Found 10483 publications. Showing page 263 of 420:
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Environmental information systems on the Internet: A need for change. IFIP Advances in Information and Communication Technology, 359
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Chemical speciation of fine airborne particles in Abu Dhabi. NILU OR
Chemical speciation results of PM2.5 filter samples from eight sites in Abu Dhabi are discussed. This is the third interim report, covering a total of 40 filter samples. As one aim of this sampling study was to use the speciation results for health impact studies, samples with high particle loads and high degree of blackness were selected for analysis, and compared to samples with typical particle loads. Particles with diameters less than 2.5 µm were analysed for elements, inorganic ions and carbonaceous fractions.
The most abundant elements were found to be crustal elements, contributing on average 14% to PM2.5 mass. Reconstructing the mass of crustal oxides, approximately 44% of the fine particle mass was estimated to be associated with mineral dust. The concentrations of most heavy metals were below limit values for annual averages at all sites. For nickel, it was found that the Guideline Value may be exceeded at one traffic site.
Inorganic ions (sulphate, nitrate, ammonium, sodium, chloride) explain on average 34% of the PM2.5 mass in Abu Dhabi. Remarkably high sulphate concentrations account for the major part (on average 26%). Particulate sulphate in Abu Dhabi is likely to have both natural (as a result of the local composition of mineral dust) and anthropogenic sources which cannot be separated with the applied analytical methods. An anthropogenic contribution of ~6% comes from the secondary inorganic ions nitrate and ammonium.
Total carbon, which consists of elemental carbon, organic carbon and carbonate carbon contributed on average 14% to PM2.5 mass. About 30% of total carbon was estimated to be carbonate of likely natural origin. Elemental carbon and most organic carbon are expected to be of anthropogenic origin.
PM in Abu Dhabi has a strong signature of natural sources (mineral dust). A detailed apportionment of sources requires further analyses.
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Monitoring of greenhouse gases and aerosols at Svalbard and Birkenes: Annual report 2009. NILU OR
The report summaries the activities and results of the greenhouse gas monitoring at the Zeppelin and observatory situated on Svalbard in Arctic Norway during the period 2001-2009 and the greenhouse gas monitoring and aerosol observations from Birkenes for 2009.
The monitoring programme is performed by the NILU - Norwegian Institute for Air Research and funded by the Norwegian Pollution Control Authority (SFT) (now Climate and Pollution Agency) and NILU - Norwegian Institute for Air Research.
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