Search for dissertations about: "composition feedback"

Showing result 21 - 25 of 51 swedish dissertations containing the words composition feedback.

  2. 21. Studies of the Arctic Ocean sea ice cover and hydrothermal heat fluxes

    Author : Christian Stranne; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Oceanography; Arctic climate sensisitvity;

    Abstract : Since reliable ice extent estimates from satellite data became available in 1979 the Arctic sea ice cover has followed a declining long term trend. Over the last decade the decline has accelerated with record low sea ice extents recorded in 2002, 2005, 2007 and 2012. READ MORE

  4. 22. Numerical Simulations for Studies of Unsteady Combustion in Practical Combustion Devices

    Author : Sven-Inge Möller; Förbränningsfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; plasmas; fluiddynamik; Gaser; plasma; Thermal engineering; applied thermodynamics; termodynamik; Termisk teknik; fluid dynamics; Gases; Physics; Fysik; Fysicumarkivet A:2002:Möller;

    Abstract : A major problem in the design of combustion equipment is to prevent the occurrence of combustion instabilities. Combustion instabilities appear as periodic oscillations in pressure and heat release through a feedback mechanism between the fluid dynamics and the combustion process. These oscillations may induce e.g. READ MORE

  5. 23. Reconstruction of Holocene atmospheric mineral dust deposition from raised peat bogs in south–central Sweden

    Author : Jenny Sjöström; Malin Kylander; Jonatan Klaminder; Martina Hättestrand; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mineral dust; paleodust; peat; Sweden; Holocene; mineralogy; XRD;

    Abstract : Atmospheric mineral dust plays a dynamic role in the climate system acting both as a forcing and a feedback mechanism. To date, the majority of paleodust studies have been conducted on marine sediments or polar ice cores, while terrestrial deposition has been less studied. READ MORE

  6. 24. Soil Organic Matter Dynamics and Methane Fluxes at the Forest – Tundra Ecotone in Fennoscandia

    Author : Sofie Sjögersten; Gaius Shaver; Uppsala universitet; []
    Keywords : Decomposition; forest – tundra ecotone; environmental change; Fennoscandia; methane; soil organic matter; subarctic.; naturgeografi; Physical Geography;

    Abstract : This thesis presents results from several studies that have focused on the carbon and nutrient dynamics in soils at the forest – tundra ecotone in Fennoscandia. The main objectives of the study were: (i) to investigate the links between the physical environment, above-ground vegetation communities, soil carbon storage, nutrient status and the chemical composition of the soil organic matter (SOM), and (ii) to quantify trace gas fluxes (methane and carbon dioxide) between mesic soils and the atmosphere. READ MORE

  7. 25. Commensal microbes, immune reactivity and childhood inflammatory bowel disease

    Author : Cecilia Barkman; Göteborgs universitet; []
    Keywords : Inflammatory bowel disease; IBD; Pediatric; Childhood; Microbiota; T cells; B cells; cytokine; IL-12; monocytes; phagocytosis; intracellular signaling pathway; Crohn s disease; ulcerative colitis; children; flora;

    Abstract : Inflammatory bowel disease (IBD) is characterized by chronic and relapsing intestinal inflammation of unknown etiology, but immune activation by the commensal microbiota probably plays a major role. The two major categories of IBD are ulcerative colitis and Crohn’s disease. READ MORE