Sökning: "Acid catalyst"

Visar resultat 21 - 25 av 147 avhandlingar innehållade orden Acid catalyst.

  1. 21. Direct Catalytic Nucleophilic Substitution of Non-Derivatized Alcohols

    Författare :Anon Bunrit; Joseph Samec; Joseph Moran; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nucleophilic substitution; catalysis; alcohols; stereospecific; Lewis acid; Brønsted acid base; bifunctional; heterocycles; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis focuses on the development of methods for the activation of the hydroxyl group in non-derivatized alcohols in substitution reactions. The thesis is divided into two parts, describing three different catalytic systems. LÄS MER

  3. 22. Nanostructured Fuel Cell Catalysts

    Författare :Marie Gustavsson; Chalmers tekniska högskola; []
    Nyckelord :Nafion; thin film evaporation; model catalyst; electrocatalyst; acetic acid oxidation; oxygen reduction; colloidal lithography; PEMFC; screening; Pt; formaldehyde oxidation; methanol oxidation; nanofabrication; CO oxidation; polymer electrolyte; TiOx;

    Sammanfattning : A long term challenge for society is to develop sustainable energy systems to reduce the dependence on fossil fuels and to decrease air pollution. This requires new alternatives regarding the supply of energy and increased efficiency of the future energy systems. Fuel cell technology is one such possible alternative. LÄS MER

  4. 23. Effects of trace elements in biodiesel on the performance of diesel oxidation catalysts in heavy-duty vehicles

    Författare :Jonas Granestrand; Lars Pettersson; Todd J. Toops; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Diesel Oxidation catalyst; heavy-duty vehicles; catalyst deactivation; biodiesel; NAP-XPS; XANES; Phosphorus; alkali metals; Pt Pd Al2O3; Chemical Engineering; Kemiteknik;

    Sammanfattning : To reduce net greenhouse gas emissions, a shift towards adoption of biofuels is ongoing in the transport sector. Heavy-duty diesel vehicles are equipped with aftertreatment equipment, comprising of catalysts and filters, and how this equipment is affected by the use of biofuels is not yet fully understood. LÄS MER

  5. 24. ALPHA-LINOLENIC ACID Postprandial Lipid Metabolism and Enzymatic Interesterification of Triacylgylcerols

    Författare :Julia Svensson; Bioteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; alpha-linolenic acid; triacylglycerol; postprandial lipemia; Lipozyme TL IM; interesterification;

    Sammanfattning : An important indicator of the metabolic capacity of humans is the ability to regulate plasma triacylglycerol levels and to clear triacylglycerol-rich lipoproteins (TRLs) from the circulation after a meal. This is crucial since most of the day is spent in the postprandial state. LÄS MER

  7. 25. Expanding the Amino Acid Alphabet by Design : Enhanced and Controlled Catalytic Activity in Folded Polypeptide Catalysts

    Författare :N. Johan V. Lindgren; Lars Baltzer; Harri Lönnberg; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Chemistry; Kemi; Organic Chemistry; organisk kemi;

    Sammanfattning : This thesis addresses structure and reactivity of polypeptide catalysts in reactions that mimic the hydrolysis of RNA and DNA. A designed helix-loop-helix motif was used as a scaffold where the amino acid residues were systematically varied. LÄS MER