Search for dissertations about: "Reactive Element"

Showing result 1 - 5 of 69 swedish dissertations containing the words Reactive Element.

  2. 1. Adaptive Finite Element Methods for Reactive Flow Problems

    Author : Robert Sandboge; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; convection-diffusion-reaction problems; posteriori error estimates; adaptive finite element methods; ; adaptive finite element methods;

    Abstract : We present and analyze adaptive finite element methods with reliable and efficient error control for a variety of convection-diffusion-reaction problems. The adaptive methods are based on a posteriori error estimates, where the error is estimated in terms of the residual of the computed solution, the mesh size and multiplicative factors measuring certain stability properties of an associated linearized dual problem. READ MORE

  4. 2. Improved Oxidation Resistance and Reduced Cr Vaporization from Thin-Film Coated Solid Oxide Fuel Cell Interconnects

    Author : Hannes Falk Windisch; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 18O-Tracer exposure; Reactive Element; Coating; SOFC; Cr Vaporization; Interconnect; Corrosion;

    Abstract : High electrical efficiency, clean emissions, and the possibility to operate on a great variety of fuels, such as hydrogen, alcohols and hydrocarbons are some advantages of Solid Oxide Fuel Cell (SOFC) technology. Too short lifetimes and high production costs have, however, limited the commercialization of this technology. READ MORE

  5. 3. Phosphorus removal in reactive filter materials : factors affecting the sorption capacity

    Author : Charlotte Nilsson; Gunno Renman; Lena Johansson Westholm; Aleksandra Drizo; Annelie Hedström; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Phosphorus is an essential component in all living organisms; it is one of the components of the DNA and the key element in the energy supplying molecule adenosine triphosphate (ATP). Throughout the history, humans have been recycling phosphorus to agriculture; thereby increasing the yield, examples of this includes the burning of plants and the use of manure. READ MORE

  6. 4. The rule of hydrogen and rare earth metals in the formation of protective metal-oxides

    Author : Bent N. Tveten; KTH; []
    Keywords : chromium; high-temperature corrosion; oxide growth; scale adherence; hydrogen; yttria; REM; reactive element effect; gas phase analysis;

    Abstract : The effects of hydrogen and rare earth metal (REM) additionson the oxidation behavior of metals and alloys that formchromia, alumina and zirconia in 20 mbar O2and/or H2O have been investigated at elevated temperatures.The metal-gas reactions were studied by the use of isotopicallylabeled gas in combination with mass spectrometry and bymeasuring changes in the total pressure in a closed reactionchamber. READ MORE

  7. 5. Sputtering and Characterization of Complex Multi-element Coatings

    Author : Erik Särhammar; Tomas Nyberg; Ulf Jansson; Urban Wiklund; Gustaf Sjöblom; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; thin film; coating; magnetron sputtering; modelling; tribofilm; tungsten disulphide;

    Abstract : The thin film technology is of great importance in modern society and is a key technology in wide spread applications from electronics and solar cells to hard protective coatings on cutting tools and diffusion barriers in food packaging. This thesis deals with various aspects of thin film processing and the aim of the work is twofold; firstly, to obtain a fundamental understanding of the sputter deposition and the reactive sputter deposition processes, and secondly, to evaluate sputter deposition of specific material systems with low friction properties and to improve their performance. READ MORE