Sökning: "natural sources"

Visar resultat 26 - 30 av 1616 avhandlingar innehållade orden natural sources.

  1. 26. Polybrominated diphenylethers in the environment - Local and long range transport

    Författare :Arnout ter Schure; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Substance Flow Analysis; Spatial Variation; Sources; PCB; PBDE; Latitude; Global Fractionation; Frogs; Deposition; Atmosphere; Baltic Sea; Ekologi; Temperature; Washout ratio; Ecology;

    Sammanfattning : I have studied the sources, long range transport, and rates of flow of polybrominated diphenyl ethers (PBDEs), from the technosphere to the Baltic ecosystems. PBDEs are mainly used in polymers, which are applied in electrical equipment to prevent overheating or flashover and are produced in large quantities. LÄS MER

  3. 27. On the lifecycle of aerosol particles : Sources and dispersion over Scandinavia

    Författare :Peter Tunved; Hans-Christen Hansson; Johan Ström; Douglas Nilsson; Urs Baltensperger; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aerosols; Meteorology; Meteorologi;

    Sammanfattning : Aerosol particles are likely important contributors to our future climate. Further, during recent years, effects on human health arising from emissions of particulate material have gained increasing attention. LÄS MER

  4. 28. Quantification of sources and removal mechanisms of atmospheric aerosol particles

    Författare :Henrik Grythe; Johan Ström; Dominick Spracklen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aerosol; aerosol removal; aerosol emission; aerosol sources; FLEXPART; Arctic aerosol; Applied Environmental Science; tillämpad miljövetenskap;

    Sammanfattning : The focus of this work has been to quantify important processes for climatically relevant aerosols, and to improve our understanding of, and ability to accurately model, aerosols in the atmosphere on a large scale. This thesis contains five papers focused on different parts of the life cycle of atmospheric aerosol particles. LÄS MER

  5. 29. The neurotoxin β-N-methylamino-L-alanine (BMAA) : Sources, bioaccumulation and extraction procedures

    Författare :Sandra Ferreira Lage; Sara Rydberg; Ulla Rasmussen; Hanna Mazur-Marzec; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plant Physiology; växtfysiologi;

    Sammanfattning : β-methylamino-L-alanine (BMAA) is a neurotoxin linked to neurodegeneration, which is manifested in the devastating human diseases amyotrophic lateral sclerosis, Alzheimer’s and Parkinson’s disease. This neurotoxin is known to be produced by almost all tested species within the cyanobacterial phylum including free living as well as the symbiotic strains. LÄS MER

  7. 30. Removal processes in sewage treatment plants : Sludge quality and treatment efficiency of structurally diverse organic compounds

    Författare :Ulrika Olofsson; Peter Haglund; Staffan Lundstedt; Juliane Hollender; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Environmetrics; flame retardants; GCxGC; non-targeted screening; mass flow; metals; plasticizers; poorly removed contaminants; POP; PPCP; prediction; Principal Component Analysis; removal efficiency; sewage; sewage treatment plants; sludge; sludge adsorption; sources; time-trend analysis; Environmental chemistry; Miljökemi;

    Sammanfattning : Large and ever-increasing numbers of chemicals, including large quantities of a broad spectrum of organic compounds are used in modern society. More than 30 000 of the more than 100 000 chemical substances registered in the EU are estimated to be daily used, of which many will be discharged into the waste-streams handled by municipal sewage treatment plants (STPs). LÄS MER