Sökning: "TFA"

Visar resultat 1 - 5 av 6 avhandlingar innehållade ordet TFA.

  1. 1. Ultra-short-chain perfluoroalkyl acids : Environmental occurrence, sources and distribution

    Författare :Maria Björnsdotter; Ingrid Ericson Jogsten; Anna Kärrman; Leo W. Y. Yeung; Tom Harner; Örebro universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PFASs; TFA; TFMS; point sources; precursors; solar radiation; atmospheric oxidation; atmospheric deposition; flux; Arctic;

    Sammanfattning : Ultra-short-chain perfluoroalkyl acids (PFAAs) is a group of highly fluorinated and very stable chemicals. Their small molecular structure in combination with the acidic functional group result in highly polar compounds and concern has been raised as these substances may threaten our drinking water supplies. LÄS MER

  3. 2. Haloacetates in precipitation

    Författare :Lena von Sydow; Linköpings universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; INTERDISCIPLINARY RESEARCH AREAS; TVÄRVETENSKAPLIGA FORSKNINGSOMRÅDEN;

    Sammanfattning : Haloacetates are a group of fluorinated, chlorinated and brominated organic compounds that pose a potential threat to the environment, because they are present in relatively high concentrations in precipitation and they are toxic to plants. At the time the research described in this thesis was begun, it had been suggested that atmospheric degradation of chlorinated solvents and CFC replacements were responsible for the presence of haloacetates in precipitation in populous regions. LÄS MER

  4. 3. Capillary electrophoresis methods for the separation of the basic compound lidocaine and its metabolites

    Författare :Magnus S. Andersson; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kemi; Chemistry;

    Sammanfattning : For the separation of the basic compound lidocaine and its metabolites a variety of capillary electrophoresis (CE) methods have been developed. This includes capillary zone electrophoresis (CZE), micellar electrokinetic chromatography (MEKC) and nonaqueous CE separations. The parameters affecting the separations were investigated and optimized. LÄS MER

  5. 4. Bisindoles : synthesis and reactions

    Författare :Eva Koch; KTH; []
    Nyckelord :;

    Sammanfattning : In this thesis, synthesis of various bisindoles have beendeveloped.2,3-Bis-(3-indolyl) succinic acid derivatives wereobtained via iodine promoted coupling of the trianion ofindole-3-acetic acid (IAA) or from the dianion of themethylester of IAA. These compounds were converted to2,3-bis(3-indolyl) maleimides (arcyriarubin analogues) by DDQoxidation. LÄS MER

  7. 5. Implementing spectrum commons: Implications for Thailand

    Författare :Nattawut Ard-Paru; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spectrum commons; institutional analysis and development IAD framework; spectrum assignment; spectrum allocation; Radio Regulations RR ; World Radiocommunication Conference WRC ; spectrum management;

    Sammanfattning : Spectrum is a natural and limited resource that needs to be managed both internationally and nationally because of the unique propagation characteristics of radio waves. Once transmitted, a radio signal propagates until its power is depleted. Furthermore, electromagnetic energy does not recognize borders between countries. LÄS MER