Sökning: "ICP-MS"
Visar resultat 21 - 25 av 62 avhandlingar innehållade ordet ICP-MS.
21. Isotopic analyses of biological materials by single and multi-collector sector field ICP-MS
Sammanfattning : Investigations concerning naturally occurring, mass dependent isotope fractionation of transition elements in biological materials have only been carried out during a very short period of time. Due to the lack of detailed descriptions of the analytical performance in previously reported work, the major focus of this study has therefore been to evaluate aspects of sample preparation and detection for obtaining precise and accurate isotopic ratios by multi-collector inductively coupled plasma mass spectrometry (MC- ICP-MS) using high mass-resolution. LÄS MER
22. Interconnections : Glass beads and trade in southern and eastern Africa and the Indian Ocean - 7th to 16th centuries AD
Sammanfattning : Glass beads comprise the most frequently found evidence of trade between southern Africa and the greater Indian Oceanbetween the 7th and 16th centuries AD. In this thesis beads recovered from southern African archaeological sites are organized into series, based on morphology and chemical composition determined by LA-ICP-MS analysis. LÄS MER
23. Mercury species transformations in marine and biological systems studied by isotope dilution mass spectrometry and stable isotope tracers
Sammanfattning : This thesis focuses on the implementation of species-specific isotope dilution (SSID) methodology and stable isotope tracers to determine mercury species occurrence and transformation processes in-situ and during sample treatment. Isotope enriched tracers of methyl-, ethyl- and inorganic mercury were synthesised and applied in different combinations to marine and biological samples. LÄS MER
24. Chloride Induced Corrosion of Reinforcement Steel in Concrete - Threshold Values and Ion Distributions at the Concrete-Steel Interface
Sammanfattning : The chloride threshold value (Cth), or critical chloride content, is defined as the chloride concentration at the depth of the reinforcement, which initiates the depassivation of steel in concrete. However, very limited information is available regarding the chloride distributions at the interface with the steel. LÄS MER
25. Crystallization and Differentiation Processes in the Thin Layered Alkali Gabbroic Intrusions of the Ulvö Gabbro Complex, Central Sweden
Sammanfattning : Fractional crystallization of magma is a commonly invoked mechanism for chemical differentiation in systems that range from volcanoes to entire planets. However, the processes that control separation of crystals and liquids in natural systems remain controversial, since the dynamics of crystallizing magma chambers cannot be studied directly. LÄS MER
