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981.
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Untersuchungen anMyriophyllum verticillatum, Potamogeton natans undNymphaea alba in Seen unterschiedlicher Trophiestufen best?tigen, da? in humin- und fulvo-s?urereichen Seen auch bei erh?htem Schwermetallangebot bei einer Reihe von metallen niedrigere Biokonzentrationsfaktoren als in huminstoffarmen Seen zu verzeichnen sind.  相似文献   
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Sludge from gullies, on two types of streets with different traffic intensity, was investigated using two recommended EU methods for leachability testing of waste: a two-stage batch test and an up-flow percolation test. The main purpose of this investigation was to gain more knowledge about these leaching test methods to be able to make future decisions on the general applicability of the proposed tests. A number of parameters were determined in the sludge as well as in the eluates obtained from the two leaching tests. These include pH, conductivity, dissolved organic carbon and inorganic ions as chloride ions. A number of metals as Cd, Cr, Cu, Hg, Ni and Zn, were determined by inductive coupled plasmamass spectrometry and organic compounds were screened by high performance liquid chromatography-diode array UV detection and gas chromatography-mass spectrometry. It was found that the concentrations of metals and organic compounds in the sludge were several orders of magnitudes higher than the actual eluate concentrations. For all metals the concentrations were well below the proposed limit values for non-hazardous waste included in the Council decision document 2003/33/EC. Generally, concentrations obtained in batch test were equal or higher than from percolation tests. The repeatability of the percolation and the batch test were in average 28 and 17%, respectively.  相似文献   
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The present study has been undertaken to evaluate the adsorption in batch mode of a disperse dye (Disperse Blue SBL) by poorly crystalline hydroxyapatite synthesized by coprecipitation between Ca(NO_3)_2 and (NH_4)_2HPO4 reagents in aqueous solution at room temperature. The adsorption experiments were carried out to investigate the factors that influence the dye uptake by the adsorbent, such as the contact time under agitation, adsorbent dosage, initial dye concentration, solution temperature, and pH. The e...  相似文献   
990.
In Nokia city about 450,000 l of treated sewage water was for 2 days allowed to run into the drinking water supplies of the city due to a personal error of one employee. Within the next 5 weeks about 1,000 people sought care at the municipal health centre or regional hospital because of gastroenteritis. Here we report the results of viral analyses performed by gene amplification assays from the earliest water and sewage samples as well as from close to 300 patient samples. The contaminating treated sewage was shown to harbour several enteric viruses known to cause acute gastroenteritis. Likewise, the drinking water sample was positive for noro-, astro-, rota-, entero- and adenoviruses. Noroviruses were also found in 29.8% of stool samples from affected patients, while astro-, adeno-, rota- and enteroviruses were detected in 19.7, 18.2, 7.5 and 3.7% of the specimens, respectively. An erratum to this article can be found at  相似文献   
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