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941.
吴秀萍 《云南环境科学》2005,24(Z1):182-183
通过对原子荧光光谱仪的性能及测试条件进行多次试验,选择了最佳的分析测试条件,建立了测定水中砷、汞新的分析方法。该法操作简单,快速,其精密度和准确度均能满足测定要求。  相似文献   
942.
中国城市汞污染及防治对策   总被引:16,自引:0,他引:16  
简要综述了当前中国城市的汞污染状况。中国许多工业城市大气中的汞含量是纽约市大气中汞含量的数倍,甚至上百倍,在采暖期城市大气的汞污染更加严重;城市土壤中的汞含量是土壤环境背景值的数倍;河流的城市河段河水中汞质量浓度普遍很高,水质多在Ⅲ-V类;城市中的植物均有不同程度地受到汞污染,其汞含量高于国外城市的植物的汞含量;城市居民膳食中鱼的汞含量很高,对城市居民的健康产生了危害;城市居民头发中的汞质量分数大多低于1rng~kg。分析了我国城市中汞的来源并提出了防治城市汞污染的对策。  相似文献   
943.
Human mercury (Hg) exposure in two contrasting areas of mining and mineral processing activity on the Philippine islands of Mindanao and Palawan was evaluated using hair analysis. On Mindanao, samples were collected from residents of Apokon, a major regional centre for gold beneficiation. On Palawan, a former cinnabar mine and mine-waste disposal site in Honda Bay formed the focus of investigation. Relatively high hair Hg burdens (up to 13mg Hg kg–1 at Apokon and 18.5mg Hg kg–1 in Honda Bay) were observed in both populations, with occupational factors apparently constituting a first-order exposure control. At Apokon, hair burdens in excess 2mg Hg kg–1 were recorded in 90% of Au processing plant workers, compared with 21% of other sectors of the population. In Bay, ex-mineworkers, although possibly subject to occupational Hg exposure in the past, now display no evidence of this influence. Fishermen, however, systematically yielded hair Hg concentrations a factor of 2.5 higher than those of the remaining population. Approximately 7% of the Apokon and Honda Bay residents sampled presented hair Hg concentrations equal to or in excess of the World Health Organisation (WHO) reference dose. There is little evidence to indicate that residential factors significantly influence Hg exposure in either area. Hazard mitigation strategies involving the isolation of resident populations from perceived contaminant sources such as ore processing plant and sites of mine-waste disposal are, therefore, unlikely to prove beneficial.  相似文献   
944.
Health risks of gold miners: a synoptic review   总被引:1,自引:0,他引:1  
Health problems of gold miners who worked underground include decreased life expectancy; increased frequency of cancer of the trachea, bronchus, lung, stomach, and liver; increased frequency of pulmonary tuberculosis (PTB), silicosis, and pleural diseases; increased frequency of insect-borne diseases, such as malaria and dengue fever; noise-induced hearing loss; increased prevalence of certain bacterial and viral diseases; and diseases of the blood, skin, and musculoskeletal system. These problems are briefly documented in gold miners from Australia, North America, South America, and Africa. In general, HIV infection or excessive alcohol and tobacco consumption tended to exacerbate existing health problems. Miners who used elemental mercury to amalgamate and extract gold were heavily contaminated with mercury. Among individuals exposed occupationally, concentrations of mercury in their air, fish diet, hair, urine, blood, and other tissues significantly exceeded all criteria proposed by various national and international regulatory agencies for protection of human health. However, large-scale epidemiological evidence of severe mercury-associated health problems in this cohort was not demonstrable.  相似文献   
945.
Idrija mine, the second largest mercury mine in the world, was in use since 1490. More than 107 000 tons of Hg were produced in its five centuries of history until 1990 when production was reduced to a few hundred kilos per year. The average recovery rate of mercury has been estimated to 73%; much of the remaining 27% was dissipated into the environment. In spite of present minimal levels of production, and only a few days of smelter operation per year, a real time survey with a mercury Zeeman analyser in a car showed relatively high mercury concentrations in the air. Amounts of 300--4000 ng Hg m-3 have been found around both the major sources of mercury vapour, the smelter and mine ventilation shaft -- while the amounts at the Old Place, at the City Museum, and near the Nikova-Idrijca confluence are of the order of 50 ng m-3. Polluted air will be transported from those sources to a degree which depends on the weather conditions, mainly the direction and intensity of the wind. The high mercury contents in the air are not only due to anthropogenic sources (smelter and the ventilation shaft, dumps and smelter slag used in construction), but may also partly be natural as in the Pront area, where the outcropping bedrock contains native mercury.  相似文献   
946.
氯元素对烟气中汞的形态和分布的影响   总被引:22,自引:2,他引:22  
采用化学热力平衡分析方法研究了在煤燃烧在气化过程中产生的瀵气里痕量元素汞的形态及分布,在一个大气压下,400K-2000K温度范围里,研究了汞-煤系统和汞-煤-氯系统中汞在还原性气氛和氧化性气氛的烟气中的化学形态和分布,着重探讨了煤中的氯元素对汞在烟气中的形态和分布的影响,化学热力平衡分析结果表明,在煤燃烧和气化的最高温度区域里,单质汞是示是主要形式,少量的氯元素可以大大地增强汞元素的蒸发;在气化的还原性气氛烟气中,汞的主要形式是单质汞,在氧化性气氛的燃煤烟气中随着在烟气中温度的降低,单质汞将发生化学反应而生成氯化汞;烟气中氯元素的含量越大,氯化汞作为稳定相的温度范围越宽。  相似文献   
947.
用扫描电子显微镜-X射线能谱仪测定了鲤鱼、脑、肝胰脏等器官中元素Na、P、K的含量比与其对汞吸收量之间的关系。结果表明,经高浓度汞(0.1mg/L)处理的鱼体组织中含汞量与Na呈正相关,与P、K呈负相关;经低浓度处理(0.01mg/L),其相关性不明显,但其净效应差值(ΔHg)与各元素含量比有密切关系,即ΔHg=0时比值最高。  相似文献   
948.
冷原子吸收测汞方法的改进   总被引:1,自引:0,他引:1  
李世萍 《云南环境科学》1996,15(4):60-62,14
本文通过测试分析,证实在冷原子吸收法测定汞的过程中,用3%HNO3溶液代替5%HNO3-0.05%K2Cr2O7溶液作固定液,使标准溶液和水样测试条件一致,空白吸光度降低,样品吸光度误数更准确,读差更小。  相似文献   
949.
用自制的冷原子汞蒸气发生装置和样品吸收管,研究了以SnCl_2为还原剂,冷原子吸收分光光度法连续测定汞的适宜条件.检出限为0.45ng/ml,汞量在0~80ng/ml范围内,符合比尔定律;连续测定浓度为20ng/m的汞溶液,相对标准偏差为1.8%;测定实际水样中的痕量汞,其回收率为97.0%~100.8%.  相似文献   
950.
汞在环境中的污染和迁移转化   总被引:3,自引:0,他引:3  
本文阐述了汞的污染及其来源和它在环境迁移转化规律 ,提出综合防治措施 ,以消灭汞中毒对人体健康的危害  相似文献   
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