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21.
Jürgen Maguhn Andrea Wimschneider Raimund Brotsack Peter Spitzauer Dieter Freitag Antonius Kettrup 《Environmental Sciences Europe》2000,12(5):259-268
The airborne immissions in the eastern surroundings to the new Munich airport have been investigated by means of different analytical methods between 1992 and 1995. For a detection of environmental impacts, bioindicators were applied to determine the pollution by PAH and to quantify the pollution by photooxidants. In addition, the PAH content in the upper soil layer was determined. During high pressure weather periods in summer the actual air pollution was investigated in the course of seven measuring campaigns. The PAH pollution of the soil is typical for rural background sites with highest concentrations in the close vicinity of busy roads, and exhibits no temporary trend. The actual input of PAH does not differ from the typical situation of rural regions in Bavaria at any measuring sites at all. Road traffic can be identified as the main PAH source in summer, whereas the considerably higher pollution in winter can be related to domestic heating. The pollution by photooxidants was found to be rather homogeneous throughout the eastern surroundings to the airport, being lowest at the sites directly influenced by road traffic. The pollution by volatile hydrocarbons at a busy road junction in the city of Erding is considerably higher than in the rural vicinity of the airport. The concentrations exhibit distinct daily courses which, among other things, can be related to atmospheric photooxidation. The hydroperoxides as secondary air pollutants exhibit an inverse course similar to that of ozone, with maximum values in the afternoon. 相似文献
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Wijnhoven S van der Velde G Leuven RS Eijsackers HJ Smits AJ 《Environmental pollution (Barking, Essex : 1987)》2006,140(3):444-452
Turbation is hypothesized to affect the redistribution of heavy metals in polluted floodplain soils by effects on mobility. This hypothesis was tested in microcosms by turbation of zinc-spiked sediment top layers. Manual turbation caused a fast decrease of the zinc content in the upper 15 cm of the soil, even though turbation was only applied to the upper two centimetres. It was especially zinc attached to colloid and organic matter particles that was redistributed from the top layer. Percolation processes resulted in the attached zinc being drained to depths of more than 15 cm. The decrease in zinc content of the topsoil was even stronger in combination with inundation. No indications were found for the redistribution of zinc as a result of an increase of the extractability with 0.01 M CaCl2 or changes in pH. The findings suggest that mechanical turbation and bioturbation may redistribute heavy metals from topsoils in polluted floodplains just after inundation as observed in these turbation experiments. 相似文献
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Introduction C hlorinated volatile organic com pounds(C V O C s) w ere released to the atm osphere as flue gases from various industrial processes. C hlorinated hydrocar- bons have been w idely accepted as solvents and chem ical interm ediates in the m an… 相似文献
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Jürgen Maguhn Andrea Wimschneider Raimund Brotsack Peter Spitzauer Dieter Freitag und Antonius Kettrup 《Umweltwissenschaften und Schadstoff-Forschung》2000,12(5):259-268
Zusammenfassung Die Immissionsbelastung im ?stlichen Umland des neuen Münchner Flughafens wurde im Zeitraum von 1992 bis 1995 mit Hilfe einer
Reihe unterschiedlicher Messmethoden untersucht. Für die wirkungsbezogene Erfassung von Umwelteinflüssen wurden Bioindikatoren
zur Bestimmung der PAK-Belastung und zur Quantifizierung der Photooxidantienbelastung eingesetzt. Darüber hinaus wurde der
PAK-Gehalt des Oberbodens bestimmt. Die aktuelle Luftbelastungssituation wurde w?hrend photochemisch aktiver Wetterlagen im
Sommer im Rahmen von 7 Intensivmesskampagnen untersucht. Die Bodenbelastung mit PAK liegt im Bereich der für l?ndliche Regionen
typischen Hintergrundwerte mit den h?chsten Konzentrationen in der N?he stark befahrener Stra?en und weist keinen zeitlichen
Trend auf. Auch der aktuelle PAK-Eintrag liegt an allen Standorten in einem für l?ndliche Regionen in Bayern typischen Bereich.
Als Hauptemittent wird im Sommer der Kfz-Verkehr identifiziert, w?hrend die deutlich erh?hte Belastung im Winter auf den Hausbrand
zurückgeführt werden kann. Die Photooxidantien-belastung zeigt im Flughafenumland keine ausgepr?gten Unterschiede, sie ist
an den durch Stra?enverkehr beeinflussten Standorten jedoch am geringsten. Die Konzentrationen leicht flüchtiger Kohlenwasserstoffe
sind an einer verkehrsreichen Stra?enkreuzung in Erding deutlich h?her als im l?ndlichen Flughafenumland. Sie zeigen ausgepr?gte
Tagesg?nge, die u.a. auf den luftchemischen Abbau zurückzuführen sind. Die Hydroperoxide als sekund?re Luftschadstoffe weisen
einen gegens?tzlichen Verlauf auf, der dem des Ozons mit nachmitt?glichem Maximum ?hnelt.
Online-First: 23. August 2000 相似文献
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To study the transport mechanism of hydrophobic organic chemicals (HOCs) and the energy change in soil/solvent system, a soil leaching column chromatographic (SLCC) experiment at an environmental temperature range of 20-40 degrees C was carried out, which utilized a reference soil (SP 14696) packed column and a methanol-water (1:4 by volume ratio) eluent. The transport process quickens with the increase of column temperature. The ratio of retention factors at 30 and 40 degrees C (k'30/k'40) ranged from 1.08 to 1.36. The lower enthalpy change of the solute transfer in SLCC (from eluent to soil) than in conventional reversed-phase liquid chromatography (e.g., from eluent to C18) is consistent with the hypothesis that HOCs were dominantly and physically partitioned between solvent and soil. The results were also verified by the linear solvation energy relationships analysis. The chief factor controlling the retention was found to be the solute solvophobic partition, and the second important factor was the solute hydrogen-bond basicity, while the least important factors were the solute polarizability-dipolarity and hydrogen-bond acidity. With the increase of temperature, the contributions of the solute solvophobic partition and hydrogen-bond basicity gradually decrease, and the latter decreases faster than the former. 相似文献
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The aim of this work was to evaluate the effect of linear alkylbenzene sulfonate (LAS, 200 mg l(-1)) on the fate of phenanthrene in a model ecosystem "water-lava-hydrophytes-air". The experiments were conducted using two closed cultivation chamber systems. Rushes (Juncus effesus) were selected as a representative hydrophyte. Five hundred micrograms per liter of phenanthrene in a culture solution containing a 14C-activity of 75 microCi per chamber was applied (i) to investigate the degradation of the labeled test substance and the transfer processes within the system; (ii) to determine the mass-balance possible and (iii) to detect the occurrence of volatile test substances, their volatile metabolites and the degradation end-product CO2 in the gas phase. Most of the applied 14C-activity was found in the plant (41-45%), in which approximately 95% was associated with plant roots and approximately 5% with shoots. The 14C-activity recovered in the form of VOCs and CO2 was measured in lava (18-29%, 8-11%), and in the culture solution (10-14% and 1%), respectively. Majority of the applied 14C-activity existed in two forms, i.e. (1) polar metabolites (26%), of which 91% were found in plant roots, and (2) un-extractable residues (23%), most of which were in plant roots (40%) and bounded to lava (58%). The presence of LAS significantly increased the volatilization of phenanthrene and its metabolites, inhibited its mineralization and decreased the level of 14C-activity in lava. Moreover, LAS reduced the phenanthrene level in plant roots. 相似文献