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排序方式: 共有144条查询结果,搜索用时 250 毫秒
1.
Synthesis of zeolites using fly ash and their application in removing heavy metals from waters 总被引:1,自引:0,他引:1
Fly ash is the solid waste of thermal power plants where coal is used as fuel, and its management and utilization have been of environmental concern for decades. Since the technique of synthesizing zeolite from coal fly ash was introduced by Holler[1] (19… 相似文献
2.
地质学家重视研究深部(变质)CO_2对古气候的影响 总被引:5,自引:0,他引:5
地质学家重视研究深部(变质)CO2对古气候的影响贾跃明(中国地质矿产信息研究院,北京,100037)近几年来,随着过去全球变化研究的兴起,地质学家越来越重视地质历史时期影响大气CO2浓度的因素的调查。不少人认为,变质作用和火山活动可能是过去大气中CO... 相似文献
3.
Sewage sludge ash (SSA), the waste generated in sewage sludge incineration, was obtained from Wuhan Sewage Treatment Plant and used as a low-cost sorbent for removing Cu(Ⅱ) from wastewaters. The sorbent was first modified with 5 % sulfuric acid to increase its sorption capacity. The specific surface area, porosity, cation-exchange capacity (CEC) and pHZPC of the sorbent were measured. Batch experiments were made to study the effect of contact time, solution pH value and temperature on sorption. Both Langmuir and Freundlich models well described the Cu(Ⅱ) sorption process, with correlation coefficient (R2) values of 0.993 4 and 0.989 9 respectively. And the sorption process follows the Lagergren first order kinetic model. The equilibrium sorption capacity of acidified SSA to Cu(Ⅱ) is estimated to be 7.78 mg/g under optimal conditions. 相似文献
4.
Groundwater sustainability and groundwater/surface-water interaction in arid Dunhuang Basin,northwest China 总被引:1,自引:0,他引:1
Jingjing Lin Rui Ma Yalu Hu Ziyong Sun Yanxin Wang Colin P. R. McCarter 《Hydrogeology Journal》2018,26(5):1559-1572
The Dunhuang Basin, a typical inland basin in northwestern China, suffers a net loss of groundwater and the occasional disappearance of the Crescent Lake. Within this region, the groundwater/surface-water interactions are important for the sustainability of the groundwater resources. A three-dimensional transient groundwater flow model was established and calibrated using MODFLOW 2000, which was used to predict changes to these interactions once a water diversion project is completed. The simulated results indicate that introducing water from outside of the basin into the Shule and Danghe rivers could reverse the negative groundwater balance in the Basin. River-water/groundwater interactions control the groundwater hydrology, where river leakage to the groundwater in the Basin will increase from 3,114?×?104 m3/year in 2017 to 11,875?×?104 m3/year in 2021, and to 17,039?×?104 m3/year in 2036. In comparison, groundwater discharge to the rivers will decrease from 3277?×?104 m3/year in 2017 to 1857?×?104 m3/year in 2021, and to 510?×?104 m3/year by 2036; thus, the hydrology will switch from groundwater discharge to groundwater recharge after implementing the water diversion project. The simulation indicates that the increased net river infiltration due to the water diversion project will raise the water table and then effectively increasing the water level of the Crescent Lake, as the lake level is contiguous with the water table. However, the regional phreatic evaporation will be enhanced, which may intensify soil salinization in the Dunhuang Basin. These results can guide the water allocation scheme for the water diversion project to alleviate groundwater depletion and mitigate geo-environmental problem. 相似文献
5.
Natural Hazards - In order to examine the height of a fractured water-conducting zone due to the presence of a fault, a typical working face in the Baodian Coal Mine which is located in the Yanzhou... 相似文献
6.
GeochemistryofThermal-MineralWatersinSiping'anDistrict,ShanxiProvince,China¥WanYanxin;SunLianfa(DepartmentofHydrogeologyandEn... 相似文献
7.
Vulnerability of groundwater in Quaternary aquifers to organic contaminants: a case study in Wuhan City,China 总被引:5,自引:0,他引:5
Yanxin Wang Broder J. Merkel Yilian Li Hui Ye Surong Fu Dana Ihm 《Environmental Geology》2007,53(3):479-484
More than 30 organic contaminants were detected in shallow groundwaters at Wuhan, the largest city in central China. Seriously
contaminated groundwaters were from densely populated, industrial and commercial areas. Abnormal concentrations were found
in groundwater from Hankou, downtown Wuhan: trimethylbenzene up to 29 μg/L, tetramethylbenzene up to 866 μg/L, and trichloroethene
up to 9.5 μg/L. Benzene, Toluene, Ethylene and Xylene (BTEX) contamination of groundwater is serious and widespread at Wuhan,
ranging between 0.14 and 25.0 μg/L. Considering the hydrogeological conditions of most Chinese cities, DRAMIC, a modified
version of the widely used DRASTIC model, was proposed by the authors for assessing vulnerability of groundwater to contamination.
The factors D, R, A and I in DRAMIC model are the same as in DRASTIC. The factor topography is ignored. The factor soil media is substituted by a new factor aquifer thickness (M) and the factor hydraulic conductivity of the aquifer by a new factor impact of contaminant (C). The equation for determining the DRAMIC Index is: DRAMIC = 5D
R + 3R
R + 4A
R + 2M
R + 5I
R + 1C
R. The calculated DRAMIC Index can be used to identify areas that are more likely to be susceptible to groundwater contamination
relative to each other. The higher the DRAMIC Index is, the greater the groundwater pollution potential. Applying DRAMIC,
a GIS-based vulnerability map for Wuhan city was prepared. Interestingly, places such as downtown Hankou, where enhanced concentrations
of BTEX have been detected, correspond quite well with those with higher DRAMIC ratings. 相似文献
8.
地下水有机污染的水文地球化学标志物探讨——以河南油田为例 总被引:4,自引:3,他引:4
经过野外现场调查和取样分析及室内研究得知南阳油田地下水已遭受不同程度的有机物污染,且污染范围可能进一步向油田南部扩散。根据近似地下水流线方向上地下水中总油质量浓度和Fe,Mn等无机组分的变化势态,结合含水介质化学分析结果,发现硫酸盐、Fe和Mn可作为地下水有机污染和地球化学标志物。在含水介质中Fe和Mn质量浓度较高的地方,地下水有机污染物降解速度快,含水介质中Fe和Mn的氧化物和氢氧化物的还原作用导致了含水层介质中Fe和Mn的缺乏和地下水中溶解Fe和Mn的积聚;在含水介质中Fe和Mn质量浓度低的地方,地下水中的有机物质量浓度并没有降低,相应地地下水中溶解Fe和Mn的质量浓度也很低。同时,由于有机污染物的存在使地下水中硫酸盐被还原,导致城下水中硫酸盐质量浓度偏低,且地下水中Fe对有机物污染的敏感性比Mn强。 相似文献
9.
TDR滑坡监测技术的研究 总被引:8,自引:0,他引:8
时间域反射测试技术(TimeDomainReflectometry)是一种电子测量技术,许多年来,一直被用于各种物体形态特征的测量和空间定位.TDR用于滑坡监测时,向埋入监测孔内的电缆发射脉冲信号,当遇到电缆在孔中产生变形时,就会产生反射波信号.经过对反射信号的分析,就能确定电缆发生形变的程度和位置.本文通过与传统的滑坡监测方法相比较,发现这种方法具有成本低、节省监测时间等特点. 相似文献
10.
古岩溶及其成矿作用的研究是鄂东南多金属成矿带沉积学和矿床学工作的较薄弱环节之一。作者依据大量野外观测资料,提出识别该区古岩溶岩系的地层、构造、形态和岩石学等四种标志及其古岩溶岩系的成因分类方案,对古岩溶在时间、空间上发育之强度、多期性及其优先发育部位亦作了分析,并阐述岩浆活动对该区古岩溶发育的影响。最后对古岩溶岩系的生成环境,形成作用和时间进行初步探讨。 相似文献