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The uptake and accumulation of the traffic-related platinum group elements (PGE) Pt, Pd and Rh by the aquatic fauna was investigated. Zebra mussels, eels and barbels were maintained in water containing either road dust or ground catalytic converter material. Following the exposure, samples of fish liver and kidney, as well as the soft tissues of the mussels, were analysed. Our results revealed that all three catalytic noble metals were accumulated by aquatic organisms. The highest bioavailability was found for Pd, followed by Pt and Rh. The concentration factor of Pd forDreissena polymorpha was 5 times higher compared with Pd and only 6 times lower than the essential element Cu. With regard to the increasing emission of Pd the level of this metal has to be monitored very carefully in the environment. 相似文献
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For phosphorus (P) recovery from wastewater, the effect of humic substances (HS) on the precipitation of calcium phosphate was studied. Batch experiments of calcium phosphate precipitation were undertaken with synthetic water that contained 20 mg/L phosphate (as P) and 20 mg/L HS (as dissolved organic carbon, DOC) at a constant pH value in the range of 8.0-10.0. The concentration variations of phosphate, calcium (Ca) and HS were measured in the precipitation process; the crystalline state and compositions of the precipitates were analysed by powder X-ray diffraction (XRD) and chemical methods, respectively. It showed that at solution pH 8.0, the precipitation rate and removal efficiency of phosphate were greatly reduced by HS, but at solution pH ≥9.0, the effect of HS was very small. The Ca consumption for the precipitation of phosphate increased when HS was added; HS was also removed from solution with the precipitation of calcium phosphate. At solution pH 8.0 and HS concentrations ≤3.5 mg/L, and at pH ≥ 9.0 and HS concentrations ≤ 10 mg/L, the final precipitates were proved to be hydroxyapatite (HAP) by XRD. The increases of solution pH value and initial Ca/P ratio helped reduce the influence of HS on the precipitation of phosphate. 相似文献
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Marijan Cubelic Richard Pecoroni Jörg Schäfer Jörg-Detlef Eckhardt Zsolt Berner Doris Stüben 《Environmental Sciences Europe》1997,9(5):249-258
Contents and distribution of platinum-group-elements (PGE) in soils caused by automobile emissions were investigated at three transects perpendicular to the road at various depths. Concentrations of platinum, rhodium and palladium were determined by ICP-MS after separation and preconcentration by nickel-sulphide fire-assay. Platinum contents in roadside soils range from 250 μg/kg to the local background values which are below 0.5–0.8 μg/kg. Ratios of platinum and rhodium (about 6∶1) are similar to the ratios in catalytic converters. There is evidence for a significant correlation of PGE input and local parameters such as traffic-conditions, distance from the trafficlane, prevailing wind direction, and barriers such as vegetation or morphology. 相似文献
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Summary 2-methyl-1,4-benzoquinone as a target compound of the tergal gland secretion of the rove beetle,Aleochara curtula, was quantified from the reservoirs of individual beetles. Males store less secretion than females, and they evaporate more of the secretion as measured by adsorption from the air (closed-loop-stripping-analysis). The amount of emitted quinone is increased during aggressive interactions of rival males. The pulsed emission of the secretion during aggression is demonstrated by a novel technique combining observation of behavior with the on-line measurement of target fragment ions by mass-spectrometry (tandem bioassay — mass fragmentography). The emission of the secretion is used as a weapon in combats between males and may result in the repulsion of subordinate males from the mating site, but may also serve to mimic females chemically in order to avoid aggressive encounters. 相似文献
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Distribution of selected heavy metals and rare earth elements in surficial sediments from the polish sector of the Vistula Lagoon 总被引:1,自引:0,他引:1
P. Szefer G. P. Glasby D. Stüben A. Kusak J. Geldon Z. Berner T. Neumann J. Warzocha 《Chemosphere》1999,39(15):1200-2798
The concentrations of 22 trace elements plus the rare earth elements (REE) were determined in the <63 μm fraction of surficial sediments from the Polish sector of the Vistula Lagoon by ICP-MS. For the anthropogenically-enriched elements, the mean element enrichment factors (EF's) decrease in the sequence Ag (9.9) > Sb (7.5) >As (5.8) ≥ Cd (5.2) > Pb (3.7), albeit with large variability in concentration in the sediments from one station to another. These observations demonstrate that sediments from the Vistula Lagoon are locally polluted by these anthropogenically-derived elements. Plots of NASC-normalized REE data show that the REE patterns of the sediments have not been significantly modified during transport from their source with only a minor depletion of the heavy rare earth elements (HUE) compare to the light rare earth elements (LREE). The lack of any significant anomalies for Ce and Eu indicates that redox processes have not played a major role in modifying the distribution of the REE. Factor ananalysis of the compositional data shows that sediments from the Polish sector of the Vistula Lagoon can be divided into three main groups depending on the geographical location and the degree of contamination by heavy metals. 相似文献
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Identifikation der kfz-bürtigen Schadstoffbelastung mit Hilfe der Verh?ltnisse der stabilen Isotope von Kohlenstoff und Schwefel 总被引:1,自引:0,他引:1
Tobias Türcke Stefan Norra Doris Stüben Zsolt Berner und Markus Leosson 《Umweltwissenschaften und Schadstoff-Forschung》1999,11(3):127-133
Zusammenfassung Reifen-, Ru?-, Motoren?l-, Asphalt-, Plastik- und Lackproben aus dem Stra?enverkehr wurden auf ihre Kohlenstoff- und Schwefel-isotopenverh?ltnisse
mit dem Ziel untersucht, die Frage zu beant-worten, ob diese Isotopenverh?ltnisse als Indikatoren für die Belastungssituation
und die Schadstoffquellen bei der Untersuchung von stra?ennahen B?den eingesetzt werden k?nnen. Die δ11C-Werte der technischen Substrate lagen zwischen-30‰ und-18‰ relativ zum PDB-Standard, Dabei zeigte sich aufgrund der unterschiedlichen
Herstellungsverfahren eine deutliche Abgrenzung der Substrate untereinander. Asphalt hatte Werte zwischen-23 und-18‰, Ru?
zwischen -27 und -22‰ Die Ru?proben unterschieden sich je nach Art des verwendeten Kraftstoffs. Plastik, Lack und Motor?le
zeigten ?hnliche δ13C-Werte, die zwischen-30 und-27‰ lagen. Reifen haben relativ konstante δ13C-Werte um -26‰ Der Einflu? des Stra?enverkehrs auf die δ13C-Werte im Stra?ensediment und in stra?ennahen B?den konnte anhand verschiedener Kohlenstoffspezies an einem Transekt an einer
Landstra?e aufgezeigt werden. Ein Vergleich mit verkehrstypischen Schwermetallemissionen ergab bei einzelnen Kohlenstoffspezies
einen ?hnlichen Verlauf der Schwermetallkonzentrationen und der δ13C-Werte.
Die δ34S-Werte lagen zwischen -6 und +8‰ relativ zum CDT-Standard. Eine Abgrenzung der Substrate in ihren δ14S-Werten war hierbei nicht m?glich.
相似文献
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Effects of solution conditions on the precipitation of phosphate for recovery. A thermodynamic evaluation 总被引:16,自引:0,他引:16
To understand the effects of solution conditions on the precipitation of calcium phosphates from wastewater for recovery, a computer programme PHREEQC was employed to calculate the speciation and saturation-index (SI) with respect to hydroxyapatite of a chemically defined precipitation system, which contains phosphate of 1–200 mg P/l, with Ca/P molar ratios of one to 10 times of the stoichiometric calcium to phosphorus molar ratio of hydroxyapatite, at a pH range of 7.0–11.0. The results show that the SI is respectively the logarithmic function of the phosphate concentration and the calcium concentration, increasing with the increase of either of them; the SI is a polynomial function of the solution pH value and increases with its increase, and the effect of solution pH value is due to its influence on base uptake of the precipitation reaction and the speciation of phosphate and calcium ions; the SI is also a logarithmic function of the solution ionic strength but decreases with its increase; at the temperature range of 5–30 °C the SI increases linearly with solution temperature and the effect of temperature is also due to its influence on the speciation of phosphate and calcium ions. 相似文献
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Tobias Türcke Stefan Norra Doris Stüben Zsolt Berner Markus Leosson 《Environmental Sciences Europe》1999,11(3):127-133
Different sources of traffic immissions (tyres, soot, oil, asphalt, plastic, paint) were analysed for stable carbon and sulphur isotope ratios. The aim of this study is to investigate whether these isotope ratios can be used to evaluate the environmental impact of traffic immitted harmful substances in roadside soils. The δ13C values of technical materials are between -30‰ and -18‰ (PDB). They can be distinguished by their δ13C value because of specific production methods. The δ13C value of asphalt is between -23 and -18‰, soot shows values from -27 to-22‰ Moreover, soot of different fuel have different carbon isotope ratios. Plastic, paint and oil have similar δ13C from -30 to -27‰ Carbon isotope ratios of automobile tyres are around -26‰ Traffic impact on the carbon isotope composition is reflected in δ13C values of various carbon spezies found in street sediments and road side soils. These δ13C values correlate to concentrations of lead and platinum. Although δ34S values of technical materials are between -6 and +8‰ it was not possible to characterise samples according to their Sulphur isotopic compostion. 相似文献
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The versatility and efficiency of the VUV photolysis of water as an “Advanced Oxidation Procedure” for the light-induced oxidative degradation of atrazine as a pollutant of surface and ground waters is evaluated. The oxidation of atrazine using TiO2 as a photocatalyst has been reported to produce almost stoichiometric amounts of cyanuric acid. Mineralization to CO2, water and inorganic nitrogen containing ions occurred to a very low extent implying that cyanuric acid is resistant to further degradation under the chosen experimental conditions. Our present results show that in oxygen saturated solutions 50% of the initial atrazine is converted to cyanuric acid, whereas only 10% of the initial atrazine is isolated as cyanuric acid in argon saturated solutions. The results indicate that mineralization is more efficient in not strictly oxidative reaction media. 相似文献