Search for dissertations about: "internal contact resistance"

Showing result 1 - 5 of 17 swedish dissertations containing the words internal contact resistance.

  2. 1. On Gas Contaminants, and Bipolar Plates in Proton Exchange Membrane Fuel Cells

    Author : Yasna Acevedo Gomez; Carina Lagergren; Göran Lindbergh; Rakel Wreland Lindström; Qinfeng Li; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PEM fuel cell; contaminants; ammonia; nitrogen dioxide; degradation; recovery; bipolar plates; electroplating; Ni-Mo; Ni-Mo-P; internal contact resistance; PEM bränslecell; föroreningar; ammoniak; kvävedioxid; degradering; återhämtning; bipolära plattor; elektroplätering; Ni-Mo; Ni-Mo-P; interna kontaktmotståndet; Chemical Engineering; Kemiteknik;

    Abstract : The proton exchange membrane (PEM) fuel cell is an electrochemical device that converts chemical energy into electrical energy through two electrocatalytic reactions. The most common catalyst used is platinum on carbon (Pt/C), which has shown the best performance in the fuel cell until now. READ MORE

  4. 2. Biomechanical analyses of flywheel resistance exercise : From a space- and ground-based perspective

    Author : Maria Sjöberg; Ola Eiken; Elena Gutierrez-Farewik; Hans E Berg; Patrik Sundblad; Loren FZ Chiu; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AnyBody Modeling System; concentric; eccentric; eccentric overload; inverse dynamics; knee extensors; microgravity; musculoskeletal deconditioning; net-joint moment; AnyBody Modeling System; excentrisk; excentrisk överbelastning; invers dynamik; knäextensorer; koncentrisk; ledmoment; mikrogravitation; muskuloskeletal nedbrytning; Teknik och hälsa; Technology and Health;

    Abstract : Astronauts suffer degradation of postural muscles and weight-bearing bones during long-duration spaceflight. Resistance exercise is used as a primary countermeasure against these degradations. READ MORE

  5. 3. Alloys in Contact with Molten Salts for Thermal Storage Applications

    Author : Esraa Hamdy Mohamedin; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phase transition; Molten salts; High-temperature corrosion; Alumina-forming alloys; Carburisation; Thermal energy storage TES ; Laves phase; Concentrated solar power CSP ;

    Abstract : The combination of a concentrated solar power (CSP) plant and a thermal energy storage (TES) system is a promising technology for power generation, in that it overcomes the challenges commonly faced by renewable energy systems, such as intermittency, dispatchability, and the gap between the energy supply and energy demand. The third generation (Gen3) CSP plants are designed to increase plant efficiency by using supercritical carbon dioxide (sCO2) instead of steam for the Brayton cycle gas turbines, requiring a minimum operating temperature of 750°C for the TES materials. READ MORE

  6. 4. Frost-induced deterioration of concrete in hydraulic structures : Interactions between water absorption, leaching and frost action

    Author : MARTIN ROSENQVIST; Avdelningen för Byggnadsmaterial; []
    Keywords : Vattenbyggnader; Dammar; Betong; Cement; Vattenabsorption; Vattenmättnadsgrad; Nedbrytning; Frostbeständighet; Spjälkning; Makroskopisk islinsbildning; Urlakning; Synergi; Hydraulic structures; Dams; Concrete; Cement; Water absorption; Degree of saturation; Deterioration; Frost resistance; Spalling; Macroscopic ice lens growth; Leaching; Synergy;

    Abstract : Frost deterioration of concrete can result in severe consequences to the safety, durability and functionality of a structure since it impairs the strength of the concrete. Frost damage may occur to structures that are in contact with water and subjected to frost action. READ MORE

  7. 5. On the Internal Sizing Mechanisms of Paper with AKD and ASA Related to Surface Chemistry, Wettability and Friction

    Author : Rauni Seppänen; Mark Rutland; John Roberts; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Surface and colloid chemistry; Yt- och kolloidkemi;

    Abstract : Paper and board are hydrophobized (sized) to control the spreading and absorption of waterbased inks and retard the absorption and edge penetration of liquid packaging by aqueous liquids. Alkenyl ketene dimers (AKD) and alkenyl succinic anhydride (ASA) are synthetic sizing agents that are generally used under neutral or slightly alkaline papermaking conditions. READ MORE