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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.
21

The possible correlation between hemicelluloses and the physical properties of bleached kraft pulps.

Ratliff, Francis T. (Francis Tenney) 01 January 1948 (has links)
No description available.
22

The physical properties of slash pine semichemical kraft pulp and of its fully chlorited component

Keeney, Frederick Critchfield, January 1952 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1952. / Includes bibliographical references (p. 154-157).
23

An investigation of the role of sodium sulfide in cellulosic chain cleavage during kraft pulping

Blythe, David A., January 1984 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1984. / Includes bibliographical references (p. 83-86).
24

Alkaline degradation of methyl [beta]-D-glucopyranoside and methyl 2-O-methyl-[beta]-D-glucopyranoside

Nault, James J., January 1979 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1979. / Includes bibliographical references (leaves 81-82).
25

Color removal from softwood, kraft, caustic extract effluent by polyamines

Kisla, T. C. January 1976 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1976. / Bibliography: leaves 93-95.
26

A study of the initial phase of the aqueous chlorination of kraft pulp meals

Russell, Norman A., January 1966 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1966. / Bibliography: leaves 82-84.
27

The possible correlation between hemicelluloses and the physical properties of bleached kraft pulps

Ratliff, Francis T. January 1948 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1948. / Bibliography: leaves 78-80.
28

The role of surfactants in kraft pulping of different wood species /

Chen, Dezhi, 1982- January 2007 (has links)
A unique penetration instrument has been developed to evaluate the role of surfactants in kraft pulping process. This instrument can screen surfactants which can improve the wood impregnation more effectively and much faster than pilot-plant experiment. The role of surfactants in wood penetration has been explored. Surfactants can improve wood impregnation by dispersing the extractives in the wood structure and optimizing the interfacial properties between wood surface and kraft liquor. The addition of two blends of anionic and nonionic surfactants into kraft pulping process results in a significant reduction of the screen rejects and an increase of screened yield at the same delignification rate. / Six wood species were tested in this study including both non-resinous and resinous wood species. Both sapwood and heartwood of these species were tested. Surfactants were found to have no improvement on sapwood, but a significant improvement on heartwood. The critical micelle concentrations (CMC) of surfactants in kraft liquor were determined. The best dosages of surfactants based on CMC were also determined in this study.
29

Production of a cloned xylanase gene in Bacillus cereus and its performance in kraft pulp prebleaching

Tremblay, Louis January 1993 (has links)
Xylanase production from a Bacillus subtilis gene cloned into a strain of Escherichia coli was measured. Although this gene was expressed in E. coli at several temperatures, efficient normal xylanase secretion did not occur, the observed protein release apparently depending on cell leakage or lysis. Screening for a better microbial protein secretor free of cellulase selected B. cereus #259. The strain had wild plasmids that were hard to eliminate using acridine orange and elevated temperature curing techniques. While still bearing 5 wild plasmids, attempts to transform B. cereus #259 were unsuccessful using conventional methods and electroporation. Another strain, B. cereus #518, found to be free of wild plasmids, was then used. A bidirectional vector shuttle plasmid (pMK3) was employed to carry the cloned gene into this B. cereus strain. Transformation was carried out by high voltage electroporation. Xylanase production by the new B. cereus clone was similar to that from E. coli, but was shown to be continuously and normally secreted. The xylanase gene products from the E. coli and B. cereus hosts were shown to function identically. Both xylanases improved the delignification of unbleached softwood and hardwood kraft pulps, thus reducing the Cl$ sb2$ required to achieve a given degree of bleaching, without altering the physical properties of the fibers. Using a target kappa number lignin content) of 5, xylanase pretreatment of aspen kraft pulp led to a 22% saving of chlorine. Adsorbable organic halogens in the bleachery effluent were also lowered by more than 50%.
30

Dynamic simulation of the first two stages of a kraft softwood bleach process

Mackinnon, John, 1963- January 1987 (has links)
No description available.

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