Sökning: "activity coefficients"

Visar resultat 1 - 5 av 53 avhandlingar innehållade orden activity coefficients.

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

3. 2. Model for activity coefficients and solubilities of Na2CO3 and Na2SO4 in high-temperature solutions

   Författare :Marta Anna Bialik; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; scaling; Pitzer model; activity coefficient; solubility; sodium carbonate; sodium sulfate; boiling point raise; double salt; solid solution; burkeite;

   Sammanfattning : Scaling of sodium sulfate and sodium carbonate double salts has long been recognized as a problem in the black liquor evaporation process. These salts are abundant in black liquor and often tend to precipitate on heat transfer areas, thereby significantly decreasing the heat transfer efficiency. LÄS MER

4. 3. 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

5. 4. Investigation of vanadium-containing oxide systems : CALPHAD and experiments

   Författare :Yang Yang; Malin Selleby; Caisa Samuelsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Calphad; thermodynamic modelling; compound energy formalism; evaporation kinetics; activation energy; TGA; activity;

   Sammanfattning : Fundamental studies on thermodynamic properties of vanadium-containing oxides systems are essential to understand practical vanadium metallurgical process. The CALPHAD technique is here applied to the thermodynamic modelling of the V-O, Ca-V-O and Ti-V-O systems. The compound energy formalism is used for all the solution phases. LÄS MER

7. 5. Origin of solar surface activity and sunspots

   Författare :SARAH JABBARI; AXEL BRANDENBURG; Vasilis Archontis; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Sun-Solar activity-Sunspots; teoretisk astrofysik; Theoretical Astrophysics;

   Sammanfattning : In the last few years, there has been significant progress in the development of a new model for explaining magnetic flux concentrations, by invoking the negative effective magnetic pressure instability (NEMPI) in a highly stratified turbulent plasma. According to this model, the suppression of the turbulent pressure by a large-scale magnetic field leads to a negative contribution of turbulence to the effective magnetic pressure (the sum of non-turbulent and turbulent contributions). LÄS MER