Five cation exchange membranes and four anion exchange membranes were tested in a three-compartment, two-membrane, electrolysis salt-splitting cell for the recycle of sodium sulfate into sodium hydroxide and sulfuric acid. The cell is further examined using DuPont Nafion 324 cation exchange membrane and Sybron Ionac MA-7500 anion exchange membrane to determine the maximum concentration of sodium hydroxide that can be produced by electrolysis salt-splitting as well as to determine the chief source of inefficiency. The discussion includes recommendations for future electrolysis salt-splitting cells and a mathematical model of the cell is created to determine optimum operating conditions.

This study was undertaken to compare the absorption and retention of copper and zinc when supplemented to exercising horses in the form of sulfate or organic-chelate mineral supplements. Nine mature horses were used in a modified-switchback designed experiment consisting of seven 28-d periods. Horses were fed a diet consisting of 50% coastal Bermudagrass and 50% concentrate. All diets were balanced to meet the energy, protein, calcium and phosphorus requirements for horses performing moderate to intense exercise. Copper and zinc supplementation varied by period. During mineral depletion and repletion periods, horses respectively consumed diets with no supplemental mineral or Cu and Zn supplemented in the sulfate form to provide 100% of NRC (1989) values. In periods 4 and 7, horses were fed diets designed to provide 90% of NRC (1989) values for Cu and Zn supplied in the sulfate or organic-chelate forms. Horses were subjected to a standard exercise test on d 23 of periods 4 and 7 followed by a 4-d total fecal and urine collection. Blood samples were drawn every 28-d for determination of plasma Cu, Zn and ceruloplasmin concentration, and white blood cell counts and Cu,Zn-superoxide dismutase activity were evaluated in periods 4 and 7. Copper and zinc balance was determined from feed, fecal, urine and water samples obtained during the total collections in periods 4 and 7. Copper and Zn intake and fecal excretion were greater (P<0.05) for horses consuming the organic-chelate supplemented diet. Apparent Cu absorption as a percent of intake and retention as a percent of intake were also greater for this group. Plasma Cu, Zn and ceruloplasmin concentration was not different for horses consuming the two mineral supplement forms. White blood cell counts and superoxide dismutase activity were not affected by diet treatment. Formulation error and suspected sample contamination made it difficult to compare absorption and retention of Cu and Zn, but the use of a controlled repletion-depletion diet sequence appeared to be an effective experimental design component.

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Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1940. / The entire thesis text is included in file. Typescript. Illustrated by author. Thesis contains no title page. Thesis title and author determined from printing on thesis binding and "Seventieth Annual Catalog. Missouri School of Mines and Metallurgy, University of Missouri". Title from title screen of thesis/dissertation PDF file (viewed March 9, 2010) Includes bibliographical references (p. 90-100).

Thesis (M. Phil.)--University of Hong Kong, 1999. / Title from title frame. Includes bibliographical references (leaves 154-159).

External sulfate attack is a complex process that can result in concrete structures deteriorating prematurely. This dissertation describes a comprehensive evaluation of factors influencing external sulfate attack and includes both laboratory and field investigations. Significant emphasis was placed on evaluating the sulfate resistance of mortar and concrete containing high-calcium fly ash (Class C fly ash as per ASTM C 618). This investigation showed that these fly ashes generally reduced the sulfate resistance of mortar and concrete, but that sulfate resistance was possible through the incorporation of other supplementary cementing materials (silica fume and ultra fine fly ash) into these mixtures. Another key area of emphasis in this project was the correlation between accelerated laboratory tests and outdoor exposure site performance. The behavior of concrete exposed to various sulfate salts (sodium, magnesium, and calcium) was evaluated, both in static immersion tests and in outdoor sulfate trenches. It was found that the distress outdoors was exacerbated by physical sulfate attack, especially when concrete was exposed to sodium sulfate. It was found that lowering the water-tocementitious ratio (w/cm) and incorporating appropriate dosages of suitable supplementary cementing materials improved resistance to both chemical and physical forms of sulfate attack. Lastly, a comprehensive study of bridges throughout Texas discovered concrete structures suffering from possible external sulfate attack. The use of analytical techniques such as x-ray diffraction (XRD) and scanning electron microscopy (SEM) were used throughout the study to determine the presence of hydration products that may form with mortars and concrete specimens. Findings from this research will be implemented in specifications in Texas for the use of Class C fly ash use in concrete in areas that may have sulfate soils and groundwater.

A previously proposed kinetics equation describing the delignification of wood in soda-anthraquinone (AQ) liquors was shown to be valid under isothermal conditions, and was extended to describe variation in initial alkali charge. Kinetics expressions were derived for soda-amine, kraft (soda-hydrosulfide ion) and soda-ethanol delignification under isothermal conditions over various ranges of additive charge. In each case, the total delignification observed after a given time of pulping could be described as the sum or two contributions: (i) that due to the sodium hydroxide alone, and (ii) that due to the additive (AQ, amine, hydrosulfide ion or ethanol). Rate constants were determined at various temperatures and apparent Arrhenius activation energies were calculated for soda-AQ, soda-amine and kraft delignification. Although the calculated activation energies were found to be similar, the forms of kinetic expressions obtained suggested that the role of AQ in alkaline delignification may differ from that of an amine or hydrosulfide ion. The effects of various combinations of additive pairs on delignification were investigated and the results suggested that interactions occur. Under certain conditions, delignification in soda-AQ-amine and kraft-AQ liquors, respectively, could be described as the sum of the effects of the sodium hydroxide alone, the amine or hydrosulfide ion, and a term dependent upon the anthraquinone.

Thesis (MScIng)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.

Diss. (sammanfattning) Uppsala : Univ., 2004. / Härtill 4 uppsatser.

Thesis (M.S.)--California Polytechnic State University, 2009. / Mode of access: Internet. Title from PDF title page; viewed on April 30, 2009. Major professor: Terry Smith, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Agriculture with a specialization in Soil Science." "March, 2009." Includes bibliographical references (p. 37-40). Also available on microfiche.