Search for dissertations about: "solvent activity"

Showing result 1 - 5 of 101 swedish dissertations containing the words solvent activity.

  2. 1. Microcalorimetric methods for direct measurement of solubility and solvent activity

    Author : Dennis Berling; Biokemi och Strukturbiologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; enthalpy of solution; solubility; solvent fugacity; solvent activity; Isothermal calorimetry; vapour pressure; Chemistry; Kemi;

    Abstract : New calorimetric methods for direct measurement of solubility and solvent activity are presented. The classical role of calorimetry for measurements of enthalpic parameters is abandoned and the technique is instead used for assessing thermodynamic quantities related to the chemical potential of a substance in a solution. READ MORE

  4. 2. Crystallization of Parabens : Thermodynamics, Nucleation and Processing

    Author : Yang Huaiyu; Åke Rasmuson; Joop ter Horst; KTH; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Nucleation; Induction time; Interfacial energy; Ethyl paraben; Propyl paraben; Butyl paraben; Methanol; Ethanol; Propanol; Acetone; Ethyl acetate; Solubility; Thermodynamics; Activity; Activity coefficient; Liquid-liquid phase separation; Ternary phase diagram; Melting point; Boiling point; Polarity; Cooling crystallization; Sandwich crystal; Porous; Particle Vision and Measurement; Focused Beam Reflectance Method; Infrared Spectroscopy; Confocal Raman Microscopy; X-Ray Diffraction; Differential Scanning Calorimetry; SRA - E-Science SeRC ; SRA - E-vetenskap SeRC ;

    Abstract : In this work, the solubility of butyl paraben in 7 pure solvents and in 5 different ethanol-water mixtures has been determined from 1 ˚C to 50 ˚C. The solubility of ethyl paraben and propyl paraben in various solvents has been determined at 10 ˚C. READ MORE

  5. 3. Creating Optical Activity: Total Spontaneous Resolution and Viedma Ripening

    Author : Per Martin Björemark; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Optical activity; absolute asymmetric synthesis; total spontaneous resolution; Viedma ripening; grinding; chirality; conglomerate; coordination compound; coordination polymer; single crystal X-ray diffraction; solvent free oxidation; nantioselective sulfide oxidation; solid state VCD;

    Abstract : The creation of optical activity has been considered as something impossible even though reports of such creation via total spontaneous resolution since the 1940´s have been published. More recently Viedma ripening have been developed that also produce enantiopure bulk product. Both methods are examples of absolute asymmetric synthesis i.e. READ MORE

  6. 4. The influence of temperature on enzyme selectivity in organic media

    Author : Åsa Jönsson; Bioteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; water activity; sub-zero temperatures; enantioselectivity; peptide yields; asymmetric reductions of ketones; peptide synthesis; ADH from Thermoanaerobium brockii; subtilisin; Enzyme catalysis; a-chymotrypsin; organic solvent; aqueous media; Biotechnology; Bioteknik;

    Abstract : The influence of different reaction parameters on enzyme selectivity was investigated. The reaction conditions studied were solvent dependence, water activity and reaction temperature. READ MORE

  7. 5. Towards molecular weight-dependent uses of kraft lignin

    Author : Ayumu Tagami; Mikael Lindström; Olena Sevastyanova; Anna Wistrand; Stefan Backa; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; kraft lignin; successive solvent fractionation; molecular weight; structural analysis; thermal stability; heat capacity; antioxidant activity; methylene blue sorption; tunicate cellulose nanofiber-starch lignin composites films; film properties; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Abstract : There is growing demand for a more efficient use of polymers that originate from renewable feedstocks due to the depleting supply of fossil fuels, based on economic and environmental reasons. As a result, lignin has attracted renewed interest as a resource for various bioproducts. READ MORE