西藏鄂雅错盐湖砷和汞的分布特征研究          下载免费PDF全文

陈嘉琪  王建萍  张耀玲  凌智永 《盐湖研究》2022,30(2):61-69

本研究对西藏鄂雅错盐湖和主要支流中不同形态的砷(亚砷酸盐As(Ⅲ)、砷酸盐As(Ⅴ)、一甲基砷酸MMA、二甲基砷酸DMA)和总汞(THg)含量进行了测定,并与主要水质参数进行相关性分析研究,结果表明鄂雅错盐湖As主要以As(Ⅴ)形态存在,其次分别为As(Ⅲ)、DMA和MMA,其中无机砷的含量明显大于有机砷。相比较其他砷的形态,盐湖中As(Ⅲ)与主要水质参数的相关性显著,与总溶解性固体(TDS)、总溶解态氮(DTN)呈显著的强正相关性,与水温、溶解氧 (DO)、氧化还原电位(Eh)、pH呈显著负相关性。总汞浓度较低,且与主要水质参数相关性不显著。通过风险评价发现鄂雅错湖水中砷存在一定的致癌健康风险,汞不存在风险。本研究丰富了西藏盐湖和支流水体中砷、汞分布特征及其环境影响因素的认识,对于环境保护具有一定的意义。  相似文献   

巯基棉富集分离—冷原子吸收法测定天然水中痕量汞     

范美容  黄懿 《河南国土资源》1999,(4)

用巯基棉富集水中痕量汞，用饱和氯化钠的盐酸溶液解吸，冷原子吸收法测定。当水样取１ Ｌ时，最低检测浓度可达０－００３ μｇ／Ｌ，方法相对标准偏差为３－８ ％ ～６－９ ％ ，巯基棉汞平均回收率为９１－１％ 。该法操作简单、快速、富集倍数大，适用于天然水中痕量汞的分析。  相似文献   

无色散原子荧光光谱法测定痕量汞     

王振福 《国土资源》1991,(2)

氯化亚锡还原冷蒸汽无色散原子荧光光谱法测定痕量汞,采用硫酸、双氧水、王水逐次加入低温分析样品,可以保证样品分解完全又可避免汞的损失。汞的检出限为6.0×10~(-10)g,精密度RSD％=4.1。该方法操作简便,快速、准确、费用低,可应用于大批量地球化学样品的分析。  相似文献   

The role of two sediment-dwelling invertebrates on the mercury transfer from sediments to the estuarine trophic web     

J.P. Coelho  M. Nunes  M. Dolbeth  M.E. Pereira  A.C. Duarte  M.A. Pardal 《Estuarine, Coastal and Shelf Science》2008

The annual total and organic mercury bioaccumulation pattern of Scrobicularia plana and Hediste diversicolor was assessed to evaluate the potential mercury transfer from contaminated sediments to estuarine food webs. S. plana was found to accumulate more total and organic mercury than H. diversicolor, up to 0.79 mg kg⁻¹ and 0.15 mg kg⁻¹ (wet weight) respectively, with a maximum annual uptake of 0.21 mg kg⁻¹ y⁻¹, while for methylmercury the annual accumulation was similar between species and never exceeded 0.045 mg kg⁻¹ y⁻¹. The higher organic mercury fraction in H. diversicolor is related to the omnivorous diet of this species. Both species increase methylmercury exposure by burrowing activities and uptake in anoxic, methylmercury rich sediment layers. Integration with the annual biological production of each species revealed mercury incorporation rates that reached 28 μg m⁻² y⁻¹, and to extract as much as 11.5 g Hg y⁻¹ (of which 95% associated with S. plana) in the 0.4 km² of the most contaminated area, that can be transferred to higher trophic levels. S. plana is therefore an essential vector in the mercury biomagnification processes, through uptake from contaminated sediments and, by predation, to transfer it to economically important and exploited estuarine species.  相似文献   

Enhanced concentrations of dissolved gaseous mercury in the surface waters of the Arctic Ocean   总被引：2，自引：0，他引：2  

M.E. Andersson  J. Sommar  K. Grdfeldt  O. Lindqvist 《Marine Chemistry》2008,110(3-4):190-194

During an almost three months long expedition in the Arctic Ocean, the Beringia 2005, dissolved gaseous mercury (DGM) was measured continuously in the surface water. The DGM concentration was measured using an equilibrium system, i.e. the DGM in the water phase equilibrated with a stream of gas and the gas was thereafter analysed with respect to its mercury content. The DGM concentrations were calculated using the following equation, DGM = Hg_eq / k_H' where Hg_eq is the equilibrated concentration of elemental mercury in the gas phase and k_H' is the dimensionless Henry's law constant at desired temperature and salinity. During the expedition several features were observed. For example, enhanced DGM concentration was measured underneath the ice which may indicate that the sea ice acted as a barrier for evasion of mercury from the Arctic Ocean to the atmosphere. Furthermore, elevated DGM concentrations were observed in water that might have originated from river discharge. The gas-exchange of mercury between the ocean and the atmosphere was calculated in the open water and both deposition and evasion were observed. The measurements showed significantly enhanced DGM concentrations, compared to more southern latitudes.  相似文献   

电感耦合等离子体质谱-原子荧光光谱法研究上海口岸进口印度尼西亚煤炭微量元素的赋存形态特征   总被引：1，自引：1，他引：0  

刘曙  沈劼  周海明  诸秀芬  朱志秀  李晨  兰超 《岩矿测试》2015,34(4):436-441

印度尼西亚是我国最大的煤炭进口国,本文应用电感耦合等离子体质谱、原子荧光光谱、直接测汞仪等技术分析了上海口岸31批进口印度尼西亚煤炭中的12种微量元素,结合数理统计方法研究该类煤炭中微量元素的赋存形态。结果表明,进口印尼煤炭中含有高汞煤、三级含砷煤,As、Hg的平均富集系数大于1,其迁移风险值得关注;Be、Cu、Mo、Cd、Sn、Pb含量均低于中国煤和世界煤炭的平均水平,体现出印尼煤炭低灰分的品质特征。12种微量元素和相关项目(灰分和全硫)可划分为3类:第一类归纳为黏土矿物吸附类,包括As、Be、Cr、Co、Ni、Cu、Mo、Cd、Sn、Pb、灰分;第二类归纳为硫铁矿类,包括Hg、全硫;第三类归纳为碳酸盐矿物类,包括Ba。本文研究结果对于指导进口煤炭开发、利用过程中的环境评价和洁净化处理具有一定的参考价值。  相似文献   

鄂尔多斯盆地子洲气田上古生界山西组、下石盒子组储集层特征对比研究   总被引：2，自引：0，他引：2       下载免费PDF全文

王若谷  李文厚  廖友运  冯永玖  郭艳琴  马瑶  许星 《地质科学》2015,50(1):249-261

鄂尔多斯盆地子洲气田山西组山2~3段和下石盒子组盒8段是该区天然气的主力储集层,但其产能却存在很大差异。应用薄片鉴定、扫描电镜、高压压汞、恒速压汞及岩心分析资料,分别对该地区上古生界山西组山2~3段和下石盒子组盒8段储集层进行了研究。子洲气田山2~3储层以石英砂岩为主,孔隙类型多样,粒间孔、溶孔、晶间孔发育,喉道类别以微—细喉为主,属相对低孔高渗型储层;盒8储层则以岩屑砂岩为主,孔隙类型主要为岩屑溶孔和晶间孔,喉道类别以细—微喉为主,属于相对低孔低渗型储层。山2~3段和盒8段储集层岩石类型、孔隙结构差别巨大,造成了其储集性能的差异性。不同的沉积环境和成岩作用是造成其差异性的主要原因。  相似文献   

贵州施秉白云岩溶蚀特性及孔隙特征实验研究   总被引：3，自引：0，他引：3  

刘琦  顾展飞  卢耀如  刘之葵 《地球学报》2015,36(4):413-418

以贵州施秉白云岩为研究对象,从宏观和微观角度分析白云岩的溶蚀特性及孔隙特征,结果显示:(1)在众多影响施秉喀斯特发育的因素中,矿物成分是最基本的内因,水是最关键的外因,孔隙结构起辅助作用。(2)极细晶白云岩的单位表面积溶蚀量一般大于细晶白云岩的,在晶粒相同的情况下,白云岩的溶蚀量与Ca O和Mg O的含量分别成正比,且Mg O的含量影响较Ca O大。(3)施秉白云岩溶蚀速率不仅受岩石矿物颗粒粒径大小的控制,还受岩石内部孔隙结构特征的影响,颗粒粒径越大,孔隙度越高,连通性越好,越有利于水溶液进入,溶蚀量也就越大。(4)施秉白云岩的溶蚀特性是多种因素综合作用的结果,必须把各个因素分离开来,从宏观和微观角度逐个作详细的分析研究,然后综合起来,才能对喀斯特发育规律有更深入的了解。  相似文献   

卧龙湖煤矿岩浆蚀变煤层中汞的分布与赋存特征          下载免费PDF全文

黄晓雨  郑刘根  张强伟  储浩  储欢  闫笑笑  韩园园 《高校地质学报》2015,21(2):280

系统采集淮北卧龙湖煤矿岩浆蚀变煤层中岩浆岩、煤及顶底板岩石样品,测试分析了样品中汞、灰分、挥发分、水 分以及各形态硫的含量,探讨了岩浆蚀变煤层中汞的分布与赋存特征。结果表明：（1） 岩浆侵入导致煤中灰分升高,挥发 分降低,煤中硫主要以黄铁矿硫和有机硫存在;（2） 岩浆侵入导致煤中汞的富集,卧龙湖煤矿岩浆蚀变煤层中汞的平均含 量高达0.23×10-6,是华北石炭-二叠纪煤、中国煤以及美国煤中汞的平均含量的1.4 倍,1.2 倍和1.3 倍;（3） 煤中汞的含量 随离岩浆侵入体距离增大有逐渐降低的趋势,但在煤岩接触带附近,汞在岩浆侵入体上方和下方的煤中呈现不同的分布特 征;（4） 煤中的汞主要以无机结合态的形式存在,且大部分赋存在煤中的黄铁矿中,同时亦存在与有机硫结合的汞。岩浆 热液对煤层的侵入,导致煤质以及煤中汞的含量和赋存方式发生了显著变化。  相似文献   

Mired in the past — looking to the future: Geochemistry of peat and the analysis of past environmental changes     

Richard Bindler   《Global and Planetary Change》2006,53(4):209

Peat cores from ombrotrophic bogs have been used as a valuable archive to study environmental change for over a century. Much of this focus on the peat record has been on biological proxies of environmental change, such as pollen and peat-forming macrofossils, but there is growing interest in the geochemical record to study environmental changes. Several studies of long-term peat records in Europe have reconstructed past changes in atmospheric lead pollution, for example, and the general cohesiveness of the results and their agreement with known historical trends in metal production exemplify the best potential of peat geochemistry as an environmental archive. Based on the success with lead, a current emphasis in peat reconstructions is to assess the record of past mercury deposition and results thus far show generally consistent trends, e.g., a pre-anthropogenic mercury accumulation rate of about 0.5–1.5 μg Hg m^− 2 year^− 1. Despite this general consistency there is increasing concern that there may be diagenetic effects on the quantitative record of some metals, which can be inferred based on a strong relationship between mercury and other organically bound elements and proxies for peat decomposition (C/N ratio). However, it is possible that changes in decomposition and the alteration of some metal records could provide climatic information. A few recent studies show that closer examination of the geochemical matrix, in some cases along with biological proxies, can provide valuable information on landscape changes and climate; for example, partitioning metals into different weight fractions and source regions can be applied to climate studies. The best interpretations of the peat geochemical record in the context of environmental and climate change will likely come when geochemical and biological records are considered simultaneously.  相似文献