Sökning: "SFE"

Visar resultat 1 - 5 av 23 avhandlingar innehållade ordet SFE.

  1. 1. Development of Methods for Determination of Fat and Trace Constituents in Food, with Emphasis on Supercritical Fluid Extraction

    Författare :Hans Berg; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Supercritical fluid extraction; Steroids; SFE; Sample preparation; Meat; Lipid classes; Food; Fatty acid composition; Fat content; 3-butanediol; 2; Diacetyl; Acetoin; Androstenone; vitamins A and E.; Analytical chemistry; Analytisk kemi;

    Sammanfattning : Sample preparation is the most time-consuming step in an analysis. Traditional sample preparation techniques consume large amounts of organic solvents, are time-consuming and are difficult to automate. LÄS MER

  3. 2. Determination of Persistent Organic Pollutants in Solid Environmental Samples Using Accelerated Solvent Extraction and Supercritical Fluid Extraction. Exhaustive extraction and sorption/desorption studies of PCBs

    Författare :Erland Björklund; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sorption; Sediment; PCBs; Polychlorinated Biphenyls; POP; Persistent Organic Pollutants; SFE; Supercritical Fluid Extraction; Accelerated Solvent Extraction; ASE; Desorption; Analytical chemistry; Analytisk kemi;

    Sammanfattning : Human activity is constantly causing environmental problems due to production and release of numerous chemicals. A group of compounds of special concern is persistent organic pollutants (POP). These toxic, lipophilic chemicals have a high chemical and biological stability, and tend to accumulate in the lipid phase of living organisms. LÄS MER

  4. 3. Extraction of PCBs from Sediments: Towards Bioavailability Assessment Based on Supercritical Fluid Extraction

    Författare :Tobias Nilsson; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Analytisk kemi; Analytical chemistry; Bioavailability; PCB; SFE;

    Sammanfattning : Persistent organic pollutants (POPs) pose serious threats to our global environment. These compounds have high chemical and biological stability and they are also very lipophilic. LÄS MER

  5. 4. Analytical Supercritical Fluid Extraction of Lipid Containing Samples

    Författare :Mattias Järemo; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; SFC; extraction cell; liquid samples; fat retainers; lipids; SFE; carbon dioxide; Analytical chemistry; Analytisk kemi;

    Sammanfattning : Traditionally, sample work-up has been associated with different kinds of liquid extraction techniques involving a large consumption of hazardous solvents. There are today regulations that aims at replacement of dangerous chemicals which has created a need for new extraction techniques. LÄS MER

  7. 5. 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