• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 1
  • Tagged with
  • 258
  • 6
  • 5
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 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.
101

Cellulose modification using ionic liquids

Bell, Thomas James January 2006 (has links)
The aim of this project was to investigate ways of chemically modifying cellulose using ionic liquids. Cellulose is a readily available, naturally occurring, polymeric carbohydrate which is ideal for chemical modification owing to the high density of its functional groups. However, it is insoluble in all common organic solvents. Therefore, interest has recently turned to the use of a novel class of solvents, ionic liquids, which have been found to dissolve cellulose. Initially, studies were undertaken into the acylation of simple carbohydrates using a Lewis acidic choline based ionic liquid, (ZnCl 2)2ChCl. It was found that the yields obtained were comparable to those achieved when traditional solvents and catalysts have been used. It was also found that when only one equivalent of acylating agent was used, all of the carbohydrate hydroxyl groups were acylated. This was thought to be unique to this ionic liquid system. The acetylation of cellulose was also studied in (ZnCl2)2ChCl. Here, it was discovered that the ionic liquid alters the morphology of cellulose by wetting or dissolution thus enabling a range of acetylated products to be produced. Research into the cationic modification of cellulose in an ionic liquid based on chlorcholine chloride (ClChCl) and urea was also undertaken. In this case, it was found that the ionic liquid could act as both the reagent and solvent. It was shown using this system, that all the available (surface) hydroxyl groups on cellulose were modified and that the material produced was significantly more hydrophilic than unmodified cellulose. Finally, preliminary investigations were untaken into other potential surface modifications of cellulose in ionic liquids.
102

Examination of a water-soluble polysaccharide from Polysiphonia fastigiata

Mackenzie, M. E. January 1953 (has links)
No description available.
103

Investigations on fructosans

Telfer, R. G. J. January 1953 (has links)
No description available.
104

The carbohydrate components of quince seed (Cydonia vulgaris)

Buchanan, J. A. January 1952 (has links)
No description available.
105

Studies on galactans with particular reference to Agar

Redhead, J. B. January 1952 (has links)
No description available.
106

Cross-linking of polysaccharides to impart novel functionability

Khondkar, Dristi January 2006 (has links)
No description available.
107

Structural investigations of the polysaccharides of the Chlorophyceae

Mackie, William January 1964 (has links)
No description available.
108

Physicochemical studies on solutions of some plant polysaccharides : the action-pattern of some starch-degrading enzymes

MacGregor, Alexander W. January 1964 (has links)
No description available.
109

Studies of the polysaccharides of white mustard (Sinapis alba)

Richardson, Neil G. January 1965 (has links)
No description available.
110

Formation, melting and interaction of polysaccharide helices

McKinnon, Alan A. January 1973 (has links)
No description available.

Page generated in 0.0157 seconds