Avancerad sökning

Visar resultat 1 - 5 av 61 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Catalysts for Oxygen Production and Utilization : Closing the Oxygen Cycle: From Biomimetic Oxidation to Artificial Photosynthesis

   Författare :Erik Karlsson; Jan-Erling Bäckvall; Björn Åkermark; Jerker Mårtensson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxygen; catalytic oxidation; biomimetic oxidation; artificial photosynthesis; water oxidation; DFT calculations; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

   Sammanfattning : This thesis describes the development and study of catalysts for redox reactions, which either utilize oxygen or hydrogen peroxide for the purpose of selectively oxidizing organic substrates, or produce oxygen as the necessary byproduct in the production of hydrogen by artificial photosynthesis.The first chapter gives a general introduction about the use of environmentally friendly oxidants in the field of organic synthesis, and about the field of artificial photosynthesis. LÄS MER

3. 2. Design and Operation of a 10 kWth Chemical-Looping Combustor for Solid Fuels

   Författare :Nicolas Berguerand; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Solid Fuel Conversion; Chemical-Looping Combustion; Oxygen Carrier; Ilmenite; Carbon Dioxide Capture; Oxygen Transfer; Gas Conversion; Oxygen Demand;

   Sammanfattning : Chemical-looping combustion (CLC) is a new fuel conversion technology with inherent CO2 capture. In this process, the fuel and the combustion air are never mixed and the oxygen is transferred to the fuel via an oxygen carrier in the form of a metal oxide circulating between two reactors, e.g. LÄS MER

4. 3. Catalysts for Car Exhaust: Oxygen Storage in Platinum/Ceria and Mass Transfer in Monoliths

   Författare :Anna Holmgren; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; car exhaust; catalysis; flow distribution; mass transfer; oxygen storage capacity OSC ; ceria; computational fluid-dynamics simulations; monolith catalyst; platinum; oxygen transport;

   Sammanfattning : In this work, the oxygen storage/release in Pt/ceria catalysts has been investigated both experimentally and theoretically. Moreover, the flow distribution and mass transfer in monolith catalysts for car-exhaust purification have been studied. LÄS MER

5. 4. Proton transfer in nitric oxide reducing heme-copper oxidases

   Författare :Joachim Reimann; Pia Ädelroth; Peter Brzezinski; Michael Wilson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; heme-copper oxidases; nitric oxide; proton transfer; electron transfer; proton-transfer pathway; Biochemistry; biokemi;

   Sammanfattning : Heme-copper oxidases (HCuOs) are best known as terminal oxidases in the aerobic respiratory chain, in which they catalyze the reduction of oxygen to water. By receiving protons and electrons from opposite sides of the membrane as well as pumping protons, HCuOs contribute to the electrochemical proton gradient over the membrane that can be used for ATP synthesis. LÄS MER

7. 5. Photoinduced Electron and Energy Transfer in Π-Conjugated Systems

   Författare :Melina Gilbert Gatty; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fs spectroscopy; exciton coupling; conjugated porphyrin oligomers; ps spectroscopy; molecular wire; electron transfer; conformational analysis; self‒assembly; anthracene dendrimers; energy transfer; fluorescence anisotropy;

   Sammanfattning : Photosynthesis is a fascinating process that provides food and oxygen. In this thesis, focus is on understanding and controlling the early processes of photosynthesis, namely photoinduced energy and electron transfer. LÄS MER