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文章速递Analysis of Gray Water Recycling by Reuse of Industrial Waste Water for Agricultural and Irrigation Purposes 认领
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作者 Safieh Javadinejad Rebwar Dara +2 位作者 Masoud Hussein Hamed Mariwan Akram Hamah Saeed Forough Jafary 《地理研究(英文)》 2020年第2期20-24,共5页
Isfahan industrial province with its numerous industrial estates in its area and consequently the amount of wastewater produced by these settlements is very difficult to deal with.Therefore,the need for proper wastewa... Isfahan industrial province with its numerous industrial estates in its area and consequently the amount of wastewater produced by these settlements is very difficult to deal with.Therefore,the need for proper wastewater treatment and efficient management of industrial waste water from the industrial estates of this province should be seriously addressed and followed up by the authorities.The purpose of this study is the feasibility of reuse of wastewater from industrial settlements for agricultural and irrigation purposes.The present study is a descriptive cross-sectional study.In this study,the average values obtained from the sampling and the results of the experiments on waste water from the industrial waste water treatment plant in Isfahan,2017,have been used.Average values of BOD5,COD,TSS and so on were compared with the standards set by the Environmental Protection Agency and analyzed in Excel software.According to the results,the average values of COD,BOD5,TSS,SO4,pH and catalyst quality parameters were determined from wastewater effluents of 315,162,93,164(mg/L),8.3 and 32.5(NTU)respectively.The results of the study show that the average values of the quality parameters examined from the effluent of the treatment plant other than BOD5 and COD are within the standard range and the limit for agricultural and irrigation purposes,which may lead to undesirable environmental performance of these two parameters. 展开更多
关键词 Gray water Water recycle Water quality Irrigation water users Industrial users
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Moving-Water Equilibria Preserving HLL-Type Schemes for the Shallow Water Equations 认领
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作者 Christian Klingenberg Alexander Kurganov +1 位作者 Yongle Liu Markus Zenk 《数学研究通讯:英文版》 CSCD 2020年第3期247-271,共25页
We construct new HLL-type moving-water equilibria preserving upwind schemes for the one-dimensional Saint-Venant system of shallow water equations with nonflat bottom topography.The designed first-and secondorder sche... We construct new HLL-type moving-water equilibria preserving upwind schemes for the one-dimensional Saint-Venant system of shallow water equations with nonflat bottom topography.The designed first-and secondorder schemes are tested on a number of numerical examples,in which we verify the well-balanced property as well as the ability of the proposed schemes to accurately capture small perturbations of moving-water steady states. 展开更多
关键词 Shallow water equations Harten-Lax-Van Leer(HLL)scheme well-balanced method steady-state solutions(equilibria) moving-water and still-water equilibria
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文章速递Gray Water Measurement and Feasibility of Retrieval Using Innovative Technology and Application in Water Resources Management in Isfahan-Iran 认领
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作者 Safieh Javadinejad Rebwar Dara Forough Jafary 《地理研究(英文)》 2020年第2期11-19,共9页
Reuse of wastewater for agriculture and green spaces purposes is significant.A mean yearly precipitation in Esfahan is 150 mm.The drinking water and agriculture usually used underground resources in the city.Gray wate... Reuse of wastewater for agriculture and green spaces purposes is significant.A mean yearly precipitation in Esfahan is 150 mm.The drinking water and agriculture usually used underground resources in the city.Gray water recycling is known as a suitable option today.Delivering all the water requirements of a home from refined water rises the cost of water.Whereas the essential water quality for garden,toilet and irrigation is less than drinking water.Therefore,the aim of this study is to analyze the evaluation of gray water and estimate the amount of recycle gray water which can use for drinking water with innovation method in Esfahan region in Iran.Previous studies did not measure the value of recycling gray water with new method of waste water treatment that can use for drinking purpose.In this study,gray water in Esfahan city is measured and technical aspects of its recycling is examined.Because of the lack of referable guidelines and official technical reports,studies from other similar countries applied in this study and on the basis of which the amount of recoverable gray water was calculated.Evaluations indicates that the overall recovery of gray water in Esfahan saves nine million cubic meters of water.The price of the rial of this value established on water is 190 billion Rials.Given the lack of water sources in Esfahan,the recycle of gray water seems to be a good option,however more research is required to select a recovery strategy. 展开更多
关键词 Gray water Sustainable water management New technology Reuse of gray water
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文章速递Research on Ecological Water Cycle and Purification in Rural Landscape——Take Zhangjia Village Ecological Wastewater Treatment Project in Henan Province as an Example 认领
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作者 Mengmeng Li Mei Yang +1 位作者 Min Zhang Tao Xu 《环境科学与工程:A》 2020年第5期188-203,共16页
Rural landscape is not only a natural landscape,but also a cultural landscape.The improvement of rural environment in Lushi County is carried out under the background of“Building Beautiful Villages”.Through the plan... Rural landscape is not only a natural landscape,but also a cultural landscape.The improvement of rural environment in Lushi County is carried out under the background of“Building Beautiful Villages”.Through the plan of environmental improvement,the appearance of villages in rural areas will be significantly improved,and the gap between urban and rural areas will be shortened.This research addresses the problems of scarce water resources,imperfect rainwater collection facilities,and increased environmental pollution in rural areas,and explores a flexible,effective,and integrated landscape ecological water treatment system that integrates with natural ecosystems.The practice has shown that the flexible combination of different technical measures according to local conditions and the construction of ecological water self-circulation and self-purification systems can reduce maintenance costs and achieve sustainable landscape.The virtuous cycle of the revetment’s micro-ecology greatly improves the environmental carrying capacity of the landscape.Reasonable water management system is more flexible in dealing with unexpected problems.The thesis proposes landscape design strategies for water circulation and water purification in rural areas,and applies them to actual design cases.It attempts to introduce a combined treatment system to achieve a more diverse landscape concept and further explore the healthy and sustainable development of rural water environment. 展开更多
关键词 Landscape water ecological water cycle ecological water purification Zhangjia Village Henan Province
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舍得“水密码”对酿酒生产的影响 认领
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作者 杜德军 唐玉云 +3 位作者 谢铭 马杰 宋继恒 郭辉祥 《酿酒》 CAS 2020年第3期50-53,共4页
水源质量、取水方式、用水工艺在酿酒生产中都是影响酒质的重要因素。通过取用涪江优质水源经过深层地质过滤后的深井水,用于酿酒生产;在生产过程中精准控制用水技艺、升级水质,生产出优质大曲、基酒、原酒及最后的酒类产品。优质水源... 水源质量、取水方式、用水工艺在酿酒生产中都是影响酒质的重要因素。通过取用涪江优质水源经过深层地质过滤后的深井水,用于酿酒生产;在生产过程中精准控制用水技艺、升级水质,生产出优质大曲、基酒、原酒及最后的酒类产品。优质水源、高级沱泉、精湛水艺组成的“水密码”,是舍得生态酿酒的品质标杆关键因素之一。 展开更多
关键词 水源 取水方式 用水工艺 产品质量
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Effects of water application intensity of micro-sprinkler irrigation and soil salinity on environment of coastal saline soils 认领
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作者 Lin-lin Chu Yao-hu Kang Shu-qin Wan 《水科学与水工程:英文版》 EI CAS CSCD 2020年第2期116-123,共8页
To achieve the greatest leaching efficiency,water movement must occur under unsaturated flow conditions.Accordingly,the water application intensity of irrigation must be chosen carefully.The aim of this study was to e... To achieve the greatest leaching efficiency,water movement must occur under unsaturated flow conditions.Accordingly,the water application intensity of irrigation must be chosen carefully.The aim of this study was to evaluate the impact of the water application intensity of micro-sprinkler irrigation on coastal saline soil with different salt contents.To achieve this objective,a laboratory experiment was conducted with three soil salinity treatments(2.26,10.13,and 22.29 dS/m)and three water application intensity treatments(3.05,5.19,and 7.23 mm/h).The results showed that the effect of soil salinity on soil water content,electrical conductivity,and pH was significant,and the effect of the water application intensity was insignificant.High soil water content was present in the 40e60 cm profile in all soil salinity treatments,and the content was higher in the medium and high water application intensity treatments than in the low-intensity treatment.Significant salt leaching occurred in all treatments,and the effect was stronger in the high soil salinity treatment and medium water application intensity treatment.In the medium and high soil salinity treatments,pH exhibited a decreasing trend,with no trend change in the low soil salinity treatment,and the pH value was higher in the medium water application intensity treatment than in the other two treatments.These results indicated that the three intensities evaluated had no statistically different effect on the electrical conductivity of saturated soil-paste extracts(EC)in the upper 20 cm of the soil profile,and it would be better to maintain a lower value of the water application intensity. 展开更多
关键词 Soil water content SALINITY Micro-sprinkler irrigation Water application intensity Saline soil environment
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Ecological and Human Health Risk Assessment of Toxic Metals in Water, Sediment and Fish from Lower Usuma Dam, Abuja, Nigeria 认领
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作者 R. Wuana C. Ogbodo +1 位作者 A. U. Itodo I. S. Eneji 《地球科学和环境保护期刊(英文)》 2020年第5期82-106,共25页
The study assessed the levels of some toxic metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) with their potential ecological and human health risks in water, African Catfish (Clarias gariepinus), Tilapia (Oreochromis spilur... The study assessed the levels of some toxic metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) with their potential ecological and human health risks in water, African Catfish (Clarias gariepinus), Tilapia (Oreochromis spilurus niger) and sediment samples from the Lower Usuma dam FCT, Nigeria during two major seasons in a year (rainy and dry seasons). Toxic metal concentrations were determined using Atomic Absorption spectrophotometry (Cd, Cr, Cu, Ni, Pb and Zn) and Atomic Emission Spectrophotometry (for As and Hg), and the results obtained were compared with national and international standards. The ecological and human health risk indices of the toxic metals present in the samples from the Dam were evaluated and interpreted. Tilapia from the dam posed the highest but medium ecological and human health risk due to Pb concentration of up to 7.11 mg/kg;ecological risk index of 35.55 and hazard quotient of 50.78. Overall ecological and human health risks were low due to the low concentrations of other toxic metals determined. As, Cd, Cr, Cu, Hg, Ni and Zn concentrations were all below WHO limits in the LUD water;Ni and Pb were above limits in the African Catfish and Tilapia samples. The data obtained were analyzed using one-way analysis of variance (ANOVA) and significant differences accepted at p ≤ 0.05. There was no statistical difference in the concentrations of toxic metals in water but there was significant difference between the concentrations of toxic metals in the fish and sediment samples. Correlation was found to exist between toxic metals in the water, fish and sediment analyzed from the dam. The ecological and human health risks of toxic metals in Lower Usuma dam require regular checks and monitoring hence, it was recommended by the researcher, that this and similar research work be carried out annually by NESREA and also, as research work by other students of Environmental and Analytical chemistry. 展开更多
关键词 Toxic Metals AAS AES Concentration ECOLOGICAL RISK Human Health RISK LOWER Usuma DAM Contamination Factor Water SEDIMENT FISH
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Interfacial phenomena of water striders on water surfaces: a review from biology to biomechanics 认领
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作者 Jing-Ze Ma Hong-Yu Lu +1 位作者 Xiao-Song Li Yu Tian 《动物学研究》 SCIE CAS CSCD 2020年第3期231-246,共16页
Water striders have intrigued researchers for centuries from the viewpoints of biology to biomechanics. In this review, we introduce the basic theories and techniques of physics and force measurement for biomechanical... Water striders have intrigued researchers for centuries from the viewpoints of biology to biomechanics. In this review, we introduce the basic theories and techniques of physics and force measurement for biomechanical research into water striders. Morphological and behavioral traits of water striders are summarized and discussed from biomechanical perspectives, along with comparative study. This integrated review also highlights potential directions for studies on water-walking arthropods,which might inspire future biological and biomechanical research. 展开更多
关键词 Water strider Water repellency Surface tension Surface propulsion
Coupling analysis of social-economic water consumption and its effects on the arid environments in Xinjiang of China based on the water and ecological footprints 认领
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作者 ZHANG Pei DENG Mingjiang +5 位作者 LONG Aihua DENG Xiaoya WANG Hao HAI Yang WANG Jie LIU Yundong 《干旱区科学:英文版》 SCIE CSCD 2020年第1期73-89,共17页
In arid areas,ecological degradation aroused by over-exploitation of fresh water,expansion of artificial oasis and shrinkage of natural oasis,has drawn attention of many scholars and officials.The water and ecological... In arid areas,ecological degradation aroused by over-exploitation of fresh water,expansion of artificial oasis and shrinkage of natural oasis,has drawn attention of many scholars and officials.The water and ecological footprints can be used to quantitatively evaluate the water consumption of social-economic activities and their influence on the eco-environments.In addition,increase of the water footprint indicates the expansion of artificial oasis,and the influence on the natural oasis could be reflected by the variation of the ecological footprint.This study was conducted to answer a scientific question that what is the quantitative relationship between the expansion of the artificial oasis and the degradation of the natural oasis in the arid environments of Xinjiang,China.Thus,based on the social-economic data,water consumption data and meteorological data during 2001–2015,we calculated the water and ecological footprints to express the human-related pressure exerted on the water resources and arid environments in Xinjiang(including 14 prefectures and cities),and explore the relationship between the water and ecological footprints and its mechanism by using the coupling analysis and Granger causality test.The results show that both the water and ecological footprints of Xinjiang increased significantly during 2001–2015,and the increasing rate of the ecological footprint was much faster than that of the water footprint.The coupling degree between the water and ecological footprints was relatively high at the temporal scale and varied at the spatial scale.Among the 14 prefectures and cities examined in Xinjiang,the greater social-economic development(such as in Karamay and Urumqi)was associated with the lower coupling degree between the two footprints.Increases in the water footprint will cause the ecological footprint to increase,such that a 1-unit increase in the consumption of water resources would lead to 2–3 units of ecological degradation.The quantitative relationship between the increases of the wate 展开更多
关键词 WATER consumption ecological FOOTPRINT WATER FOOTPRINT GRANGER CAUSALITY test natural OASIS artificial OASIS Tarim River
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Effects of water application uniformity using a center pivot on winter wheat yield, water and nitrogen use efficiency in the North China Plain 认领
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作者 CAI Dong-yu YAN Hai-jun LI Lian-hao 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第9期2326-2339,共14页
In recent years, the use of fertigation technology with center pivot irrigation systems has increased rapidly in the North China Plain (NCP). The combined effects of water and nitrogen application uniformity on the gr... In recent years, the use of fertigation technology with center pivot irrigation systems has increased rapidly in the North China Plain (NCP). The combined effects of water and nitrogen application uniformity on the grain yield, water use efficiency (WUE) and nitrogen use efficiency (NUE) have become a research hotspot. In this study, a two-year field experiment was conducted during the winter wheat growing season in 2016–2018 to evaluate the water application uniformity of a center pivot with two low pressure sprinklers (the R3000 sprinklers were installed in the first span, the corresponding treatment was RS;the D3000 sprinklers were installed in the second span, the corresponding treatment was DS) and a P85A impact sprinkler as the end gun (the corresponding treatment was EG), and to analyze its effects on grain yield, WUE and NUE. The results showed that the water application uniformity coefficients of R3000, D3000 and P85A along the radial direction of the pivot (CUH) were 87.5, 79.5 and 65%, respectively. While the uniformity coefficients along the traveling direction of the pivot (CUC) were all higher than 85%. The effects of water application uniformity of the R3000 and D3000 sprinklers on grain yield were not significant (P>0.05);however, the average grain yield of EG was significantly lower (P<0.05) than those of RS and DS, by 9.4 and 11.1% during two growing seasons, respectively. The coefficients of variation (CV) of the grain yield had a negative correlation with the uniformity coefficient. The CV of WUE was more strongly affected by the water application uniformity, compared with the WUE value, among the three treatments. The NUE of RS was higher than those of DS and EG by about 6.1 and 4.8%, respectively, but there were no significant differences in NUE among the three treatments during the two growing seasons. Although the CUH of the D3000 sprinklers was lower than that of the R3000, it had only limited effects on the grain yield, WUE and NUE. However, the cost of D3000 sprinklers is lower than t 展开更多
关键词 center pivot low pressure sprinkler water application uniformity winter wheat water and nitrogen use efficiency
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Recent Progress of Atmospheric Water Harvesting Using Metal-Organic Frameworks 认领
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作者 PAN Tingting YANG Kaijie HAN Yu 《高等学校化学研究:英文版》 SCIE CAS CSCD 2020年第1期33-40,共8页
Atmospheric water harvesting based on vapor adsorption is a newly emerged and potential technology to supply portable water for arid areas.To efficiently harvest vapor from the air,sorbents are required to have consid... Atmospheric water harvesting based on vapor adsorption is a newly emerged and potential technology to supply portable water for arid areas.To efficiently harvest vapor from the air,sorbents are required to have conside-rable adsorption capacity,easy regeneration and high stability.With the advantages of porous structure,tunable pore size and tailorable hydrophilicity,metal-organic frameworks(MOFs)have demonstrated excellent performance in vapor adsorption and water generation.In this review,we first discuss the degradation mechanisms of MOFs exposed to water and summarize the structure-stability relationship;by centering on the adsorption isotherms,the connection between the structure of MOFs and the water adsorption property is illuminated;finally,some prospects are suggested in order to push forward the progress of this technology. 展开更多
关键词 Metal ORGANIC framework ATMOSPHERIC WATER HARVESTING Hydrolytic stability WATER ADSORPTION ISOTHERM
Residual oil evolution based on displacement characteristic curve 认领
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作者 Duanchuan Lyu Chengyan Lin +2 位作者 Lihua Ren Chunmei Dong Jinpeng Song 《矿业科学技术学报:英文版》 SCIE EI CSCD 2020年第3期337-343,共7页
The purpose of this study was to determine the displacement and dynamic distribution characteristics of the remaining oil in the two development stages of water flooding and subsequent alkaline surfactant polymer(ASP)... The purpose of this study was to determine the displacement and dynamic distribution characteristics of the remaining oil in the two development stages of water flooding and subsequent alkaline surfactant polymer(ASP) flooding. The well pattern types in the water and ASP flooding stages are a longdistance determinant well pattern and short-distance five-point well pattern, respectively. The type A displacement characteristic curve can be obtained using the production data, and the slope of the straight-line section of the curve can reflect the displacement strength of the oil displacement agent. A numerical simulation was carried out based on the geological model. The results revealed that the injected water advances steadily with a large-distance determinant water-flooding well pattern. The single-well water production rate increases monotonically during water flooding. There is a significant positive correlation between the cumulative water-oil ratio and the formation parameter. Differential seepage between the oil and water phases is the main factor causing residual oil formation after water flooding, while the residual oil is still relatively concentrated. The effect of the chemical oildisplacement agent on improving the oil-water two-phase seepage flow has distinct stages during ASP flooding. The remaining oil production is extremely sporadic after ASP flooding. 展开更多
关键词 Water flooding ASP flooding Water-drive characteristic curve Residue oil Thick oil layer
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Promoting the Construction of Beautiful and Rich China with the Theory of Soil and Water Ecology 认领
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作者 Fazheng SUN 《气象与环境研究:英文版》 CAS 2020年第2期20-24,共5页
Started from the problems and perplexities of ecological environment in China,the scientific principle and value of the theory of soil and water ecology are discussed. It is thought that the theory of soil and water e... Started from the problems and perplexities of ecological environment in China,the scientific principle and value of the theory of soil and water ecology are discussed. It is thought that the theory of soil and water ecology clarifies the complicated problems of ecological environment. Environmental pollution can be controlled,but it is only a matter of time and cost. Soil and water ecology is the root of ecological environment problems. The clean water and green mountain are destroyed,which cannot be restored. With the theory of soil and water ecology,the idea that clean water and green mountain are golden and silver mountains is read,as well as the way of turning clean water and green mountain into golden and silver mountains and its different impacts on eco-environment. The developed and underdeveloped areas should treat the idea that clean water and green mountain are golden and silver mountains. The application of the theory of soil and water ecology in soil and water conservation broadens the space of soil and water conservation,and it is necessary to establish a national commission for the conservation of soil and water ecology. The theory of soil and water ecology is the golden key to solve the problems of contemporary ecological environment and the theoretical basis for building a beautiful and rich China. 展开更多
关键词 Ecological environment SOIL and WATER ecology Clean WATER and green mountain GOLDEN and silver MOUNTAINS BEAUTIFUL and RICH
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水分对枣棉间作复合系统产量及水分生产率的影响 认领
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作者 田玉刚 李燕芳 +3 位作者 赵淑珍 汪志强 纪宇曦 胡守林 《现代农业科技》 2020年第11期8-10,13,共4页
为探明适宜于南疆枣棉间作复合系统合理的灌水量,设置4个水分梯度,采用随机区组试验设计,研究枣棉间作不同水分处理对枣棉间作复合系统产量及水分生产率的影响。结果表明,随着灌水量的增加,枣棉间作群体产量呈现先减小后增加再减小的趋... 为探明适宜于南疆枣棉间作复合系统合理的灌水量,设置4个水分梯度,采用随机区组试验设计,研究枣棉间作不同水分处理对枣棉间作复合系统产量及水分生产率的影响。结果表明,随着灌水量的增加,枣棉间作群体产量呈现先减小后增加再减小的趋势;灌水量5250 m^3/hm^2处理产量最高,为2828.9 kg/hm^2,与灌水量3750、4500、6000 m^3/hm^2处理产量差异显著;不同水分处理下的水分生产率有明显差异,依次为灌水量3750 m^3/hm^2>灌水量5250 m^3/hm^2>灌水量4500 m^3/hm^2>灌水量6000 m^3/hm^2。因此,枣棉间作最佳灌水量为5250 m^3/hm^2。 展开更多
关键词 枣棉间作 水分 产量 水分生产率
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Energy and Water Conservation Technology Analysis of Water Supply and Drainage of the Building 认领
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作者 Yisong Yin Xiaolong Ruan 《世界建筑(百图)》 2020年第4期22-25,共4页
At present,China’s social and economic development is faster and faster.At the same time,people pay more and more attention to the construction concept of energy and water conservation.We can see the popularization a... At present,China’s social and economic development is faster and faster.At the same time,people pay more and more attention to the construction concept of energy and water conservation.We can see the popularization and development of the concept of energy saving and water saving in every major field of our country,the same is true in the construction field.In order to effectively protect the ecological environment and maximize the use of limited resources,the energysaving and water-saving technology of the building,as well as water supply and drainage technology should be actively used.Based on this,this paper first analyzes the application significance of water supplydrainage and energy-water conservation technology in the construction field,analyzes the current situation of water supply and drainage in China,and proposes the application of water supply-drainage and energy-water conservation technology of the building for reference. 展开更多
关键词 Construction Engineering Water supply and drainage Energy and water conservation technology
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《老子》“玄”与“玄德”新释 认领
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作者 尚永亮 朱春洁 《复旦学报:社会科学版》 CSSCI 北大核心 2020年第1期40-47,共8页
"玄"与"玄德"是《老子》中非常重要的两个概念,历来解说者众,然多一间有隔。从文化发生学和五行说的角度看,所谓"玄德"即"水德",而"玄"除后起的玄妙诸义外,主要指水或水之特性:其黑... "玄"与"玄德"是《老子》中非常重要的两个概念,历来解说者众,然多一间有隔。从文化发生学和五行说的角度看,所谓"玄德"即"水德",而"玄"除后起的玄妙诸义外,主要指水或水之特性:其黑而兼赤之色给人幽昧深妙之感,其本身既为万物之始又兼具生生不息之性。在某种意义上可以说,"玄"与"玄德"就是以母体和女性生命力为旨归的"水德"哲学。与此相关,"玄牝"指深幽莫测可以容水之母体,"玄鉴"是践行"水德"的重要方式,"玄通""玄同"则成为"水德"在世间万物中的呈现状态。仔细辨析、认知这些概念及其关联,可以从本源处深化对老子哲学的理解。 展开更多
关键词 “玄” “玄德” 水德 母体
十六烷基三甲基氯化铵改性黏土固沙保水性能 认领
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作者 渠永平 张增志 《农业工程学报》 EI CAS CSCD 北大核心 2020年第13期109-115,共7页
为解决沙漠公路施工和养护中固沙难的问题,利用十六烷基三甲基氯化铵(Cetyltrimethyl Ammonium Chloride,CTAC)制备了一种改性黏土材料。研究了材料的力学性能、抗老化性能和保水性能,并利用X射线衍射仪、红外光谱分析仪和扫描电子显微... 为解决沙漠公路施工和养护中固沙难的问题,利用十六烷基三甲基氯化铵(Cetyltrimethyl Ammonium Chloride,CTAC)制备了一种改性黏土材料。研究了材料的力学性能、抗老化性能和保水性能,并利用X射线衍射仪、红外光谱分析仪和扫描电子显微镜对其固沙保水机理进行分析。结果表明:当CTAC与黏土的质量比为5:4时,固沙材料力学性能和耐老化性能较好,其透气保水性能较为均衡,草籽发芽率达到最高,为47%。微观分析表明:CTAC通过插层作用将松散的黏土颗粒连接,黏土间隙变为憎水性,水分运移阻力增大,因此改性黏土固沙保水性能较好。研究结果可为固沙材料的改进应用提供参考。 展开更多
关键词 固沙 水分 荒漠化 保水 十六烷基三甲基氯化铵 改性黏土
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Stable oxygen-hydrogen isotopes reveal water use strategies of Tamarix taklamakanensis in the Taklimakan Desert,China 认领
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作者 DONG Zhengwu LI Shengyu +3 位作者 ZHAO Ying LEI Jiaqiang WANG Yongdong LICongjuan 《干旱区科学:英文版》 SCIE CSCD 2020年第1期115-129,共15页
Tamarix taklamakanensis,a dominant species in the Taklimakan Desert of China,plays a crucial role in stabilizing sand dunes and maintaining regional ecosystem stability.This study aimed to determine the water use stra... Tamarix taklamakanensis,a dominant species in the Taklimakan Desert of China,plays a crucial role in stabilizing sand dunes and maintaining regional ecosystem stability.This study aimed to determine the water use strategies of T.taklamakanensis in the Taklimakan Desert under a falling groundwater depth.Four typical T.taklamakanensis nabkha habitats(sandy desert of Tazhong site,saline desert-alluvial plain of Qiemo site,desert-oasis ecotone of Qira site and desert-oasis ecotone of Aral site)were selected with different climate,soil,groundwater and plant cover conditions.Stable isotope values of hydrogen and oxygen were measured for plant xylem water,soil water(soil depths within 0–500 cm),snowmelt water and groundwater in the different habitats.Four potential water sources for T.taklamakanensis,defined as shallow,middle and deep soil water,as well as groundwater,were investigated using a Bayesian isotope mixing model.It was found that groundwater in the Taklimakan Desert was not completely recharged by precipitation,but through the river runoff from snowmelt water in the nearby mountain ranges.The surface soil water content was quickly depleted by strong evaporation,groundwater depth was relatively shallow and the height of T.taklamakanensis nabkha was relatively low,thus T.taklamakanensis primarily utilized the middle(23%±1%)and deep(31%±5%)soil water and groundwater(36%±2%)within the sandy desert habitat.T.taklamakanensis mainly used the deep soil water(55%±4%)and a small amount of groundwater(25%±2%)within the saline desert-alluvial plain habitat,where the soil water content was relatively high and the groundwater depth was shallow.In contrast,within the desert-oasis ecotone in the Qira and Aral sites,T.taklamakanensis primarily utilized the deep soil water(35%±1%and 38%±2%,respectively)and may also use groundwater because the height of T.taklamakanensis nabkha was relatively high in these habitats and the soil water content was relatively low,which is associated with the reduced groundwater depth due 展开更多
关键词 TAMARIX taklamakanensis WATER use STRATEGIES STABLE ISOTOPES Bayesian isotope mixing model deep soil WATER groundwater Taklimakan Desert
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Toward a socio-political approach to water management: successes and limitations of IWRM programs in rural northwestern China 认领
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作者 KuoRay MAO Qian ZHANG +1 位作者 Yongji XUE Nefratiri WEEKS 《地球科学前沿:英文版》 SCIE CAS CSCD 2020年第2期268-285,共18页
In rural north-western China,the tension between economic growth and ecological crises demonstrates the limitations of dominant top-down approaches to water management.In the 1990s,the Chinese government adopted the I... In rural north-western China,the tension between economic growth and ecological crises demonstrates the limitations of dominant top-down approaches to water management.In the 1990s,the Chinese government adopted the Integrated Water Resources Management(IWRM)approach to combat the degradation of water and ecological systems throughout its rural regions.While the approach has had some success at reducing desertification,water shortage,and ecological deterioration,there are important limitations and obstacles that continue to impede optimum outcomes in water management.As the current IWRM approach is instituted through a top-down centralized bureaucratic structure,it often fails to address the socio-political context in which water management is embedded and therefore lacks a complete treatment of how power is embedded in the bureaucracy and how it articulates through economic growth imperatives set by the Chinese state.The approach has relied on infrastructure heavy and technocratic solutions to govern water demand,which has worked to undermine the focus on integration and public participation.Finally,the historical process through which water management mechanisms have been instituted are fraught with bureaucratic fragmentation and processes of centralization that work against some of its primary goals such as reducing uncertainty and risk in water management systems.This article reveals the historical,social,political,and economic processes behind these shortcomings in water management in rural northwestern China by focusing on the limitations of a top-down approach that rely on infrastructure,technology,and quantification,and thereby advances a more holistic,socio-political perspective for water management that considers the state-society dynamics inherent in water governance in rural China. 展开更多
关键词 integrated water resources management topdown implementation inland river basin water rights China
Water Footprint in a Basket of Exportable Agricultural Products of San Juan Province 认领
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作者 Emilio Posleman Higinio Garcia 《农业科学与技术:A》 2020年第1期20-29,共10页
This paper calculates the water footprint(WF)and virtual water(VW)for a basket of exportable agricultural products of San Juan province.This basket includes:onion,white garlic and grapes for raisins.The VW of these th... This paper calculates the water footprint(WF)and virtual water(VW)for a basket of exportable agricultural products of San Juan province.This basket includes:onion,white garlic and grapes for raisins.The VW of these three productions is calculated and the consumption is evaluated in relation to the theoretical water reservoir capacity of the province.It is compared with results of other jobs.The methodology used is based on the WF assessment manual and on Food and Agriculture Organization’s(FAO’s)CROPWAT 8.0 model to identify the crops’water requirements and on the CIMWAT 2.0 climate database.Finally,recommendations are made for a more efficient use of water for agricultural production. 展开更多
关键词 Water footprint virtual water AGRICULTURE grapes for raisins
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