Search for dissertations about: "insulating materials"

Showing result 21 - 25 of 120 swedish dissertations containing the words insulating materials.

  2. 21. Charge transport in polymer-based insulating materials for high voltage applications: effect of single- and multi-layered structures

    Author : Tuan Anh Hoang; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; charge trapping and de-trapping; polyethylene; surface potential decay; enamel insulation; charge transport; charging current; charge injection; charge mobility; DC conductivity; nanocomposite;

    Abstract : Polymer composites have been widely employed as electrical insulating materials for high voltage components and devices such as power cables, gas-insulated systems, rotating machines, line and post insulators, etc. Such materials are usually made by introducing inorganic oxides (SiO2, TiO2, Al2O3, MgO) into polymeric matrices e.g. READ MORE

  4. 22. Electrical properties of polycrystalline silicon

    Author : Matts Rydberg; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Materialvetenskap; Materials science; Teknisk materialvetenskap; Elektronik; Electronics;

    Abstract : Polysilicon is used, among other materials, in today's integrated circuits. In this thesis, the structural and electrical properties' of polysilicon thin film resistors have been studied. The aim has been to improve the long-term stability and increase the knowledge concerning grain-boundary related phenomena. READ MORE

  5. 23. Electrical Transport in Nanoparticle Thin Films of Gold and Indium Tin Oxide

    Author : Jesper Ederth; Knut Deppert; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Electrical transport; Nanoparticle; Nanocrystalline; Materialvetenskap; Materials science; Teknisk materialvetenskap; English; engelska;

    Abstract : Electrical transport properties of nanoparticle gold films made by the gas evaporation method were analysed using resistivity measurements. Low temperature electrical transport measurements showed a cross-over from a temperature range dominated by inelastic scattering to a temperature range dominated by elastic scattering, presumably by grain boundaries. READ MORE

  6. 24. On Surface Characteristics and Microstructural Development of Soft Magnetic Composite Powder and Components

    Author : Christos Oikonomou; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; X-ray photoelectron spectroscopy; compaction; annealing; X-ray diffraction; soft magnetic composites; high resolution scanning electron microscopy; surface layers; magnetic testing; powder metallurgy; depth profiling; electron backscatter diffraction; focused ion beam; thickness determination; energy dispersive X-ray spectroscopy; microstructure;

    Abstract : Soft Magnetic Composite (SMC) products manufactured by traditional Powder Metallurgical (PM) techniques, are strong candidate materials for electromagnetic applications. Their advantages are based on cost and energy efficient production methods, shape complexity realization and uniquely uniform and isotropic three dimensional (3D) magnetic properties. READ MORE

  7. 25. Renewable and Scalable Energy Storage Materials Derived from Quinones in Biomass

    Author : Lianlian Liu; Olle Inganäs; Niclas Solin; Daniel Brandell; Linköpings universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; renewable; scalable; quinones; energy storage;

    Abstract : Currently there is an urgent need to reduce the use of fossil fuels, and efficient sustainable energy harvesters from sun and wind have been developed and are widely used for electricity generation. Storage of electrical energy is accordingly necessary to accommodate the time varying supply of wind and solar electricity. READ MORE