Thesis (doctoral)--Universität in Leipzig, 1905.

Thesis (Ph. D.)--University of Nebraska. / Includes bibliographical references.

Basel, Math.-naturwiss. Diss., 1921. / Aus: Zeitschrift f. anorgan. u. allgem. Chemie. Bd 121, H. 2., 1922

Thesis (Ph. D.)--University of Chicago, 1916. / Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Chicago, 1915. / Includes bibliographical references. Also available on the Internet.

Many important atmospheric processes are determined by the chemical composition of aerosols, including organic material. Dicarboxylic acids are a commonly detected class of organic material in urban, rural, and remote sites across the globe. Understanding the surface behavior of these molecules is imperative in characterizing the atmospheric fate of these molecules in aerosols, especially at an aerosol surface. In fact, little is known about their orientation, solvation, or pH dependence. This dissertation explores in molecular level detail the concentration and pH behavior of low molecular weight dicarboxylic acids at the air/water interface, which is used as a model for an aerosol surface. The solvation of the carboxylic head groups is shown to be dependent upon the length of the alkyl backbone. Indeed, the solvation of the head groups changes dramatically from very weakly solvated to typical surface solvation to near bulk solvation as the backbone increases. The orientation and conformation at the surface is fully explored to explain these differences in solvation. The pH dependence of surface adsorption is characterized, and it is shown that some acids are only surface active if they are fully protonated while others may still be surface active in singly or fully deprotonated forms. Using a combination of vibrational sum frequency spectroscopy (VSFS), surface tension, and computational modeling, the behavior at the air/water interface of four of the most relevant surface-active dicarboxylic acids (malonic, succinic, glutaric, and adipic acid) is completely described. VSFS, a surface specific optical technique, provides details about the solvation, orientation, and number density at the surface while surface tension measurements provide corollary information about the surface density. The use of computational modeling aids and confirms the spectral analysis while also providing molecular level details about the surface adsorption of the acids studied. By investigating the concentration and pH dependence of these molecules, molecular level detail is obtained which enables a complete description of these acids at an air/water interface and provides pertinent surface information on these atmospherically important organic molecules. This dissertation includes both previously published and unpublished co-authored material.

No description available.

Earlier work has shown that Pseudomonas aeruginosa 9027 can oxidize glucose to carbon dioxide and water by way of gluconic, 2-ketogluconic and pyruvic acids. However, it has been found that closely related organisms can phosphorylate gluconic acid. The object of the present work was to isolate the gluconate oxidizing enzyme, to solubilize it, purify it, determine the co-factor requirements and ascertain whether or not any energy was gained or lost by the system during the reaction. Cells harvested from a gluconic acid medium were disintegrated in a 10 kc. Raytheon sonic oscillator. The enzyme which was still attached to the cell particles was solubilized with sodium glycocholate and remaining particles were removed by the addition of 0.30 saturation ammonium sulphate. Nucleoproteins were then removed by the addition of protamine sulphate. Further fractionation with acid and alkaline ammonium sulphate purified the enzyme 200 fold. Finally the enzyme was absorbed on tricalcium phosphate and eluted with M/5 phosphate buffer of pH 7.0. The pH optimum of the purified enzyme was found to be 5.6 while in the whole cells the maximum activity was at pH 7.0. A hydrogen acceptor was necessary for linking the system to atmospheric oxygen; 2,6-dichlorophenolindophenol and pyocyanine were found to be the most efficient acceptors. Ferricyanide poisoned the system, while brilliant cresyl blue was inactive as a hydrogen acceptor. Reaction with methylene blue was slow. Diphosphopyridine nucleotide, triphosphopyridine nucleotide, flavin mononucleotide, flavin adenine dinucleotide, cytochrome c, adenosine diphosphate and adenosine triphosphate had no influence on the enzyme activity. Sodium fluoride, 2,4-dinitrophenol, azide, iodoacetate, arsenite or 8-hydroxyquinoline did not act as inhibitors. Cyanide, glutathione and cysteine activated the enzyme slightly. The enzyme is specific for gluconic acid. Glucose, glucuronic acid, 2-ketogluconic acid, pyruvic acid, saccharic acid, ribonic acid, arabonic acid, fructose, mannose, ribose-5-phosphate, glucose-6-phosphate or 6-phosphogluconic acid were not oxidized by the enzyme. No carbon dioxide was evolved during the oxidation of gluconic acid by the enzyme. The product on chromatographic analysis, was found to be 2-ketogluconic acid. The enzyme was routinely stored at -10°C in M/10 tris buffer, pH 7.0. Under these conditions it was stable for several weeks. At 4°C, under the same conditions, the enzyme may be kept for three to four days without any appreciable loss of activity. When dialyzed against distilled water, there was a gradual loss of activity after eight to ten hours, accompanied by precipitation. Dialysis against neutral buffers for as long as 24 hours in the cold produced no loss in activity. Instead of sodium glycocholate, "Cutscum" can be used, for solubilizing the enzyme. Purification can also be effected from the sonicate through the use of the ultracentrifuge. The supernatant left after one hour of centrifugation at 105,000 x G oxidized gluconic acid in the presence of pyocyanine and showed two peaks in the electrophoretic apparatus, one of which is believed to be due to protamine sulphate. Though no phosphorylation of the substrate was demonstrable as evidenced by the lack of activation by ATP and the lack of inhibition by fluoride, the problem was further investigated in the sonic extracts. No increase in acid was found either aerobically or anaerobically in P. aeruginosa as tested by the method of Colowick and Kalckar. Moreover, sonic extracts failed to reduce TPN in the presence of gluconate and an excess of phosphogluconic dehydrogenase isolated from Brewer's yeast. In contrast to these data, it was found that by either of the last two mentioned criteria, P. fluorescens A. 312 did phosphorylate gluconate. p. fluores-cens thus possesses an additional phosphorylated pathway for dissimilating glucose and this is absent in P. aeruginosa. No energy was found to be produced in the initial stages of glucose oxidation. The system could not be coupled to the "zwischenferment" reaction of glucose which requires ATP. Chromatographic analysis failed to show any ATP formed during the oxidation of gluconic acid. The significance of these findings in the light of the glucose metabolism by P. aeruginosa is discussed. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate

Difluorophosphoric acid was purified by a double distillation technique. Alkali metal difluorophosphates were prepared by reaction of the metal chlorides with purified difluorophosphoric acid; x-ray powder photographs and infra-red spectra of the salts were obtained. Electrical conductivity measurements were made on solutions of the alkali metal difluorophosphates in difluorophosphoric acid as solvent. The order of mobility of the alkali metal cations in this solvent was found to be Li>Na>K>Rb>Cs. Results indicate that the difluorophosphate ion does not conduct by a proton transfer process in this solvent. Conductimetric studies on solutions of a number of other compounds in difluorophosphoric acid are also reported. / Science, Faculty of / Chemistry, Department of / Graduate

The objective of this study was to establish conditions for the selective periodate oxidation of sialic acid, and then use these conditions to develop a series of general methods for the simultaneous visualization of "neutral sugars" (ie. hexose, 6-deoxyhexose and N-acetylhexosamine) and sialic acid and its side chain O-acyl substituted variants, or O-sulphate ester. Investigations of selective conditions for the oxidation of sialic acids demonstrated that oxidation for one hour at 4°C with 0.4 mM periodic acid in approximately 1M hydrochloric acid (PA*) oxidized all available sialic acid residues of both the sialo and sialosulphoglycoproteins of human and rat colon and the sialoglycoproteins of rat sublingual gland. These conditions produced no visible Schiff staining of either neutral macromolecules or vicinal diols located on the "neutral sugars" of sialo and sialosulphoglycoproteins, and did not result in the extraction of epithelial glycoproteins or in the de-O-acylation of side chain substituted sialic acid residues. Therefore, PA* can be used as a specific reagent for the selective oxidation of sialic acids. Studies of the mechanism of oxidation with PA* showed that the lack of PAS reactivity of "neutral sugars" was not due to the production of Schiff unreactive hemiacetals or hemialdals. It is possible that the selective oxidation of sialic acids with PA* results from an increase in the oxidation rate of sialic acid residues together with a decrease in the oxidation rate of "neutral sugars". Based upon this method for the selective oxidation of sialic acid residues (PA*), five new methods have been devised for the simultaneous visualization of "neutral sugars" and either sialic acid and it side chain 0-acyl derivatives or O-sulphate ester. The first of these is the selective periodate oxidatlon-borohydride reduction-saponification-selective periodate oxidation-thionin Schiff-saponification-borohydride reduction-periodic acid-Schiff (PA*/Bh/KOH/PA*/T/KOH/Bh/PAS) technique, in which sialic acids with O-acyl substituents at C7, C8, or C9 (or which have two or three side chain O-acyl substituents) stain blue while "neutral sugars" with periodate sensitive vicinal diols stain magenta. In the second method, the saponification-selective periodate oxidation-thionin Schiff-saponification- borohydride reduction-periodic acid-Schiff (KOH/PA*/T/KOH/Bh/PAS) method all sialic acids stain blue while "neutral sugars" stain magenta. In the third method, the selective periodate oxidation-thionin Schiff-borohydride reduction-periodic acid-Schiff-saponification (PA*/T/Bh/PAS/KOH) method, sialic acids without side chain substituents or which have an O-acyl substituent at C7 stain blue while "neutral sugars" stain magenta. In the fourth method, the saponification-selectlve periodate oxidation-borohydride reduction-alcian blue PH 1.0-periodic acid-Schiff (K0H/PA*/Bh/AB1.O/PAS) technique, O-sulphate esters stain aquamarine blue while "neutral sugars" stain magenta. In all of these techniques, mixtures of the components stain in various shades of purple. In the fifth and final method, the saponification-selective periodate oxidation-borohydride reduction-periodic acid-Schiff (KOH/PA*/Bh/PAS) technique, selective identification of "neutral sugars" in macromolecules which also contain sialic acids can be achieved. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate