Atmospheric Mercury Concentrations from Several Observatory Sites in the Northern Hemisphere   总被引：4，自引：0，他引：4  

Ki-Hyun?KimEmail author  R.?Ebinghaus  W.?H.?Schroeder  P.?Blanchard  H.?H.?Kock  A.?Steffen  F.?A.?Froude  Min-Young?Kim  Sungmin?Hong  Jae-Hwan?Kim 《Journal of Atmospheric Chemistry》2005,50(1):1-24

In an effort to investigate both large-scale (spatial) and short/long-term (temporal) distribution characteristics of atmospheric mercury, we have combined and analyzed the Hg concentration data sets collected continuously by four different scientific groups for the areas and periods covering (1) America (three sites near the Canadian Great Lakes (CGL): 1997–2000), (2) Asia (Seoul, Korea (SEL): 1997–2002), (3) Arctic (Alert, Canada (ALT): 1995–2001), and (4) Europe (Mace Head, Ireland (MH): 1996–2002). The mean concentrations of Hg data from those widely dispersed monitoring stations were computed to be (1) 1.58 ± 0.23, 1.69 ± 0.32, and 1.93 ± 0.44 (three sites in CGL), (2) 5.06 ± 2.46 ng m^–3 (SEL), (3) 1.55 ± 0.41 (ALT), and (4) 1.76 ± 0.31 (MH). Intersite relationships were investigated among all different stations using the data groups divided into different temporal intervals. The analysis of diurnal variation patterns of Hg indicated differences in regional source/sink characteristics, with increasing amplitudes of variability toward areas under the strong influence of anthropogenic sources. When the analysis was made over different seasons, the patterns contrasted greatly between the Arctic and the other areas. It was found that the relative enhancement of Hg concentrations was dominant during winter/spring in most areas due to direct or indirect influences of anthropogenic emissions. However, the pattern for the Arctic area was distinguished pronouncedly from others with the spring minimum and summer maximum both of which reflect the potent effects of mercury depletion phenomenon (MDP). By contrast, no long-term trend, either being an increase or decrease, was evident from any of the stations during each respective study period. Although our initial attempts to examine the distribution characteristics of Hg analyzed by different scientific groups were successful, we feel that these efforts should be continued further to extend the compatibility of the global database of Hg.  相似文献   

汞等重金属元素在黄浦江中迁移富集研究   总被引：1，自引：0，他引：1       下载免费PDF全文

程金平  刘彩娥  王文华 《水科学进展》2005,16(6):767-772

为了探讨生物膜对重金属元素的富集,以及生物膜在水-沉积物交换过程中的影响和贡献,研究了生物膜和沉积物对于汞等重金属的吸附以及吸附前后汞形态的变化.结果表明沉积物中的汞和大部分重金属元素以残渣态为主,可交换态、有机质结合态、碳酸盐结合态百分含量相对较少.生物膜中有机质含量很高,生长时间,光照,季节都是影响生物膜中重金属元素含量的重要因素.可以推断,光照越强,温度越高,生长时间越长,生物膜中重金属元素含量越高.  相似文献   

pH 值对包气带土壤吸附铅和汞的影响实验   总被引：5，自引：0，他引：5  

赵金艳  王金生  孙福丽  滕彦国  葛晓立 《水文地质工程地质》2005,32(6):16-19

本文测定了北京西郊4组不同包气带土壤中铅和汞的含量,探讨了pH值变化对铅和汞在土壤样品中分配系数的影响。结果表明:随着pH值的升高,汞和铅在土壤中的分配系数逐步增大,随后降低,pH值与分配系数关系曲线为单峰曲线。汞在砂壤土、轻壤土和中壤土中的分配系数Kd值在0~160mL/g之间,当pH值为10左右时,Kd值最大为160mL/g;铅的分配系数远大于汞,当pH值介于6~10之间时,铅在上述土壤中的Kd值为16 800~29 500mL/g。  相似文献   

植物中汞的研究进展   总被引：9，自引：1，他引：9  

付学吾  冯新斌  王少锋  李仲根  李平 《矿物岩石地球化学通报》2005,24(3):232-238

植物生态系统中汞的环境过程是生物地球化学循环过程的重要组成部分，且与整个生态系统中各物种的生存和发展密切相关。本文介绍了植物中汞生物地球化学循环的进展，包括汞对植物的生物毒性、植物中汞的来源、分布与迁移转化、植物大气间汞的交换过程及其研究方法，以及植被在生态系统间汞循环中的重要作用，最后简要介绍今后的研究重点和热点。  相似文献   

王水水浴消解-冷原子荧光法测定土壤和沉积物中的总汞   总被引：30，自引：3，他引：30  

李仲根  冯新斌  何天容  阎海鱼  LIANG Lian 《矿物岩石地球化学通报》2005,24(2):140-143

土壤和沉积物中的总汞是环境监测的常规项目。不同消解方法对测定结果和分析进度影响较大。本文改进了与其它强氧化体系消解样品具有可对比性的传统王水消解法，利用王水在95℃水浴中一次消解，结合BrCl氧化-SnCl2还原-汞蒸汽吹脱金管预富集-冷原子荧光法测定了土壤和沉积物样品中的总汞。该方法操作简单，数据可靠，精度高，土壤和沉积物标准样品测定的相对误差为-4．6％～10．1％，回收率91．1％～111．6％；平行样测定重现性良好，提高了分析速度和准确度。  相似文献   

Screening of Mercury and Persistent Organochlorine Pollutants in Long-Finned Pilot Whale (Globicephala melas) in the Faroe Islands     

Maria Dam  Dorete Bloch 《Marine pollution bulletin》2000,40(12):1090-1099

Results of mercury and organochlorine analyses in pooled muscle and blubber samples representing in all 417 long-finned pilot whales (Globicephala melas) sampled in 1997 in the Faroe Islands are presented. The 28 pooled muscle samples from (in all) 9 pods were analysed for total mercury and the same number of pooled blubber samples were analysed for PCB (IUPAC CBs no. 28, 52, 99, 101, 105, 118, 128, 138, 153, 170, 180, 183 and 187), p,p′-DDT and metabolites and o,p′-DDT and metabolites, cis () and trans (γ)-chlordane, cis- and trans-nonachlor, oxychlordane, mirex, hexachlorobenzene, β-HCH and toxaphene (Parlars no. 26 (T2), 32, 50 (T12), 62 (T20) and 69.  相似文献   

Interactions of chlorpyrifos and methyl mercury: a mechanistic approach to assess chemical mixtures   总被引：1，自引：0，他引：1  

J. A. Steevens  W. H. Benson   《Marine environmental research》2000,50(1-5):113-117

The mechanism of interaction between chlorpyrifos, an organophosphate insecticide, and methyl mercury was assessed utilizing the amphipod, Hyalella azteca. Previous studies have demonstrated that chlorpyrifos and methyl mercury interact additively with survival as the endpoint. In addition, exposure to chlorpyrifos and methyl mercury increased the accumulation and decreased the elimination of methyl mercury. To further examine the mechanism responsible for these interactions, the in vivo and in vitro inhibition of acetylcholinesterase enzyme activity was assessed following exposure to methyl mercury and chlorpyrifos. In vivo, methyl mercury antagonized the effects of chlorpyrifos on acetylcholinesterase inhibition. Additional studies demonstrated that methyl mercury did not affect the in vitro bioactivation of chlorpyrifos or the subsequent inhibition of acetylcholinesterase enzyme activity. Chemical-chemical interactions were examined utilizing chromatographic techniques and suggested the formation of a chlorpyrifos-methyl mercury complex. The formation of this complex may result in increased accumulation of methyl mercury, apparent additive toxicity, and protection against chlorpyrifos-mediated acetylcholinesterase inhibition.  相似文献   

Heavy Metal Contents in Soft-Bottom Marine Macrophytes and Sediments Along the Mediterranean Coast of Spain     

Carles Sanchiz  Antonio M. García-Carrascosa  & Augustin Pastor 《Marine Ecology》2000,21(1):1-16

Abstract. Hg, Cd, Pb and Zn concentrations were determined in sediment and in tissues of five species of soft-bottom marine macrophytes ( Posidonia oceanica, Cymodocea nodosa, Zostera noltii, Ruppia cirrhosa and Caulerpa prolifera ) along the Spanish Mediterranean coast. Levels of metals were low in most of the sampling stations and similar to those found by other authors in uncontaminated zones. Certain locations, however, showed some degree of contamination (Cambrils, Almassora, Alacant, Mar Menor and El Portús). In Santa Pola we found high contents of metals in one sample of sediment due to the high proportion of the fine fraction (particules < 63µm) and organic matter, but not in the seagrass species. Mercury and zinc concentrations in the sediment are correlated to those in at least some anatomic fractions of Posidonia oceanica, Cymodocea nodosa and Caulerpa prolifera , suggesting that these species reflect the levels of these metals in the environment. Lead contents in the alga Caulerpa prolifera are also correlated to those in the sediment, while no significant correlations were obtained for cadmium. Among the species studied, Posidonia oceanica and Cymodocea nodosa seem to be better biomonitors than Caulerpa prolifera .  相似文献   

水化后GCL中膨润土的微观结构研究     

徐超  李志斌  黄亮 《岩土力学》2006,27(Z2):607-610

近年来土工织物膨润土垫（GCL）被越来越多地应用到各种防渗工程之中,而水化后GCL中膨润土的微观结构会对GCL的长期防渗性能和力学性能产生影响。采用压汞试验,对水化后GCL中膨润土的微观结构进行定量分析,研究了液体对微观结构的影响,并通过化学分析来揭示液体产生影响的机制。结果表明,(1) 采用垃圾渗滤液水化后的膨润土孔隙体积密度最大,大孔径孔隙所占比例最高;(2) 出现上述规律的原因可以归结为两个方面,一是由于渗滤液中阳离子浓度最高而使得蒙脱石表面双电层厚度最小,二是更加频繁的离子交换作用使得蒙脱石表面大直径离子比例最高。  相似文献   

冲击压实路基黄土的微观特征研究   总被引：6，自引：5，他引：1  

王生新  韩文峰  谌文武  梁庆国 《岩土力学》2006,27(6):939-944

采用扫描电镜和压汞试验研究了天然黄土和冲击压实8～40遍路基黄土的微观结构和孔隙特征。结果表明：天然黄土和冲击压实8遍的路基黄土,其微结构以粒状架空结构为主;冲击压实16～40遍,土的微结构变成粒状镶嵌结构。冲击压实16遍前后,土的孔隙直径分布在0.006～164 μm之间,平均孔径从0.767 9 μm降低到0.0 711 μm,中等孔径从5.264 μm减少到0.568 4 μm;但孔隙表面积从0.624 m2/g增加到7.517 m2/g。孔径分布在10 μm和2 μm处出现分界值,16遍前2  相似文献