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401.
宁波台ZK03井气氡仪在2017年12月更新为BG2015测氡仪,2018年12月又增上ATG6138M痕量汞仪,两套仪器采用同一脱气装置,记录显示采用原系统气氡仪、气汞仪数据离散度大,分析原因是一方面该井流量逐年降低使原脱气装置显现弊端,由于设计缺陷集气室进水量小造成原出水口不能实现水封空气出现跑气现象;另一方面ATG6138M痕量汞仪设计有定时吸气功能,原装置液面与脱气口间距小,部分水汽吸入仪器,引起仪器工作不稳定。为此,该台进行针对性设计改造,监测数据显示此次改造解决了原脱气装置缺陷,取得良好的效果。  相似文献   
402.
The study was to find out the effect of cadmium and mercury on levels of hemolymph glucose, crustacean hyperglycemic hormone (CHH) and hepatopancreas glycogen in the blue swimmer crab Portunus pelagicus. The experiments were performed in both intact and eyestalk ablated crabs. Quantification of CHH was done by the indirect ELISA with the aid of primary anti-Carcinus maenas-CHH antibody. Higher glucose concentration was observed on exposure to 8×10-6 of cadmium ((825.6±5.42) μg/mL) and 6×10-6 of mercury ((90.5±6.25) μg/mL) after 48 h and 24 h respectively. Higher level of hemolymph glucose was observed in eyestalk intact crabs on exposure to cadmium and mercury than eyestalk ablated crabs. Decrease in the levels of CHH was observed in both eyestalk intact and ablated crabs on heavy metal exposure. Decline of the hepatopancreas glycogen level was also witnessed with the exposure to heavy metal, which validated its utilization in the production of glucose. Thus this study brings to light, the variations in hemolymph glucose, CHH and hepatopancreas glycogen on heavy metal stress. These carbohydrate metabolites can be used as biomarkers in assessing heavy metal contamination in water bodies.  相似文献   
403.
Gao  Xing  Kang  Shichang  Liu  Qingsong  Chen  Pengfei  Duan  Zongqi 《地理学报(英文版)》2020,30(9):1481-1494
Heavy metals,one of the most toxic classes of pollutants,are resistant to degradation and harmful to the biological environment.The lakes that have developed on the Tibetan Plateau are ideal regions to investigate historic heavy metal pollution,particularly through the use of the reliable 210 Pb dating technique.Environmental magnetism has been successfully applied to estimate heavy metal pollution in different environmental systems due to its characteristics of simple processing steps,good sensitivity,and non-destructibility.However,it has not yet been applied to assess heavy metal pollution in lake sediments on the Tibetan Plateau.A series of environmental magnetic investigations of Qiangyong Co Lake sediments(southern Tibetan Plateau) was therefore conducted to explore the relationship between magnetic minerals and mercury(Hg) concentrations.The results showed that the magnetic mineral species in lake sediments remained stable,with similar levels of four different components from 1899 to 2011.However,the proportion of component 1(C1,hematite) increased continuously with the corresponding decrease in the proportion of C2(goethite),while the proportions of C3 and C4(magnetite) did not change significantly.As a result,the bulk magnetic signals(e.g.,SIRM and clf) were unsuitable for the evaluation of the Hg concentration;however,the proportion of hematite had a strong positive correlation with the Hg concentration.It is possible that the Qiangyong Glacier(the main water supply for Qiangyong Co Lake) has experienced faster melting with global and local warming,and the Hg trapped in cryoconite and ice was released.Hematite,with a large specific surface area,has a strong capacity for absorbing Hg,and both materials are ultimately transported to Qiangyong Co Lake.The proportion of hematite in a sample is therefore a suitable semi-quantitative proxy that can be used to evaluate the Hg concentration in Qiangyong Co Lake sediments.This study confirmed that the variation of magnetic minerals can provide a new method to estimate the variation of Hg concentrations and to study the process of Hg deposition in lakes in the southern Tibetan Plateau on the basis of a detailed environmental magnetic analysis.  相似文献   
404.
Mercury (Hg) is one of the commonly encountered heavy metals, which is widespread in inshore sediments of China. In order to investigate the toxicity of Hg on marine invertebrates, we studied the effects of the divalent mercuricion (Hg2+) (at two final concentrations of 0.0025 and 0.0050 mg L−1, prepared with HgCl2) on metallothionein (MT) content, DNA integrity (DNA strand breaks) and catalase (CAT) in the gills and hepatopancreas, antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), in the hemolymph, gills and hepatopancreas of the portunid crab Charybdis japonica for an experiment period up to 15 d. The results indicated that MT was significantly induced after 3 d, with a positive correlation with Hg2+ dose and time in the hepatopancreas and a negative correlation with Hg2+ dose and time in the gills. While CAT in the hemolymph was not detected, it increased in the hepatopancreas during the entire experiment; SOD and GPx in the three tissues were stimulated after 12 h, both attained peak value and then reduced during the experimental period. Meanwhile, DNA strand breaks were all induced significantly after 12 h. These results suggested the detoxification strategies against Hg2+ in three tissues of C. japonica.  相似文献   
405.
The Marano Lagoon, in the northern Adriatic Sea (Italy), has been affected by mercury (Hg) contamination from industrial and mining activities. It has been estimated that 186,000 kg of Hg were deliberately discharged into the main drainage system (Aussa–Corno River) by a chlor-alkali plant (CAP) from 1940s to 1984. The lagoon has also experienced a secondary long-term Hg input, originated from mining activity in Idrija (Slovenia), due to the supply of fluvial suspended particles carried by the Isonzo River in the Gulf of Trieste. Since local fishing activities are extensively conducted, there is great concern on the risk posed by potentially harmful effects of Hg to the trophic chain.  相似文献   
406.
Causes of variation in mobilization of mercury into Black-winged Stilt Himantopus himantopus chicks were studied through analysis of stable isotope ratios of carbon and nitrogen. Blood and breast feathers were collected from chicks in coastal saltpans during successive breeding seasons. Detritus samples and potential prey (macroinvertebrates) were also collected. Total mercury concentrations and stable isotope signatures were measured using atomic absorption spectroscopy and isotope ratio mass spectrometry respectively. Mercury levels in Chironomidae, Corixidae and Hydrophilidae correlated with mercury levels in chick feathers. Differences of δ15N signatures between macroinvertebrate groups indicated that they belong to different trophic levels. δ15N signatures of invertebrates correlated with mercury levels in invertebrates and chicks, but not with δ15N signatures in chicks. Between-group and between-site differences of δ15N signatures and mercury levels in invertebrates suggested that they contribute differently to mercury mobilization into chicks, and their relative contribution depends on prey availability in each site. Inter-site differences in the biomagnification factor reinforced that idea. δ13C signatures in invertebrates marked a larger range of carbon sources than just detritus. Variation of water inflow regime and prey availability may cause between-group and between-site differences of δ13C signatures in prey. Discrepancies between feather and blood for δ13C signatures in Praias-Sado and Vaia suggested that temporal variation of prey availability may be the main factor affecting mercury mobilization into chicks in both those cases, since their water inflow regimes are the same. The lowest levels of δ13C signatures in Vau suggested that water inflow regime may be the main factor in this case, since no discrepancy existed in δ13C signatures between blood and feather.  相似文献   
407.
对广西珊瑚钨锡矿周边尾砂厂、废石厂和居民区土壤、植被进行采样分析,采集珊瑚矿周边尾砂厂、废石厂和居民区采集土壤样271620个,尾砂厂采植物样27个。采用原子荧光测汞仪进行分析测定法,研究土壤和茅草的不同部分中的汞含量。分析表明,距离矿区近的土壤汞含量高于距离矿区远的;土壤汞含量居民区大于尾砂场大于废石场。其中有65.0%的居民区、7.4%的尾砂场和6.3%废石场的样汞含量超过了我国《土壤环境质量标准(GB 156182008)》第二级标准的最低限值(汞≤0.2μg/g)。  相似文献   
408.
李世铸 《地质与勘探》2015,51(6):1150-1158
本文通过对标准样品的重量和时间测试实验,在云南会泽县金红铅锌矿区已知剖面开展温度实验,找出土壤热释汞的最佳测试条件,从而排除影响该方法找矿预测的干扰因素,建立一套适合该区土壤热释汞找矿预测的标准方法。利用该方法实验结论,对该区土壤样品做了300℃和650℃两个温度的条件下的平面异常对比,结合该区地质背景分析验证300℃这个温度条件适合于该区土壤样品测试分析,并在此温度条件下对该区进行找矿预测评价。  相似文献   
409.
崔德松 《岩矿测试》2011,30(3):321-324
利用铜(Ⅱ)与铜试剂反应生成鳌合物沉淀的同时,能将痕量汞(Ⅱ)共同沉淀出来的特性,将汞(Ⅱ)分离富集,电感耦合等离子体发射光谱法测定地下水中汞的含量。在汞标准溶液中,加入不同量的铜和铜试剂测定汞的真实含量,最终确定铜和铜试剂最佳加入量。通过优选分析线、背景恰当扣除处理,水溶液体积由200 mL浓缩至5 mL,富集40倍后汞的检出限可达0.1μg/L。方法用于测定国家标准物质GBW(E)080006和实际样品,测定值与标准值、国家标准方法测定值一致,均在允许误差范围内。方法精密度(RSD,n=12)小于10%,可满足地下水中痕量汞的测定要求。  相似文献   
410.
Total mercury was analyzed as a function of body length, season, and diet in four commercially and recreationally important marine fish, bluefish (Pomatomus saltatrix), goosefish (Lophius americanus), silver hake (Merluccius bilinearis), and summer flounder (Paralichthys dentatus), collected from continental shelf waters of the northwest Atlantic Ocean. Mercury levels in the dorsal muscle tissue of 115 individuals ranged from 0.006 to 1.217 μg/g (wet weight) and varied significantly among species. The relationship between predator length and mercury concentration was linear for bluefish and summer flounder, while mercury levels increased with size at an exponential rate for silver hake and goosefish. Mercury burdens were the highest overall in bluefish, but increased with size at the greatest rate in silver hake. Seasonal differences were detected for bluefish and goosefish with mercury levels peaking during summer and spring, respectively. Prey mercury burdens and predator foraging habits are discussed as the primary factors influencing mercury accumulation.  相似文献   
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