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1.
通过改进Tessier连续提取法对贵州草海黑颈鹤栖息地不同水位梯度下沉积物汞(Hg)、砷(As)形态及生态风险进行了研究.结果表明,草海湿地沉积物中Hg含量在0.45~1.51-mg/kg之间,超过国家土壤环境质量农用地土壤风险管控标准;形态组成上,残渣态汞(Res-Hg)有机结合态汞(Org-Hg)碳酸盐结合态(Car-Hg)铁锰氧化态(Fe-O-Hg)可交换态(Ex-Hg),不同水位梯度下含量和赋存形态在不同区域不一致.As含量在16.4~23.8-mg/kg之间,形态依次为残渣态砷(Res-As)有机结合态砷(Org-As)铁锰氧化态砷(Fe-O-As)碳酸盐结合态砷(Car-As)可交换态砷(Ex-As).-As含量与贵州省土壤背景值持平,随着水位梯度的抬升,其总量呈增加趋势,残渣态占比逐步增多,性质逐渐稳定.采用地积累指数(I_(geo))、潜在生态风险指数(E_r~i)、风险评价编码法(RAC)对Hg、As的危害程度进行分析表明,基于草海较高Hg环境背景值,Hg整体污染风险较高,As处于低水平的污染风险等级且对环境影响较小.该研究揭示了不同水位梯度下Hg、As总量及形态分布特征,对草海湿地水位抬升恢复湿地提供了参考.  相似文献   
2.
石家庄污灌区土壤中As元素分布特征   总被引:2,自引:0,他引:2       下载免费PDF全文
根据石家庄污灌区土壤的平面和垂直剖面土壤样品中As含量数据,制作了As分布图,总结当地As元素分布特征。结果表明:石家庄污灌区内表层和深层土壤中As的分布都受到强烈的外源影响:表层As的分布受到污水排放源位置的控制,深层土壤也受纳了从上层向下迁移的外源As,在表层和深层都形成了若干高值区,各高值区具有独立成因;垂向分布上As主要富集在深部粘土层。  相似文献   
3.
ICP-MS测定土壤中的As、Cr、Pb、Se、Cu和Zn   总被引:1,自引:0,他引:1  
万飞  张之鑫 《吉林地质》2010,29(3):90-91,94
本文用电感耦合等离子质谱法(ICP-MS)测定了土壤的As、Cr、Pb、Se、Cu和Zn6种微量元素的质量分数,以In作为内标进行基体效应的补偿,方法快速灵敏,回收率为92.4%~106.8%,相对标准偏差小于5.0%,结果达到国家标准要求。  相似文献   
4.
采用微波消解对样品进行前处理,建立了氢化物发生-双道原子荧光光谱同时测定化肥中砷和汞的方法。以20 g/L KBH4为还原剂,8%的盐酸为载液,测定砷和汞的负高压均为270 V,砷的灯电流为60 mA,汞的灯电流为20 mA。讨论了常见元素对测定的干扰,40 g/L的主量元素N、P、K,10倍于砷、汞浓度的杂质元素Te、Ca、Zn、Cu、Cr、Mn、Ni、Sb、Sn、Pb对砷和汞测定的影响满足分析要求。方法测定砷和汞的线性范围As为0.68~100μg/L,Hg为0.12~10μg/L;检出限As为0.68μg/L,Hg为0.12μg/L;方法精密度(RSD,n=5)低于8%。该方法具有前处理简便快速、易于操作、灵敏度高等特点,能满足化肥中砷和汞同时测定的要求。  相似文献   
5.
武山铜矿北矿带ICu矿体砷的分布规律   总被引:1,自引:0,他引:1  
吴亚民 《矿产与地质》1999,13(5):283-288
武山铜矿化矿带ICu矿体是高砷矿体,分析了砷在各金属矿物中含量及分配情况和含砷量的分布规律,确定了高砷采场或矿段,指出了进行矿石质量控制,配矿管理的降砷途径。  相似文献   
6.
原子荧光光谱法直接连续测定化探样品中的As Sb Bi Hg   总被引:7,自引:1,他引:6  
研究了还原性介质中原子荧光光谱法直接连续测定化探样品中As、Sb、Bi、Hg的方法。按拟定的条件进行测定,各元素的检出限分别为As2.9×10-9、Sb1.3×10-10、Bi1.8×10-10、Hg5×10-11。应用于区域化探扫面工作中,效果良好。  相似文献   
7.
The Xiangxi Au–Sb–W deposit, the largest of its type in northwestern Hunan, China, is a sulfide-dominated ore body hosted by low grade metamorphic red slates of the Neoproterozoic Madiyi Formation. Three stages of mineralization, quartz–scheelite, quartz–gold–pyrite, quartz–gold–stibnite, and one metal-barren stage of veining, quartz–calcite, are recognized. Arsenopyrite occurs only as a minor mineral phase in the second stage. Analyses for 21 trace elements show that the enrichment factors of As in the metal deposit (EC [=element concentration of sample/average content of an element in the upper crust]: 190; 43 samples) in ore veins and in the Guanzhuang and Yuershan reference sections (3.7 km and 2.7 km away from the Xiangxi mine, EC: 3.5; 96 samples) are much smaller than those of Sb (52855 [in ore veins], 117 [in the sections]), W (5665, 7.5) and Au (2727, 5.3). The background concentrations of Au and As in the two sections were 1.4 ppb and 1.4 ppm, respectively. Arsenic (with an anomaly coefficient [AC = number of anomalous samples/total number of samples] of 76%) forms a larger geochemical halo than W (AC: 8%) and Au (AC: 32%). Gold and As in the deposit were transported mainly as metal complexes such as Au(HS)2, HnAs3S−(3−n)6 (n=1, 2 or 3) and HAsS02. Au(HS)2 is rapidly precipitated by a geochemical oxidation barrier — the red slates of the Madiyi Formation. As–S complexes in the stratigraphic horizon can be transformed into As–O complexes (e.g., H3AsO03) under oxidizing conditions, and are continuously transported. Therefore, they can be widely distributed in the red slate units, thus forming extensive geochemical haloes, so that As can be used as an indicator element for Au exploration in the Xiangxi region.  相似文献   
8.
Potential ecological risk of cadmium (Cd), lead (Pb) and arsenic (As) in agricultural black soil in Jilin Province, China was analyzed by the methods of risk assessment based on dose–effect relationships and ecological risk index. Heavy Cd-contamination occurred mainly around the coal mine region. The accumulation area for Pb appeared mostly in the suburbs and roadsides, whereas the higher As content was mainly found in the farmland of suburb and coal mine vicinity. In acute toxicity test, Cd, Pb and As in the soil had adverse effects on both roots and shoots growth in soybean with the greatest toxicity of arsenic and the least toxicity of lead at the same concentration levels. Exposed to Cd, Pb and As, the EC50 (50% effective concentration) values for the growth of soybean root (shoot) were 212.59 (376.70), 528.53 (828.69) and 194.60 (299.03) mg/kg, respectively. Results of potential ecological risk index showed that soil contamination from Cd in some samples had very high potential ecological risk; Pb contamination for almost all sampling sites had moderate ecological risk; while soil contamination from As had low ecological risk. With the present accumulation rate, concentrations of Cd, Pb and As in agricultural black soil near coal mine would reach the threshold values in 68, 175 and 120 years, respectively.  相似文献   
9.
10.
A method for the determination of Ge, As, Se and Te in silicate samples using isotope dilution-internal standardisation (ID-IS) octopole reaction cell (ORC) ICP-QMS by normal sample nebulisation was developed. The method does not involve either hydride generation or ion exchange. Germanium, Se and Te were determined by isotope dilution (ID), and As was determined by ID-IS. A silicate sample with an added Ge-Se-Te spike was digested with an HF-HNO3-HBr mixture, dried, re-dissolved with HF and the supernatant liquid was directly aspirated into an ORC-ICP-QMS instrument with He or H2 gas. No matrix effects were observed down to a dilution factor (DF) of ∼ 70 for Ge, Se and Te and DF of ∼ 1000 for As, which resulted in 3s detection limits in silicates of 2, 1, 0.1 and 4 ng g−1, respectively. Advantages of the method are the simple sample introduction as well as a capability of determining S, Ti, Zr, Nb, Mo, Sn, Sb, Hf and Ta by ID-IS-ICP-QMS/SFMS from the same solution. Furthermore, the total sample solution consumption was only 0.253 ml with DF = 2000. Therefore, only a 0.13 mg test portion was required. To demonstrate the applicability of this technique, Ge, As, Se and Te in eight silicate reference materials were determined, as well as S, Ti, Zr, Nb, Mo, Sn, Sb, Hf and Ta in four carbonaceous chondrites.  相似文献   
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