Sökning: "Heterogeneous reactions"

Visar resultat 16 - 20 av 146 avhandlingar innehållade orden Heterogeneous reactions.

  1. 16. Development of catalytic enantioselective C-C bond-forming and cascade transformations by merging homogeneous or heterogeneous transition metal catalysis with asymmetric aminocatalysis

    Författare :Samson Afewerki; Armando Córdova; MICHELANGELO GRUTTADAURIA; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; transition metals; aldehydes; heterogeneous catalysis; amino acid; organocatalysis; α-allylation; β-alkylation; dynamic transformations; polysubstituted; carbocycles; spirocyclic oxindoles; all-carbon quaternary stereocenters;

    Sammanfattning : Chiral molecules play a central role in our daily life and in nature, for instance the different enantiomers or diastereomers of a chiral molecule may show completely different biological activity. For this reason, it is a vital goal for synthetic chemists to design selective and efficient methodologies that allow the synthesis of the desired enantiomer. LÄS MER

  3. 17. Photochemical reactions of lignin: Opportunities for valorisation

    Författare :Alexander Michael Riddell; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biomass; NMR; Lignin; Photolysis; Photochemistry; Kraft;

    Sammanfattning : Lignin is the second most abundant biopolymer after cellulose and is the largest bio-based source of aromatic compounds. However, its heterogeneous and recalcitrant structure makes it difficult to depolymerise for use in renewable chemicals production. LÄS MER

  4. 18. Reduction of the N2O Emission from Fluidized Bed Combustion by Afterburning

    Författare :Lennart Gustavsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; chemical modelling; fuel injection; nitrous oxide; fluidized bed combustion; fluidized beds; afterburning; homogeneous heterogeneous reactions; N2O reduction; fluidized bed boiler; N2O emissions;

    Sammanfattning : A method for reducing N2O emissions from fluidized bed combustion is presented and investigated. In contrast to flame combustion, fluidized bed combustion generates significant amounts of nitrous oxide (N2O) which are emitted to the atmosphere. LÄS MER

  5. 19. Iron-Catalyzed Reactions and X-Ray Absorption Spectroscopic Studies of Palladium- and Ruthenium-Catalyzed Reactions

    Författare :Arnar Guðmundsson; Jan-Erling Bäckvall; Hans-Joachim Knölker; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Iron; XAS; Cycloisomerization; DKR; Oxidation; organisk kemi; Organic Chemistry;

    Sammanfattning : The focus of this thesis is twofold: The first is on the application of iron catalysis for organic transformations. The second is on the use of in situ X-ray absorption spectroscopy (XAS) to investigate the mechanisms of a heterogeneous palladium-catalyzed reaction and a homogeneous ruthenium-catalyzed reaction. LÄS MER

  7. 20. Nitrous Oxide Emission from Circulating Fluidized Bed Combustion

    Författare :Lars-Erik Åmand; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; air supply dependence; fluidized beds; homogeneous heterogeneous reactions; fluidized-bed boilers; bed temperature dependence; N2O emissions; circulating fluidized-bed boilers; gas-concentration profiles;

    Sammanfattning : In the present thesis N2O results are presented from several measurement projects on two commercial circulating fluidized bed (CFB) boilers. Traditional parameter studies have been carried out, as well as test programs where various nitrogen-containing species were injected into the furnace or gas-concentration profiles in the combustion chamber were measured. LÄS MER