Search for dissertations about: "internal transport barrier"

Showing result 1 - 5 of 16 swedish dissertations containing the words internal transport barrier.

2. 1. Carrier dynamics in blue and green InGaN LED structures

   Author : Rinat Yapparov; Saulius Marcinkevičius; Ulrich Theodor Schwarz; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; InGaN quantum wells; interwell transport; near-field scanning optical microscopy; internal quantum efficiency; V-defects; InGaN-kvantbrunnar; transport mellan brunnar; optisk mikroskopi med närafältsskanning; intern kvanteffektivitet; V-defekter; Physics; Fysik; Optics and Photonics; Optik och fotonik;

   Abstract : This thesis focuses on effects that are critical to achieving high internal quantum efficiency (IQE) in GaN-based light-emitting diodes (LEDs) that emit in a broad spectral range, from violet to green-yellow. These effects include interwell carrier transport in multiple quantum well (QW) structures, lateral transport in the QW plane, and radiative and nonradiative recombination. READ MORE

4. 2. The intestinal epithelium of salmonids : transepithelial transport, barrier function and bacterial interactions

   Author : Fredrik Jutfelt; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Epithelial barrier function; smoltification; cortisol; osmoregulation; Aeromonas salmonicida; Atlantic salmon; rainbow trout; bacterial translocation; intestine; Ussing chamber; vegetable lipids;

   Abstract : The salmonid intestinal epithelium is important for growth and health of the fish. The epithelium is exposed to a multitude of internal and external factors that can influence its function. READ MORE

5. 3. Alternative methods for analysing moisture transport in buildings : Utilisation of tracer gas and natural stable isotopes

   Author : Kjartan Gudmundsson; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tracer gas; water vapour permeability; diffusion; surface diffusion; isotopic analysis; deuterium; oxygen-18; fractionation; vapour barrier; transient numerical modelling of diffusion; Building engineering; Byggnadsteknik;

   Abstract : New methods, based on tracer gas measurements and isotopicanalysis can be used to evaluate the moisture properties ofbuilding materials and provide the means for forensic analysisof the origins and history of excessive water in buildings, theimmediate practical consequences of which will be the abilityto improve the moisture performance of constructions. It is shown, in theory and through measurements how thewater vapour permeability of porous building materials can witha good degree of accuracy be estimated with tracer gasmeasurements that provide an efficient alternative to the cupmethod. READ MORE

6. 4. Experimental Studies of Charge Transport in Single Crystal Diamond Devices

   Author : Saman Majdi; Jan Isberg; Ricardo S. Sussmann; Uppsala universitet; []
   Keywords : Single crystal diamond; carrier transport; CVD diamond; time-of-flight; mobility; IR detector; compensation; diamond diode; drift velocity; thermal detector;

   Abstract : Diamond is a promising material for high-power, high-frequency and high- temperature electronics applications, where its outstanding physical properties can be fully exploited. It exhibits an extremely high bandgap, very high carrier mobilities, high breakdown field strength, and the highest thermal conductivity of any wide bandgap material. READ MORE

7. 5. 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