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Visar resultat 1 - 5 av 33 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Titan’s ionosphere and dust : – as seen by a space weather station

   Författare :Oleg Shebanits; Jan-Erik Wahlund; Wolf Dietrich Geppert; Olle Björneholm; Erik Vigren; Cesar Bertucci; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Titan; Cassini; Ionosphere; Dusty plasma; Ion-ion plasma; Langmuir probe; aerosols; tholins; Space and Plasma Physics; Rymd- och plasmafysik;

   Sammanfattning : Titan, the largest moon of Saturn, is the only known moon with a fully developed nitrogen-rich atmosphere, its ionosphere is detectable as high as 2200 km above its surface and hosts complex organic chemistry. Titan’s atmosphere and ionosphere has striking similarities to current theories of these regions around Earth 3.5 billion years ago. LÄS MER

3. 2. The effect of spacecraft charging on low-energy ion measurements around comet 67P/Churyumov-Gerasimenko

   Författare :Sofia Bergman; Gabriella Stenberg Wieser; Martin Wieser; Gert Brodin; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Spacecraft charging; low-energy ions; space physics; plasma physics; comet; Rosetta; SPIS; rymd- och plasmafysik; Space and Plasma Physics;

   Sammanfattning : A spacecraft in space interacts with the surrounding environment and aqcuires an electrostatic potential. Charged particles are constantly bombarding the surface of the spacecraft, and at the same time solar EUV radiation induces photoemission, causing electrons to be emitted from the surface. LÄS MER

4. 3. Active insulation : possibilities of utilizing free charges in air

   Författare :Mats Sjöberg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; capacitively coupled discharge; charge accumulation; breakdown mechanism; dielectric covered structures; electric field homogenization; active insulation; dynamic charging; microdischarge; dielectric barrier discharge; dielectric breakdown strength; electric field reduction; space charge; air gaps; surface charge;

   Sammanfattning : .... LÄS MER

5. 4. Acceptor-doped barium zirconate: Oxidation, hydration and space-charge formation

   Författare :Anders Lindman; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; BaZrO3; space charge; point defects; oxidation; GW; hydration; density functional theory; grain boundaries; interatomic potential; perovskites;

   Sammanfattning : The current production and use of fossil fuels is not sustainable and new technologies are needed to become more independent of these fuels.The hydrogen economy, with the fuel cell as an efficient converter of chemical to electrical energy, is a desirable alternative.For this to become a reality, new materials with tailored properties are required. LÄS MER

7. 5. On the defective origin of conductive and structural properties of oxides: insights from first principles

   Författare :Anders Lindman; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; point defects; thermodynamic modeling; proton conductors; oxyhydrides; density-functional theory; BaZrO3; polarons; grain boundaries; space charges; oxides;

   Sammanfattning : Oxides are versatile materials with applications in many different research fields; especially those related to clean energy technologies, such as fuel cells, batteries and solar panels. Many functional properties of these materials derive from lattice imperfections, or defects, and a lot of effort has been put into fine tuning these materials by modifying their structure on the atomic scale. LÄS MER