Sökning: "stable Si isotopes"

Hittade 5 avhandlingar innehållade orden stable Si isotopes.

  1. 1. Fractionation of the stable silicon isotopes : analytical method developments and selected applications in geochemistry

    Författare :Emma Engström; Luleå tekniska universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Applied Geology; Tillämpad geologi;

    Sammanfattning : During the last few decades, variations in the 'natural' isotopic abundances of stable elements (termed 'fractionation') have received considerable interest from the scientific community. Though analytical methods and techniques for the measurement of isotopic abundances with adequate figures of merit have been available for light elements (e.g. LÄS MER

  2. 2. Diatom-rich sediment formation in lakes

    Författare :Petra Zahajská; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Silicon; silica; diatom; biogenic silica; lake; sediment; stable Si isotopes; Ge Si; Yellowstone; Northern Sweden;

    Sammanfattning : Unicellular photosynthetic golden algae called diatoms are one of the most abundant silicifying organisms. Diatoms take up silicon and build their frustules, in the form of biogenic silica (BSi), which have high preservation potential, and thus are found in sediments. LÄS MER

  3. 3. Isotope-based reconstruction of the biogeochemical Si cycle : Implications for climate change and human perturbation

    Författare :Xiaole Sun; Carl-Magnus Mörth; Christoph Humborg; Per Andersson; Brian Fry; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; diatoms; biogenic silica BSi ; dissolved Si DSi ; Si isotope fractionation; the Baltic Sea; geokemi; Geochemistry;

    Sammanfattning : The global silicon (Si) cycle is of fundamental importance for the global carbon cycle. Diatom growth in the oceans is a major sequestration pathway for carbon on a global scale (often referred to as the biological pump). LÄS MER

  4. 4. Fractionation of the stable silicon isotopes studied using MC-ICP-MS : analytical method developments and applications in geochemistry

    Författare :Emma Engström; Luleå tekniska universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Applied Geology; Tillämpad geologi;

    Sammanfattning : In spite of the high Si abundance in natural systems, expected significant mass-dependent fractionations, and the importance of the element in many areas of the Earth sciences (focusing on e.g. LÄS MER

  5. 5. Integrating fluvial processes into the global Si cycle

    Författare :Patrick Frings; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Silicon (Si) is ubiqutious in natural waters as dissolved silica (DSi) and is used as a nutrient by many plant and animal species. DSi ultimately derives from the weathering of silicate minerals, a process which also consumes atmospheric CO2 and couples the silicon and carbon cycles. LÄS MER