Sökning: "space charge model."

Visar resultat 1 - 5 av 60 avhandlingar innehållade orden space charge model..

  1. 1. Topographical Impact on Space Charge Injection, Accumulation and Breakdown in Polymeric HVDC Cable Interfaces

    Författare :Espen Doedens; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; interfaces; XLPE; roughness; cable peelings; polymer surfaces; space charge; field enhancement factor; PEA; DC breakdown; extruded cable; roughness enhanced charge injection; HVDC; charge injection;

    Sammanfattning : Extruded HVDC cable systems feature a variety of interface types, for which physio-chemical properties will depend on the type of application. Such applications can be joints, terminations or the cable itself, all introducing different material combinations and manufacturing methods. LÄS MER

  3. 2. Acceptor-doped barium zirconate: Oxidation, hydration and space-charge formation

    Författare :Anders Lindman; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; BaZrO3; space charge; point defects; oxidation; GW; hydration; density functional theory; grain boundaries; interatomic potential; perovskites;

    Sammanfattning : The current production and use of fossil fuels is not sustainable and new technologies are needed to become more independent of these fuels.The hydrogen economy, with the fuel cell as an efficient converter of chemical to electrical energy, is a desirable alternative.For this to become a reality, new materials with tailored properties are required. LÄS MER

  4. 3. Solar Wind Proton Interactions with Lunar Magnetic Anomalies and Regolith

    Författare :Charles Lue; Yoshifumi Futaana; Stas Barabash; Urs Mall; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; the Moon; solar wind; magnetic anomalies; regolith; space physics; plasma physics; particle-surface interactions; mini-magnetospheres; energetic neutral atoms; Space Physics; rymdfysik;

    Sammanfattning : The lunar space environment is shaped by the interaction between the Moon and the solar wind. In the present thesis, we investigate two aspects of this interaction, namely the interaction between solar wind protons and lunar crustal magnetic anomalies, and the interaction between solar wind protons and lunar regolith. LÄS MER

  5. 4. A Theoretical Study of Charge Transport in Molecular Crystals

    Författare :Elham Mozafari; Sven Stafström; Magnus Johansson; Linköpings universitet; []
    Nyckelord :Molecular Crystals; Charge transport; Polaron; Holstein model; Peierls coupling;

    Sammanfattning : The main objective of this thesis is to provide a deeper understanding of the charge transport phenomena occuring in molecular crystals. The focus is on the stability and the dynamics of the polaron as the charge carrier.To achieve this goal, a series of numerical calculations are performed using the semi-emprical "Holstien-Peierls" model. LÄS MER

  7. 5. Fragmentation cross sections: measurement, systematics and model developement

    Författare :Chiara La Tessa; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; projectile total charge-changing cross sections; weak factorization; strong factorization; projectile partial charge-changing cross sections; heavy-ions; space radioprotection; nuclear fragmentation;

    Sammanfattning : Man's attitude towards space exploration has been mainly limited by the health risk related to the exposure to the space radiation environment. Some components of the space field can be characterized by such a high flux to kill a man if directly exposed and in general, all space radiation constitutes a hazard for astronauts engaged in long-term missions. LÄS MER