Sökning: "dielectric effect"
Visar resultat 1 - 5 av 136 avhandlingar innehållade orden dielectric effect.
1. Structures and Properties of Ferroelectric Liquid Crystal Displays
Sammanfattning : Liquid crystals have unique physical properties as they combine the features of solids and liquids. In thermotropic liquid crystals the degree of order varies with temperature resulting in an appearance of intermediate phases. LÄS MER
2. Enhanced Dielectric Response Methods for the Characterization of Dielectric Materials
Sammanfattning : Dielectric response measurement is widely used for condition assessment of high voltage equipment and for characterizing candidate materials. Measurement with high accuracy and reliability is important in all stages of the lifetime of high voltage equipment, from manufacture to replacement decision. LÄS MER
3. Charge Accumulation in Hybrid High Voltage Insulation
Sammanfattning : This thesis deals with the novel idea of controlling the electric stress or field distribution in a hybrid air - solid-dielectric high voltage insulation by promoting accumulation of surface charges on the internal interfacial layers in the combined (hybrid) dielectric structure. Primarily, applications are expected to be found in high voltage dc systems and as a method to improve the resistance against insulation failure by overvoltages, e. LÄS MER
4. Studies of Dielectric Relaxation in Solid Polymers and Composites
Sammanfattning : Non-linear characteristics of homogeneous solid polymers and solid polymer-based composites have been studied both experimentally and theoretically. In particular experimental studies of non-linear dielectric response of six homogeneous solid polymeric materials and the influence of the composition on the properties of solid polymer-based composites with high dielectric permittivities have been carried out and a theoretical study of dipole-dipole interaction in solids based on a formulation due to P. LÄS MER
5. Electron transport properties of graphene and graphene field-effect devices studied experimentally
Sammanfattning : This thesis contains experimental studies on electronic transport properties of graphene with the Aharonov-Bohm (AB) effect, thermopower (TEP) measurements, dual-gated graphene field effect devices, and quantum Hall effect (QHE). Firstly, in an effort to enhance the AB effect in graphene, we place superconducting-metal (aluminium) or normal-metal (gold) mirrors on the graphene rings. LÄS MER