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601.
农药在生态环境中的持久性及残留的研究方法   总被引:2,自引:0,他引:2  
莫汉宏  李本昌 《环境化学》1994,13(3):218-221
本文报导农药在生态环境中的持久性及残的研究方法,它包括农药在作物、土壤和水等环境介质中的持外性,以及农药在这些介质中中的残留量与农药的施用量和施药次数的关系等方面的内容,本文还介绍了农药在作物中最高残留限量与安全间隔期的计算方法。  相似文献   
602.
Natural spring water has unique properties, as it is rich in minerals that are considered to be beneficial to human health. A survey of the microbiological quality of natural spring water was conducted to assess possible risks from the consumption of the water by visitors in recreational mountain areas located in Seoul, South Korea. The densities of total coliforms and Escherichia coli were measured during the spring and the summer of 2002 to investigate the presence of coliform bacteria in the drinking spring waters. Total coliforms were detected in all samples and the mean density of total coliforms was up to a maximum of 228 CFU/mL. Detectable E. coli was found in 78% of all samples and the mean densities of E. coli varied from a minimum of 0 CFU/mL to a maximum of 15 CFU/mL in all samples. Malfunctioning septic systems and wildlife population appear to be the main source of E. coli contamination. Presence of E. coli in natural spring water indicates potential adverse health effects for individuals or populations exposed to this water. The fecal contaminated spring water may present an unacceptable risk to humans if it is used as raw drinking water.  相似文献   
603.
Efficient removal of formaldehyde from indoor environments is of significance for human health.In this work,a typical binary transition metal oxide that could provide various oxidation states,β-NiMoO_4,was employed as a support to immobilize the active Pt component(Pt/NiMoO_4) for catalytic formaldehyde elimination at low ambient temperature(15℃).The results showed that the hydrothermal preparation temperature and time had a noticeable impact on the morphology and catalytic activity of the samples.The catalyst prepared with hydrothermal temperature of 150℃ for 4 hr(Pt-150-4) exhibited superior catalytic activity and stability mainly due to its distinctly porous structure,relative abundance of adsorbed surface hydroxyls/water,and high oxidation ability,which resulted from the interaction of Pt with Ni and Mo of the bimetallic NiMoO_4 support.Our results might shed light on the rational design of multifunctional catalysts for removal of indoor air pollutants at low ambient temperature.  相似文献   
604.
The Jialu River in China has been seriously polluted by the direct discharge of industrial and domestic wastewater. The predominant contaminants of the Jialu River and its adjacent groundwater were recently investigated. However, the potential genotoxic impact of polluted water on human health remains to be clarified. Here, we used human–hamster hybrid(A_L) cells, which are sensitive for detecting environmental mutagens. We found that the cytotoxicity and mutagenicity of the groundwater in the Jialu River basin were influenced by the infiltration of the Jialu River. Hydrological periods significantly affected the cytotoxicity, but not the mutagenic potential, of surface and groundwater. Further, the mutagenic potential of groundwater samples located 1 km from the Jialu River(S_(M-2) water samples) was detected earlier than that of groundwater samples located approximately 20 km from the Jialu River(S_N water samples). Because of high cytotoxicity, the mutagenic potential of water samples from the Jialu River(S_(M-1) water samples) was not significantly enhanced compared with that of untreated controls. To further assess the mutagenic dispersion potential, an artificial neural network model was adopted. The results showed that the highest mutagenic potential of groundwater was observed approximately 10 km from the Jialu River. Although further investigation of mutagenic spatial dispersion is required, our data are significant for advancing our understanding of the origin, dispersion,and biological effects of water samples from polluted areas.  相似文献   
605.
Fluidized bed and induced crystallization technology were combined to design a new type of induced crystallization fluidized bed reactor. The added particulate matter served as crystal nucleus to induce crystallization so that the insoluble material, which was in a saturated state, could precipitate on its surface. In this study, by filling the fluidized bed with quartz sand and by adjusting water p H, precipitation of calcium carbonate was induced on the surface of quartz sand, and the removal of water hardness was achieved.With a reactor influent flow of 60 L/hr, a fixed-bed height of 0.5 m, pH value of 9.5, quartz sand nuclear diameter of 0.2–0.4 mm, and a reflux ratio of 60%, the effluent concentration of calcium hardness was reduced to 60 mg/L and 86.6% removal efficiency was achieved. The resulting effluent reached the quality standard set for circulating cooling water. Majority of the material on the surface of quartz sand was calculated to be calcium carbonate based on energy spectrum analysis and moisture content was around 15.994%. With the low moisture content, dewatering treatment is no longer required and this results to cost savings on total water treatment process.  相似文献   
606.
在宜昌环境总体规划(2013-2030)得到市人大批复实施的背景下,为共享环境总体规划生态功能红线、环境质量红线与资源开发红线("三条红线")、为满足提供规划实施与评估有效途径的实际需求,在市信息办及环保局现有业务信息系统现状评价基础上,综合运用GIS、海量空间数据管理、SOA架构、瓦片地图分发、移动GIS等技术,设计开发了宜昌市环境总体规划信息管理与应用系统(V1.0),实现了"三条红线"等相关数据成果的地图展示、查询等精确管理分析以及项目环境影响评价的辅助决策.  相似文献   
607.
随着中国经济的发展,无论是政府部门、科研机构,还是社会公众都对实验室的能力更为关注,实验室需要通过外部机构的评审,赢得外界对自身能力的信任,提高实验室的知名度.实验室计量认证工作,一般是按照《实验室资质认定评审准则》的要求,建立并运行质量管理体系.内部审核(以下,简称“内审”)是质量管理体系运行中必须进行的一项质量管理活动,内审是保证质量管理体系有效运行的重要手段.文章对内审各个环节中存在的一些问题进行了分析,提出了改进的建议和应注意的事项,对有效开展实验室内审有一定的借鉴意义.  相似文献   
608.
微生物磁效应在废水处理中的应用   总被引:9,自引:0,他引:9  
安燕  程江  杨卓如  肖立军  王锐 《化工环保》2006,26(6):467-470
介绍了微生物磁效应的原理和作用方式,综述了近年来国内外将微生物磁效应应用于活性污泥法、生物接触氧化法和酶法废水生物处理中的研究进展,指出了开发磁性生物亲和亲水填料是微生物磁效应运用于生物接触氧化废水处理技术的发展方向。  相似文献   
609.
分析了中国石油石化海外项目所在地区宗教禁忌,总结海外项目HSSE管理的经验,对可能遇到的宗教禁忌冲突提出对策。  相似文献   
610.
矿化垃圾生物反应床处理渗滤液技术研究   总被引:4,自引:0,他引:4  
实验准好氧型矿化垃圾生物反应床出水水质与配水水力负荷、配水频次及进水浓度的关系及准好氧型二级串连工艺对渗滤液的处理效果。结果表明,准好氧型矿化垃圾生物反应床在处理渗滤液时配水负荷宜不大于0.026L/(kg垃圾.次),进水CODCr浓度在10000mg/L时,其对CODCr的去除率在82%以上,而对氨氮的去除率可达99.7%以上。准好氧型二级串连工艺处理渗滤液其出水水质满足GB16889-1997二级排放标准,该工艺氨氮的出水远远低于16889-1997一级排放标准。  相似文献   
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