Sökning: "Hans-erik Högberg"

Hittade 4 avhandlingar innehållade orden Hans-erik Högberg.

  1. 1. Purification, Stereoisomeric Analysis and Quantification of Biologically Active Compounds in Extracts from Pine Sawflies, African Butterflies and Orchid Bees

    Författare :Joakim Bång; Erik Hedenström; Kristina Sjödin; Hans-Erik Högberg; Anna-Karin Borg-Karlsson; Mittuniversitetet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Semiochemicals; sex pheromone; pine sawflies; Bicyclus; Euglossa; chiral separation; derivatisation; GC-­MS; Organic chemistry; Organisk kemi;

    Sammanfattning : Stereochemistry plays an important role in nature because biologically important molecules such as amino acids, nucleotides and sugars, only exist in enantiomerically pure forms. Semiochemicals carry messages, between the same species (pheromones) and between different species (allelochemicals). LÄS MER

  2. 2. Deracemization of Functionalized Alcohols via Combined Ruthenium and Enzyme Catalysis

    Författare :Ann-Britt L. Fransson; Jan-Erling Bäckvall; Hans-Erik Högberg; Stockholms universitet; []

    Sammanfattning : The major part of this thesis describes the synthesis of enantiopure alcohols and diols by combining ruthenium-catalyzed racemization or epimerization and lipase-catalyzed asymmetric transformations. A minor part of this thesis is focused on ruthenium-catalyzed redox reactions for transfer hydrogenation of 1,3-cycloalkanediketones. LÄS MER

  3. 3. Enzymes as catalysts in synthesis of enantiomerically pure building blocks : secondary alcohols bearing two vicinal stereocenters

    Författare :Rong Liu; Hans-Erik Högberg; Torbjörn Norin; Thorleif Anthonsen; KTH; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; enzyme; kinetic resolution; enantioselectivity; lipase; diastereoselectivity; epimerisation; metal-catalysed transformation; intramolecular alkylation.; Chemistry; Kemi;

    Sammanfattning : Enzymes as tools in organic synthesis have provided enormous advantages. This thesis deals with the applications of enzymes in the kinetic resolutions of racemic compounds. The stereochemistry of chiral compounds and the kinetics of α/β hydrolase lipases are presented. LÄS MER

  4. 4. Fourier Transform Infrared Spectroscopy in Industrial Hygiene Applications : Assessment of Emissions from and Exposures in Wood Processing Industries

    Författare :Urban Svedberg; Christer Edling; Bo Galle; Hans-Erik Högberg; Nils Plato; Uppsala universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Medicine; FTIR; Exposure; Emission; Saw mills; Wood pellets; Tracer gas; Monoterpenes; Hexanal; Carbon monoxide; Open path FTIR; Medicin; Dermatology and venerology; clinical genetics; internal medicine; Dermatologi och venerologi; klinisk genetik; invärtesmedicin;

    Sammanfattning : This thesis evaluates the use of Fourier Transform Infrared Spectroscopy (FTIR) as an approach to the increasingly difficult air sampling challenges within the field of occupational and environmental hygiene. The application of FTIR is exemplified by the assessment of emissions from and exposures in the sawmill and pellet industries. LÄS MER