Search for dissertations about: "permittivity"

Showing result 21 - 25 of 89 swedish dissertations containing the word permittivity.

  2. 21. On the inception and propagation of streamers along mineral-oil/solid interfaces

    Author : David Ariza; Marley Becerra; Olivier Lesaint; KTH; []
    Keywords : ;

    Abstract : This thesis presents an experimental study of positive and negativestreamers propagating along mineral-oil/solid interfaces under square highvoltage pulses. The thesis includes the design and construction of anexperimental setup to studying the streamers in a point-plane configurationcapable to detect streamer parameters such as velocity, length, propagationtime, emitted light and charge. READ MORE

  4. 22. Characterization of (Ba,Sr)TiO3 thin films for multiplier applications

    Author : Pär Rundqvist; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; BSTO; THz; triplers; powerhandling capability; multilayer structures; frequency multipliers; Ferroelectric; BST; losses; Varactor; STO;

    Abstract : (Ba,Sr)TiO3 (BSTO) and SrTiO3 (STO) parallel plate ferroelectric varactors are investigated for microwave multiplier applications.STO and BSTO exhibit low losses, high permittivity and largetunability of both permittivity and losses. All films are deposited using Pulsed Laser Deposition, magnetron sputtering and E-beam evaporation. READ MORE

  5. 23. Effective properties of heterogeneous materials with applications in electromagnetics

    Author : Christian Engström; Institutionen för elektro- och informationsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; homogenization; optics; acoustics; Electromagnetism; structural parameters; anisotropic material; inverse homogenization; Bloch waves; Maxwell s equations; Elektromagnetism; optik; akustik; Inverse bounds;

    Abstract : Composite materials, i.e, mixtures of two or more materials, are commonly used in industry, because they often have outstanding properties in comparison with the original materials. In many cases the inhomogeneities are on a very fine scale, which makes it difficult to perform a full numerical simulation of the material. READ MORE

  6. 24. Evaluation of the Tactoid Formation in Clay Systems

    Author : Maria Jansson; Beräkningskemi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Lera; Montmorillonit; Nano-plattor; Taktoider; Anisotropi; Grov korninga modeller; MD simuleringar; MC simuleringar; SAXS; Svälltryck; Clay; Montmorillonite; Nanoplatelets; Tactoid; Anisotropy; Coarse-grained models; MD simulations; MC simulations; SAXS; Swelling pressure;

    Abstract : Clay minerals consist of anisotropic nanoplatelets where the majority of the clay minerals are highly charged, and thus, swell in aqueous solution. The structure and swelling depend on the type of clay mineral, and also on the ionic composition, and temperature. READ MORE

  7. 25. A Microwave Tomography Framework for Monitoring of Pharmaceutical Processes

    Author : Livia Cerullo; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sensitivity Analysis; Microwave Tomography; Reconstruction Algorithm; Parameterization; Pharmaceutical Processes;

    Abstract : Industrial pharmaceutical processes may be very difficult to monitor and control. Today, an important research fields is non-invasive measurement techniques that provide information about thematerial distribution inside the process. In this thesis, a microwave tomography (MWT) framework for monitoring of pharmaceutical processes is presented. READ MORE