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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.
91

Über die Verschwelung von Lignin (mit besonderer Berücksichtigung von Schollerlignin)

Schrameck, Henri, January 1944 (has links)
Promotionsarbeit--Eidgenössische Technische Hochschule, Zürich. / Lebenslauf.
92

Quantifizierung von Lignin aus Papierfabriksabwässern mittels Py-GC-MS und UV-VIS

Schiegl, Christian. Unknown Date (has links)
Techn. Universiẗat, Diss., 2005--München.
93

The cation exchange capacity of plant lignins and soil humic acids

Wildung, Raymond Earle. January 1964 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1964. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 77-82.
94

Reactions of lignin model quinone methides and NMR studies of lignins

Ralph, John. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
95

Destructive distillation of Douglas-fir lignin

Fletcher, Thomas Lloyd, January 1949 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1949. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 66-67).
96

Rate studies of the hydrotropic delignification of aspen wood

Springer, Edward L. January 1961 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
97

Oxygen delignification process chemistry for Acacia

Widiatmoko. January 2006 (has links)
Thesis (M. S.)--Chemical and Biomolecular Engineering, Georgia Institute of Technology, 2007. / Ragauskas, A.J., Committee Chair ; Hsieh, J.S., Committee Co-Chair ; Empie, H., Committee Member.
98

Novel sulfated 4-hydroxycinnamic acid oligomers as potent anticoagulants

Henry, Brian Lawrence, January 1900 (has links)
Thesis (Ph.D.)--Virginia Commonwealth University, 2007. / Title from title-page of electronic thesis. Prepared for: Dept. of Medicinal Chemistry. Bibliography: leaves 255-288.
99

Synthesis and Oxidation of Lignin-Carbohydrate Model Compounds

Nguyen, Mai Thanh Thi January 2008 (has links) (PDF)
No description available.
100

Gold-catalysed oxidation of lignin-derived building blocks

Musharah, Amani January 2016 (has links)
The use of heterogeneous catalysts containing Au nanoparticles supported on TiO2 has been explored for oxidative aqueous phase transformations of sustainable phenolic and benzoic acid derivatives that can be obtained from lignin. Au/TiO2 catalysts were chosen because of their high activity for ambient pressure oxidations of gas phase species, and because their synthesis is facile and reproducible through a modified deposition-precipitation method. The aerobic oxidation of syringic, vanillic, and ferulic acid as well as of guaiacol, eugenol and anisole was investigated at temperatures up to 70°C under (i) atmospheric air sparging in an open reactor and (ii) at 10 atm air pressure in a closed reactor system. The catalysts were characterised by Transmission Electron Microscopy (TEM), Inductively Coupled Plasma (ICP) Optical Emission Spectroscopy and the reproducibility of their catalytic activity independently monitored by determining their activity for carbon monoxide oxidation in a gas flow reactor. The oxidation of syringic acid, vanillic acid, ferulic acid over Au/TiO2 resulted in the formation of 2,6-dimethoxy benzoquinone, guaiacol, and vanillin, respectively, indicating high selectivity for decarboxylation followed by selective oxidation at the position releasing the leaving group. Guaiacol was found to form tetraguaiacol, while eugenol produced quinone methide. Generally, higher air pressure strongly accelerated the transformations, indicating that availability of oxidants formed from O2 is the rate limiting step in the observed transformations. No transformations took place when O2 was excluded from the systems. Overall, guaiacol was found to react fastest, followed by syringic acid, ferulic acid, then vanillic acid. Anisole was found to be unreactive, even at elevated air pressure. The overall reaction pattern emerging from these studies is that the aerobic oxidation in the presence of Au/TiO2 mimics known biotransformations, for example peroxidase-catalysed oxidations involving H2O2.To assess how the functional groups on the aromatic ring influence reactivity the oxidation of p-hydroxybenzoic acid and of 2,6-dimethoxybenzoic acid was also assessed. It was found that decarboxylation of p-hydroxybenzoic acid proceeds, albeit rather slowly, forming phenol, with no further oxidation to hydroquinone or benzoquinone. Taken together these results indicate that the methoxy moieties influence reactivity through both their inductive and resonance effects: leaving of the carboxylic acid group appears to be enhanced through the inductive effect, while further oxidation at the phenolic site seems to be activated through the resonance effect in ortho-position. In line with this hypothesis, it was recently found that dimethoxybenzoic acid converts fast.

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