Sökning: "polysulfides"

Hittade 5 avhandlingar innehållade ordet polysulfides.

  1. 1. Some factors affecting the amount of residual phase lignin during kraft pulping

    Författare :Mikael E. Lindström; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Deligniflcation; Residual phase lignin; Hydrogensulfide ion; Hydroxide ion; Polysulfides; Ionic strength; Temperature; Lignin; Kraftpulping; Selectivity; viscosity; Kappa number; chemical degradation; Disproportionation; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : The amount of lignin which needs to be removed according to the slow residual delignification phase in kraft pulping, i e residual phase lignin, has been studied as a function of the process conditions. The variebles studied were the concentrations of hydroxide ions, hydrogensulfide ions, sodium ions (ionic strength) and temperature. LÄS MER

  3. 2. Electrochemical generation of polysulfide liquor and sodium hydroxide from white liquor

    Författare :Mårten Behm; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; White liquor; Kraft pulping; Polysulfides; Sodium hydroxide; Electrolysis; Autocatalysis; Cation-selective membranes; DSA; Nickel; Graphite; Electrochemistry; Elektrokemi;

    Sammanfattning : .... LÄS MER

  4. 3. 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

  5. 4. In-situ Investigations of Lithium-Sulfur Batteries

    Författare :Matthew Sadd; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : As the demand for high energy-density storage devices increases, we must look beyond the current state of the art technology, the lithium-ion battery. Lithium-ion battery technologies are approaching their theoretical limit in terms of capacity, and now that the demand for longer-range electric vehicles (EVs) and the implementation of grid storage is increasing, we need to provide technologies that can go beyond what is currently possible. LÄS MER

  7. 5. Interfacing spectrophotometry to process liquors applications to kraft pulping

    Författare :Xiaotian Yang; KTH; []
    Nyckelord :Kraft cooking; On-line; Sulfide; Lignin; Polysulfide excess sulfur; Anthraquinone-2-sulfonate; Anthraquinone; Nafion membrane; UV-Vis; ATR-probe; Spectrophotometric;

    Sammanfattning : This thesis summarizes the outcome of work performed withthe objective to contribute to the knowledge and development ofthe kraft cooking process using spectrophotometricinterfaces.In kraft cooking, it is desirable to maximize the removal oflignin in the cook without loss of pulp strength. LÄS MER