Sökning: "pore size distribution"

Visar resultat 6 - 10 av 92 avhandlingar innehållade orden pore size distribution.

1. 6. Enzyme immobilization in mesoporous silica

   Författare :Hanna Gustafsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pH probe; Mesoporous silica; particle morphology; immobilization; pore size; quartz crystal microbalance with dissipation monitoring; enzyme; biocatalysis;

   Sammanfattning : Enzymes are highly effective and versatile biological catalysts, with a high chemo-, stereo- and regioselectivity while operating under mild conditions, such as physiological temperature and pH and atmospheric pressure. Therefore, enzymes are a sustainable alternative to conventional catalysts in organic synthesis processes. LÄS MER

3. 7. Physico-Chemical Properties of Plant Polysaccharides Investigated with NMR Techniques

   Författare :Åsa Östlund; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NMR diffusometry; Dissolution of cellulose; Chemical shift imaging; Fiber hornification; Xylan; Molecular weight; Pore size distribution; Cryoporometry; Cellulose solution; 19F NMR; Gelation of cellulose; Self-diffusion; Pulsed field gradient NMR; TBAF DMSO; 1H NMR;

   Sammanfattning : In the lead of developing new biomaterials from plant sources it is of importance to be able to control and vary the properties, such as flexibility, strength, and hygroscopicity of the final material. These properties are highly directed by the interactions between constituents on a molecular level. LÄS MER

4. 8. Porous polymeric materials for chromatography : Synthesis, functionalization and characterization

   Författare :Emil Byström; Knut Irgum; Camilla Viklund; Solomon Tesfalidet; Klaus K Unger; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; porous polymer monolith; pore size distribution; nitrogen sorptiometry; mercury intrusion porosimetry; scanning and transmission electron microscopy; plasma functionalization; Analytical chemistry; Analytisk kemi; Separation methods; Separationsmetoder; Polymer chemistry; Polymerkemi; analytisk kemi; Analytical Chemistry;

   Sammanfattning : Background: Separation science is heavily reliant on materials to fulfill ever more complicated demands raised by other areas of science, notably the rapidly expanding molecular biosciences and environmental monitoring. The key to successful separations lies in a combination of physical properties and surface chemistry of stationary phases used in liquid chromatographic separation, and this thesis address both aspects of novel separation materials. LÄS MER

5. 9. Numerical models for degradation of concrete in hydraulic structures due to long-term contact with water

   Författare :Daniel Eriksson; Anders Ansell; Richard Malm; Erik Nordström; Katja Fridh; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; degradation; deterioration mechanisms; hydraulic structures; air-entrained concrete; multiphase model; long-term moisture conditions; pore size distribution; freezing; partially saturated; finite element method; Civil and Architectural Engineering; Byggvetenskap;

   Sammanfattning : The durability of concrete is of major concern in all types of concrete structures where the combined effect of exposure conditions and the type and quality of the concrete material usually determines the rate of degradation. Furthermore, there are synergy effects between different deterioration mechanisms, which means that the combined rate of degradation is higher than the sum of the individual rates of each mechanism. LÄS MER

7. 10. Modeling of Hindered Diffusion in Gels

   Författare :Jan Gutenwik; Avdelningen för kemiteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; effective diffusion coefficient; pore size distribution; obstruction; immobilization; modeling; adsorption kinetics; hindered diffusion; simulation program; proteins; Chemical technology and engineering; Kemiteknik och kemisk teknologi;

   Sammanfattning : Hindered diffusion occurs in the most different processes, as has been described in this thesis. It is very important to have an understanding of the influence of hindered diffusion on the mass transfer rate, especially when competing rate processes are acting simultaneously. LÄS MER