through contact with oxygenated organic compounds may become hydrophilic enough to promote water uptake. In this study I have observed the interaction between a number of carboxylic acids and soot from different fuel sources and formation mechanisms. A low pressure fast flow reactor was used to control the contact between the solid phase soot and gas phase organics, while chemical ionization-mass spectrometry was utilized to monitor concentrations of gas phase organics. Most acids irreversibly deposited on the soot surfaces, and the uptake coefficient was measured in the wide range of 9.0 x 10-4 to 1.0 x 10-1. The Brunauer, Emmett, and Teller (BET) surface areas of the soots were measured and the soot bulk and surface chemical compositions were investigated with Fourier transform infrared (FTIR) spectroscopy and attenuated total reflection (ATR) spectroscopy to help explain differences in uptake. By comparing the mono and dicarboxylic acids and the information gathered from soot physiochemical properties I have discussed possible uptake mechanisms.
5

Efforts toward the total synthesis of 7-deoxyzaragozic acic A and galtamycinone

Escobar, Maya. January 2002 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
6

Power function determination for sourness and time-intensity measurements of sourness and astrigency for selected acids /

Straub, Angela Marie. January 1989 (has links)
Thesis (M.S.)--Oregon State University, 1992. / Typescript (photocopy). Includes bibliographical references (leaves 152-157). Also available on the World Wide Web.
7

A study of the conductivity and dissociation of organic acids in aqueous solution between zero and thirty-five degrees ...

Wightman, Eugene Pinckney, January 1911 (has links)
Thesis (Ph. D.)--Johns Hopkins University. / Biographical.
8

A study of the conductivity and dissociation of certain organic acids in aqueous solution at different temperatures ...

Springer, Alfred, January 1912 (has links)
Thesis (Ph. D.)--Johns Hopkins University, 1912. / Biographical.
9

The conductivity and dissociation of organic acids in aqueous solution at different temperatures ...

White, George Frederic, January 1910 (has links)
Thesis (Ph. D.)--Johns Hopkins University. / Biographical.
10

A study of the peroxides of organic acids ...

Clover, Alphonso Morton, January 1904 (has links)
Thesis (Ph. D.)--University of Michigan.

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