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791.
基于MapInfo的矿山通风安全信息系统开发   总被引:1,自引:0,他引:1  
根据现代矿山通风系统对人机交互的要求,利用OLE技术和VisualBasic编程语言,对MapInfo进行二次开发,形成了矿山通风安全信息系统。所开发的系统集成了MapInfo强大的地图、信息、数据库等的管理功能,实现了电子地图与数据库的自动连接和双向查询,完成了信息的可视化管理,并可与生产监控、调度系统集成,用于指导煤矿安全生产,防止重大事故发生。该系统具有修改通风图、生成通风管理报表、备份数据等功能,同时还可以对通风系统中的防瓦斯突出、防尘、防火、安全管理、风机等日常管理数据进行处理,在实际应用中取得了良好的效果。  相似文献   
792.
发挥专业救援作用,加强装备与技术保障   总被引:3,自引:0,他引:3  
此次汶川大地震带给我们巨大伤痛,也引起社会各界的许多思考。就地震救援和救援过程中的个体防护问题,我们于2008年6月30日访问了中国地震局震灾应急救援司。  相似文献   
793.
The purpose of this study was to determine and evaluate the spatial changes in soil salinity by using geostatistical methods. The study focused on the suburb area of Beijing, where urban development led to water shortage and accelerated wastewater reuse to farm irrigation for more than 30 years. The data were then processed by GIS using three different interpolation techniques of ordinary kriging (OK), disjunctive kriging (DK), and universal kriging (UK). The normality test and overall trend analysis were applied for each interpolation technique to select the best fitted model for soil parameters. Results showed that OK was suitable for soil sodium adsorption ratio (SAR) and Na+ interpolation; UK was suitable for soil Cl? and pH; DK was suitable for soil Ca2+. The nugget-to-sill ratio was applied to evaluate the effects of structural and stochastic factors. The maps showed that the areas of non-saline soil and slight salinity soil accounted for 6.39 and 93.61 %, respectively. The spatial distribution and accumulation of soil salt were significantly affected by the irrigation probabilities and drainage situation under long-term wastewater irrigation.  相似文献   
794.
为了解西南某煤矿周边农用地土壤重金属污染状况,分析测试了84件表层土壤样品8种重金属元素,进行了重金属污染评价和生态风险评价。结果表明,研究区土壤重金属均高于渝西地区背景值,Cd污染较明显。从潜在生态危害风险评价看,Hg、Cd是主要生态危害元素。  相似文献   
795.
• The recharge pond dwelling process induced changes in cell properties. • Cell properties and solution chemistry exerted confounding effect on cell transport. E. coli cells within different recharge water displayed different spreading risks. Commonly used recharge water resources for artificial groundwater recharge (AGR) such as secondary effluent (SE), river water and rainfall, are all oligotrophic, with low ionic strengths and different cationic compositions. The dwelling process in recharge pond imposed physiologic stress on Escherichia coli (E. coli) cells, in all three types of investigated recharge water resources and the cultivation of E. coli under varying recharge water conditions, induced changes in cell properties. During adaptation to the recharge water environment, the zeta potential of cells became more negative, the hydrodynamic diameters, extracellular polymeric substances content and surface hydrophobicity decreased, while the cellular outer membrane protein profiles became more diverse. The mobility of cells altered in accordance with changes in these cell properties. The E. coli cells in rainfall recharge water displayed the highest mobility (least retention), followed by cells in river water and finally SE cells, which had the lowest mobility. Simulated column experiments and quantitative modeling confirmed that the cellular properties, driven by the physiologic state of cells in different recharge water matrices and the solution chemistry, exerted synergistic effects on cell transport behavior. The findings of this study contribute to an improved understanding of E. coli transport in actual AGR scenarios and prediction of spreading risk in different recharge water sources.  相似文献   
796.

Identification of different pollution sources in groundwater is challenging, especially in areas with diverse land uses and receiving multiple inputs. In this study, principal component analysis (PCA) was combined with geographic information system (GIS) to explore the spatial and temporal variation of groundwater quality and to identify the sources of pollution and main factors governing the quality of groundwater in a multiple land-use area in southwestern China. Groundwater samples collected from 26 wells in 2012 and 38 wells in 2018 were analyzed for 13 water quality parameters. The PCA results showed that the hydro-geochemical process was the predominant factor determining groundwater quality, followed by agricultural activities, domestic sewage discharges, and industrial sewage discharges. Agriculture expansion from 2012 to 2018 resulted in increased apportionment of agricultural pollution. In contrast, economic restructure and infrastructure improvement reduced the contributions of domestic sewage and industrial pollution. Anthropogenic activities were found the major causes of elevated nitrogen concentrations (NO3?, NO2?, NH4+) in groundwater, highlighting the necessity of controlling N sources through effective fertilizer managements in agricultural areas and reducing sewage discharges in urban areas. The applications of GIS and PCA successfully identified the sources of pollutants and major factors driving the variations of groundwater quality in tested years.

  相似文献   
797.
为推动我国绿色、稳定、可持续化发展,我国对环境保护工程越来越重视,企业、人们也逐渐认识到环境保护的重要作用。环境评价作为环保工程的重要技术环节,是解决环保工程不足,推动环保工程发展的重要技术。本文从环境评价的角度,解读了企业、政府、社会应当如何推动环保工程的发展。  相似文献   
798.
We report on the rates of decomposition of a group of N-methylcarbamate (NMC) pesticides (carbaryl, carbofuran and propoxur) under pre-determined tropical field conditions. Rates of decomposition for three NMCs were determined at pH 7.08 and T?=?20?°C and pH 7.70 and T = 33?°C respectively, as follows: carbaryl (78?days and 69?days); carbofuran (143?days and 83?days) and propoxur (116?days and 79?days). Investigation on methods for removal of NMCs and their phenolic decomposition products shows that activated charcoal outperforms zeolite, alumina, diatomaceous earth, cellulose and montmorillonite clay in the removal of both NMCs and phenols from aqueous solution. Furthermore, metal complexation studies on the NMCs and phenols showed that Fe (III) forms a complex with isopropoxyphenol (IPP) within which the Fe:IPP ratio is 1:3, indicative of the formation of a metal chelate complex with the formula Fe(IPP)3.  相似文献   
799.
ABSTRACT

This paper investigates the spatial effect of environmental regulation measures on the upgrading of industrial structure in the integrated development strategy of Beijing-Tianjin-Hebei region and its surrounding areas. In order to reflect the effect of the environmental regulation and different regulation measures more truly, this paper constructs indices of the environmental regulation measures through the results of policy texts quantification. On the basis of the previous research, this paper divides environmental regulation into the following types: personnel and administrative measures of command and control; market-oriented fiscal, taxation, financial and other economic measures; guidance measures. Spatial panel regression results show that administrative measures of command control and market-oriented fiscal measures have a significant role in promoting regional industrial structure upgrading, but not conducive to the advancement of the industrial structure of adjacent areas. Their roles in promoting and inhibition are counteracted, which causes the total effect of industrial structure upgrading of Beijing-Tianjin-Hebei and the surrounding areas are not significant. Personnel measures, financial measures, other economic measures and guidance measures do not have the short-term effect and spatial effect on the upgrading of industrial structure.  相似文献   
800.
利用厌氧菌发酵产物处理含铅废水及机理研究   总被引:1,自引:1,他引:0  
针对传统方法去除废水中重金属铅的缺陷,利用4株厌氧微生物的发酵产物,在不同投加量、pH、温度和反应时间下研究该产物的除铅效果。通过正交实验确定了微生物发酵产物对含铅废水处理的最佳反应条件为:发酵产物投加量为0.5 g,反应时间为20 min,pH=6,温度20℃,铅的去除率99.4%以上,并用蓄电池厂的实际废水进行验证实验,获得相同的效果;同时通过扫描电子显微镜和X-射线能量散射光谱分析厌氧细菌代谢的混合物成分,对去除机理进行了初步探讨,为生物技术处理含铅废水提供了一种新方法和理论依据。  相似文献   
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