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Visar resultat 1 - 5 av 226 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Carboligation using the aldol reaction : A comparison of stereoselectivity and methods

    Författare :Derar Al-Smadi; Mikael Widersten; Ulf Nilsson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aldol reaction; cinchonine; FSA enzyme; homologation reactions; phenylacetaldehyde derivatives; samarium diiodide.;

    Sammanfattning : The research summarized in this thesis focuses on synthesizing aldehyde and aldol compounds as substrates and products for the enzyme D-fructose-6-aldolase (FSA). Aldolases are important enzymes for the formation of carbon-carbon bonds in nature. LÄS MER

  2. 2. Preliminary Design Investigations for the Selection of Optimum Reaction Degree for 1st Stage of a High Pressure Gas Turbine

    Författare :Hina Noor; Torsten Fransson; Konstantinos G. Kyprianidis; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 1D design; aerodynamic design parameters; flow kinematic; thermodynamics; rotor inlet temperature; cooled turbine; reaction degree; flow coefficient; stage loading;

    Sammanfattning : One-dimensional (1D) turbine design calculation phase requires a handful of input data and choice of design parameters to provide the blade flow path geometry along with the flow kinematics and thermodynamics properties at the blade mid-span. The choice of important aerodynamics design parameters namely reaction degree, nozzle guide vane NGV exit flow angle or flow coefficient and stage loading defines the mid-span flow velocity triangles. LÄS MER

  3. 3. Experiences of Miscarriage

    Författare :Caroline Jansson; Anneli Stavreus-Evers; Ingela Rådestad; Uppsala universitet; []
    Nyckelord :Miscarriage; spontaneous abortion; missed abortion; pregnancy loss; gender; measurement; emotion; care; stress; Medicinsk vetenskap; Medical Science;

    Sammanfattning : Experiences are unique and both men and women experience grief, anxiety, depressive symptoms after a miscarriage.The overall aim was to describe and measure experiences among women and men after a miscarriage. LÄS MER

  4. 4. 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

  5. 5. Thiol−ene Coupling of Renewable Monomers : at the forefront of bio-based polymeric materials

    Författare :Mauro Claudino; Mats K. G. Johansson; Mats Jonsson; Anna Wistrand; Sven Göthe; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Thiol-ene chemistry; monounsaturated fatty-acids; renewable resources; cis trans-isomerization; photopolymerization; networks; polyesters; thermal viscoelastic properties; thin-films; unsaturated macro lactones; coatings;

    Sammanfattning : Plant derived oils bear intrinsic double-bond functionality that can be utilized directly for the thiol–ene reaction. Although terminal unsaturations are far more reactive than internal ones, studies on the reversible addition of thiyl radicals to 1,2-disubstituted alkenes show that this is an important reaction. LÄS MER