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The concentrations of dissolved chromium in seawater of the Bohai Gulf vary from trace to 1.6 μg /1 while those of particulate chromium from trace to 8.66 μg/1, indicating that the concentration of chromium in seawater of nearshore and estuary in the Bohai Gulf is higher than that of offshore, and reflecting the effects of estuarine and terrestrial pollutions. Observation data indicate that there is a positive correlation between particulate chromium and COD.The result shows that organic matter in seawater has a strong ability to combine chromium. When particulate chromium meets with seawater in estuary, it gradually settles down to sea-bottom sediments. Ratio of particulate chromium to total chromium in the Bohai Gulf yields a higher value, exceeding 90% in estuarine area, i.e. particulate chromium is a predominant form in seawater of the Bohai Gulf. 相似文献
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渤海西南部潮间带沉积物中的重金属 总被引：5，自引：0，他引：5
用石墨炉原子吸收分光光度法测定了渤海潮间带沉积物中Zn,Cu,Pb,Cd,Cr和Ni。研究结果表明,渤海西南部潮间带沉积物中重金属含量基本正常,但Zn的污染较为明显,可能与油田排污有关。黄河口重金属含量从高潮带向低潮带逐渐降低。本区沉积物具有相似的地球化学特性。沉积物中重金属含量与有机质含量密切相关,它们易与有机质结合,而沉降至底质。 相似文献
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长江口及其邻近海域铬的行为 总被引：3，自引：1，他引：3
作者于1985年8月,11月,1986年3月及1987年4月进行长江口海域铬的形态调查,表明该海域铬的分布趋势是江口高、外海低,并随离岸距离的增加而递减。枯水期,在3l°30′N附近出现外海低铬水舌向岸方向延伸。颗粒铬Cr(P)是铬的主要存在形态,但在夏季则是总溶解铬Cr(S)和三价铬Cr(Ⅲ)为主要存在形态。六价铬Cr(VI)占Cr(T)比率很低,所以是最次要形态,而Cr(Ⅲ)在溶解态中则是主要形态。黄浦江水中Cr(VI)含量要高于长江水,说明黄浦江存在着明显的铬污染。夏、秋季长江口物理、化学条件剧变时发生颗粒铬的迁移。 相似文献
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黄河及其河口区铬的形态 总被引：1，自引：0，他引：1
对黄河下游及河口区铬的测定结果表明,丰水期不同形态铬的含量均比枯水期高,铬含量的分布与河流径流量、排污量有关。形态研究表明,河水中以颗粒铬[Cr(P)]为主,三价铬[Cr(Ⅲ)]次之,六价铬[Cr(Ⅵ)]最次。近河口区域与河水相似,但在远离河口区域,丰水期Cr(Ⅲ)成为主要形态,Cr(Ⅵ)仍为最次要形态。Cr(Ⅲ)与COD,Cr(P)与COD,及Cr(P)与悬浮体(TSM)均有较好的相关性。Cr(Ⅵ)在河口条件下,可被有机物还原,并被悬浮物吸附而转入沉积物。 相似文献
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Research of chromium speciation in the Bohai Gulf showed that content of particulate chromium in estuarine area rea ched more than 90%, so it is an existing dominant speciation in the Bohai Gulf. Ratio between trivalent chromium to total dissolved chromium is over 80%, whereas contents of hexavalent chromium is very low. The mean content of Cr (Ⅲ) is 5.6 times higher than that of Cr (Ⅵ). Thus trivalent chromium is the prinicipal speciation of valency state of chromium in the Bohai Gulf.Under the physical and chemical condition at the eatuary transferring mechanism of chromium in seawater of Bohai Gulf is done by absorption, complexion and subsequent settlement in the sediments of trivalent chromium by suspended matter. Therefore suspended matter plays a part on the purification of sewater for this gulf. 相似文献
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