Sökning: "chemical composition"

Visar resultat 1 - 5 av 1311 avhandlingar innehållade orden chemical composition.

  1. 1. Direct conversion of methane-to-methanol: transition-metal dimer sites in small-pore zeolites: First-principles calculations and microkinetic modeling

    Författare :Unni Engedahl; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; partial methane oxidation; microkinetic modeling; SSZ-13; CHA; alloy; transition metals; zeolites; density functional theory;

    Sammanfattning : Direct conversion of methane to methanol is a highly desired reaction. Partially oxidizing methane into a liquid fuel at ambient temperature and pressure would enable utilization of natural gas and biogas to a much larger extent than what is possible today. LÄS MER

  3. 2. Computational Studies of Chemical Interactions: Molecules, Surfaces and Copper Corrosion

    Författare :Joakim Halldin Stenlid; Tore Brinck; Thomas Bligaard; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; computational chemistry; density functional theory; chemical interactions; reactivity descriptors; copper corrosion; surface and materials science; nucleophilic substitution reactions; heterogeneous catalysis; transition metal oxides; nanotechnology; beräkningskemi; täthetsfunktionalteori; kemiska interaktioner; reaktivitetsdeskriptorer; kopparkorrosion; yt- och materialvetenskap; nukleofila substitutionsreaktioner; heterogen katalys; överångsmetalloxider; nanoteknologi; Kemi; Chemistry;

    Sammanfattning : The chemical bond – a corner stone in science and a prerequisite for life – is the focus of this thesis. Fundamental and applied aspects of chemical bonding are covered including the development of new computational methods for the characterization and rationalization of chemical interactions. LÄS MER

  4. 3. Influence of total pressure on complete oxidation of methane over Pd/Al2O3 catalysts

    Författare :Carl-Robert Florén; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pd Al2O3; methane oxidation; multiscale flow-reactor model; total pressure;

    Sammanfattning : Natural gas and biogas, which have methane as their main component, are interesting choices of fuel to reduce the anthropogenic emissions of greenhouse gases. However, as methane is a greenhouse gas, uncombusted methane should be removed from the combustion gases. Emission control catalysts can preferably be used to completely oxidise methane. LÄS MER

  5. 4. Titanium oxide nanoparticle production using high power pulsed plasmas

    Författare :Rickard Gunnarsson; Ulf Helmersson; Grzegorz Greczynski; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis covers fundamental aspects of process control when growing titanium oxide nanoparticles in a reactive sputtering process. It covers the influence of oxygen containing gas on the oxidation state of the cathode from which the growth material is ejected, as well as its influence on the particles oxidation state and their nucleation. LÄS MER

  7. 5. Study of bio-oil and bio-char production from thermal and catalytic hydrotreatment of simulated pyrolysis oil under mild conditions

    Författare :Elham Nejadmoghadam; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Stabilization; soluble solid; alumina-supported catalyst; insoluble solid char; simulated pyrolysis oil; catalytic hydrotreatment;

    Sammanfattning : Pyrolysis oil derived from fast pyrolysis of lignocellulosic biomass is a promising alternative energy source used to produce renewable biofuels. However, the high reactivity of unsaturated oxygenated compounds in pyrolysis oil results in charring and deactivation of the catalyst under severe hydrotreatment conditions. LÄS MER