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Atmospheric hydrocarbons (HCs) have been determined during a winter and a spring sampling period at several urban and a semi-rural site in the Vienna region. HC relative concentration patterns were generally consistent, however large concentration differences were observed at the various sampling sites. Concentration ratios for ‘semi-rural’, ‘suburban’ and ‘city street level’ sites were 1:2.5:10 for the winter case. HC concentrations at a 52 m high building were around 40% of the values at street level for species emitted by traffic. The relative abundances of aromatics (47%), alkanes (37%) and alkenes (11%) in the vienna urban atmosphere compare well with results from Berlin, while in other cities under comparison (e.g. Washington, Sydney, and Leningrad) alkanes are the most abundant volatile HC class (45 to 69%). 相似文献
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Aerosol and snow samples were collected over a three weeks period in September 1996 and over two weeks in April and May 1997 at Mount Sonnblick Observatory (SBO) at 3106 m elevation. The samples were analyzed for lipid organic compounds. The main group found in the samples were phthalates, which seem to origin from a local emission. Furthermore, n- and branched alkanes, phenols, aliphatic alcohols, esters and aldehydes were identified. Total carbon measurements were performed for the aerosols in 1996 and the extraction yields are given. TOC analysis in 1997 was done for the snow phase. Scavenging ratios are calculated for the corresponding organic substances for both years. These are 10 to 100 times smaller than the ratio found for sulfate at the same site. The spring values are generally higher than the fall scavenging ratios. 相似文献
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Schwikowski M. Novo A. Baltensperger U. Delmas R. Gäggeler H. W. Kasper A. Kuhn M. Maupetit F. Nickus U. Preunkert S. Puxbaum H. Rossi G. C. Schöner W. Wagenbach D. 《Water, air, and soil pollution》1997,93(1-4):67-91
In order to investigate the seasonal and geographical distribution of snow concentrations anddeposition fluxes of environmentally relevant ionic species in the Alps, the international programSNOSP was initiated. In the framework of this program, intercomparisons of snow samplingtechniques and analytical methods to determine the ionic species C1-, NO 3 - ,SO 4 2- , K+, Na+, NH4 +, Mg2+, and Ca2+, as well as the pH and the specificconductivity were performed. The concentrations of these species in the snow samples collectedin the SNOSP program varied by orders of magnitude with, e.g., concentrations of NO 3 - , SO 4 2- , and NH4 + ranging from 0.2-60, 0.2-90, and 0.1-60 µeq L-1,respectively. The intercomparisons revealed a reasonable agreement of the determinations of thespecies Cl-, NO 3 - , SO 4 2- , Na+, and NH4 + in snow. Results were less satisfactory for K+, Mg2+, Ca2+,and H+, mainly due to the very low concentrations. In conclusion, recommendations areformulated for the reliable derivation of chemical inventories from snow packs. 相似文献
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Sree Usha Bauer Heidi Fuerhacker Maria Ellinger Reinhard Schmidt Heidrun Puxbaum Hans 《Water, air, and soil pollution》2000,124(1-2):177-186
Hydrocarbons emissions were measured from an aerationtank of a municipal wastewater treatment pilot plant. The collected off-gas samples werecharacterised for C2–C7 hydrocarbons usingGC-FID analytical technique while the total volatileorganic compounds (TVOC) were measured using acontinuous hydrocarbon gas analyser. Approximately,the estimated emission rates for 1 m3 of wastewaterfrom this aeration tank were 5 mgC of C2–C7hydrocarbons, and an average of 7 gC of TVOC. Withexception to toluene, all other measured hydrocarbonsare emitted less than 1 mgC day-1. The results supportthe view that a significant reduction in annualemissions of hydrocarbons from wastewater treatmentplants in Vienna has taken place. 相似文献
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Bernhard Brantner Helga Fierlinger Hans Puxbaum Axel Berner 《Water, air, and soil pollution》1994,74(3-4):363-384
Cloudwater and wet precipitation (snow) samples were collected at Mount Sonnblick during two field campaigns in May and November 1991. A newly designed active cloud water samples was used. Concentrations of major anions, cations and carboxylic acids were determined. Cloudwater and wet precipitation samples were generally more acidic in the warm season than in the cold season. Average cloudwater pH was 4.2 in May and 4.5 in November, average pH in snow was 4.4 in May and 5.1 in November. Average levels for sulfate (May: 96 μeq L?1, November: 64 μeq L?1) and nitrate (May: 27 μeq L?1, November: 32 μeq L?1) in cloudwater at SBO (3 km altitude) were considerably lower than at high mountain sites (0.9–2 km altitude) in the Eastern U.S.A. Cold season levels of sulfate in cloud water at SBO were as low as cloud water levels observed in Alaska. Equivalent concentrations of sulfate, nitrate and ammonium in snow precipitation were basically lower or equal compared to cloudwater but showed higher concentrations and stronger acidity in both phases in May than in November. Cloud to snow ratios for major ions were higher in November showing a wider spread than in May. Average cloud to snow ratios for sulfate were 2.4 in May and 3.5 in November. For nitrate the ratio was 1.7 in May and 2.1 in November. The lower cloud to snow ratios for nitrate are explained by the ability of the ice phase to scavenge nitric acid. Cloud to snow ratios were similar to measurements from the Swiss Alps and generally equal or lower than high elevation cloud to rain ratios from the U.S.A. Cloud to snow ratios for sulfate were used to reconstruct the mixing ratio of sublimation grown ice phase and cloud water droplets during the riming process of the ice particles in the seeder-feeder mechanism. The mixing ratio of ice phase and cloud droplets was estimated to be 1.4 in May and 2.5 in November. Sulfate to nitrate ratios were higher in cloud water than in snow and within the range of values found in North America. Generally, sulfate was more concentrated than nitrate at an equivalent basis for both cloudwater and rainwater. Total equivalent concentrations of acetate were generally higher than those of formate which is in contrast to measurements at remote high elevation sites in the U.S.A. 相似文献
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