Search for dissertations about: "oxygen isotope"

Showing result 1 - 5 of 46 swedish dissertations containing the words oxygen isotope.

  1. 1. Holocene climate and atmospheric circulation changes in northern Fennoscandia Interpretations from lacustrine oxygen isotope records

    University dissertation from Stockholm : Department of Physical Geography and Quaternary Geology, Stockholm University

    Author : Christina E. Jonsson; Stockholms universitet.; [2009]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; oxygen isotope; diatom silica; lake sediment; atmospheric circulation; North Atlantic Oscillation; northern Fennoscandia; The Holocene; Little Ice Age; NATURAL SCIENCES Earth sciences Exogenous earth sciences Physical geography; NATURVETENSKAP Geovetenskap Exogen geovetenskap Naturgeografi; Physical Geography; naturgeografi;

    Abstract : This thesis investigates how variations in the oxygen isotopic composition of lake waters in northern Fennoscandia are recorded in lake sediment archives, especially diatoms, and how these variations can be used to infer past changes in climate and atmospheric circulation. Results from analyses of the oxygen isotopic composition of lake water samples (δ18Olakew) collected between 2001 and 2006 show that δ18O of northern Fennoscandian lakes is mainly controlled by the isotopic composition of the precipitation (δ18Op). READ MORE

  2. 2. Nitrogen Cycling at Cold Climate Mine Sites in Northen Sweden

    University dissertation from Luleå : Luleå tekniska universitet

    Author : Lino Nilsson; Luleå tekniska universitet.; [2016]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nitrogen; Mining; Cycling; nutrients; Isotopes; Nitrogen-model; modelling; numerical-modelling; Isotope-tracing; Tracing; Isotope; geochemistry; Applied Geology; Tillämpad geologi;

    Abstract : High nitrogen discharge from mining sites has been an environmental issue that has been closely studied in the recent years. The environmental effects of high nitrogen discharge are mainly eutrophication, but can also lead to changed species composition and algae blooms. READ MORE

  3. 3. The origin of streamwater traced by oxygen-18

    University dissertation from Knivsta : Uppsala University

    Author : Allan Rodhe; Uppsala universitet.; [1987]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; streamflow generation; oxygen-18; isotope hydrograph separation; fractionation; Hydrology; Hydrologi;

    Abstract : .... READ MORE

  4. 4. Modified oxygen and hydrogen transport in Zr-based oxides

    University dissertation from Stockholm : KTH

    Author : Clara Anghel; KTH.; [2006]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Zirconia; Zirconium; Zircaloy; hydrogen and oxygen diffusion; SPP; oxygen dissociating elements; oxidation; dissociation; hydration; CO adsorption; molecular transport; porosity.; TECHNOLOGY Materials science; TEKNIKVETENSKAP Teknisk materialvetenskap;

    Abstract : Most metals and alloys in the presence of oxygen and moisture will instantaneously react and form a thin (2-5 nm) surface oxide layer. For further reaction to occur, oxygen ions and/or metal cations often diffuse through the already formed oxide layer. READ MORE

  5. 5. Deuterium isotope effects and the mechanism for a two-proton transfer from nitrogen to oxygen and oxygen to oxygen : rates and equilibria studied by microcalorimetry

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Kjell-Åke Engdahl; Uppsala universitet.; [1982]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; NATURVETENSKAP;

    Abstract : .... READ MORE