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41.
仪征市荧光灯厂周围环境中汞污染调查   总被引:3,自引:0,他引:3  
仪征市荧光灯厂排出的汞,对周围环境中的土壤、植物产生了明显污染,尤以土壤耕作层、植物叶片污染最明显。  相似文献   
42.
Monthly variability of Cd, Hg, Zn, Mn and Al concentrations in mussels (Mytilus californianus) soft tissue and brown seaweed (Macrocystis pyrifera) was studied at a pristine rocky shore off San Quintin Bay, Baja California, México. The results were related to climatic and hydrographic conditions and to the physiological state of the mussels (condition index) by correlation analysis and principal component analysis (PCA). A "normalization" to account for the variability induced by the physiological state of the mussel was performed. The PCA was performed in two ways to relate the environmental variables and the condition index to: (1) the metal concentrations in mussels, and (2) the "normalized" mussel concentrations. The association of the variability of Cd with the upwelling season was revealed in both PCAs. The temporal variability of this metal in mussels was highly correlated to that in seaweed, suggesting that the dissolved phase determined the variability of Cd in mussels. However, for Hg, Zn, Mn and Al the results from both PCAs were different. The first PCA showed the relationship of these metals to pluvial precipitation and to the condition index. The PCA for the normalized mussel concentrations showed that, after eliminating the effect of the condition index, only Al was related to pluvial precipitation. Manganese, and to a less degree Zn, were related to these metals in seaweed. Because zinc is an essential element in mussels, some regulation of their internal concentrations is likely. Mercury was not detected in seaweed, but because of its reactive nature, it is not expected that the dissolved fraction could be a significant pathway; therefore, it can be concluded that its temporal variability was determined by the variability in the condition index only.  相似文献   
43.
上海典型燃烧源铅和汞大气排放趋势分析   总被引:2,自引:1,他引:1  
杨静  陈龙  刘敏  孟祥周  张希 《环境科学》2018,39(9):3987-3994
上海百年来快速的城市化进程导致资源能源的大量消耗,并向城市环境中排放了大量有毒有害污染物.为探寻上海典型燃烧源重金属大气排放历史及趋势,基于上海化石燃料(煤炭和汽油)的历史消耗量及其大气铅(Pb)和汞(Hg)的排放因子,估算了上海主要燃煤部门(燃煤电厂、工业部门和居民生活)和机动车燃油大气Pb和Hg的历史排放量.结果表明,1949~2015年间大气Pb和Hg的燃煤排放量随时间推进均呈现先增长后下降趋势,即1949年解放后快速增长的煤炭消耗和较少的烟尘控制措施使其排放量出现急剧地波动式增长,至20世纪80~90年达到高峰,此后上海采取了各种减排和控制措施,使得目前三大燃煤源的大气Pb和Hg排放量出现大幅度下降.1980~2015年间上海大气Hg的燃煤排放比例一直占据主导地位(87.5%~99.7%).含铅汽油自1997年完全退出上海市场之后,燃煤排放替代其成为大气Pb的主要贡献源(78.2%~83.5%),然而自2005年起随着汽油消耗的急速增长,汽油燃烧排放又成为其主要贡献源(55.5%~79.1%).  相似文献   
44.
Mercury(Hg) is a neurotoxic metal which can enter into the human organism mainly by fish consumption, skin and transpiration. In the coastal zone of the southern Baltic Sea, rivers are the main source of Hg. The Polish region represents the largest proportion of the Baltic Sea catchment and this research included four rivers of the Baltic watershed: the Reda,Zagórska Struga, Kacza and Gizdepka. The samples were collected in the years 2011–2013.Total and particulate Hg concentration in these rivers were measured. Due to intensive rain,deposited mercury on the catchment area was washed out into the riverines water and introduced into the Baltic Sea. Consequently, the load of Hg increased three times.Additionally, the intensive dry atmospheric deposition during heating season caused the increase of the concentration of particulate Hg in the river water even by 85%. The research confirmed the role of the river flow magnitude in the load of mercury introduced into the sea by rivers. Moreover, a high variability of mercury concentration was connected to the additional sources such as the chemicals containing Hg and no municipal sewage system.The analysis of stable isotopes indicated that the SPM contained terrestrial organic matter;however, there was no clear correlation between Hgtot, Corgand Ntotconcentrations and δ~(13)C, δ~(15)N, C/N in particulate matter.  相似文献   
45.
Wet deposition is an important source of metals to the sea. The temporal variability of Hg concentrations in precipitation, and the impact of air masses of different origins over the Polish coastal zone were assessed. Samples of precipitation were collected (August 2008–May 2009) at an urbanized coastal station in Poland. Hg analyses were conducted using CVAFS. These were the first measurements of Hg concentration in precipitation obtained in the Polish coastal zone. Since Poland was identified as the biggest emitter of Hg to the Baltic, these data are very important. In the heating and non-heating season, Hg concentrations in precipitation were similar. Hg wet deposition flux dominated in summer, when the production of biomass in the aquatic system was able to actively adsorb Hg. Input of metal to the sea was attributed to regional and distant sources. Maritime air masses, through transformation of Hg(0), were an essential vector of mercury in precipitation.  相似文献   
46.
我国14种典型土壤脲酶、脱氢酶活性对汞胁迫的响应   总被引:5,自引:0,他引:5  
Hg作为环境的主要污染重金属之一,其对土壤酶的影响是表征其环境效应的重要方面,结果可为土壤环境监测等提供生物学依据.因此,本文通过室内模拟试验,较系统地分析了全国14种主要类型18个土样的脲酶和脱氢酶活性在Hg胁迫下的响应.结果表明,Hg会抑制土壤酶活性,其降幅随土壤类型的不同有明显差异;随着Hg含量的升高,土壤脲酶和脱氢酶活性均显著降低;模型U=A/(1+B×C)可较好地拟合酶活性(U)与汞含量(C)之间的关系,揭示出土壤脲酶和脱氢酶在一定程度上可监测土壤Hg污染的程度,且机理为完全抑制(包括竞争性抑制和非竞争性抑制)作用.同时,实验获得的供试土样脲酶的生态剂量(ED10)范围为0.08~0.77 mg·kg-1,脱氢酶ED10范围为0.11~2.58mg·kg-1,从土壤酶角度获得的土壤汞轻度污染临界值为0.08 mg·kg-1,此值要小于国家土壤质量标准中的二级标准.有机质、pH、CEC和粘粒显著影响了汞与土壤脱氢酶的关系,上述4个土壤性状参数值越高,汞对土壤酶的毒害作用就越弱;酸性土壤中汞的毒害作用强于碱性土壤.表明在我国主要土壤类型上,土壤脲酶、脱氢酶对Hg毒性均较为敏感,可在更广范围内作为Hg污染程度的监测指标之一.  相似文献   
47.
从溧  王媛 《四川环境》1994,13(1):26-29
本文介绍了在环境监测中,经试验研究,确定的用阳极溶出伏安法,连续分析环境样品中重金属Cu,Pb,Cd的最佳条件,即用悬汞电极做工作电极,用0.1M离氯酸做支持电解质,纯氮除氧。当PH值取2-7,富集电位数-1.1~-1.2V时,不但可连续测定一定浓度范围的重金属Cd,Pb,CU;而且方法灵敏度高,精密良好,线性相关关系可达0.9990,回收率达85-115%,获得了良好的分析效果。  相似文献   
48.
我国已加入WTO,国际间的合作日益加强。环境监测部门不仅要了解本国本行业的规范,还应了解世界,了解国外的标准分析方法。对中国和美国的4种冷原子吸收分光光度法测定汞作了比较;提出用冷原子吸收分光光度法测定汞时,应按照不同的样品及不同的要求,选择合适的方法以实现质量控制的要求。  相似文献   
49.
Cyprinus carpio were exposed to two non-essential (Hg and Pb)and two essential (Cu and Ni) heavy metal salts at lethal andsub-lethal concentrations. Blood serum total protein, serum globulinand serum albumin was analysed every 2 hr for 24 hrs andagain at 48 and 72 hrs. Serum protein and globulin level showedan intial sharp increase from 2 to 20 hrs, followed by decline thatextend over a period of 72 hrs. Serum albumin showed an initialimmediate decline from 2 to 4 hrs, followed by an intermittent period of recovery and decline that extend over a period of 72hrs. Both lethal and sub-lethal concentrations of metal salts elicited asimilar pattern of response varying only in magnitude. The use offish blood serum protein, albumin and globulin measurements as general indicators of pollutant stress response isdiscussed.  相似文献   
50.
氢化物原子荧光法同时测定海洋沉积物中的痕量 As和Hg   总被引:1,自引:1,他引:0  
尝试一次消解海洋沉积物样品,用氢化物原子荧光法同时测定As和Hg。试验了KBH4的浓度、共存离子的影响,优化了仪器条件。方法回收率分别为:As为91.9%~105%、Hg为93.0%~109%,As、Hg的线性范围、检出限分别为0~8μg.L-1和0~800 ng.L-1、0.06μg.L-1和2.65 ng.L-1、RSD为4.7%和5.8%。方法具有操作简单、快速、灵敏度高等优点。  相似文献   
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