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1.
为了解阿拉尔河悬浮物对铀的吸附特性,通过静态吸附实验,研究了吸附时间、pH值、温度和铀初始浓度等因素对模拟含铀水中U(VI)去除率的影响,并从热力学和动力学方面对吸附过程进行了分析。结果表明,在T=25℃,溶液初始pH=7,接触时间为16 h时,悬浮物对铀的平衡吸附率最佳,为95.48%。随着铀初始浓度的增加,吸附量增加,但吸附率随之下降,升高温度有利于铀的吸附。铀在悬浮物上的吸附过程符合Langmuir等温吸附方程,说明悬浮物对铀为单分子层吸附,且化学吸附占主导地位。吸附动力学过程可用准二级吸附动力学模型描述,表明吸附主要受动力学控制,由两个以上步骤共同控制。FTIR和EDS分析结果表明,吸附过程中铀主要与悬浮物表面活性基团螯合并以表面络合吸附为主。吸附前后的能谱对比分析表明,吸附过程中存在离子交换行为。因此,悬浮物对铀的吸附机理是以表面络合吸附和离子交换为主、物理吸附为辅的混合吸附过程。 相似文献
2.
淮南采煤塌陷湖泊浮游植物优势种的营养动力学 总被引:3,自引:1,他引:2
在淮南潘谢矿区选取3个营养盐结构差异较大的塌陷湖泊,于2014—2015年4个季度分别对浮游植物群落结构组成进行调查,选取3个湖泊中的优势种(属)具尾蓝隐藻(Chroomonas caudata)、链形小环藻(Cyclotella catenata)和伪鱼腥藻(Pseudanabaena sp.)作为研究对象,设置不同的氮(N)、磷(P)浓度梯度进行营养动力学培养实验,并结合Monod方程,获得3个藻种在不同营养盐限制下的营养动力学参数.N限制下具尾蓝隐藻、小环藻和伪鱼腥藻的最大生长速率(μmax)和半饱和常数(Ks)分别为:0.66 d~(-1)、1.66 mg/L;0.37 d~(-1)、1.06 mg/L;0.71 d~(-1)、2.26 mg/L;P限制下它们的μmax和Ks则分别为:0.51 d~(-1)、0.023 mg/L;0.31 d~(-1)、0.035 mg/L;0.90 d~(-1)、0.015 mg/L.综上所述,在N充足时,伪鱼腥藻能够在竞争中形成优势,同时在P限制情况下易成为优势种,从营养动力学的角度揭示了其在塌陷湖泊中占据优势的营养盐动力学机制.研究结果可以为沉陷区水域开发利用和营养盐管理提供科学依据. 相似文献
3.
WU Ai-min HAO Ai-bing GUO Hai-peng LIU Jing-tao ZHANG Er-yong WANG Huang WANG Xin-feng WEN Xue-ru ZHANG Cui-guang 《地下水科学与工程》2020,8(3):195-209
This paper reviewed the main achievements of hydrogeological survey in China, summarized the significant progress of hydrogeological survey over the past decade, and forecasted the key responsibilities for hydrogeological survey in the p14th Five-year Planq. The significant progress includes: China established the 1: 50 000 standard hydrogeological survey system with Chinese characteristics and produced the new generation of high-quality hydrogeological maps; the national groundwater monitoring project was completed and accepted, which marks China taking the leading position in groundwater monitoring internationally; fruitful results were achieved in the national groundwater quality survey, and groundwater quality background values were basically identified and checked; hydrogeological and environmental geological survey was continuously promoted in karst areas and the ecological restoration of rocky desertification achieved remarkable results; China strengthened layer exploration techniques for groundwater, integrating the key and practical techniques of layer exploration and monitoring; the exploration of groundwater in the poverty-stricken regions and old revolutionary base areas were effectively promoted to strongly guarantee the poverty alleviation and drinking water safety; the mystery of desert groundwater was uncovered, making up for the shortage of 1: 250 000 hydrogeological survey in the Badain Jaran Desert; and more efforts were made to conduct survey on the water resources in the basin, and to finish the unified measurement of national-scale groundwater level. 相似文献
4.
Water sustainability model for estimation of groundwater availability in Kemuning district,Riau-Indonesia 下载免费PDF全文
Muhammad Juandi 《地下水科学与工程》2020,8(1):20-29
There are rising interests in the utility of groundwater in various aspects,which is capable of triggering problematic issues.The excessive exploitation for anthropologic uses,without regards to aquifer capacity,will decreases the water table as well as capacity of groundwater in the aquifer.This research was aimed to provide aquifer model of underground water by consideration of various environmental factors,with the propensity of being modeled,in an attempt to predict groundwater conditions in subsequent years.The purpose of this research was to forecast water requirements,availability,as well as three-dimensional model of groundwater depth in Kemuning,Indragiri Hilir Regency-Indonesia between 2015 and 2022.Furthermore,various environmental factors,from aquifer profiles to anthropologic demand,are taken into account in the evaluated model,including water requirements,encompassing recharge and aquifer parameters,which consists of storativity and transmissivity.From anthropologic side are domestic requirements,trade,public facilities,agriculture,and livestock.The results show that groundwater availability in Kemuning is to be safe condition,and average difference is 1.06×108 m3/yr.The coefficient of storativity and transmissivity are 16.514 m2/day and 9897.26 m2/day,respectively,while the average depth was recorded as 2.8965 m to 10.4927 m. 相似文献
5.
State of seawater intrusion and its adaptive management countermeasures in Longkou City of China 下载免费PDF全文
Longkou City is a coastal area,and lacks water resources.The overexploitation of groundwater causes seawater intrusion.At present,seawater intrudes an area of 68 km2.With the decrease of groundwater extraction,the seawater intrusion area has generally declined.The paper expounds the development process of seawater intrusion as well as the corresponding prevention and control measures of using groundwater replenishment and groundwater throttling in Longkou City.In view of the seawater intrusion problem in Longkou City,some adaptive management countermeasures are put forward,which include:Adjusting industrial and agricultural structure,promoting economic and social development to match water resources;improving water usage structure,optimizing the utilization of water resources;advancing the construction of a water-saving society,using water resources efficiently;implementing inter-basin water transfer,using water resources rationally;developing and utilizing unconventional water sources,making full use of water resources;strengthening water infrastructure construction,increasing the development and utilization potential of water resources;carrying out ecological restoration,protecting water resources and ecological environment;improving the management informationalization level,strengthening the capabilities of groundwater monitoring and management;increasing publicity,improving public awareness of participation. 相似文献
6.
Predicting groundwater level of wells in the Diyala River Basin in eastern Iraq using artificial neural network 下载免费PDF全文
Al-Mansourieh zone is a part of Al-Khalis City within the province of Diyala and located in the Diyala River Basin in eastern Iraq with a total area about 830 km2.Groundwater is the main water source for agriculture in this zone.Random well drilling without geological and hydraulic information has led the most of these wells to dry up quickly.Therefore,it is necessary to estimate the levels of groundwater in wells through observed data.In this study,Alyuda NeroIntelligance 2.1 software was applied to predict the groundwater levels in 244 wells using sets of measured data.These data included the coordinates of wells(x,y),elevations,well depth,discharge and groundwater levels.Three ANN structures(5-3-3-1,5-10-10-1 and 5-11-11-1)were used to predict the groundwater levels and to acquire the best matching between the measured and ANN predicted values.The coefficient of correlation,coefficient determination(R2)and sum-square error(SSE)were used to evaluate the performance of the ANN models.According to the ANN results,the model with the three structures has a good predictability and proves more effective for determining groundwater level in wells.The best predictor was achieved in the structure 5-3-3-1,with R2 about 0.92,0.89,0.84 and 0.91 in training,validation,testing and all processes respectively.The minimum average error in the best predictor is achieved in validation and testing processes at about 0.130 and 0.171 respectively.On the other hand,the results indicated that the model has the potential to determine the appropriate places for drilling the wells to obtain the highest level of groundwater. 相似文献
7.
《Limnologica》2020
Competition between human use and spring-dependent systems puts these systems in jeopardy. This study analyzed whether Florida springs have experienced reductions in springflow over the last century using time series data from state and federal agencies. Of 57 springs, 26 exhibited negative trends in springflow; these declines were correlated with population growth, with groundwater withdrawals, and to a lesser extent with rainfall. Even in a region with abundant rainfall, population growth has impacted spring integrity. 相似文献
8.
Groundwater contaminant source identification based on iterative local update ensemble smoother 下载免费PDF全文
Identification of the location and intensity of groundwater pollution source contributes to the effect of pollution remediation, and is called groundwater contaminant source identifcation. This is a kind of typical groundwater inverse problem, and the solution is usually ill-posed. Especially considering the spatial variability of hydraulic conductivity field, the identification process is more challenging. In this paper, the solution framework of groundwater contaminant source identification is composed with groundwater pollutant transport model (MT3DMS) and a data assimilation method (Iterative local update ensemble smoother, ILUES). In addition, Karhunen-Loève expansion technique is adopted as a PCA method to realize dimension reduction. In practical problems, the geostatistical method is usually used to characterize the hydraulic conductivity feld, and only the contaminant source information is inversely calculated in the identifcation process. In this study, the identification of contaminant source information under Kriging K-field is compared with simultaneous identification of source information and K-field. The results indicate that it is necessary to carry out simultaneous identification under heterogeneous site, and ILUES has good performance in solving high-dimensional parameter inversion problems. 相似文献
9.
Groundwater is a resource under stress. In both developed and developing countries, it has been found that increasing human influence has led to the contamination of the groundwater resource. To understand the magnitude of this problem, a study was conducted in 58 wards within Northern part of Kolkata, India, where water samples from tube wells were collected and analysed on essential drinking water quality parameters, prescribed by WHO. Using Principal component analysis, and Water quality index mapping, the aforementioned results have been interpreted. This has helped to depict that not only is the groundwater unsuitable for drinking, but that the parametric values have a tendency to increase abruptly within the shortest of ranges, indicating urban pollution as the root cause of contamination. This paper shall thus discuss the spatial change in groundwater quality in northern Kolkata and suggest measures which might be implemented to secure a sustainable future for the city. 相似文献
10.
Groundwater, as a drinking water source for nearly one third of the world’s urban population, plays a strategic role in the development of urbanization. The object of this study is urban areas with the largest demand for water resources, the heaviest load of groundwater pollution and the most intense development of underground projects. This study sorted out the eco-hydrological problems such as the variation of the groundwater hydrological process, the groundwater pollution, and the urban heat island of groundwater in urban areas under the background of urbanization. Furthermore, the mechanism of changes in the quantity, quality and heat of groundwater was also systematically analyzed, and the intrinsic interaction among these three factors was revealed. The study showed that changes in land use and land cover caused by the urbanization are the main reasons for the variation of groundwater hydrological process. The pollution load of urbanization construction and domestic production waste has aggravated the deterioration of groundwater quality. The increase in vertical heat flux caused by urbanization gives rise to the warming of groundwater. By summarizing the eco-hydrological problems and causes of groundwater in urbanized areas, several suggestions were proposed: Establishing the evaluation method and system of urban groundwater resources; Speeding up the technological breakthroughs of groundwater pollution control; Improving the regional control strategies for groundwater pollution; Optimizing the allocation of groundwater resources. This study will provide the theoretical basis and technical support for ensuring urban water safety, building ecological civilized cities and further promoting the sustainable development of economy and society. 相似文献