Search for dissertations about: "polymorph"

Showing result 1 - 5 of 21 swedish dissertations containing the word polymorph.

  2. 1. Polymorphism and Crystallization of p-Aminobenzoic Acid

    Author : Sandra Gracin; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; controlled crystallization; polymorphism; p-aminobenzoic acid;

    Abstract : Polymorphs are solid phases where the chemical composition isequal but the crystal structure differs. Many organic compoundsmay appear in more than one crystalline structure. READ MORE

  4. 2. Investigating polymorphism in small molecules using three-dimensional electron diffraction

    Author : Molly Lightowler; Xiaodong Zou; Hosea M. Nelson; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; 3D electron diffraction; structure determination; polymorphism; crystallisation; phase identification; small molecule; oorganisk kemi; Inorganic Chemistry;

    Abstract : For scientific, regulatory and intellectual property reasons, the discovery and characterisation of polymorphic systems is an integral aspect of the development process of any solid-formulated drug product. Yet, these studies are often hindered by crystal quality and size, poor yields and the generation of mixtures of phases. READ MORE

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

    Author : Michael Svärd; Åke Rasmuson; Hugo Meekes; KTH; []
    Keywords : 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;

    Abstract : 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. READ MORE

  6. 4. Physical properties and crystallization of theophylline co-crystals

    Author : Shuo Zhang; Åke Rasmuson; Per Svensson; Mårten Behm; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Theophylline; oxalic acid; glutaric acid; maleic acid; co-crystal; decomposition temperature; melting temperature; solubility; crystallization; Molecular transport processes in chemical process engineering; Molekylära transportprocesser i kemisk processteknik;

    Abstract : This work focuses on the physical properties and crystallization of theophyline co-crystals. Co-crystals of theophylline with oxalic acid, glutaric acid and maleic acid have been investigated. The DSC curves of these co-crystals show that their first endothermic peaks are all lower than the melting temperature of theophylline. READ MORE

  7. 5. Development of syntheses for nanostructured titania and silica

    Author : Gunnar Örn Simonarson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lithium intercalation; nanoparticles; X-ray characterization; mesoporous silica; mesoporous titania; spray deposition; Titanium dioxide;

    Abstract : Nanostructured titania is of great interest for a variety of energy and environmental applications, including conversion of solar energy, for energy storage systems and removal of organic pollutants in water and air. Titania is composed of earth abundant elements, it is environmentally friendly and chemically stable which makes it an attractive material to utilize. READ MORE