Sökning: "Model Cellulose"

Visar resultat 1 - 5 av 182 avhandlingar innehållade orden Model Cellulose.

  1. 1. The kinetics of cellulose enzymatic hydrolysis : Implications of the synergism between enzymes

    Författare :Priit Väljamäe; Jan-Christer Janson; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; Acetobacter; Cellobiohydrolase; Cellobiose; Cellulase; Cellulose; Diffusion; Endoglucanase; Hydrolysis; Inhibition; Kinetics; Model; Product; Substrate; Surface; Synergism; Trichoderma reesei; Biokemi; Biochemistry; Biokemi; biokemi; Biochemistry;

    Sammanfattning : The hydrolysis kinetics of bacterial cellulose and its derivatives by Trichoderma reesei cellulases was studied. The cellulose surface erosion model was introduced to explain the gradual and strong retardation of the rate of enzymatic hydrolysis of cellulose. LÄS MER

  2. 2. Experimental study of alkalinisation of cellulose in industrial relevant conditions

    Författare :Diana Carolina Reyes Forsberg; Ola Sundman; Bertil Eliasson; Ulf Germgård; Umeå universitet; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Mercerisation; Alkalinisation; Cellulose I; Cellulose II; Alkali cellulose; Viscose; Cellulose ether; Carboxymethylcellulose; Sodium glycolate; Sodium diglycolate; Raman spectroscopy;

    Sammanfattning : Mercerisation of cellulose pulp with a solution of NaOH is the first step of manufacturing cellulose-based value-added products, e.g. viscose fibres and cellulose ethers. During this process, cellulose transforms into a swollen crystalline structure, alkali cellulose (Na-Cell). LÄS MER

  3. 3. Countercurrent operation in the dilute-acid hydrolysis of cellulose for ethanol production

    Författare :Pär Pettersson; Institutionen för kemiteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; model; lignocellulose; wood; cellulose; ethanol production; dilute-acid hydrolysis; countercurrent; Kemiteknik och kemisk teknologi; Chemical technology and engineering;

    Sammanfattning : Fuel ethanol can be produced from lignocellulosic materials to replace gasoline and diesel. A crucial step in the production process is the hydrolysis (saccharification) of the material, which can be achieved with dilute acid at high temperature. Unfortunately, sugar is degraded under these severe conditions, and the sugar yield is generally low. LÄS MER

  4. 4. Swelling of Cellulose Fibrillar Matrices and Gels

    Författare :Pernilla Karlsson; Lars Wågberg; Per Tomas Larsson; Eero Kontturi; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; swelling; hydrogel; cellulose; wood; cellulose fibrils; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : One of the major challenges of today´s society is to find a sustainable way to create a living based on the resources on earth. It is a challenge that includes a transition from fossil-based materials to renewable/biodegradable raw materials and also the creation of an environmentally friendly circular material flow. LÄS MER

  5. 5. Nanostructured Cellulose Biocomposites : Effects from dispersion, network and interface

    Författare :Mohd Farhan Ansari; Lars Berglund; Jean-Francois Gerard; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; Wood; cellulose nanofibrils; hygromechanical properties; network structure; thermoset; polymer matrix composites; natural fiber composites; pulp fiber; strain hardening; humidity; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : The major load bearing component in native wood, cellulose nanofibrils, are potential candidates for use as reinforcement in polymer matrices. This study is based on nanocellulose composites and attempts to prepare and characterize biocomposites with high nanocellulose content and investigate the influence of nanostructure on macroscopic properties. LÄS MER