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Visar resultat 1 - 5 av 67 avhandlingar som matchar ovanstående sökkriterier.
1. Ionic Transport in Metal Oxides Studied in situ by Impedance Spectroscopy and Cyclic Voltammetry
Sammanfattning : Ionic transport in metal oxides is crucial for the functioning of a broad range of different components, such as heat resistant alloys designed for high temperature applications and oxide electrolytes in solid oxide fuel cells. This thesis presents results from in situ electrochemical studies of properties related to ionic transport in metal oxides that are important for their applications as protective oxides and ionic conductors. LÄS MER
2. Selenium Compounds and Antioxidant Capacity in Bovine Milk. Studies on Glutathione Peroxidase, Bioavailability and Electrochemical Techniques
Sammanfattning : The efficacy and function of antioxidants have been intensively studied in foods and other biological systems in recent decades. This thesis concerns different aspects of the antioxidant properties of bovine milk, with emphasis on measurement of the total antioxidant capacity (TAC), the activity of the selenium-containing glutathione peroxidase (GSHPx), and the bioavailability of selenium from bovine milk in humans. LÄS MER
3. The Impact of Hydrocarbon and Carbon Oxide Impuritiesin the Hydrogen Feed of a PEM Fuel Cell
Sammanfattning : The proton exchange membrane fuel cell generates electricity from hydrogen and oxygen (from air) through electrocatalytic reactions in an electrochemical cell. The Pt/C catalyst, commonly used in PEM fuel cells, is very sensitive to impurities that can interact with the active catalyst sites and limit fuel cell performance. LÄS MER
4. Stepping into Catalysis : Kinetic and Mechanistic Investigations of Photo- and Electrocatalytic Hydrogen Production with Natural and Synthetic Molecular Catalysts
Sammanfattning : In light of its rapidly growing energy demand, human society has an urgent need to become much more strongly reliant on renewable and sustainable energy carriers. Molecular hydrogen made from water with solar energy could provide an ideal case. LÄS MER
5. Ionic and electronic transport in electrochemical and polymer based systems
Sammanfattning : Electrochemical systems, which rely on coupled phenomena of the chemical change and electricity, have been utilized for development an interface between biological systems and conventional electronics. The development and detailed understanding of the operation mechanism of such interfaces have a great importance to many fields within life science and conventional electronics. LÄS MER