Sökning: "N-DIMETHYLACETAMIDE"

Hittade 3 avhandlingar innehållade ordet N-DIMETHYLACETAMIDE.

  1. 1. Cellulose degradation in pulp fibers studied as changes in molar mass distributions

    Författare :Rickard Berggren; KTH; []
    Nyckelord :cellulose; kraft pulp; birch; spruce; ozonation; acid hydrolysis; degradation; MMD; size-exclusion chromatography; light scattering; molar mass; chain scission;

    Sammanfattning : In this thesis, size-exclusion chromatography (SEC) of woodpolymers dissolved in lithium chloride/N,N-dimethylacetamide(LiCl/DMAc) has been used to characterize the molar massdistributions (MMD) of wood polymers in pulp fibers afterchemical degradation.Characterization of birch kraft pulps subjected to ozonedegradation and acid hydrolysis, respectively, rendereddifferent changes in the MMD. LÄS MER

  3. 2. Synthesis of indolocarbazoles, bisindoles and related sulfur containing systems

    Författare :Tomasz Janosik; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :Alkaloids; bisindoles; dithiins; indoles; indolocarbazoles; metallation; pentathiepins; polysulfides; tetrathiocins; thionation; X-ray crystallography.;

    Sammanfattning : This thesis is focussed mainly on the synthesis and reactions of various indolocarbazoles, bisindoles and related sulfur containing systems, all possessing structural features present in many biologically active, natural or synthetic compounds. In the first part, synthetic routes towards the planar, pentacyclic ring systems of indolo[2,3-c]earbazole and indolo[3,2-a]carbazole are described. LÄS MER

  4. 3. Characterisation of kraft pulps by size-exclusion chromatography and kraft lignin samples by capillary zone electrophoresis

    Författare :Elisabeth Sjöholm; KTH; []
    Nyckelord :;

    Sammanfattning : In the present thesis two analytical methods forcharacterisation of underivatised pulp and lignin samplesobtained from kraft pulping of hardwood and softwood areevaluated. The first method is the use of lithiumchloride/N,N-dimethylacetamide (LiCl/DMAc) for dissolution andsize-exclusion chromatography (SEC) of pulps. LÄS MER