Sökning: "isotope enriched tracers"

Hittade 3 avhandlingar innehållade orden isotope enriched tracers.

  1. 1. Mercury species transformations in marine and biological systems studied by isotope dilution mass spectrometry and stable isotope tracers

    Författare :Lars Lambertsson; Wolfgang Frech; John Munthe; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Analytical chemistry; Mercury; methylmercury; ethylmercury; Thimerosal; speciation; methylation; demethylation; brackish water sediment; natural waters; GC-ICP-MS; species-specific isotope dilution; isotope enriched tracers; Analytisk kemi; Analytical chemistry; Analytisk kemi; analytisk kemi; Analytical Chemistry;

    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

  3. 2. Instrumental and methodological developments for isotope dilution analysis of gaseous mercury species

    Författare :Tom Larsson; Erik Björn; Holger Hintelmann; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mercury; gas; species; speciation analysis; isotope dilution analysis; permeation tubes; Analytical chemistry; Analytisk kemi;

    Sammanfattning : This thesis deals with instrumental and methodological developments for speciation analysis of gaseous mercury (Hg(g)), based on isotope dilution analysis (IDA). The studied species include Hg0, (CH3)2Hg, CH3HgX and HgX2 (where X symbolises a negatively charged counter ion in the form of a halide or hydroxyl ion). LÄS MER

  4. 3. Determination of mercury chemical speciation in the presence of low molecular mass thiols and its importance for mercury methylation

    Författare :Van Liem-Nguyen; Erik Björn; Ulf Skyllberg; Cynthia Gilmour; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mercury; methylmercury; LMM thiol; mass spectrometry; biogeochemistry; soil; sediment; ICP; WinSGW; modeling; S XANES; ligand exchange; stability constant; boreal wetlands; analytisk kemi; Analytical Chemistry; Environmental Science; miljövetenskap;

    Sammanfattning : Methylmercury (MeHg) is a neurotoxic compound that threatens the well-being of humans and wildlife. It is formed through the methylation of inorganic mercury (HgII) under suboxic/anoxic conditions in soils, sediment and waters. LÄS MER