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Visar resultat 1 - 5 av 149 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Quantum Dot Solar Cells: Towards Environmentally Friendly Materials

    Författare :Viktor A. Öberg; Erik Johansson; Muhammet S. Toprak; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum dots; Nano-crystals; Energy conversion; Solar cells; Quantum dot solar cells; Low toxicity; Silver Sulfide; Silver Bismuth Sulfide; Lead Sulfide; Chemistry with specialization in Physical Chemistry; Kemi med inriktning mot fysikalisk kemi;

    Sammanfattning : To decrease the world’s energy dependence on fossil fuels, energy production and specifically electricity production needs to shift to more sustainable alternatives. One such alternative is solar cells as they directly convert energy emitted from the sun into electricity. LÄS MER

  3. 2. Experimental studies of radiation-induced dissolution of UO2 : The effect of intrinsic solid phase properties and external factors

    Författare :Alexandre Barreiro Fidalgo; Mats Jonsson; David Shoesmith; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Oxidation; dissolution; uranium dioxide; gadolinium; bentonite; sulfide; hydrogen; gamma radiation; radiolysis; hydrogen peroxide; hydroxyl radical; repository; Kemi; Chemistry;

    Sammanfattning : Dissolution of the UO2 matrix is one of the potential routes for radionuclide release in a future deep geological repository for spent nuclear fuel. This doctoral thesis focuses on interfacial reactions of relevance in radiation-induced dissolution of UO2 and is divided in two parts:In the first part, we sought to explore the effects of solid phase composition:The impact of surface stoichiometry on the reactivity of UO2 towards aqueous radiolytic oxidants was studied. LÄS MER

  4. 3. Interfacing spectrophotometry to process liquors applications to kraft pulping

    Författare :Xiaotian Yang; KTH; []
    Nyckelord :Kraft cooking; On-line; Sulfide; Lignin; Polysulfide excess sulfur; Anthraquinone-2-sulfonate; Anthraquinone; Nafion membrane; UV-Vis; ATR-probe; Spectrophotometric;

    Sammanfattning : This thesis summarizes the outcome of work performed withthe objective to contribute to the knowledge and development ofthe kraft cooking process using spectrophotometricinterfaces.In kraft cooking, it is desirable to maximize the removal oflignin in the cook without loss of pulp strength. LÄS MER

  5. 4. Analysis and speciation of organic phosphorus in environmental matrices : Development of methods to improve 31P NMR analysis

    Författare :Johan Vestergren; Gröbner Gerhard; Jurgen Schleucher; Ulrik Ilstedt; Per Persson; Reiner Giesler; Benjamin L. Turner; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Phosphorus; soil; 31P NMR; NaOH EDTA; terrestrial; sulfide; speciation; bioavailability; paramagnetic; humus; boreal; tropical; multi-dimensional; agroforestry; chronosequence; fysikalisk kemi; Physical Chemistry;

    Sammanfattning : Phosphorus (P) is an essential element for life on our planet. It is central in numerous biochemical processes in terrestrial and aqueous ecosystems including food production; and it is the primary growth-limiting nutrient in some of the world’s biomes. LÄS MER

  7. 5. Profitability = f(G) : Computational Thermodynamics, Materials Design and Process Optimization

    Författare :David Dilner; Malin Selleby; Mao Huahai; André Costa e Silva; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CALPHAD; steel; sulfide; steelmaking; thermodynamics; ICME; CALPHAD; stål; sulfid; ståltillverkning; termodynamik; ICME; Teknisk materialvetenskap; Materials Science and Engineering;

    Sammanfattning : The thesis starts by giving a motivation to materials modeling as a way to increase profitability but also a possibility decrease the environmental impact. Fundamental concepts of relevance for this work are introduced, this include the materials genome, ICME and of course the CALPHAD method. LÄS MER