Sökning: "Solvent collection"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden Solvent collection.

  1. 1. Determination of Fat-Soluble Vitamins in Foods Based on Supercritical Fluid Extraction

    Författare :Charlotta Turner; Kemiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Supercritical fluid extraction; Solvent collection; Solid phase trapping; SFE; Selectivity; Retinol; Milk powder; Lipase; Food; Enzymatic hydrolysis; Alcoholysis; Candida antarctica; Tocopherol; Vitamins; Analytical chemistry; Analytisk kemi;

    Sammanfattning : Sample clean-up methodologies based on supercritical fluid extraction (SFE) have been developed for determination of fat-soluble vitamins in foods. This thesis focuses on method development, stressing important issues concerning sample pre-treatment, extraction conditions and collection parameters. LÄS MER

  3. 2. Extending relativistic linear response theory to address solvent effects

    Författare :Joel Creutzberg; Beräkningskemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Response theory; Polarizable embedding; Complex Polarization Propagator; Relativistic effects;

    Sammanfattning : The central aim of this thesis is to derive, implement and test new methods to calculate various types of spectroscopies of compounds containing heavy elements in an aqueous environment. Methods that can target such systems have to consider the following:(i) It is crucial to take relativistic effects into account. LÄS MER

  4. 3. Improved Techniques for Protein Analysis Focusing on Membrane Proteins and Hydrophobic Peptides

    Författare :Theres Redeby; Åsa Emmer; Jonas ergquist; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Integral membrane proteins; Hydrophobic peptides; Sample handling; MALDI-TOF-MS; Structured sample support; CE; fraction collection; microchannel; Analytical chemistry; Analytisk kemi;

    Sammanfattning : In this thesis, the vital cell functions performed by integral membrane proteins (IMPs) are briefly discussed. Such proteins are under-represented in most protein studies due to the hydrophobic nature of IMPs, which seriously complicate their solubilization, sample handling, preparation, separation and analysis. LÄS MER

  5. 4. Superhydrophobic coatings of wax and polymers sprayed from supercritical solutions

    Författare :Louise Ovaskainen; Lars Wågberg; Charlotta Turner; Eric Beckman; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; superhydrophobic coatings; polymer; wax; supercritical carbon dioxde; RESS; Chemical Engineering; Kemiteknik;

    Sammanfattning : The possibility of using supercritical carbon dioxide (scCO2) as the primary solvent in a spray process for producing superhydrophobic surfaces have been examined in this work. Using scCO2 as solvent will have considerably lower environmental impact compared to an organic solvent since scCO2 is considered a green solvent as it is non-toxic, non-flammable and recyclable. LÄS MER

  7. 5. Isocyanates and Amines – Sampling and Analytical Procedures

    Författare :Åsa Marand; Gunnar Skarping; Marianne Dalene; Daniel Karlsson; Roy Rando; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Isocyanates; Amines; Polyurethane; Air sampling; Industrial hygiene; Mass spectrometry; Liquid chromatography; Chemiluminescence; Analytical chemistry; Analytisk kemi;

    Sammanfattning : This thesis covers sampling and analytical procedures for isocyanates (R-NCO) and amines (R-NH2), two kinds of chemicals frequently used in association with the polymeric material polyurethane (PUR). Exposure to isocyanates may result in respiratory disorders and dermal sensitisation, and they are one of the main causes of occupational asthma. LÄS MER