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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 (M.S.)--Oregon State University, 1988. / Typescript (photocopy). Includes bibliographical references (leaves 88-93). Also available on the World Wide Web.

Thesis (M.S. in civil engineering)--Washington State University, August 2008. / Includes bibliographical references.

Thesis (Ph. D.)--Oregon State University, 1999. / Typescript (photocopy). Includes bibliographical references (leaves 172-185). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 45-48). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.

Thesis (Ph. D.)--Abo Akademi, 1961. / "This investigation was carried out at the Finnish Pulp and Paper Research Institute, Helsingfors, during the years 1956-1960." Includes bibliographical references ([142]-148).

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2004. / Thesis documentation sheet inserted. Appendix reprints four papers and manuscripts co-authored with others. Includes bibliographical references. Issued also electronically via World Wide Web in PDF format; online version lacks appendix.

The neutral fraction of the petroleum ether extract of Sitka spruce (Picea sitchensis) bark was shown to be rich in compounds of the triterpene class. In particular three monomethyl ether derivatives of triterpene diols were isolated (compounds A, B and C). The structure of the main component, compound A, was proved by methylation studies to be 3β-methoxy-21β-hydroxy-∆¹⁴-serratene (LXXI) and the parent diol, 21-episerratenediol (LIV), and related ketone, 3β-methoxy-21 keto-∆¹⁴-serratene (LVIIa) were also isolated and identified. The other major component, compound B, was shown to have the structure 3α-methoxy-21β-hydroxy-∆¹⁴-serratene (LXXX) by appropriate correlation with known compounds of the serratene series. Compound C is isomeric with A and B but the double bond exists in the fully substituted ∆¹³ position. The most likely structure for this compound is 3α-methoxy-21β-hydroxy-∆¹³-serratene (LXXXI) as shown,by the correlation of its acetate with iso compound B acetate. Two other triterpenes, a ketol, C₃₀H₄₈O₂, and diaxial diol, C₃₀H₅₀O₂, were also isolated but their structures were not conclusively established. A diterpene alcohol, C₂₀H₃₄O, was separated and had spectral properties suggesting its identity with the known compound manool. The extract also contained fatty acid esters of β-sitosterol and presumably of glycerol. The identity of the acids was not investigated. A low melting wax ester was recovered but was not examined in detail. It is interesting to note that the fundamental triterpene skeleton of the above compounds is one in which ring C is seven-membered and only recently have such compounds been obtained in Nature. They undoubtedly present an interesting variation in triterpene biosynthesis. / Science, Faculty of / Chemistry, Department of / Graduate