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1.
Analysis of Zn, Cu, Pb, Co, Cr, Li, Ni, K, Al, Fe extracted by 1 mol/L HCl or 0.5 mol/LHCl/H_2O_2, showed concentrations of Zn, Cu, Pb, Co, Cr, Fe, Ni were significantly correlated with Li, Al,K, and clay. Two methods are used to indicate the background value of the non-residual phase of elementsin sediments, and are the same as the methods used to indicate the background value of totalconcentrations in sediments. The first method uses correlograms and regression equations,the second usesthe mean element concentrations normalized with grain size. Li, Al, K can be used as reference elements to determine the background value of Zn, Cu, Pb, Co,Cr, Ni, Fe, while the clay concentration's correlation with some extractable concentrations can be used tocalculate the background value of the non-residual phase of elements as a percentage of clay concentrationin the sediments. Based on this study, the concept of using the background value of the non-residualphase of elements to compare the pollution level in differ 相似文献
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DISTRIBUTIONS OF TOTAL, INORGANIC AND ORGANIC PHOSPHORUS IN THE SEDIMENTS NEAR THE HUANGHE RIVER ESTUARY 总被引：1，自引：0，他引：1
For some hundred surface sediment samples from five cores taken in two cruises near the Huanghe River Estuary, total phosphorus (TP (.inorganic phosphorus (IP (and organic phosphorus (OP)were determined.On the average, 527×10-6, 455×10~6 and 72×10-6 were found for TP,IP and OP for the surface sediments taken in the two cruises. The distribution of OP and IP was controlled by the sample particle size: OP content increased with the decreasing of the sample particle size, while the maximal value of IP was found in the silt fraction due to the existence of apatite in our samples. Vertical distributions reflected well the channel change of the Huanghe River. Results from the multiple regressions between the three forms of phosphorus and the percentages of different particle size agreed well with the analytical data. 相似文献
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DMS (dimethylsulfide), a breakdown product of cellular solutes of many species of macroalgae andphytoplankton plays an important role in regulating global climate and counteracting partly the "greenhouse" effect.In this paper, the advance and prospects of DMS study are reviewed and discussed with respectto DMS sample storage, measurement and importance in regulating global climate and the acidity ofrain and aerosol. 相似文献
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ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｔｏｘｉｃｉｔｙｏｆｈｅａｖｙｍｅｔａｌｓｒｅｌｅａｓｅｄｉｎｔｏｔｈｅｅｎｖｉｒｏｎｍｅｎｔｈａｓｒｅｃｅｎｔｌｙｔｒｉｇｇｅｒｅｄａｎｕｍｂｅｒｏｆｓｔｕｄｉｅｓａｉｍｉｎｇａｔｔｈｅｒｅｍｏｖａｌｏｆｍｅｔａｌｉｏｎｓｆｒｏｍａｑｕｅｏｕｓｓｏｌｕｔｉｏｎｓ (ＦｏｕｒｅｓｔａｎｄＶｏｌｅｓｋｙ ,1 997;ＦｅｈｒｍａｎｎａｎｄＰｏｈｌ,1 993 ;ＫｕｙｕｃａｋａｎｄＶｏｌｅｓｋｙ,1 989) .Ｉｔｗａｓｆｏｕｎｄｔｈａｔｔｈｅａｃｃｕｍｕｌａｔｉｏｎｏｆｈｅａｖｙｍｅｔａ… 相似文献
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超临界流体分离技术及其在环境研究和治理上的应用 总被引：2，自引：0，他引：2
１ 超临界流体及超临界流体提取所谓超临界流体是指某些气体或液体在一定的温度和压力下处于似液非液似气非气状态时的流体。此时的流体同时具备液体与气体的性质,气相和液相具有相同的密度,其比重也往往介于气体与液体之间。在超临界状态下,随温度、压力的变化,流体的密度也随之变化。超临界流体具备一些常规流体所不具备的性质,人们正是利用这些特殊性质而使得它们在科研与生产中得到越来越广泛的应用。超临界二氧化碳由于具有下列优点而应用最为广泛：（１）低的超临界温度（有利于萃取热稳定性差的物质）;（２）非易燃;（３）易… 相似文献
6.
黄河口沉积物中无机磷酸盐的存在形态 总被引：31，自引：0，他引：31
本文对1989年5月和8月采集的黄河口附近浅海表层沉积物及柱状沉积物进行了磷酸盐形态(吸附态磷、铝磷、铁磷、闭蓄态磷和钙磷)的分析,并对几个样品的不同粒级也分别作了形态分析。结果表明,钙磷占无机磷的大部分;闭蓄态磷次之;铝磷和吸附态磷再次之;铁磷含量极微。除钙磷(由于有矿物磷的存在)在粉砂粒级中含量最高外,其它各形态磷的含量均随粒度变细而增高。 相似文献
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养殖环境对对虾生长及病原体传播的影响 总被引：9，自引：0，他引：9
８０年代以来 ,我国的对虾养殖业得到了空前的发展 ,其产量１９８８年曾超过２０００００ｔ,一度成为世界第一大对虾养殖国。但是由于盲目发展、缺乏科学管理 ,再加上对虾养殖单位及个人只顾眼前利益、不重视基础设施建设 ,盲目提高养殖密度、增加投饵量 ,这种严重违背自然规律的做法遭到了大自然强有力的报复 :自９０年代以来虾池的水质和底质环境严重恶化导致水体富营养化、赤潮频繁发生。这不仅对养殖业自身造成危害 ,而且还污染了周围的浅海水体 ,从而反过来又影响养殖业 ,形成恶性循环。其结果给细菌、病毒造就了良好的生长环境 ,虾病… 相似文献
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黄河口沉积物对磷酸盐的吸附与释放 总被引：44，自引：2，他引：44
本文对黄河口典型沉积物进行了吸附磷及释放磷的研究,结果表明黄河口地区浅海沉积物对磷的释放极少.阴离子表面活性剂的存在能降低对磷的吸附能力,溶液pH的增大对吸附量有增大的作用,硝酸盐的存在不影响沉积物对磷的吸附.沉积物吸附大量磷后的再释放是缓慢的.经测定,沉积物吸附/解吸平衡点一般为0.24～4.27μmol/dm3,此值一般高于底层水磷浓度,因此我们推测除粗颗粒样品外,黄河口地区浅海沉积物有向上覆水释放磷的倾向. 相似文献
10.
林荣根 《中国海洋湖沼学报》1994,12(2):106-113
The degradability of particulate organic matter(POM)in the Gironde Estuary(France)was measuredusing the incubation technique.The influence of sample treatment and incubation conditions on the re-sults was evaluated.A mathematical model was successfully used to describe the various degradationcurves.Results showed that the upstream POM had very high degradability;the central estuaryPOM had low degradability;and that the mouth POM degradability was between that of central POM(low degradability)and marine POM(high degradability). 相似文献