Search for dissertations about: "Mass-transport losses"

Showing result 1 - 5 of 8 swedish dissertations containing the words Mass-transport losses.

2. 1. Critical potential and oxygen evolution of the chlorate anode

   Author : Linda Nylén; Göran Lindbergh; Yohannes Kiros; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; chlorate; chloride oxidation; oxygen evolution; critical anode potential; chromate; DSA; mass transport; RDE; Chemical engineering; Kemiteknik;

   Abstract : In the chlorate process, natural convection arises thanks to the hydrogen evolving cathode. This increases the mass transport of the different species in the chlorate electrolyte. There is a strong connection between mass transport and the kinetics of the electrode reactions. READ MORE

4. 2. Insulation materials in district heating pipes : Environmental and thermal performance of polyethylene terephthalate and polyurethane foam

   Author : Sara Mangs; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; HFC-365mfc; insulation; District heating pipe; 3-pentafluorobutane; cyclopentane; 3; 1; mass transport; 1; 1; thermal performance; polyurethane foam; polyethylene terephthtalate foam;

   Abstract : District heating can contribute to increased energy efficiency in society. The environmental impact can be reduced by minimising the heat losses in the district heating pipes during distribution of the heat to the customers. READ MORE

5. 3. Electrode degradation in proton exchange membrane fuel cells

   Author : Alejandro Oyarce; Göran Lindbergh; Carina Lagergren; Steven Holdcroft; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PEMFC; PEFC; Porous electrodes; Carbon corrosion; Carbon nanotubes; Carbon fibers; Polyhedral carbon nanofoams; Phosphonated hydrocarbon ionomer; Mass-transport losses; Electrode morphology; Electrode collapse; Start-up and shut-down; System strategies; Stainless steel; Bi-polar plates; In-situ contact resistance.;

   Abstract : The topic of this thesis is the degradation of fuel cell electrodes in proton exchange membrane fuel cells (PEMFCs). In particular, the degradation associated with localized fuel starvation, which is often encountered during start-ups and shut-downs (SUs/SDs) of PEMFCs. At SU/SD, O2 and H2 usually coexist in the anode compartment. READ MORE

6. 4. A Study of Catalytic Ignition and Kinetic Phase Transitions

   Author : Mats Rinnemo; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; catalytic ignition; catalysis; kinetic phase transitions; platinum;

   Abstract : Catalytic ignition and kinetic phase transitions are two critical phenomena which can occur in heterogeneously catalyzed reaction systems. They have in common that the system behavior changes qualitatively when a control parame-ter passes through a critical value. READ MORE

7. 5. Lignin Exraction from Black Liquor: Precipitation, filtration and washing

   Author : Henrik Wallmo; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Lignin; Filtration; Separation; Black liquor; Precipitation; Washing.; Absorption;

   Abstract : Lignin extraction is a very interesting option for pulp mills today. Lignin is one major component, present as a dissolved organic compound, in black liquor, which is a by-product in the alkaline pulping of wood. After the digestion of wood chips, the black liquor is separated from the cellulose. READ MORE