Sökning: "ice nucleation"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden ice nucleation.

1. 1. Water Condensation and Freezing in the Atmosphere: Exploring Deliquescence and Ice Nucleation

   Författare :Dimitri Castarède; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hygroscopicity; Deliquescence; Atmosphere; Particles; Ice Nucleation; Ice Nucleation Chamber;

   Sammanfattning : Atmospheric aerosols play key roles in numerous atmospheric processes. They affect human health, are substrates and components for atmospheric chemistry, and via their contribution to clouds affect the water cycle and the energy balance of the planet. LÄS MER

3. 2. 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

4. 3. Molecular investigations of atmospherically relevant interface processes: ice formation and water accommodation on ice and organic surfaces

   Författare :Xiangrui Kong; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; atmosphere; kinetics; Environmental molecular beam; ice nucleation; supersaturation; accommodation coefficient; phase transition; alcohols; green chemistry;

   Sammanfattning : Clouds and aerosols play important roles in the climate system by affecting on atmospheric chemistry, the radiation budget of the atmosphere, and the water cycle including the formation of precipitation. Climate models with predictive power require quantitative descriptions of aerosols and clouds, but several key processes remain to be fully understood. LÄS MER

5. 4. X-ray scattering and spectroscopy of supercooled water and ice

   Författare :Jonas A. Sellberg; Anders Nilsson; Lars G. M. Pettersson; Thomas Loerting; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supercooled water; ice; x-ray scattering; x-ray spectroscopy; free-electron laser; kemisk fysik; Chemical Physics;

   Sammanfattning : This thesis presents experimental studies of water and ice at near-atmospheric pressures using intense x-rays only accessible at synchrotrons and free-electron lasers. In particular, it focuses on the deeply supercooled, metastable state and its implications on ice nucleation. LÄS MER

7. 5. Toward Anti-icing and De-icing Surfaces : Effects of Surface Topography and Temperature

   Författare :Golrokh Heydari; Per Claesson; Eric Tyrode; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; anti-icing; topography; supercooled water; wetting hysteresis; superhydrophobic; contact angle; nucleation; freezing delay; de-icing; ice adhesion; hydration water; liquid-like layer; smooth; lubrication; anti-is; topografi; underkylt vatten; vätningshysteres; superhydrofob; kontaktvinkel; kärnbildning; avisning; isadhesion; hydrerat vatten; vätskeliknande skikt; smörjning; Kemi; Chemistry;

   Sammanfattning : Icing severely affects society, especially in the Nordic countries. Iceaccumulation can result in critical performance problems and safetyconcerns for instance in road, air and sea transportation, transmissionlines, marine and offshore structures, wind turbines and heat exchangers. LÄS MER