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1.
The elements Al, Cd, Co, Cu, Ni and Zn were concentrated from seawater using tetraethylenepentamine resin and analysed by atomic absorption spectrophotometry. The spatial distribution of these elements in the northwest Atlantic Ocean is discussed with respect to possible riverine inputs to the area from Puerto Rico.  相似文献   

2.
This is the first study of the flocculation of dissolved Fe, Al, Mn, Si, Cu, Pb and Zn during mixing in Zhujiang Estuary, based on the experiment on a series of solutions of salinities ranging from 0 to 24 by mixing the Zhujiang water near Zhongshan University and the seawater in Wan-shan Archipelago area. The mechanism of flocculation of the 7 elements is explored, and the effects of time, acidity and temperature on flocculation are discussed. The results show that the flocculation rates of Fe and Pb in the Zhujiang water are almost a hundred per cent, while that forCu reaches 76%; for Mn, 51%; for Al, 48%; for Zn, 28%; and for Si, 1.2%, indicating that Si is conservative.  相似文献   

3.
The oceanic biogeochemical cycles of many trace elements are dominated by their association with the growth, death, consumption and sinking of phytoplankton. The trace element content of marine phytoplankton reflects nutritional status, species composition, surface area to volume ratios, and interactions with bioactive and toxic elements in the ambient seawater. Despite the ecological and environmental importance of trace element assimilation by autotrophs, there are few modern measurements of trace elements in phytoplankton assemblages from the natural environment. Here we introduce a new method for collection and analysis of size-fractionated particulate samples from practical seawater volumes. We pay particular attention to accurate determination of trace element filter blanks which are typically the limiting factor for analysis of such samples. Metals were determined at very low detection limits by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for 11 elements (Ag, Al, Cd, Co, Cr, Cu, Fe, Mn, U, Zn and P, which is used as a biomass normalizer) in three types of polymer filters (0.45, 5.0, and 53 μm pore size) and a quartz fiber filter (0.8 μm pore size). To place these new determinations in a practical context, results are presented for a vertical profile of samples filtered from 1–4 l of coastal seawater (0.3–1.0 mg total solid dry weight) at a station off central California. The results demonstrate that the blanks of the evaluated filter types, precleaned appropriately, are sufficiently low to allow accurate determination of the trace metal content of three size-classes of phytoplankton. At the Pacific station, measured phytoplankton Zn content (as Zn/P) agrees with values predicted from single-species culture studies growing at seawater Zn concentrations expected for coastal waters. The new method has utility as a generally applicable and simple size fractionation technique, and allows determination of natural and pollutant elements in small samples of phytoplankton and particles in coastal, estuarine and offshore marine regimes.  相似文献   

4.
能量色散X射线荧光光谱仪是一种较为先进的化学分析仪器。我们应用此仪器,采用谱线背景作内标的方法对海洋沉积物中的Cu、Zn、Pb、Ba元素进行了测定,结果比较令人满意。本方法的准确度要优于重量法、比色法,与原子吸收法相比,本法不需要经过萃取分离处理样品,方法简便、快速。因此,本方法适用于大批量样品和多元素的快速测量。  相似文献   

5.
A simple and rapid coprecipitation method for the determination of several trace metals in seawater is presented. These metals are coprecipitated with lanthanum hydroxide, the precipitate is dissolved, and then the metals are determined by atomic absorption spectrometry. Lanthanum hydroxide was chosen as a coprecipitant for the following reasons, (a) lanthanum hydroxide has a sufficiently low solubility and forms an easily filterable flocculate at about 80C, and (b) lanthanum has an absorption wavelength that is sufficiently separated from those of the other elements to be analysed, i.e., Mn, Fe, Ni, Cu and Zn. Experimental results show that these metals are coprecipitated by the present method with excellent recoveries.  相似文献   

6.
Ferromanganese(Fe-Mn) crusts are potential archives of the Cu and Zn isotope compositions of seawater through time. In this study, the Cu and Zn isotopes of the top surface of 28 Fe-Mn crusts and 2 Fe-Mn nodules were analysed by MC-ICP-MS using combined sample-standard bracketing for mass bias correction. The Zn isotope compositions of the top surface of Fe-Mn crusts are in the range of 0.71‰ to 1.08‰, with a mean δ~(66) Zn value of 0.94‰±0.21‰(2 SD, n=28). The δ~(65) Cu values of the top surface of Fe-Mn crusts range from 0.33‰ to0.73‰, with a mean value of 0.58‰±0.20‰(2 SD, n=28). The Cu isotope compositions of Fe-Mn crusts are isotopically lighter than that of dissolved Cu in deep seawater(0.58‰ vs. 0.9‰). In contrast, the δ~(66) Zn values of Fe-Mn crusts appear to be isotopically heavy compared to deep seawater(0.94‰±0.21‰ vs. 0.51‰±0.14‰). The isotope fractionation between Fe-Mn crusts and seawater is attributed to equilibrium partitioning between the sorption to crusts and the organic-ligand-bound Cu and Zn in seawater. The Cu and Zn isotopes in the top surface of Fe-Mn crusts are not a direct reflection of the Cu and Zn isotopes, but a function of Cu and Zn isotopes in modern seawater. This study proposes that Fe-Mn crusts have the potential to be archives for paleoceanography through Cu and Zn isotope analysis.  相似文献   

7.
中国对虾体内几种重要无机元素的含量   总被引:1,自引:0,他引:1  
用原子吸收分光光度技术和比色法测定了不同体长的对虾,包括亲虾及不同组织中的K、Na、Ca、Mg、Mn、Cu、Zn、Fe和P的含量。除Mn以外,上述元素在对虾整体的含量随着体长的增加呈规律性的变化。值得注意的是,微量元素cu在对虾中的含量相当高,特别是在内脏中的含量非常高,因此存研制人工配合饵料时应注意是否会出现缺铜的问题。  相似文献   

8.
A thorough understanding of the biogeochemical cycling of trace metals in the ocean is crucial because of the important role these elements play in regulating metabolism in marine biotas and thus, the climate. However, a precise and accurate analysis of trace metals in seawater is difficult because they are present at extremely low concentrations in a high salt matrix. In this study, we report an analytical method for the preconcentration and separation of six trace metals, Fe, Ni, Cu, Zn, Cd and Pb, in seawater using a seaFAST automatic solid-phase extraction device, analysis by a triple quadrupole collision/reaction technique with inductively coupled plasma mass spectrometry (ICP-MS), and quantification by the isotope dilution technique. A small volume (10 mL) of seawater sample was mixed with a multi-element isotope spike and subjected to seaFAST procedures. The preconcentrate solution was then analyzed using the optimized collision/reaction cell mode of ICP-MS, with NH3 gas for Fe and Cd with a flow rate of 0.22 mL/min and He for Ni, Cu, Zn and Pb with a flow rate of 4.0 mL/min. The procedure blanks were 130 pmol/L, 3.0 pmol/L, 6.8 pmol/L, 37 pmol/L, 0.29 pmol/L and 0.42 pmol/L, for Fe, Ni, Cu, Zn, Cd and Pb, respectively. The method was validated using five reference materials (SLRs-6, SLEW-3, CASS-6, NASS-7 and GEOTRACE-GSC), and our results were consistent with the consensus values. The method was further validated by measuring full-water-column seawater samples from the subtropical Northwest Pacific Ocean, and our results demonstrated good oceanic consistency.  相似文献   

9.
The excretion of photosynthetically fixed carbon from cultured marine diatoms and its influence on Cu, Zn and Cd complexation in seawater was studied for three species. For each species, an isolate from oligotrophic waters was compared with an estuarine isolate. Complexation of metal was determined with the use of differential pulse anodic stripping voltammetry. Excreted material from cells in log-phase growth complexed Cu > Zn > Cd, while material derived from senescent cells complexed only Zn. The filtrates of all cultures complexed these metals comparably with natural coastal seawater. There were no appreciable differences in complexing ability within or among species, suggesting that no excretion-complexation ‘strategy’ peculiar to each ecosystem exists among these species.  相似文献   

10.
GEOCHEMISTRY OF MANGANESE NODULES IN THE NORTHERN CENTRAL PACIFIC   总被引:2,自引:0,他引:2  
The contents of Mn, Fe, Cu, Co, Ni, Pb and Zn in manganese nodules and associated pelagic sediment from the Northern Central Pacific have been measured, and the correlations between the elements of the nodules and between the chemical composition and the sedimentary environments have been analyzed. It has been found that Cu, Ni and Zn are preferentially enriched in the Mn-oxide phases while Co and Pb in the Fe-oxide phases of the nodules. The elements within the same phase are positively correlated and the elements within different phases are negatively correlated. It is concluded that the elements in the Fe-oxide phase may have directly deposited from seawater while Mn-oxide phase elements are mainly derived from interstitial waters.  相似文献   

11.
从海洋生物生态学本身的研究,生物体常量,微量元素的测定,前人已作了很多的工作。随着国防、工业及海上交通运输不断高速发展,各种工业废物大量抛入海洋,海洋污染日趋严重。为此,许多海洋学者又从海洋环境保护出发,对各个海域里的生物成分进行了监测,特别对生物体痕量金属的测定已作了大量工作[3-6]。测定的范围是广范的,从大洋到极地,从深海到岸边,而对受污染严重的港湾及河口的生物毒物研究得更多。  相似文献   

12.
对双台子河口潮滩上所采集沉积物样品的微量元素含量进行了测试分析,研究其空间分布特征、元素相关性以及元素组合特征,探索了微量元素在河口潮滩上的迁移富集规律及其控制因素。结果表明:潮滩沉积物中Cu、Pb、Zn元素富集,V元素流失;除Ti、Ba、Sr、Zr外,其余11种元素均表现为高潮滩比中低潮滩含量高;R型因子分析识别出3个微量元素组合,分别是Mn、Rb、Co、Cu等为代表的亲铁亲铜的元素组合,Sr、Ba等与含钾矿物有关的元素组合和Nb、Y等与细粒黏土有关的元素组合。  相似文献   

13.
A new voltammetric technique has been described for the determination of trace Cu, Pb, Cd and Zn in seawater by semidifferential electrochemical stripping analysis, in which the semiderivative, e, of the stripping current, i, is measured as a function of electrode potential, at a rotating thin mercury film glassy carbon electrode formed in situ. The optimun conditions are reported. It is demonstrated that the technique has more merits than that of the ordinary linear sweep anodic stripping voltammetry, greatly enhances the sensitivity and resolution and shortens the time of pre-electrolysis.  相似文献   

14.
We study the space-and-time variability of the concentrations of 27 microelements (Sc, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Mo, Ag, Cd, Sn, Se, Sb, Ba, La, Ce, Sm, Eu, Tb, Hf, Hg, Pb, Au, Th, and U) and Sr in the sea, river, and waste waters of the South Coast of Crimea in 2002–2007. Parallel with the data about elements studied earlier, we present, for the first time, the data of investigations of the contents of rareearth elements (Lu, Nd and Yb) whose concentrations in the major part of the analyzed samples of seawater were lower than the limit of their quantitative determination. We present the ranges of the concentrations of elements and perform their comparison with the data of the previous period of monitoring.  相似文献   

15.
The break-point in the Cu(II) titration curve obtained by anodic stripping voltammetry (ASV) is usually attributed to the formation of strong organo-copper complexes. This interpretation is the basis for the direct determination by ASV of the copper complexing capacity of natural waters. The present study suggests, however, that the break in the Cu(II) titration curve in seawater, as determined by ASV, could be due to the formation of a ZnCu intermetallic compound (IC) formed in the mercury during the deposition stage of the ASV procedure.  相似文献   

16.
To discuss the geochemical and environmental behavior of heavy metals in the Seto Inland Sea, the largest semi-enclosed coastal sea in Japan, mass balances of Cu and Zn were studied by application of a simple box model using sedimentation rates and heavy metal contents of core sediments. In 1980, total sedimentary loads of Cu and Zn over the whole area of the Sea were estimated to be 630 and 3500 tons year−1, respectively. Further, the sedimentary loads without (natural) and with human activities were estimated separately to be, respectively, 320 and 310 tons year−1 for Cu and 1800 and 1700 tons year−1 for Zn. Total inputs of Cu and Zn into the Sea, in 1980 were estimated to be 870 and 4250 tons year−1 about one half of this being the result of human activities. 70% of the Cu input and 80% of the Zn input are taken into the sediments. Mean residence times of Cu and Zn in the Sea are calculated to be ≈0.3 and 0.2 years, respectively. Since these values are relatively small compared to the mean residence time of the seawater (0.9 years), Cu and Zn supplied to the Sea are considered to be accumulated rapidly in the sediments.  相似文献   

17.
Isotope dilution mass spectrometry (IDMS) and ultra-clean room approach are successfully used in the determination of Cd, Pb and Zn in seawater and the sample pretreatment of analysis. The precision in the determination of Cd, Pb and Zn in seawater is better than±3% and the limits of detection are 6×10-12, 6×10-11 and 2.4×10-10 respectively. The effects of sample pretreatment such as filtration and acidification on the results of determination of Cd- Pb and Zn in seawater are disscussed.  相似文献   

18.
Introduction Hailing Bay located in western Guangdong province is an important marine aquaculture base and a famous scenic spot. Moyang River which flows across Yangjiang is the major runoff and polluted source in the sea area of Hailing Bay. Hailing Bank ( approximately 5 000 m ) which was built to connect Hailing Island and the continent in 1964 has blocked the natural circulation of suspended sand and pollutants in seawater. Water flux through the Yangjiang harbor extensively decreases …  相似文献   

19.
为了解昌黎黄金海岸保护区表层海域沉积物中重金属的污染状况,采用欧共体标准物质局(Community Bureau of Reference,简称BCR)提出的三级4步提取法分析了沉积物中Cr、Pb、Cu、Zn、Ni的形态特征,并利用次生相原生相分布比值法(Ratio of secondary phrase and pr...  相似文献   

20.
A column concentration-high resolution inductively coupled plasma mass spectrometry (ICP-MS) determination was applied to measure the total dissolved concentrations of Fe, Co, Ni, Cu and Zn in seawater collected from the subarctic North Pacific (~45°N) and the Bering Sea in July–September 1997. Total adsorbable Mn was determined on board by column electrolysis preconcentration and chemiluminescence detection. The vertical profiles for Fe, Ni and Zn were nutrient-like. The deep water concentration of Fe was ~0.5 nM in the northeast Pacific (18°-140°W) and increased to ~1 nM in the northwest Pacific (161°E) and ~2 nM in the Bering Sea (57°N, 180°E). The deep water concentrations for Ni and Zn in the Bering Sea were also 1.3–2 times higher than in the North Pacific. The profiles for Co and Cu were examined in the subarctic North Pacific, and results obtained were consistent with previous reports. There was a significant correlation between the concentrations of Co and Mn except for surface mixed layer. The profiles for total adsorbable Mn were similar to the reported profiles for total dissolvable Mn. The deep water concentration of Mn in the Bering Sea was also 4 times higher than in the North Pacific. Iron and zinc were depleted in surface water of the subarctic North Pacific. The relationship between these trace elements and nutrients suggests that these elements could be a limiting factor of phytoplankton productivity. In the Bering Sea, surface water contained ~0.3 nM of Fe. The Zn concentration, which was less than the detection limit in surface water, increased at shallower depths (~30 m) compared with the subarctic North Pacific. These results imply a higher flux of Fe and Zn to surface water in the Bering Sea. This in turn may cause the ecosystem in the Bering Sea characterized by a dominance of diatoms and high regenerated production.  相似文献   

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