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The major water-soluble arsenic compound in the Alaskan king crab, the Alaskan snow crab, and the Dungeness crab was identified as arsenobetaine by HPLC/ICP analysis. This technique is suitable for the identification and quantitative determination of naturally occurring organic arsenic compounds in purified and partially purified extracts from biota.  相似文献   
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Buchpr?sentationen

Stoffhaushalt von Auen?kosystemen: B?den und Hydrologie, Schadstoffe, BewertungenHrsg: K. Friese, B. Witter, G. Miehlich, M. Rode Verlag: Springer Verlag, Heidelberg, 2000, 434 S., 196 Abb., 79 Tabellen, ISBN 3-540-67068-8, DM 169,-  相似文献   
427.
Water affordability is determined by the percentage of income households that must allocate to municipal water services, while factoring in essential or basic needs water use. With the rise in water prices reported in most areas of the country along with somewhat stagnant income growth—a combination that suggests ceteris paribus—more of a household's disposable income is being spent on water services. This paper adds to the discussion in three ways. First, given the lack of a consistent definition for “affordability” and the subjective connotation associated with such a term, we develop and compare five different water expenditure ratios, including two different measures of water for essential needs, as well as measures for indoor, efficient, and actual water use. Second, because of the granularity of our data, we illustrate how such “affordability” measures can vary significantly within a water district and thus highlight how using district- or county-level income measures can mask the degree to which affordability is an issue for households living in low-income block groups. Our results indicate that the choice of income measure and type of water service use can influence affordability measures substantially.  相似文献   
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Golden Horn is an estuary in Istanbul. It has connection with Marmara Sea directly and with Black Sea via Bosphorus, and was polluted by different kinds of industrial plants up to 1999. In addition to this, municipal wastewater of around one million people has been discharged to here. Greater part of the estuary was almost blocked off by sediment islands. Extensive effort was spent to dredge sediment in 1999. This created quite a convenient condition for aquatic medium in the estuary.In this research, the variations of chemical compositions of sediment bed were investigated to get clue about ecological conditions of the estuary. For that purpose, sediment samples were taken from 6 stations along the estuary in 2001, 2003 and 2004. The sediment samples were analyzed for inorganic and organic constituents. Meanwhile, water samples (from the surface and just above benthic mass) were also taken from the same 6 places and they were analyzed to verify the data from sediment samples. By this way, correlations between sediment mass and water body were determined.  相似文献   
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