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1.
改进BCR法在活性污泥样品重金属形态分析中的应用   总被引:8,自引:0,他引:8  
利用改进的BCR三步顺序提取法研究了活性污泥中重金属的形态分布。所研究的可提取态包括可交换态,还原态-铁锰氧化物结合态和氧化态-有机物和硫化物结合态。这三态的含量之和加上残渣态的含量与各重金属的总量进行了比较。利用ICP-MS测定了活性污泥提取液以及残渣态中Cr,Mn,Co,Ni,Cu,Zn,As,Cd,Pb的含量。实验表明,采用改进的BCR法可以用来分析活性污泥样品中的金属形态。  相似文献   

2.
论文对丹-锡高速公路两旁土壤中重金属Pb、Cd、Cr、Cu、Zn、Fe、Ni和Mn元素的含量进行了采样调查。分别用单项污染指数、内梅罗指数和地累积指数对土壤中重金属元素的污染状况进行了评价。结果表明:高速公路两旁栽种防护林对土壤重金属污染起到一定的防护作用。随着距路基中心距离的增加,土壤pH值变化范围不大,土壤略呈弱酸性,土壤中Pb、Zn、Mn、Cd和Cu的含量呈现下降的趋势,Fe、Cr、Ni的含量在距路基10~30m范围内略有增加。公路两侧土壤中Pb含量超过背景值,但没有引起污染,Zn、Cr和Cd含量处于轻度到中度污染。土壤中Pb、Cd、Zn、Fe和Cu来自于同一类污染源。  相似文献   

3.
采用Tessier连续提取法对延安市污水处理厂污泥中的Zn、Cu、Cr、Cd、Pb和Mn六种重金属元素进行形态提取,并用电感耦合等离子体发射光谱(ICP-AES)法对其中各元素的总量及其形态进行测定。结果表明: Pb、Cd多以可交换态、碳酸盐结合态存在,分别占总量的76.84%和78.59%, 对生物具有潜在有效性。Zn、Cu、Cr多以稳定的硫化物及有机结合态和残渣态存在,不易迁移到环境中去。  相似文献   

4.
建立了微波消解-电感耦合等离子体质谱法,测定香菇、金针菇、白玉菇、杏鲍菇和茶树菇5种食用菌中必需微量元素(Mg、Ca、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Se、Sr)和有害元素(As、Cd、Pb)的含量。以微量元素为指标,评价5种食用菌的营养价值和食用安全性。结果表明,5种食用菌均含有丰富Mg、Ca、Cr、Mn、Fe、Cu、Zn,及少量V、Co、Ni、Se、Sr、As、Cd和Pb,且重金属As、Cd和Pb含量均低于国家标准(GB7096-2003)中关于食用菌规定的总量,食用安全。统计回归分析表明,香菇与其它4种食用菌同属真菌,因此微量元素含量相关系数R0.6,但P值均大于0.05,说明微量元素含量因科属的不同而有较大差异,但影响不显著。  相似文献   

5.
采用火焰原子吸收光谱法测定烟叶中Mn,Cu,Zn元素,石墨炉原子吸收光谱法测定Cd,Cr,Pb元素,以HNO3-H2O2微波消解法获取烟叶中的重金属总量,以超声水提取法获取水溶态重金属进行初级形态分析,以Tessier逐级提取法获取5种形态的重金属进行次级形态分析。实验结果表明,原子吸收光谱法检测6种重金属线性良好,相关系数(r2)不低于0.998 8,检出限为0.16~3.1μg·L-1。烟叶样品中Mn,Cu,Zn,Cd元素主要以可交换态和碳酸盐结合态的形式存在;Cr主要以残渣态的形式存在;而Pb主要以碳酸盐结合态和残渣态的形式存在。  相似文献   

6.
基于秦皇岛滨海湿地人工种植耐高盐碱蓬修复工程试验,通过分析湿地土壤沉积物及耐高盐碱蓬中不同金属元素的含量与变化,研究了耐高盐碱蓬对金属元素的富集特征。结果显示:湿地沉积物中Fe、Mn、Cr、Pb和Zn的浓度较高,分别为8 210. 94、110. 04、8. 78、8. 25、10. 95 mg/kg,Cd的浓度最低,平均值为0. 022 mg/kg,湿地试验区土壤中同一金属元素变异程度较小,分布较均匀。碱蓬体内重金属含量根据采集地点的不同有差异,但与各站位中土壤的重金属分布特征存在正相关性;其中碱蓬内Fe、Mn、Zn、Cu的平均含量相对较高,且Fe、Mn、Ni、Cu、As、Cd、Pb元素在碱蓬根中的平均含量高于茎叶,而Cr在茎中的平均含量最高,Zn和Mo在叶中的含量最高。碱蓬的根、茎、叶对Cd的富集效果最好,其次为Mo、Cu,对Fe、Mn、Zn、As和Pb的富集效果相对较差,说明碱蓬对沉积物中不同金属元素的富集移出率存在差异。金属元素在碱蓬中的转移系数研究表明,Mo、Zn、Cd和Mn等元素可由根部转移到叶中,而Fe、Ni、Pb、As和Cu等金属元素固定在根部,该研究可为利用碱蓬修复湿地重金属污染提供理论基础。  相似文献   

7.
以开封县污水处理厂污泥为实验材料,分析了污泥基本理化性质和Cu、Pb、Cr、As、Ni、Zn、Mn等元素的含量,利用BCR提取法研究其存在形态特征,并利用潜在生态危害指数法(RI),对污泥中重金属农用可能带来的潜在风险进行了综合性评价.结果表明,污泥的基本理化性质满足CJ/T309-2009农用泥质标准,污泥中所测元素含量均符合国家农用控制标准(GB 18918-2002),但Zn、Cu、Cr、As、Mn含量高于开封市潮土背景值.污泥中Mn主要以酸溶态和可还原态形式存在,Zn主要以可还原态形式存在,Ni在5种形态的分布差异不大,Cu、Pb主要以有机物结合态形式存在.单因子指数、内梅罗综合污染指数、地累积指数法对供试污泥样品的评价结果均为重污染水平,潜在生态危害指数48.92,属低风险水平.  相似文献   

8.
云当归与土壤中微量元素的测定及其相关性分析   总被引:1,自引:0,他引:1  
采用电感耦合等离子体原子发射光谱(ICP-AES)法对云当归以及土壤中11种微量元素进行了分析.结果显示,土壤中微量元素的含量依次为Zn>Cu>Pb>Fe>Mg>Mn>Ni>Cr> Cd> As> Hg;云当归中Mg、Fe、Mn、Zn中含量较高,而As、Cd、Cu、Pb、Hg等元素中含量相对较低,均低于药典标准.土壤中As与Cr、Pb与Zn存在极显著正相关(r=0.785,0.808);Mn与Cr存在极显著负相关(r=-0.733),As与Cu存在显著负相关(r=-0.631).云当归中Fe与Ni极显著正相关(r=0.731),Cd与Cu极显著负相关(r=-0.714);Zn与Hg显著相关(r=0.655),Ni与As、Fe与Pb、Fe与Cd显著负相关(r=-0.658,-0.637,-0.673).云当归与土壤中的As存在显著相关(r=0.707).  相似文献   

9.
利用改进的Tessier连续萃取法研究了伊通河长春市自由大桥处不同深度沉积物样品在氧化及还原条件下Cu,Pb,Zn和Ni的形态变化规律,同时分析了沉积物样品中酸可挥发性硫(Acid volatile sulfide,AVS)和同时提取重金属(Simultaneous extract metals,SEM)的含量. 实验结果表明,样品经干燥、研磨处理后,Cu有机/硫化物结合态比例减少40%,锰氧化物结合态的比例显著增加; Pb,Zn和Ni 3种元素有机/硫化物结合态比例均略有下降,变化幅度小于Cu,并重新分配到不同的化学相中. 通过SEM中各金属含量与有机/硫化物结合态中金属含量的对比可知,还原性沉积物中Cu除了与硫化物结合外,很大一部分是以有机物形态存在的,Pb,Zn,Ni,Fe和Mn则主要以硫化物形态存在,各元素形态分析均不同程度地受到萃取剂的影响.  相似文献   

10.
采用高分辨全谱直读电感耦合等离子体发射光谱仪测定了羊红膻(Pimpinella thellungianaWolff)药材地上与地下不同部位中含Cu、K、Na、Fe、Se、Mg、As、Ca、Cd、Cr、Mn、Ni、P、Pb和Zn等15种微量元素含量,并进行了比较。结果表明,重金属As和Pb几乎检测不到,K含量均高;同时也为羊红膻药理作用及临床用药提供科学依据。  相似文献   

11.
Concentrations of metals (Al, Fe, Ti, Ni, Mn, Cr, Zn, Cu, Pb) were determined in surface sediments from Taranto gulf (Ionian Sea, Southern Italy) in order to assess the distribution and the bioavailability of metals. Total metal content and speciation of Fe, Ni, Mn, Zn, Cu and Pb were determined. Sediment cores were also sampled in some stations of particular interest. The analytical results show that metals distribution does not show significant variations in relation to depth. Metal distribution in the Taranto gulf is mainly influenced by industrial wastes from Taranto town, by rivers of the Basilicata region and by prevailing anticlockwise marine currents. These factors cause an accumulation of metals in the sediments near to the coasts of Calabria. The statistical analysis, effected by HCA and PCA methods, can be considered a good starting point in order to classify sediment samples and to locate accumulation areas. Metal speciation shows that Fe, Ni and Zn are present in sediments mainly as sulphides, Mn is present principally in an ion-exchange form or bound to carbonate, while Cu and Pb are mainly present in the fraction bounds to humic acids.  相似文献   

12.
The state of heavy metal (Cd, Cu, Ni, Zn, Pb, and Cr) pollution was studied, in 440 texturally different soil profiles in Thessaly, an intensely cultivated region in Central Greece. The study was carried out in 2004 and 2005 on 220 soil samples for each year. Soil samples were classified in three soil orders: Endisols, Alfisols, and Vertisols according to the Soil Taxonomy System. The pseudo-total concentrations of heavy metals were determined by the aqua regia procedure. Heavy metals were also determined after division into four fractions by sequential extraction with (a) acetic acid (exchangeable and specifically adsorbed metals), (b) a reducing agent (bound to Fe/Mn hydroxides), (c) an oxidizing agent (bound to soil organic matter), and (d) aqua regia (bound to mineral structures, residual). The concentrations of all the metals studied were higher in the topsoil (0–30?cm) and lower in the second soil layer (30–60?cm). Concentrations of 70–82% of Cd, 39–64% of Cu, 41–69% of Ni, 29–51% of Zn, 75–89% of Pb, and 52–87% of Cr were found in the first two fractions. Cd appeared to be the most mobile of the metals studied, while Cu and Zn were found in forms associated with soil organic matter. The chemical partitioning patterns of Pb and Cr indicated that these metals are largely associated with the Fe–Mn hydroxides, while Cr was also found in the residual fractions. Significant correlations between heavy metals fractions and soil physicochemical parameters were obtained and discussed.  相似文献   

13.
The energy-dispersive X-ray fluorescence (EDXRF) spectroscopy has been used for the determination of essential and trace elements" contents of some twenty Nigerian medicinal plants. The accuracy and precision of the technique were assured by analyzing the European Community Bureau Reference Standard BCR 62 (Olive Leaves). Fourteen elements, namely K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb, Sr were detected with toxic heavy metal such as Cd, As, Pb, Hg were detected in the samples. The ranges of elemental concentrations varied from 7.7.104 to 1.6 mg/kg in the herbs. The results show that many of these plants contain elements of vital importance for human metabolism and prevention and healing of diseases.  相似文献   

14.
为研究黔产市售绿茶中重金属的含量分布特征及健康风险,以五个生产加工地的黔产市售绿茶为研究对象,分析其9种重金属(Pb、Cr、Cd、Hg、Cu、Zn、Mn、Ni和As)含量,利用美国环境保护署(USEPA)推荐的健康风险评价模型进行人体重金属的健康风险评价。结果表明,五种茶叶中Cr、Cd、Pb、Hg、Cu和As含量均低于国家限量标准。黔产市售绿茶的重金属浸出率大小次序为Zn>Mn>Hg>As>Cd>Pb>Cr>Cu>Ni。健康风险评价结果表明,五个产地的绿茶中重金属通过饮茶途径所产生的健康危害个人年风险大小次序为Cd>As>Mn>Ni>Cr>Hg>Pb>Zn>Cu,茶叶中重金属通过饮茶途径所产生的个人健康危害年风险总和为4.33×10-6~5.73×10-6 a-1,均低于USEPA和ICRP推荐的最大可接受风险水平,表明重金属引起的健康危害极小,其对暴露人群造成的健康危害可忽略不计,绿茶中重金属均处于安全范围内。  相似文献   

15.
The work presents an investigation on metal availability in sediments during 13 months using the dispersive-energy X-ray fluorescence (EDXRF) and atomic emission spectrometry with induced argon plasma (ICP-OES) techniques and single extraction (0.1 mol l−1 HCl) and Tessie’s sequential speciation methods. The EDXRF technique could yield essentially the same profile as ICP-OES for the seasonal variation of metals in sediments, but in a more practical way. The sequential extraction procedure (SEP) was more efficient in metal dissolution than single extraction. The Pb, Ni, Al, Cr, and Fe elements were less efficiently extracted with single extraction in relation to sequential extraction. For Co both methodologies were equivalent, but for Cu and Mn the extraction was higher with single extraction. Single extraction does not mobilize Pb, Ni, Al, Cr, and Fe adsorbed on oxides and bound to organic matter. However for Cu and Mn, not only extracted these metals from the four fractions, but it also dissolved part of the fifth fraction (residual). Principal Component Analysis discriminated seasonal variations in the content of several metals, mainly Fe, Co, Ni, and Zn. The mobility of metallic ions in the sediments is conditioned to the seasonal flow of organic and inorganic material coming from the river or by the erosion of adjacent soils.  相似文献   

16.
Abstract

This paper reports the distribution of a series of metals in natural samples collected at Carezza Lake in Antarctica, during the Italian Expedition in the austral summer 1989/90. The considered elements are: water, sediments and soil sampled from the surroundings of the lake and algae. The determination of the total concentration of the following metals was performed: Al, As, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Na, Ni, Pb, Zn. In addition, for sediment and soil samples, a speciation study was performed for some metals, namely Cd, Co, Cr, Cu, Fe, Mn, Ni, Zn, using the Tessier procedure.  相似文献   

17.
The objective of this research was to determine the differences between farmed and wild rainbow trout in terms of heavy metal and trace element accumulation in edible tissues. The samples were analyzed for As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se, Sr and Zn by inductively coupled plasma-optical emission spectrometry (ICP-OES); and for Hg by cold vapor atomic absorption spectrometry (CVAAS). The results were expressed as μg/g of dry weight. With the exception of Ba and Sr, liver had significantly higher heavy metal and trace element concentrations compared to the muscle in farmed or wild fish. Higher levels of Ba, Cr, Fe, Mn and Zn, as well as lower levels of Cu and Sr were found in tissues of wild rainbow trout compared to its farmed relative. Levels of Cd in 41.6% of farmed fish samples and 45.8% of wild fish samples exceeded the European Commission regulation. Regarding the Pb, concentrations in 50% of farmed fish samples and 62.5% of wild ones were above the European Commission limit. However, levels of Hg and As in all of the examined samples were lower than the legislated limits. The differences in heavy metal and trace element accumulation observed between farmed and wild fish were probably related to the differences in their environmental conditions and dietary element concentrations.  相似文献   

18.
Elements found in the edible parts of plants are considered to be the main source of nutrients for humans and animals. However, there is insufficient information on the relationship between heavy metal pollution in the growing soil of most edible plants. In this study, the distribution of elements in the edible forest nettle (Laportea alatipes) was evaluated as a function of geographical location. Forest land soils had higher concentrations of minor elements (Cu, Cr, Ni, and Zn) compared to soils from rural and suburban areas. Translocation factors for Cd and Pb showed effective translocation from the roots to the leaves; however, these heavy metals in leaves were still above South African maximum permissible levels for vegetables. Atmospheric depositions may play a significant role in higher Cd and Pb concentrations in the leaves. Bioaccumulation factors showed the plant to accumulate Cu, Mn, and Zn to meet physiological requirement levels. Geoaccumulation indices and enrichment factors showed no soil contamination or minimal enrichment by trace metals. Principal component analysis showed Co, Cr, Cu, Fe, Ni, Pb, and Zn in soil to originate from a common source which may be soil silicates and other minerals.  相似文献   

19.
以象山港海底沉积物为研究对象,采用了五步连续萃取法对象山港区域表层沉积物中重金属(Fe、Mn、Cu、Zn)赋存形态进行了研究,分析了各形态重金属在象山港不同采样点中的分布特征和影响因素.结果表明,象山港海域表层沉积物中各重金属元素主要来源于自然输入的残留态,人为输入的各种活性形态所占比例相对较少,但受两种因素的影响的差...  相似文献   

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