Sökning: "hardwood"

Visar resultat 6 - 10 av 82 avhandlingar innehållade ordet hardwood.

1. 6. Ethanol from woodCellulase enzyme production

   Författare :Zsolt Szengyel; Avdelningen för kemiteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical technology and engineering; FPA measurement; acetic acid; furfural; non-volatile; volatile; inhibition; pH; carbon source; liquid; solid; softwood; hardwood; cellulases; production; Kemiteknik och kemisk teknologi; Biotechnology; Bioteknik;

   Sammanfattning : Conversion of biomass to liquid fuels, such as ethanol, has been investigated during the past decades. First due to the oil crisis of the 1970s and lately because of concerns about greenhouse effect, ethanol has been found to be a suitable substitute for gasoline in transportation. LÄS MER

3. 7. New Tools for Analysis of Wood and Pulp Components - Application of MALDI-TOF Mass Spectroscopy and Capillary Zone Electrophoresis

   Författare :Anna Jacobs; KTH; []
   Nyckelord :Capillary zone electrophoresis; carbohydrate composition; degree of acetylation; degree of polymerization; enzymatic hydrolysis; hardwood; hemicellulose; hexenuronic acid; lignin; MALDI-TOF mass spectroscopy; molar mass; molar mass distribution; olig;

   Sammanfattning : In the present thesis, capillary zone electrophoresis (CZE),matrix-assisted laser desorption/ionization time-of-flight massspectroscopy (MALDI-MS) and size-exclusion chromatography incombination with off-line MALDI-MS (SEC/MALDI-MS) have beenapplied successfully to the analysis of wood and pulpcomponents.The carbohydrate compositions of pulp and holocellulosesamples, as well as of isolated hemicellulose preparations,were determined employing enzymatic hydrolysis and subsequentanalysis of the saccharides released by CZE. LÄS MER

4. 8. Characterization of cellulose pulps and the influence of their properties on the process and production of viscose and cellulose ethers

   Författare :Peter Strunk; Bertil Eliasson; Roland Adden; Umeå universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cellulose ether; dissolving pulp; ethyl hydroxyethyl cellulose; hardwood; multivariate data analysis; reactivity; softwood; sulfate; sulfite; viscose;

   Sammanfattning : Today’s market offers an ever-increasing range of cellulose pulps (derivative pulps) made fromvarious wood types through different delignification processes. Each pulp segment has its uniquecharacteristics, which makes it difficult for the producer of cellulose derivatives to choose the mostsuitable pulp for optimum processability and product quality. LÄS MER

5. 9. Carbohydrate degradation and dissolution during Kraft cooking : Modelling of kinetic results

   Författare :Dan Johansson; Ulf Germgård; Pedro Fardim; Karlstads universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Kraft cooking; softwood; hardwood; cellulose; xylan; glucomannan; degradation; dissolution; Chemical engineering; Kemiteknik; Chemical Engineering; Kemiteknik;

   Sammanfattning : Chemical pulp fibres from wood are commonly used in products associated with packaging as well as with printing and writing. The prevalent way of liberating fibres is by subjecting wood chips to Kraft cooking. This process has a history of almost 130 years and should be both well described and well established. LÄS MER

7. 10. Ultrastructural Aspects of Pulp Fibers as Studied by Dynamic FT-IR Spectroscopy

   Författare :Margaretha Åkerholm; KTH; []
   Nyckelord :cellulose; cooperation; crystallinity; dynamic test; glucomannan; hardwood; holocellulose; humidity; infrared spectroscopy; kraft pulp; lignin; mechanical pulp; orientation; polarised light; softwood; strain; sulphite pulp; viscoelasticity; xylan;

   Sammanfattning : Dynamic (or 2D) FT-IR spectroscopy in combination withpolarized IR irradiation has been used in this work to studywood polymer orientation and interactions on theultrastructural level in wood fibers in the native state aswell as the effects of different pulping processes. The woodpolymer interactions were studied under both dry and humidconditions. LÄS MER