Sökning: "Tenax TA"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden Tenax TA.

  1. 1. Oxidation of terpenes in indoor environments : A study of influencing factors

    Författare :Linda Pommer; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; Monoterpene; Ozone O3 ; Nitrogen dioxide NO2 ; Nitrogen oxide NO ; Relative humidity RH ; Modelling; Scrubber; Experimental design; Interaction; Volatile organic compounds VOC ; Sick buildings syndrome SBS ; Principal component analysis PCA ; Indoor air; Ventilation; Tenax TA; Sodium sulphite; Miljökemi; Environmental chemistry; Miljökemi; analytisk kemi; Analytical Chemistry;

    Sammanfattning : In this thesis the oxidation of monoterpenes by O3 and NO2 and factors that influenced the oxidation were studied. In the environment both ozone (O3) and nitrogen dioxide (NO2) are present as oxidising gases, which causes sampling artefacts when using Tenax TA as an adsorbent to sample organic compounds in the air. LÄS MER

  3. 2. Off-gassing from thermally treated lignocellulosic biomass

    Författare :Eleonora Borén; Markus Broström; Sylvia H. Larsson; Peter Björklund; Lorenz Gerber; Henrik Antti; Capucine Dupont; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Torrefaction; steam explosion; enclosed storage; CO; CO2; O2 depletion; VOCs; Tenax-TA; SPME; process settings; storage temperature; storage time;

    Sammanfattning : Off-gassing of hazardous compounds is, together with self-heating and dust explosions, the main safety hazards within large-scale biomass storage and handling. Formation of CO, CO2, and VOCs with concurrent O2 depletion can occur to hazardous levels in enclosed stored forest products. LÄS MER

  4. 3. Volatile metabolites from microorganisms in indoor environments : sampling, analysis and identification

    Författare :Anna-Lena Sunesson; Alvin Fox; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Adsorbents; Analysis; Cultivation; Determination; Gas chromatography; Identification; Indicator substances; Indoor air; Mass spectrometry; Metabolites; Microbial volatile organic compounds; Optimization; Sampling; Sick buildings; Thermal desorption; Aspergillus versicolor; Cladosporium cladosporioides; Paecilomyces variotii; Pénicillium commune; Phialophora fastigiata; Streptomyces albidoflavus;

    Sammanfattning : Microorganisms are able to produce a wide variety of volatile organic compounds. This thesis deals with sampling, analysis and identification of such compounds, produced by microorganisms commonly found in buildings. LÄS MER

  5. 4. 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

  7. 5. Determination of benzene in urine and breath for monitoring of benzene exposure

    Författare :Göran Ljungkvist; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Biological monitoring; benzene; breath; urine; dynamic headspace; membrane; gas chromatography; mass spectrometry; thermal desorption;

    Sammanfattning : The aim of this work was to develop and validate methods for determination of unmetabolized benzene in breath and urine. The methods were intended for the bio monitoring of benzene to assess both occupational and environmental exposure.A method was developed for the determination of benzene in end-exhaled air. LÄS MER