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Visar resultat 1 - 5 av 20 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Recovery of Rare Earth Elements from an Apatite Concentrate

   Författare :Mahmood Alemrajabi; Kerstin Forsberg; Åke C. Rasmuson; Koen Binnemans; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rare earth elements; precipitation; nitrophosphate process; hollow fiber supported liquid membrane extraction; Chemical Engineering; Kemiteknik;

   Sammanfattning : Rare earth elements (REE) are a group of 17 elements including lanthanides, yttrium and scandium; which are found in a variety of classes of minerals worldwide. The criticality of the application, lack of high grade and economically feasible REE resources and a monopolistic supply situation has raised significant attention in recovery of these metals from low grade ores and waste materials. LÄS MER

3. 2. Identification and Variation of some Functionality Related Characteristics of Pharmaceutically Relevant Solid Materials and their Effect on Product Performance

   Författare :Frauke Fichtner; Göran Alderborn; Åke Rasmuson; Peter Kleinebudde; Uppsala universitet; []
   Nyckelord :Pharmaceutics; Particle size distribution; Degree of agglomeration; Amorphous lactose; Matrix agglomerates; Drug release; Compactability; Tablet tensile strength; Particle fracture strength; Surfactant; Compression; Galenisk farmaci;

   Sammanfattning : The aim of this thesis was to identify some functionality related characteristics of pharmaceutically relevant solid materials and to study the effect of their variation on processing behaviour and product performance. For this purpose, particles with different characteristics were prepared under a variety of conditions by crystal agglomeration, wet granulation and spray drying. LÄS MER

4. 3. Crystallization of Metal Fluoride Hydrates from Mixed Acid Solutions

   Författare :Kerstin Forsberg; Åke Rasmuson; Alison Lewis; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; crystallization; crystal growth; b-FeF3.3H2O; iron fluoride trihydrate; CrF3.3H2O; pickling; pickle bath; hydrofluoric acid; nitric acid; stainless steel; Chemical engineering; Kemiteknik;

   Sammanfattning : In this work crystal growth and nucleation of b-FeF3×3H2O and crystallization of chromium (III), iron (III) and nickel (II) fluoride hydrates from mixed acid (1-3 mol/kg HNO3 and 1-6 mol/kg free HF) have been investigated. The solubility of b-FeF3×3H2O has been determined in solutions of different hydrofluoric acid (1-7mol/ kg) and nitric acid (0-7mol/ kg) concentrations at 30, 40 and 50°C. LÄS MER

5. 4. Solubility and polymorphism of molecular compounds

   Författare :Sandra Gracin; Åke C. Rasmuson; David J. W. Grant; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical engineering; solubility; prediction of solubility; UNIFAC; activity coefficients; activity of the solid phase; polymorphism; controlled crystallization; sonication.; Kemiteknik; Chemical engineering; Kemiteknik;

   Sammanfattning : This thesis deals with the controlled crystallization of small organic molecules and is focused on solubility and polymorphism. The solubility was determined for phenylacetic acid, p-hydroxyphenylacetic acid, p-aminophenylacetic acid, p-hydroxybenzoic acid and ibuprofen in both water and in a range of organic solvents. LÄS MER

7. 5. 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