Sökning: "ultraviolet radiation"

Visar resultat 11 - 15 av 130 avhandlingar innehållade orden ultraviolet radiation.

  1. 11. Ultraviolet radiation, vitamin A and the skin : photodynamic studies on natural and synthetic retinoids

    Författare :Berit Berne; Uppsala universitet; []
    Nyckelord :MEDICINE; MEDICIN;

    Sammanfattning : .... LÄS MER

  3. 12. Effects of solar radiation on the abiotic and bacterially mediated carbon flux in aquatic ecosystems

    Författare :Alexandre Magno Anesio; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; bacteria; dissolved inorganic carbon DIC ; bioavailability; aquatic macrophytes; photooxidation; detritus decomposition; Ultraviolet radiation; dissolved organic carbon DOC ; fungi; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

    Sammanfattning : In this Thesis, I studied some of the current aspects of organic matter photochemistry. I analyzed abiotic phototransformations of several types of dissolved (DOM) and particulate organic matter (POM). I also evaluated the effects of phototransformation of several types of DOM on bacteria. LÄS MER

  4. 13. Evolutionary ecology of ultraviolet-B radiation stress tolerance in amphibians

    Författare :Maarit Pahkala; Trevor Beebee; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; amphibians; anomalies; embryonic development; geographic variation; growth; Rana arvalis; Rana temporaria; survival; UV-B radiation; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; populationsbiologi; Population Biology;

    Sammanfattning : During the last decades many amphibian species and populations have experienced declines and extinctions in different parts of the world. Anthropogenic activities are believed to account for these declines, and one of the hypothesized causes has been the increased level of ultraviolet-B (UV-B) radiation due to depletion of the stratospheric ozone layer. LÄS MER

  5. 14. On the ecophysiology of Baltic cyanobacteria focusing on bottom-up factors

    Författare :Malin Mohlin; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Allelopathy; Aphanizomenon sp.; Baltic Sea; Cyanobacteria; Diazotrophic; Multi-factorial; Nitrogen; Nodularin; photosynthetic active radiation; Phosphorus; ultraviolet radiation; UV-A; UV-B;

    Sammanfattning : Cyanobacterial blooms in the Baltic Sea are dominated by diazotrophic cyanobacteria, i.e. Aphanizomenon sp. and Nodularia spumigena. LÄS MER

  7. 15. Optical Studies For Synchrotron Radiation Beamlines

    Författare :Walan Grizolli; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Synchrotron Radiation; Optics; X-ray Optics; Beamline; Polarimetry; Coherence; Storage Rings; Diffraction Limited Storage Rings;

    Sammanfattning : Synchrotron radiation sources have greatly contributed to the progress in many fields of science. The development of the storage ring technologies has made possible to obtain very low emittance electron beams, which together with the use of undulators allow guiding a very high photon flux into a very small spot required by the experiments. LÄS MER