Sökning: "primary nucleation"

Visar resultat 6 - 10 av 45 avhandlingar innehållade orden primary nucleation.

1. 6. Defect Formation during Solidification in Grey Iron Castings

   Författare :Lennart Elmquist; Ingvar Svensson; Attila Diószegi; Doru Stefanescu; Jönköping University; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Shrinkage Porosity; Grey Iron; Solidification; Nucleation; Primary Austenite; DAAS; Eutectic Cells; Microstructure; Macrostructure; Hot Spot; Oxygen; Hydrogen; Materials science; Teknisk materialvetenskap;

   Sammanfattning : The presence of defects is of major concern in the production of grey iron castings. Some defects are merely an aesthetic problem while others can be detrimental for the performance of the component. Among the several possible defects, shrinkage porosity is one of the more challenging to understand and avoid. LÄS MER

3. 7. 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

4. 8. The role of primary austenite morphology in cast iron

   Författare :Juan Carlos Hernando; Attila Diószegi; Arne Dahle; Jessica Elfsberg; Roberto Boeri; Jönköping University; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Solidification; Cast Iron; Primary Austenite; Microstructure Evolution; Coarsening; LGI; CGI; SGI; UTS; stelning; gjutjärn; primär austenit; mikrostrukturbildning; förgrovning; LGI; CGI; SGI; UTS;

   Sammanfattning : Automotive industry products portfolio includes a wide variety of complex-shaped cast iron products, such as truck engine components. Urged by strict environmental regulations on emissions, these components constantly need to combine higher demands on performance with lighter designs. LÄS MER

5. 9. 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

7. 10. Mechanisms for the Influence from Ice Nucleus Aerosols on Clouds and their Indirect Effects: Cloud Modelling

   Författare :Deepak Waman; MERGE: ModElling the Regional and Global Earth system; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; clouds; Radiation; Ice Nuclei; Primary Biological Aerosol Particles; Ice particles; Secondary ice; primary ice; Aerosol particles; thunderstorm;

   Sammanfattning : The role of multiple groups of primary biological aerosol particles (PBAPs) as ice nucleating particles (INPs), and of ice formation processes such as time-dependent freezing of various INPs, and various secondary ice production(SIP) mechanisms in overall ice concentration has been evaluated in a range of cloud systems by simulating them numerically with the state-of-the-art ‘Aerosol-Cloud’ (AC) model in a 3D mesoscale domain. Also, the mechanismsof aerosol indirect effects (AIEs) arising from anthropogenic INPs, and the responses to these AIEs from time-dependent INP freezing and SIP processes are investigated in the simulated clouds. LÄS MER