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211.
垃圾土的渗透特性试验   总被引:3,自引:0,他引:3  
用取自京郊某垃圾堆填场的垃圾土样进行渗透试验,比较不同密度情况下渗透系数的差别。试验中同时记录了渗透系数随时间的变化情况。试验结果表明,垃圾土的渗透系数随密度的不同,可以在(10-3~10-7)cm/s之间变动。试验中也发现垃圾土的渗透系数随时间而逐渐减小,大约6天左右趋于稳定。对垃圾土的渗透系数室内试验测定应以观测7天时间为宜。  相似文献   
212.
在海洋三维地震作业中,潮汐运动对地震作业影响很大,有时甚至因为潮汐对地震电缆的侧向影响需要中断作业。本文根据作业工区附近港口的潮汐数据计算推断出作业区潮汐的运行规律,遵循其规律避开潮汐的高潮期进行地震作业,以取得更好的地震采集资料和提高施工效率。  相似文献   
213.
单边界和双边界是二分式条件价值法(CVM)的2种主要问题格式。针对澳门固体废弃物管理存在的问题,应用单边界和双边界二分式条件价值法,比较研究了澳门固体废弃物管理方案改善的支付意愿及其总经济价值;结果表明,80.56%的居民对新的固体废弃物管理方案存在支付意愿。单边界二分式CVM的分析结果表明澳门居民的平均支付意愿为每人每月14.87~24.12澳门元。双边界二分式CVM的结果表明澳门居民的平均支付意愿为每人每月14.43~17.94澳门元。单边界和双边界二分式CVM的评估结果相差不大,双边界二分式CVM的评估结果较为精确。按2003年澳门总人口44.85万计算,新的固体废弃物管理方案的年总经济价值约为7.02×107澳门元。   相似文献   
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215.
The Tunnel Sealing Experiment (TSX), located on the 420 Level of the Underground Research Laboratory (URL) of Atomic Energy of Canada Limited (AECL), was used to study the behaviour of two bulkheads installed in situ: one composed of highly compacted bentonite-sand blocks, the other composed of low-heat high-performance concrete. Permeable sand was placed in an 11.2-m-long chamber between the bulkheads. The chamber was first pressurized with water to 4 MPa to simulate the conditions likely to develop in the period following installation of seals in an actual repository. A stage of circulating hot water in the chamber began on 2002 September 24. The maximum design temperature of 85 °C at the interior face of the bulkheads could not be achieved in the time available. The actual maximum temperature was 65 °C. The purpose of heating was to investigate the thermohydromechanical responses in the bulkheads and surrounding rock to increased temperature. A passive cooling stage followed the heating stage. To help understand the influence of natural cooling on the thermohydromechanical response, a series of coupled thermohydromechanical modelling exercises was carried out using the finite element program, Model Of Transport In Fractured/porous media (MOTIF), and the results were compared with measured data. The thermal response in the rock and the bulkheads was successfully simulated. The influence of hydraulic conductivity on the hydraulic response in the clay bulkhead was analyzed.  相似文献   
216.
The objective of this work is to present an example of environmental impact of barite waste management observed in stream sediments of the western part of the Kupa River drainage basin. It is a significant water resource for Croatia and a part of Slovenia. In addition, it is for both countries a region of tourism, sport and fishing. Sediments (fraction < 63 μm) collected within the whole drainage basin have shown a significant barium anomaly in the western part. The highest concentration of total barium (5790 mg/kg) was determined in Kupica, a tributary of Kupa River. The barium anomaly was traced in Kupa River about 120 km downstream. Looking for the contamination source it was found that the anomaly originates from uncareful waste disposal into an abyss, after barite separation in Homer (Lokve), Gorski Kotar, Croatia. From there barite entered Kupica River subterraneous. Barite and albite were identified by XRD near the source of Kupica River as minor minerals, while quartz and dolomite ferroan were major minerals. This preliminary report does not give yet an answer about barium solubility in river water, about its bioavailability and consequently about barium pollution in the western part of the Kupa River drainage basin, however the possibility is highlighted and discussed.  相似文献   
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218.
Even though, application of industrial effluent water may alleviate the irrigation water shortage in dry regions such as Iran, but uncontrolled discharge into environment and agricultural land may cause unirreversible harmful damage to environments. Therefore, application of industrial effluent water should consider the environmental consequences such as soil, ground water and food contamination. In this study the effect application of Zob-Ahan effluent water for irrigation water and seepage from evaporation ponds on the chemical composition of surrounding well-water were seasonally investigated from April to March in 2003. The water from the selected well was sampled and analyzed for pH, EC, nitrate, hardness, TSS, TDS, and cations including Na^+, Ca^2+, Mg^2+, anions including SO4^2-, CO3^2-, HCO3^-, Cl^-, and heavy metals including Pb, Cd, Cu, Fe, Cr, Mn, Co, and Zn . The results were compared with standard levels for ground water resources, irrigation water, and direct human consumption. The result shows that the ground water in the vicinity of effluent water application fields and evaporation ponds is contaminated and the concentrations of NO3, Cl and Fe are higher than standard permissible levels for ground water resources. For irrigation or discharge into absorption well the heavy metal concentrations of Cu, Cr, Co, and Fe are limiting.  相似文献   
219.
以北方某燃料乙醇生产系统为例,从物质、能量和水的流动等方面定量地分析其实践循环经济的情况,并结合清洁生产指标体系做了对比分析。着重分析了此生产系统的废物链的组成及其作用,并探讨了进一步发展循环经济的措施。结果表明:燃料乙醇生产系统的原料为可再生资源,主要产品燃料乙醇具有环境友好性;废物链的存在提高了物质利用率、能量利用率和能量保有率,减少了废物的排放,提高了经济效益;通过对废物链的补充还可进一步体现循环经济特性。  相似文献   
220.
 Deep-well injection has been used to dispose of municipal liquid wastes in southwestern Florida since 1988. The liquid wastes are injected into an extremely high-transmissivity zone of fractured dolomite in the Early Eocene Oldsmar Formation of the Floridan aquifer system; this zone is commonly referred to as the Boulder Zone. Data collected during the drilling and operational testing of southwestern Florida injection wells provide insights into the nature of the injection zone and overlying confining beds. The location of high-transmissivity zones that are capable of accepting large quantities of waste water is vertically and horizontally variable and cannot be predicted with certainty. A 40.9-m thick high-permeability interval in one injection well, for example, was absent in a well drilled only 85.4 m away. Some upward migration of low-density injected fluids has occurred, but at no site were the injected liquids detected in deep monitor wells, such as occurred at injection-well sites along the coasts of southeastern, west-central, and east-central Florida. The primary confinement of the injected liquids (i.e., deepest effective confining beds) consists of unfractured beds of low-permeability dolomite within the Oldsmar Formation, whose locations are also laterally and vertically variable. The origin and controls of the distribution of fractures in the Oldsmar Formation are poorly understood. Received, December 1997 Revised, June 1998, August 1998 Accepted, August 1998  相似文献   
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