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Visar resultat 1 - 5 av 14 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Crystallization of Parabens : Thermodynamics, Nucleation and Processing

    Författare :Yang Huaiyu; Åke Rasmuson; Joop ter Horst; KTH; []
    Nyckelord :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 ;

    Sammanfattning : 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. LÄS MER

  2. 2. Structural, Kinetic and Thermodynamic Aspects of the Crystal Polymorphism of Substituted Monocyclic Aromatic Compounds

    Författare :Michael Svärd; Åke Rasmuson; Hugo Meekes; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polymorphism; crystallization; thermodynamics; kinetics; nucleation; crystallography; solubility; phase equilibria; polymorphic transformation; solution history; metastable zone; classical theory of nucleation; two-step theory of nucleation; cluster; crystal structure prediction; lattice energy; molecular mechanics; force field; electrostatic potential; potential energy hypersurface; m-aminobenzoic acid; m-hydroxybenzoic acid; Chemical engineering; Kemiteknik;

    Sammanfattning : This work concerns the interrelationship between thermodynamic, kinetic and structural aspects of crystal polymorphism. It is both experimental and theoretical, and limited with respect to compounds to substituted monocyclic aromatics. LÄS MER

  3. 3. Investigation and Prediction of Small Intestinal Precipitation of Poorly Soluble Drugs : a Study Involving in silico, in vitro and in vivo Assessment

    Författare :Sara Carlert; Hans Lennernäs; Bertil Abrahamsson; Patrick Augustijns; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; gastrointestinal precipitation; crystallization; crystal nucleation; crystal growth; classical nucleation theory; poorly soluble drugs; drug absorption; biopharmaceutics classification system; in vitro in vivo correlations IVIVC ; in silico prediction; human intestinal fluid; dog intestinal fluid; simulated intestinal fluid; Biofarmaci; Biopharmaceutics;

    Sammanfattning : The main objectives of the present project were to increase the understanding of small intestinal precipitation of poorly soluble pharmaceutical drugs, investigate occurrence of crystalline small intestinal precipitation and effects of precipitation on absorption. The aim was to create and evaluate methods of predicting crystalline small intestinal drug precipitation using in vivo, in vitro and in silico models. LÄS MER

  4. 4. Crystallization in additive manufacturing of metallic glass

    Författare :Anders Ericsson; Hållfasthetslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Amorphous metals; Crystallization; Laser powder bed fusion; Neutron scattering; Phase-field theory; Classical nucleation theory;

    Sammanfattning : Metallic glasses are non-crystalline metals that are obtained by rapid cooling of the melt to bypass crystallization. The amorphous atomic structure shows enhanced properties relative to the crystalline counterpart. For example, enhanced mechanical properties, improved corrosion resistance, as well as excellent soft magnetic properties. LÄS MER

  5. 5. Investigations intothe crystallization of butyl paraben

    Författare :Huaiyu Yang; Åke Rasmuson; Mårten Behm; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Butyl paraben; Solubility; Thermodynamic; Activity; Activity coefficient; Second order correlation; Liquid-liquid phase separation; Ternary phase diagram; Nucleation; Induction time; Free energy; Interfacial energy; Nuclei critical radius Cooling crystallization; Evaporation crystallization; Chemical engineering; Kemiteknik;

    Sammanfattning : In thisproject, solubility of butyl paraben in 7 puresolvents and 5 ethanol aqueous solvents has been determined at from 1 ℃to 50 ℃. Thermodynamic properties of butyl paraben have been measured by DifferentialScanning Calorimetey. LÄS MER