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601.
煤矿含悬浮物矿井水净化处理技术探讨   总被引:14,自引:4,他引:14  
论述了含悬浮物矿井水净化处理利用的必要性,矿井水水质,水量和处理要求,现有的处理工艺,混凝剂及混合方式,主要处理构筑物和消毒方式等。指出了在确定处理规模,处理工艺,设计参数,药剂选择和投加过程中存在的问题,并给出了解决上述问题的方法。  相似文献   
602.
通过对垃圾填埋场设置监测井监测,讨论了垃丧填埋场封场后在内部温度,渗滤液的PH值及O2,CH4、CO2等气体浓度在时间上与空间上的变化,认为在不同到3a的时间五峰垃圾填埋场内部垃圾分解的程度就已达到整个分解过程听中后期,提出在高温高湿地区要充分利用CH4资源,必须尽快直埋尽快封场或边填埋边使用。  相似文献   
603.
定量风险评价标准探讨   总被引:12,自引:0,他引:12  
武雪芳  陈家宜 《上海环境科学》2000,19(4):152-154,158
围绕定量评价标准对风险的度量和制定风险评价标准的基本原则等方面的进展和存在的问题进行了初步的探讨,分析归纳了国处有着的个人风险和社会风险标准,提出具有重大危害性的工业设施对员工或公众造成的风险,不应显著高于人们在日常生活中接触到其他风险;每年10^-6的死亡风险是可以忽略不计的个人风险水平等观点。  相似文献   
604.
上海潮滩表层沉积物重金属的分布特征   总被引:9,自引:0,他引:9  
1998年7月、11月和1999年1月、4月,对上海潮滩进行连续采样和预测的基础上,用原子吸收法测试了110个表层沉积物中的Cu、Pb、Zn、Cr和Cd的含量,结果表明:(1)上海潮滩表层沉积物重金属含量有如下顺序:Zn〉Cu〉Cr〉Pb》Cd。(2)在自然条件下,从高潮滩到中、低潮滩,沉积物重金属的含量递减。(3)不同的采样位置对沉积物重金属的含量有显著影响。(4)根据各采样点沉积物重金属的含理  相似文献   
605.
采用SBR法处理麻生物脱胶废水,实验考察了溶解氧、曝气时间、污泥负荷与处理效果的关系。结果表明,在限制性曝气及COD  相似文献   
606.
水中酚类有机污染物HPLC分析及其应用   总被引:5,自引:0,他引:5  
陈伟  陈玲  范瑾初 《上海环境科学》2000,19(10):492-494
超声辐照技术降解水中有机污染物,其降解效率的主平价需要简单、快捷和精确的分析方法。为此研究了5种优先控制酚类污染物的HPLC分离及定量分析方法,方法的定量范围为0.4-100mg/L,检测限介于0.34-0.79ng/μL。4-氯酚的超声降解实验表明,随着反应溶液中4-氯酚初始浓度的降低,降解效率明显提高,因此该方法适用于超声降解过程中酚类污染物的跟踪测定。  相似文献   
607.
As circumstances of operating and maintenance activities for landfilling and composting in Tehran metropolis differ from those of cities in developed countries, it was concluded to have an environmental impact comparison between the current solid waste management (MSW) strategies: (1) landfill, and (2) composting plus landfill. Life cycle assessment (LCA) was used to compare these scenarios for MSW in Tehran, Iran. The Eco-Indicator 99 is applied as an impact assessment method considering surplus energy, climate change, acidification, respiratory effect, carcinogenesis, ecotoxicity and ozone layer depletion points of aspects. One ton of municipal solid waste of Tehran was selected as the functional unit. According to the comparisons, the composting plus landfill scenario causes less damage to human health in comparison to landfill scenario. However, its damages to both mineral and fossil resources as well as ecosystem quality are higher than the landfill scenario. Thus, the composting plus landfill scenario had a higher environmental impact than landfill scenario. However, an integrated waste management will ultimately be the most efficient approach in terms of both environmental and economic benefits. In this paper, a cost evaluation shows that the unit cost per ton of waste for the scenarios is 15.28 and 26.40 US$, respectively. Results show landfill scenario as the preferable option both in environmental and economic aspects for Tehran in the current situation.  相似文献   
608.
Soil conservation planning often requires estimates of the spatial distribution of soil erosion at a catchment or regional scale. This paper applied the Revised Universal Soil Loss Equation (RUSLE) to investigate the spatial distribution of annual soil loss over the upper basin of Miyun reservoir in China. Among the soil erosion factors, which are rainfall erosivity (R), soil erodibility (K), slope length (L), slope steepness (S), vegetation cover (C), and support practice factor (P), the vegetative cover or C factor, which represents the effects of vegetation canopy and ground covers in reducing soil loss, has been one of the most difficult to estimate over broad geographic areas. In this paper, the C factor was estimated based on back propagation neural network and the results were compared with the values measured in the field. The correlation coefficient (r) obtained was 0.929. Then the C factor and the other factors were used as the input to RUSLE model. By integrating the six factor maps in geographical information system (GIS) through pixel-based computing, the spatial distribution of soil loss over the upper basin of Miyun reservoir was obtained. The results showed that the annual average soil loss for the upper basin of Miyun reservoir was 9.86 t ha(-1) ya(-1) in 2005, and the area of 46.61 km(2) (0.3%) experiences extremely severe erosion risk, which needs suitable conservation measures to be adopted on a priority basis. The spatial distribution of erosion risk classes was 66.9% very low, 21.89% low, 6.18% moderate, 2.89% severe, and 1.84% very severe. Thus, by using RUSLE in a GIS environment, the spatial distribution of water erosion can be obtained and the regions which susceptible to water erosion and need immediate soil conservation planning and application over the upper watershed of Miyun reservoir in China can be identified.  相似文献   
609.
Two-year monitoring data (2006 and 2009), collected at the sub-urban site (WQS) and the background site (TH), were used to study the characteristics of Particulate Matter (PM) pollution in the Pearl River Delta region, China. Similar levels of PM(2.5) concentration measured at both sites seem to confirm that the fine particles have emerged as a major regional pollution issue. The seasonal variation of PM(2.5) concentration is associated with the regional monsoon circulations while the diurnal variation is related to land-sea breeze, traffic emissions and boundary layer development. Negative correlation was found in PM(2.5)-wind speed and PM(2.5)-humidity. Analysis of radiation, temperature and ozone suggests the existence of secondary aerosol formation. Transport effect may be another contributing factor to high PM pollution in the region, such as occasional long-distance dust intrusion and trans-boundary effects from upwind areas.  相似文献   
610.
The biogeochemical and ecological impacts of environmental nanoparticles (ENPs) are some of the fastest growing areas of research today. However, efficient separation and collection of ENPs in natural systems remains difficult. This review article is focused on experimental investigation of separation and identification of ENPs, including nanoparticles with size fractions in the range of <2000, 450 to 2000, 100 to 450 and 1 to 100 nm. An automated ultrafiltration device (AUD) was used successfully to overcome the problem of efficiently collecting ENPs in large quantities in red soils. A significant amount of hematite nanoparticles was present on the surface coating of kaolinite nanoparticles and aggregated hematite nanoparticles overlapping the edge of a kaolinite flake in a size range of 5 to 8 nm. Synchrotron XRD technique is more straightforward and powerful than conventional XRD with oriented specimens and random powder methods for identifying nanoparticles, crystallinity, and particle size in red soils, particularly for the illite, kaolinite, goethite and hematite nanoparticles. The AUD apparatus can be employed to efficiently collect large quantities of soil and related ENPs for investigation of their structural characteristics and surface properties, which have significant impact on weathering reaction pathways, catalysis, the fate of vital elements and environmental pollutants, and ecosystem restoration.  相似文献   
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