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Visar resultat 21 - 25 av 1318 avhandlingar som matchar ovanstående sökkriterier.

  1. 21. Aerosol–cloud interactions in a warming Arctic

    Författare :Linn Karlsson; Paul Zieger; Radovan Krejci; Annica M. L. Ekman; Birgit Wehner; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; aerosols; clouds; aerosol-cloud interactions; Arctic; climate; field studies; Environmental Sciences; miljövetenskap;

    Sammanfattning : Atmospheric aerosol particles are small liquid or solid particles suspended in the air. They are present in the atmosphere all around us and affect the planetary energy balance by scattering and absorbing radiation and by interacting with clouds. In model projections of future climate, aerosol–cloud interactions contribute a lot of uncertainty. LÄS MER

  2. 22. Bioaerosols and their importance for low-level Arctic clouds

    Författare :Gabriel Pereira Freitas; Paul Zieger; Radovan Krejci; Kevin J. Noone; Claudia Mohr; Martin Gallagher; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Bioaerosols; Aerosols; Clouds; Arctic; Cloud Condensation Nuclei; Ice Nucleating Particles; Sea Spray Aerosol; Environmental Sciences; miljövetenskap;

    Sammanfattning : Bioaerosols are microorganisms or functional parts of them or other biological matter suspended in air. Examples are bacteria, viruses, pollen, spores, or smaller plant debris. In the atmosphere, bioaerosols can play various functional roles, such as facilitating the spread of genetic material. LÄS MER

  3. 23. Solar radiation effects on decomposition and decomposers of plant litter in lakes

    Författare :Måns Denward; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; glucosidase; photo inhibition; photo oxidation; littoral; lakes; ergosterol; fungi; phragmites; bacteria; UV-B; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

    Sammanfattning : This thesis summarizes the results of a series of experiments, from test tube up to field study scale, performed to increase the understanding of solar radiation effects on decomposition and microbial decomposers of plant litter in stagnant water of littoral zones. In conclusion, I suggest that fungi play a significant role in the decomposition of plant litter submersed in lakes, and that their distribution is dependent on detritus quality and water chemistry, but also tends to be inversely related to the occurrence of bacteria attached to the litter. LÄS MER

  4. 24. Simulation and analysis of radiation from runaway electrons

    Författare :Mathias Hoppe; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; tokamak; runaway electrons; synthetic diagnostics; fusion; synchrotron radiation; plasma physics; bremsstrahlung;

    Sammanfattning : Electron runaway constitutes one of the primary threats to future tokamak fusion reactors such as ITER. Successful prevention and mitigation of runaways relies on the development of theoretical models which accurately describe the dynamics of runaway electrons, and these models must in turn be validated in experiments. LÄS MER

  5. 25. Small science on big machines: Politics and practices of synchrotron radiation laboratories

    Författare :Olof Hallonsten; Research Policy Institute (RPI); []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; big science; little science; sophistication; collectivization; European Synchrotron Radiation Facility; Stanford Synchrotron Radiation Lightsource; MAX-lab; scientific entrepreneurs; changing dynamics of science; Synchrotron radiation; research policy; science policy;

    Sammanfattning : Synchrotron radiation laboratories are large scientific facilities where various scientific experiments are carried out by the use of radiation produced by particle accelerators. Research with synchrotron radiation emerged in the 1960s and 1970s as a peripheral activity at particle physics laboratories. LÄS MER