Search for dissertations about: "14C"

Showing result 1 - 5 of 121 swedish dissertations containing the word 14C.

  2. 1. Testing palaeomagnetic and 14C based geochronological methods in the Baltic Sea

    Author : Bryan Lougheed; Kvartärgeologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; coastal; geochronology; palaeomagnetic secular variation; PSV; radiocarbon; 14C; reservoir age; R t ; ΔR; salinity; δ18O; geomagnetic field; Holocene; deglacial; Fennoscandia.;

    Abstract : The Baltic Sea is a continental shelf sea that is influenced by both river runoff and marine water. The two water masses are vertically stratified in the Baltic Sea, resulting in a positive, estuarine circulation system, which has undergone changes in the past due to isostatic uplift of the Baltic basin. READ MORE

  4. 2. Biokinetics and radiation dosimetry of 14C-labelled triolein, urea, glycocholic acid and xylose in man. Studies related to nuclear medicine “breath tests” using accelerator mass spectrometry

    Author : Mikael Gunnarsson; Malmö Medicinsk strålningsfysik; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Clinical physics; radiology; tomography; medical instrumentation; Klinisk fysiologi; radiologi; tomografi; medicinsk instrumentering; Kärnfysik; Nuclear physics; xylose.; glycocholic acid; urea; triolein; Dosimetry; Biokinetic; AMS; Accelerator mass spectrometry; 14C; Breath test;

    Abstract : 14C-labelled substances have been used in biomedical research and clinical medicine for over 50 years. Physicians and scientists however, often hesitate to use these substances in patients and volunteers because the radiation dosimetry is unclear. READ MORE

  5. 3. Solar Activity Changes at the End of the Last Ice Age - Influences on Climate and Applications for Dating

    Author : Florian Adolphi; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Solar Activity; 10Be; 14C; radiocarbon calibration; time scale; geochronology; paleoclimate; ice cores; tree rings; IntCal; cosmogenic radionuclides;

    Abstract : Throughout its history Earth experienced a variety of natural climate changes. By investigating their spatial and temporal evolution we can increase the understanding of the mechanisms and dynamics underlying natural climate change and improve our general comprehension of the climate system. READ MORE

  6. 4. Investigations of temporal changes in climate and the geomagnetic field via high-resolution radiocarbon dating

    Author : Anette Mellström; Kvartärgeologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; wiggle-matching; Radiocarbon dating; 14C; 2800 cal BP; climate change; solar activity; palaeomagnetism; lake sediments; varves; post-depositional remanent magnetisation; PDRM; lock-in; peat deposits; Sweden;

    Abstract : Geological archives have shown periods of abrupt climate change in the relatively stable Holocene epoch (last ca. 11 700 years). One of these periods was around 2800 cal BP. Several records, mainly from Europe, reveal a shift towards wetter, cooler and windier conditions. READ MORE

  7. 5. Wild plants can improve their rhizosphere chemistry in acid soils

    Author : Marion Schöttelndreier; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Växtekologi; Plant ecology; wild plants.; time pattern; soil heterogeneity; rhizotrons; rhizosphere; pH; oxalic acid; nutrient availability; malic acid; hydroponics; citric acid; 14C; biodegradation; acid soils; aluminium toxicity; Soil Science; agricultural hydrology; Lantbrukshydrologi; marklära; Plant biochemistry; Växtbiokemi;

    Abstract : Growth conditions on acid soils may be hampered by low nutrient availability and phytotoxic Al (aluminium) concentrations. In this thesis I present my studies on adaptation mechanisms of wild plants to acid soils in the close root environment, the rhizosphere. READ MORE