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251.
为明确地下水污染修复技术在世界范围的研究布局和发展态势,本研究基于智慧芽全球专利数据库对1989-2018年地下水污染修复技术专利进行计量学统计,并探讨该技术的研究布局、研究重点及授权趋势。结果显示,从申请量来看,世界范围内地下水污染修复技术涉及的申请量逐渐增长,但绝对申请量和专利授权比相对较低,地下水污染修复技术研发的重视程度依然不够,有待进一步加强;中国是该技术领域主要专利申请国,也是最大的技术来源国;科研单位在该领域的研发实力显著高于企业机构。基于以上研究,认为今后应加强研发,并且创造高效经济的地下水污染修复技术,注重科研机构与企业单位合作及已有专利成果的转化,促进专利的市场应用,使其发挥更大的社会和经济效益。  相似文献   
252.
In Egypt, production has a high priority. To this end protecting the quality of the groundwater, specifically when used for drinking water, and delineating protection areas around the drinking water wellheads for strict landuse restrictions is essential. The delineation methods are numerous; nonetheless, the uniqueness of the hydrogeological, institutional as well as social conditions in the Nile Delta region dictate a customized approach. The analysis of the hydrological conditions and land ownership at the Nile Delta indicates the need for an accurate methodology. On the other hand, attempting to calculate the wellhead protected areas around each of the drinking wells (more than 1500) requires data, human resources, and time that exceed the capabilities of the groundwater management agency. Accordingly, a combination of two methods (simplified variable shapes and numerical modeling) was adopted. Sensitivity analyses carried out using hypothetical modeling conditions have identified the pumping rate, clay thickness, hydraulic gradient, vertical conductivity of the clay, and the hydraulic conductivity as the most significant parameters in determining the dimensions of the wellhead protection areas (WHPAs). Tables of sets of WHPAs dimensions were calculated using synthetic modeling conditions representing the most common ranges of the significant parameters. Specific WHPA dimensions can be calculated by interpolation, utilizing the produced tables along with the operational and hydrogeological conditions for the well under consideration. In order to simplify the interpolation of the appropriate dimensions of the WHPAs from the calculated tables, an interactive computer program was written. The program accepts the real time data of the significant parameters as its input, and gives the appropriate WHPAs dimensions as its output.  相似文献   
253.
We create a proxy for the cost of irrigation water in Georgia from a sample of Georgia irrigators by investigating the marginal cost of pumping groundwater. We then combine this proxy with agronomic and climatic variables to estimate the response of agricultural water use to differences in the marginal cost of irrigation. The results show that pumping costs are a significant determinant of water use, and imply that agricultural water use would be moderately affected by institutional changes that would explicitly price water.  相似文献   
254.
In present study focus has been given on estimating quality and toxicity of waste with respect to heavy metals and its impact on groundwater quality, using statistical and empirical relationships between different hydrochemical data, so that easy monitoring may be possible which in turn help the sustainable management of landfill site and municipal solid waste. Samples of solid waste, leachate and groundwater were analyzed to evaluate the impact of leachates on groundwater through the comparison of their hydrochemical nature. Results suggest the existence of an empirical relationship between some specific indicator parameters like heavy metals of all three above mentioned sample type. Further, K/Mg ratio also indicates three groundwater samples heavily impacted from leachate contamination. A good number of samples are also showing higher values for and Pb than that of World Health Organization (WHO) drinking water regulation. Predominance of Fe and Zn in both groundwater and solid waste samples may be due to metal plating industries in the area. Factor analysis is used as a tool to explain observed relation between numerous variables in term of simpler relation, which may help to deduce the strength of relation. Positive loading of most of the factors for heavy metal clearly shows landfill impact on ground water quality especially along the hydraulic gradient. Cluster analysis, further substantiates the impact of landfill. Two major groups of samples obtained from cluster analysis suggest that one group comprises samples that are severely under the influence of landfill and contaminated leachates along the groundwater flow direction while other assorted with samples without having such influence.  相似文献   
255.
通过优选色谱柱,进一步改进色谱分离条件,优化前处理方法,建立一种快速高效测定地下水中15种农药残留量的GC-MS方法。该法采用分段法选择离子(SIM)扫描,具有更高的灵敏度、较低的检出限和较高的回收率,检出限低于0.004 8μg/L,回收率为85.9%~107.4%。本方法的突出特点是前处理速度快、萃取溶剂用量少、环境污染小、色谱运行时间短,基本稳定在25 min内完成分析,适用于大批量样品检测。  相似文献   
256.
In some previous papers a probabilistic methodology was introduced to estimate a spatial index of risk of groundwater quality degradation, defined as the conditional probability of exceeding assigned thresholds of concentration of a generic chemical sampled in the studied water system. A crucial stage of this methodology was the use of geostatistical techniques to provide an estimation of the above-mentioned probability in a number of selected points by crossing spatial and temporal information. In this work, spatial risk values were obtained using alternatively stochastic conditional simulation and disjunctive kriging. A comparison between the resulting two sets of spatial risks, based on global and local statistical tests, showed that they do not come from the same statistical population and, consequently, they cannot be viewed as equivalent in a statistical sense. At a first glance, geostatistical conditional simulation may appear to represent the spatial variability of the phenomenon more effectively, as the latter tends to be smoothed by DK. However, a close examination of real case study results suggests that disjunctive kriging is more effective than simulation in estimating the spatial risk of groundwater quality degradation. In the study case, the potentially ‘harmful event’ considered, threatening a natural ‘vulnerable groundwater system,’ is fertilizer and manure application.  相似文献   
257.
Groundwater chemistry has been studied to examine the associated hydrogeochemical processes operating for the development of salinity in the groundwater in parts of Guntur district, Andhra Pradesh, India. The study area is underlain by charnockites and granitic gneisses associated with schists of the Precambrian Eastern Ghats. Groundwater is the main resource for irrigation besides drinking. Chemical parameters, pH, EC, TDS, Ca2+, Mg2+, Na+, K+, , , Cl, , , F and SiO2, are taken into account. Groundwater is of brackish type. Na+−Cl facies dominates the groundwater. Examination of compositional relations and mineral saturation states shows that the ion exchange of Ca2+ for adsorbed Na+, evapotranspiration, dissolution of soil salts, dissolution of NaCl and CaSO4, and precipitation of CaCO3 are the dominant hydrogeochemical processes associated with the groundwater composition in the area. Evapotranspiration causes accumulation of salts in the soil/weathered zone. These salts reach the water table by leaching through infiltrating recharge water. A positive relation between depth to water table and TDS with season supports this inference. The effects of human activities, such as intensive and long-term irrigation, irrigation-return-flow, application of unlimited agricultural fertilizers and recycling of saline groundwater, act to further increase the salinity in the groundwater. Therefore, the groundwater quality increases towards the flow path, while the post-monsoon groundwater shows higher concentrations of TDS, Na+, Mg2+, Cl, , , F and SiO2 ions. The study could help to understand the hydrogeochemical characteristics of the aquifer system for taking effective management measures to mitigate the inferior groundwater quality for sustainable development.  相似文献   
258.
膜界面探测器在工业污染场地调查中的应用   总被引:3,自引:0,他引:3  
膜界面探测器是一项采用直接推进技术,可实时提供场地地下挥发性有机物近乎连续分布信息的直接感测工具。以某历史上从事有机氯农药生产的废弃工业场地为例,运用该技术,配置土壤电导率传感器、电子捕获检测器以及氢火焰离子化检测器,对该场地中潜在污染区域进行快速筛选调查,初步确定了土壤和地下水中挥发性有机物污染的热点区域及其三维分布和地层信息,为后续进一步调查方案优化、场地概念模型建立及后续修复方案设计等提供了重要的信息。  相似文献   
259.
采用高分辨电感耦合等离子体质谱法测定地下水中14种稀土元素,并选择Rh作内标,可消除测定中的质谱干扰和非质谱干扰,使方法在0μg/L~100μg/L范围内线性良好。方法检出限为0.002μg/L~0.005μg/L,实际水样的加标回收率为80.0%~117%,RSD为2.1%~3.8%。  相似文献   
260.
徐州地区地下水中内分泌干扰物的监测与风险评估   总被引:4,自引:0,他引:4  
采用液相色谱-串联质谱法测定徐州地区地下水中内分泌干扰物,并用雌二醇当量EEQ计算法和风险熵RQ计算法分别对其活性和生态风险水平分析评价。结果表明,徐州地区地下水中不含雌酮(E1)、雌二醇(E2)、雌三醇(E3)、炔雌醇(EE2)等内分泌干扰物,只含有双酚A(BPA),且最高值达26.45 ng/L,提出应把BPA作为控制重点。  相似文献   
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