Sökning: "Methane"

Visar resultat 1 - 5 av 297 avhandlingar innehållade ordet Methane.

  1. 1. Abiotic and biotic methane dynamics in relation to the origin of life

    Detta är en avhandling från Stockholm : Department of Geological Sciences, Stockholm University

    Författare :Nguyen Thanh Duc; Stockholms universitet.; [2012]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; methane; methanogens; methane formation; methane oxidation; lake sediment; olivine; origin of life; Geochemistry; geokemi;

    Sammanfattning : Methane (CH4) plays an important role in regulating Earth’s climate. Its atmospheric concentrations are related to both biotic and abiotic processes. The biotic one can be formed either by chemoautotrophic or heterotrophic pathways by methanogens. LÄS MER

  2. 2. Catalytic combustion of methane

    Detta är en avhandling från Stockholm : Kemiteknik

    Författare :Philippe Thevenin; KTH.; [2002]
    Nyckelord :catalytic combustion; gas turbine; methane; palladium; alumina; barium; lanthanum; oxidation; preparation; temperature-programmed oxidation TPO ; decomposition; reoxidation; X-ray photoelectron spectroscopy XPS ; metal-support interaction; deactiva;

    Sammanfattning : Catalytic combustion is an environmentally benign technologywhich has recently reached the stage of commercialization.Palladium is the catalyst of choice when considering gasturbines fuelled with natural gas because of its superioractivity for methane oxidation. LÄS MER

  3. 3. Bimetallic palladium catalysts for catalytic combustion of methane

    Detta är en avhandling från Stockholm : Kemiteknik

    Författare :Katarina Persson; KTH.; [2004]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical engineering; catalytic combustion; gas turbine; methane; palladium; bimetal; morphology; TPO; TEM; EDS; methane activity; stability; pressure; Kemiteknik; TECHNOLOGY Chemical engineering; TEKNIKVETENSKAP Kemiteknik;

    Sammanfattning : Catalytic combustion is a promising combustion technique in gas turbines, which results in ultra low levels of NOx, CO and unburned hydrocarbons. Due to the low combustion temperature achieved in catalytic combustion almost no thermal NOx is formed. The focus in this thesis will be on the first stage in a catalytic combustion chamber, i.e. LÄS MER

  4. 4. Lake Fluxes of Methane and Carbon Dioxide

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Eva Podgrajsek; Uppsala universitet.; [2015]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; air-lake gas exchange; carbon dioxide; eddy covariance; floating chambers; methane; waterside convection; Meteorologi; Meteorology;

    Sammanfattning : Methane (CH4) and carbon dioxide (CO2) are two important greenhouse gases. Recent studies have shown that lakes, although they cover a small area of the globe, can be very important natural sources of atmospheric CH4 and CO2. LÄS MER

  5. 5. Emission of methane from northern lakes and ponds

    Detta är en avhandling från Stockholm : Institutionen för geologiska vetenskaper

    Författare :Martin Wik; Stockholms universitet.; [2016]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lakes; ponds; water bodies; methane; fluxes; ebullition; stable isotopes; arctic; subarctic; carbon cycling; climate change; geokemi; Geochemistry;

    Sammanfattning : Northern lakes and ponds are abundant and emit large amounts of the potent climate forcer methane to the atmosphere at rates prone to change with amplified Arctic warming. In spite of being important, fluxes from surface waters are not well understood. LÄS MER