Sökning: "Catalyst"

Visar resultat 16 - 20 av 784 avhandlingar innehållade ordet Catalyst.

  1. 16. Materials Reliability in PEM Fuel Cells

    Författare :Live Mølmen; Peter Leisner; Ulf Jansson; Jönköping University; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fuel cell; PEMFC; Bipolar plate; Catalyst; Electrodeposition; Corrosion; Stainless steel; Accelerated stress tests; bränsleceller; PEM; bipolära plattor; katalysator; elektroplätering; korrosion; accelererad testning;

    Sammanfattning : As part of the global work towards reducing CO2 emissions, all vehicles needs to be electrified, or fueled by green fuels. Batteries have already revolutionised the car market, but fuel cells are believed to be a key energy conversion system to be able to electrify also heavy duty vehicles. LÄS MER

  3. 17. Metal-exchanged zeolites for NH3-SCR applications - Activity and Deactivation studies

    Författare :Soran Shwan; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; modeling; NOX.; Hydrothermal; Chemical; Kinetic; Copper; Deactivation; Iron; Zeolite; Nitrogen oxides; NH3; Ammonia; Catalyst; NSR; Emissions; Poisoning; Ageing; NH3-SCR;

    Sammanfattning : Emissions of nitrogen oxides (NOX) formed during the burning process in internal combustion engines is a major contributor to global air pollutions. One effective way to reduce NOX in lean environments, i.e. oxygen excess is selective catalytic reduction with ammonia (NH3-SCR). LÄS MER

  4. 18. Selective transfer hydrogenations : Catalyst development and mechanistic investigations

    Författare :Jenny Wettergren; Hans Adolfsson; Serafino Gladiali; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; transfer hydrogenation; transition metal; amino acids; amino alcohols; Organic chemistry; Organisk kemi; Organic Chemistry; organisk kemi;

    Sammanfattning : By generating a library of amino acid-based ligands, pseudo-dipeptides, and combining them with transition metals, we have created selective and efficient ruthenium and rhodium catalysts for the asymmetric transfer hydrogenation of ketones. The ruthenium-catalyzed reaction was studied in detail, and we found that alkali metals play a crucial role for the reactivity and selectivity of the reaction. LÄS MER

  5. 19. Asymmetric transfer hydrogenation of ketones : Catalyst development and mechanistic investigation

    Författare :Katrin Ahlford; Hans Adolfsson; Martin Wills; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Asymmetric catalysis; reduction; amino acid; rhodium; mechanistic investigation; kinetic study; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : The development of ligands derived from natural amino acids for asymmetric transfer hydrogenation (ATH) of prochiral ketones is described herein. In the first part, reductions performed in alcoholic media are examined, where it is found that amino acid-derived hydroxamic acids and thioamides, respectively, are simple and versatile ligands that in combination with [RhCp*Cl2]2 efficiently catalyze this particular transformation. LÄS MER

  7. 20. Zeolite adsorbents and catalysts for the recovery and production of biochemicals

    Författare :Abrar Faisal; Mattias Grahn; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Zeolites; Adsorbents; Catalyst; Butanol; Arginine; ZSM-5; Chemical Technology; Kemisk teknologi;

    Sammanfattning : Fossil based energy resources are dominating the world’s primary energy consumption for the last century. However, with decreasing crude oil reservoirs and the role they play in global warming by emitting greenhouse gases, the focus has been turned towards improved utilization of renewable resources and the need for new, sustainable fuels and chemicals is more urgent than ever. LÄS MER