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基于BP-DEMATEL的山西省冬小麦水足迹影响因素识别
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作者 韩宇平 马伏枥 +3 位作者 贾冬冬 黄会平 张庚辰 苗浩东 《水资源保护》 EI CAS CSCD 北大核心 2024年第2期9-15,共7页
针对山西省冬小麦水足迹历史演变及关键影响因素识别问题,分析了1993—2021年山西省冬小麦水足迹历史演变规律,利用BP神经网络-决策实验室(BP-DEMATEL)模型对冬小麦水足迹演变的关键影响因素进行识别,将其分为驱动型因素及特征型因素,... 针对山西省冬小麦水足迹历史演变及关键影响因素识别问题,分析了1993—2021年山西省冬小麦水足迹历史演变规律,利用BP神经网络-决策实验室(BP-DEMATEL)模型对冬小麦水足迹演变的关键影响因素进行识别,将其分为驱动型因素及特征型因素,并揭示了影响因素之间的作用机制。结果表明:1993—2021年山西省冬小麦水足迹及单位水足迹均呈下降趋势;2021年山西省冬小麦总水足迹为27亿m^(3)(蓝水占比57%),单位水足迹为1 122 m^(3)/t,与前期高点相比分别下降38%(较1994年)和21%(较1993年);气温、相对湿度和灌溉面积为冬小麦水足迹演变的关键驱动型因素,化肥施用量和农业机械总动力为关键特征型因素。 展开更多
关键词 BP神经网络-决策实验室模型 水足迹 冬小麦 山西省
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Seepage effects of groundwater and its make-up water on triggering ground subsidence 被引量:3
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作者 Zhenhua Ouyang Meifeng Cai Changhong Li Mowen Xie 《Journal of University of Science and Technology Beijing》 CSCD 2006年第1期11-15,共5页
The functioning mechanism of groundwater and its make-up water in the process of ground subsidence was studied from such three aspects as osmotic corrasion, osmotic pressure effect and concretion effect, As to osmotic... The functioning mechanism of groundwater and its make-up water in the process of ground subsidence was studied from such three aspects as osmotic corrasion, osmotic pressure effect and concretion effect, As to osmotic corrasion, its forming conditions, mechanical mechanism and process were analyzed, As to osmotic pressure effect, it was mainly studied from hydrostatic pressurizing effect, sop softening effect and negative pressure sealing effect. Through concretion and saturation of soil, the factors of concretion settlement were analyzed. The results showed that both groundwater and its make-up water are important triggering factors to ground subsidence. 展开更多
关键词 GROUNDwater make-up water ground subsidence seepage effect
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基于NSGA-Ⅲ的区域水资源多目标优化配置方案决策
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作者 袁志朋 杨侃 +3 位作者 陈静 钱琳虹 李哲东 吴佳锋 《人民黄河》 CAS 北大核心 2024年第7期79-84,153,共7页
为了探究缺水地区如何发挥水资源优化配置综合效益,强化水资源管理,提出以社会、经济、生态为目标的区域水资源优化配置模型。结合水资源实际配置情况,应用第三代非支配排序遗传算法(NSGA-Ⅲ)求解配置模型并获得待选方案集,随后通过建... 为了探究缺水地区如何发挥水资源优化配置综合效益,强化水资源管理,提出以社会、经济、生态为目标的区域水资源优化配置模型。结合水资源实际配置情况,应用第三代非支配排序遗传算法(NSGA-Ⅲ)求解配置模型并获得待选方案集,随后通过建立博弈论-TOPSIS评价模型,对方案集进行筛选获得相对最佳方案。以忻州-阳泉供水区为研究对象,对来水频率为75%、50%、25%的水资源优化配置方案进行求解分析。结果表明:改进NSGA-Ⅲ算法和博弈论-TOPSIS评价模型在模型求解过程中具有较强的实用性,使得优选方案结果更为合理,相较其他方法具有明显优势;最后通过对不同配置方案分析可知,忻州-阳泉供水区实现可持续发展的关键在于不断提升水资源利用效率和努力实现水资源的可持续利用。 展开更多
关键词 水资源配置 多目标优化 NSGA-Ⅲ算法 TOPSIS法 方案决策
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基于群体决策熵优化-CRITIC算法评价灌溉水源适宜性
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作者 丁思羽 陈菁 +5 位作者 贺一凡 仲莉恩 李金刚 王收 颜爱忠 钟铭可 《节水灌溉》 北大核心 2024年第5期100-106,共7页
干旱半干旱地区缺乏针对性的灌溉水源适宜性评价方法,且评价方法适用性不强,指标较为单一,无法运用至多种水源,故以干旱半干旱地区为研究对象,探究能适用于不同灌溉水源适宜性的评价方法。综合考虑灌溉水源可供应量、灌溉水供应及时程... 干旱半干旱地区缺乏针对性的灌溉水源适宜性评价方法,且评价方法适用性不强,指标较为单一,无法运用至多种水源,故以干旱半干旱地区为研究对象,探究能适用于不同灌溉水源适宜性的评价方法。综合考虑灌溉水源可供应量、灌溉水供应及时程度、提水能耗费、灌溉水温等因素构建灌溉水源适宜性评价指标体系,引入群体决策熵优法-CRITIC算法确定评价指标的组合权重,以宁夏平罗县3种可利用的灌溉水源为典型案例,结合构建的评价指标体系及权重确定方法,采用TOPSIS法对3种不同水源4-9月的灌溉适宜性进行综合评价。平罗县黄河水与排水4-9月的贴近程度值皆大于0.31,均适宜灌溉。地下水4月的贴近程度值仅为0.2412,不适宜灌溉,但地下水5-8月的贴近程度值皆大于0.31,适宜灌溉,与宁夏银北灌区实际情况相符。构建的评价指标体系和引入的组合权重确定方法(群体决策熵优化-CRITIC算法)适用于干旱半干旱区的灌溉水源适宜性评价。 展开更多
关键词 灌溉水源适宜性 银北灌区 群体决策 熵优化 组合权重 指标体系
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基于NSGA-Ⅲ算法的长距离调水泵站多目标优化调度研究
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作者 王永康 吕谋 +1 位作者 李源 冯鹏 《水电能源科学》 北大核心 2024年第5期154-158,共5页
针对长距离调水泵站运行过程中水泵运行效率低、安全隐患较大等问题,以调水泵站运行电费最小、水泵平均效率最大、水泵流量平均偏离度最小、水泵平均启停频次最小为目标建立优化模型。以华东某沿海城市调水工程为例,采用第三代非支配排... 针对长距离调水泵站运行过程中水泵运行效率低、安全隐患较大等问题,以调水泵站运行电费最小、水泵平均效率最大、水泵流量平均偏离度最小、水泵平均启停频次最小为目标建立优化模型。以华东某沿海城市调水工程为例,采用第三代非支配排序遗传算法(NSGA-Ⅲ)求解优化模型,运用层次分析法与CRITIC法进行组合赋权,结合逼近理想解排序法(TOPSIS)进行方案优选。结果表明,相较于常规调度方案,优化调度方案中两泵站的运行电费和水泵流量平均偏离度均显著降低,水泵平均效率均显著提高,水泵平均启停频次均有所减少。表明在综合考虑泵站运行经济性的情况下,所建优化模型能够有效降低安全隐患。 展开更多
关键词 长距离调水泵站 NSGA-Ⅲ算法 多目标优化 多属性决策 优化调度
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Three-dimensional hydrodynamic model of Xiamen waters 被引量:5
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作者 WenShenghui CaiSong +1 位作者 TangJunjian CaiQifu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期151-170,共20页
A semi-implicit and Eulerian - Lagrangian finite difference method for three-dimensionalshallow flow has been extended to a more complete system of equations incorporating second-moment turbulence closure model and tr... A semi-implicit and Eulerian - Lagrangian finite difference method for three-dimensionalshallow flow has been extended to a more complete system of equations incorporating second-moment turbulence closure model and transport equations of salinity and temperature. The simulation for flooding and drying of mudflats has been improved. The model is applied to Xiamen waters. Based on extensive survey data, water level elevation, temperature and salinity field along the eastern open boundary and at the Jiulong River inlets and runoffs are analyzed, specified and calibrated. The computed results show good agreement with the measured data, reproduce flooding, emergence of large and complex mudflat region. 展开更多
关键词 Semi-implicit finite difference scheme Eulerian - Lagrangian approach three-dimensional shallow water flow Xiamen waters
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The diffusive fluxes of inorganic nitrogen across the intertidal sediment-water interface of the Changjiang Estuary in China 被引量:5
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作者 HOU Lijun LIU Min +3 位作者 XU Shiyuan LU Jianjian OU Dongni YU Jie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第3期48-57,共10页
Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitu... Ammonium and nitrate concentrations were analyzed in near-bottom water and pore water collected from ten stations of the intertidal flat of the Changjiang Estuary during April, July, November and February. The magnitudes of the benthic exchange fluxes were determined on the basis of concentration gradients of ammonium and nitrate at the near-bottom water and interstitial water interface in combination with calculations of a modified Fick' s first law. Ammonium fluxes varied from - 5.05 to 1.43 μg/( cm^2·d) and were greatly regulated by the production of ammonium in surface sediments, while nitrate fluxes ranged from - 0. 38 to 1.36 μg/ ( cm^2·d) and were dominated by nitrate concentrations in the tidal water. It was found that ammonium was mainly released from sediments into water columns at most of stations whereas nitrate was mostly diffused from overlying waters to intertidal sediments. In total, 823.75 t/a ammonium-N was passed from intertidal sediments to water while about 521.90 t/a nitrate-N was removed from overlying waters to intertidal sediments. This suggests that intertidal sediments had the significant influence on modulating inorganic nitrogen in the tidal water. 展开更多
关键词 AMMONIUM NITRATE sediment - water interface intertidal flat Changjiang Estuary
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Using irrigation intervals to optimize water-use efficiency and maize yield in Xinjiang,northwest China 被引量:7
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作者 Guoqiang Zhang Dongping Shen +10 位作者 Bo Ming Ruizhi Xie Xiuliang Jin Chaowei Liu Peng Hou Jun Xue Jianglu Chen Wanxu Zhang Wanmao Liu Keru Wang Shaokun Li 《The Crop Journal》 SCIE CAS CSCD 2019年第3期322-334,共13页
Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yiel... Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation. 展开更多
关键词 Irrigation frequency Soil moisture MAIZE High yield(>15 Mg ha^(-1)) water use efficiency
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Layer regrouping for water-flooded commingled reservoirs at a high water-cut stage 被引量:2
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作者 Chuan-Zhi Cui Jian-Peng Xu +3 位作者 Duan-Ping Wang Zhi-Hong Liu Ying-song Huang Zheng-Ling Geng 《Petroleum Science》 SCIE CAS CSCD 2016年第2期272-279,共8页
Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to impro... Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to improve oil recovery for high water-cut multilayered reservoirs. Dif- ferent regroup scenarios may lead to different production performances. Based on unstable oil-water flow theory, a multilayer commingled reservoir simulator is established by modifying the production split method. Taking into account the differences of layer properties, including per- meability, oil viscosity, and remaining oil saturation, the pseudo flow resistance contrast is proposed to serve as a characteristic index of layer regrouping for high water-cut multilayered reservoirs. The production indices of multi- layered reservoirs with different pseudo flow resistances are predicted with the established model in which the data are taken from the Shengtuo Oilfield. Simulation results show that the pseudo flow resistance contrast should be less than 4 when the layer regrouping is implemented. The K-means clustering method, which is based on the objec- tive function, is used to automatically carry out the layer regrouping process according to pseudo flow resistances. The research result is applied to the IV-VI sand groups of the second member of the Shahejie Formation in the Shengtuo Oilfield, a favorable development performance is obtained, and the oil recovery is enhanced by 6.08 %. 展开更多
关键词 water-flooded reservoirs Layer regrouping.Flow resistance - High water cut Reservoir simulation
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The Coupling Coordination Evolution Research of Economy - Ecology - Society System in Xinjiang:Based on the Interaction Perspective of Water Resources 被引量:1
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作者 Chen Junke Li Hong +1 位作者 Wang Xibo Ma Yongren 《Meteorological and Environmental Research》 CAS 2017年第5期73-77,共5页
Under the water resources perspective,coupling coordination of economy-ecology-society system in Xinjiang was taken as the research object. By building the coupling evaluation index system of the water resources-econo... Under the water resources perspective,coupling coordination of economy-ecology-society system in Xinjiang was taken as the research object. By building the coupling evaluation index system of the water resources-economy-ecology-society system,quantitative evaluation and analysis of the coupling coordination of the water resources-economy-ecology-society system from 2001 to 2014 were conducted. The results showed that benefit indexes of economic system and social system grew rapidly,while benefit indexes of water resources system and ecosystem fluctuated smoothly from 2001 to 2014; coupling state of the whole system was at rival stage,and coupling coordination was reluctant coordination type,and the coupling index was slightly higher than the coupling coordination index. Moreover,it showed that the more the coupling systems,the lower indices of coupling and the coupling coordination. 展开更多
关键词 water resources - ECONOMY - ECOLOGY - SOCIETY SYSTEM COUPLING coordination Evolution XINJIANG
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Effects of Different NH_4^+/NO_3^- Ratio and Water Condition on Physiological Characteristics of Rice Seedlings
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作者 Haimei WU Xiaoyuan CHEN +1 位作者 Yupeng ZHANG Fujie WU 《Agricultural Science & Technology》 CAS 2017年第10期1908-1911,1924,共5页
[Objective] This study aimed to further explore the dynamics of related physiological indexes of rice seedlings under different NH4+ /NO3- ratio and different water condition. [Method] Under the hydroponic condition ... [Objective] This study aimed to further explore the dynamics of related physiological indexes of rice seedlings under different NH4+ /NO3- ratio and different water condition. [Method] Under the hydroponic condition in laboratory, 3 NH4+/NO3- ratios (0/100, 50/50 and 100/0) and 2 water conditions (+PEG,-PEG) were designed for Fengliangyou 7203. [Result] The root-canopy ratio of rice seedlings increased under any of the NH4+/NO3- ratios and water conditions. Under water stress, the root-canopy ratio of rice seedlings changed most greatly at the NH4+/NO3- ratio of 0/ 100; the overall water potential of rice seedlings reached the lowest at the NH4+/ NO3- ratio of 100/0; and the changes of water potential and xylem flow pH were relatively stable at the NH4+/NO3- ratio of 50/50. Under the condition of no water stress, the growth of rice seedlings was best at the NH4+/NO3- ratio of 50/50, followed by the NH4+/NO3- ratios of 0/100 and 100/0. [Conclusion] This study will pro- vide a basis for understanding the relationship between water potential and xylem flow. 展开更多
关键词 Rice NH4+/NO3- ratio water stress water potential Root-canopy ratio
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Lithium Behavior in Salt-water System Explored by Molecular Dynamics Simulation
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作者 MA Yanfang LIU Jianchuan +1 位作者 LI Kanshe ZHANG Zhihong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第6期1016-1020,共5页
The molecular dynamics simulation method was adopted to study the transient characteristics of Li^+,CO3^2-,and SO4^2- in Na^+,K^+,Li^+,Cl^-,and SO4^2-/H2O system.The composition of Na^+,K^+,Li^+,Cl^-,SO4^2- and CO3^2-... The molecular dynamics simulation method was adopted to study the transient characteristics of Li^+,CO3^2-,and SO4^2- in Na^+,K^+,Li^+,Cl^-,and SO4^2-/H2O system.The composition of Na^+,K^+,Li^+,Cl^-,SO4^2- and CO3^2- was selected to optimize the initial structural model and conduct dynamic simulation.The mean azimuth shift and diffusion coefficient of Li^+,CO3^2-,and SO4^2- in the system,the radial distribution function and potential energy between Li^+ and -OW,SO4^2- and -OW as well as CO3^2- and -OW,and the dielectric constant of hydrogen bond were expounded and analyzed.At the same time,the Li enrichment behavior in the evaporation process of salt lake brine was analyzed based on the simulated data.The results show that the simulation results are in good agreement with the experimental values,which verifies that,compared with other ions,the crystallization of Li^+ and SO4^2- occurs earlier after reaching saturation. 展开更多
关键词 salt lakes Li^+ CO3^2- SO4^2- MD salt water system
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Determination of 16 Species of OCPs in Water by Liquid-liquid Extraction-GC
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作者 Li Ting Zhu Weiping +1 位作者 Xu Xiuyan Yang Hui 《Meteorological and Environmental Research》 CAS 2014年第1期55-58,共4页
[Objective] The research aimed to study the determination of 16 kinds of OCPs in water by liquid-liquid extraction -GC. [Method] The new method for determining 16 kinds of OCPs in water by liquid-liquid extraction -GC... [Objective] The research aimed to study the determination of 16 kinds of OCPs in water by liquid-liquid extraction -GC. [Method] The new method for determining 16 kinds of OCPs in water by liquid-liquid extraction -GC was established, and the influencing factors such as nitrogen pressure and water bath temperature were discussed. [ Result] Detection limit of the method was from 3.2 to 14.1 ng/L, the relative standard deviation was between 4.0% and 9.6%, and the average recovery ranged from 80.8% to 106.0%. By optimizing nitrogen pressure and water bath temperature in the sample pretreatment process, when nitrogen pressure was +0.087 kPa, and water bath temperature was ±36 ℃, recovery effect of this method was better. [ Conclusion] The determination method had accurate qualitative and quantitative results, and met detection requirement of 16 kinds of OCPs in water. 展开更多
关键词 Liquid-liquid extraction - GC OCPS Nitrogen pressure water bath temperature China
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Preliminary Study on Water Demand Law of 1-0 Rooted Cuttings of Populus szechuanica
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作者 Dabuqiong Haoyu WANG +2 位作者 Huanhuan XIE Zhen XING Yanhui YE 《Meteorological and Environmental Research》 CAS 2021年第4期39-42,共4页
In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and ... In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and the law of water demand of P.szechuanica was grasped.In this paper,potted seedlings of 1-0 rooted cuttings of P.szechuanica were taken as research objects,and change situation of water consumption under different water control gradients was measured regularly by using weighing method,further analyzing dynamic change of water consumption of P.szechuanica and revealing water demand law of 1-0 rooted cuttings of P.szechuanica.The results showed that total change of water consumption of 1-0 rooted cuttings of P.szechuanica had"slow-fast-slow-fast"double-peak trend in the growth period of the current year,and corresponded with univariate linear relation(R^(2)=0.7137),with significant difference.In whole growth period,water consumption in August was the highest,which was 2.7 times of that in June and July and 1.5 times of that after September.In different water control treatments,the dynamic changes of daily and monthly water consumption were significantly different.In seven water control treatments,monthly water consumption was between(6315.95±1690.70)and(10105.28±3065.30)g/month,and mean was(8211.07±2308.23)g/month.With intensification of water control treatment,water consumption increased,but there was no seedling death due to water shortage.P.szechuanica has great plasticity in water demand,and can survive in both arid and humid environments.Meanwhile,it is revealed that P.szechuanica is the most widely distributed tree species in the region. 展开更多
关键词 Populus szechuanica 1-0 rooted cuttings water consumption water demand law
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2015 IWA Alternative Water Resources Conference Nanjing,China(May 26-28,2015)
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《Water Science and Engineering》 EI CAS CSCD 2015年第2期174-174,共1页
The IWA Alternative Water Resources(AWR)Conference is organized by the International Water Association,Hohai University,the IWA China Chapter of the AWR Cluster,and the Seawater Desalination and AWR Utilization Rese... The IWA Alternative Water Resources(AWR)Conference is organized by the International Water Association,Hohai University,the IWA China Chapter of the AWR Cluster,and the Seawater Desalination and AWR Utilization Research Center of Hohai University. 展开更多
关键词 IWA Alternative water Resources Conference Nanjing China May 26-28 2015
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Water-Deficit Response Is Not Affected by Glutathione Deficiency in Arabidopsis thaliana pad2-1 Plants
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作者 Tana Jubany-Marí Seán Meehan +1 位作者 Marta López-Carbonell Leonor Alegre 《American Journal of Plant Sciences》 2016年第14期2020-2037,共18页
Changes in glutathione and ascorbate content, hydrogen peroxide and abscisic acid were studied in developing leaves in wild-type (Col-0) and glutathione-deficient mutant pad2-1 lines of Arabidopsis thaliana over a tim... Changes in glutathione and ascorbate content, hydrogen peroxide and abscisic acid were studied in developing leaves in wild-type (Col-0) and glutathione-deficient mutant pad2-1 lines of Arabidopsis thaliana over a time period of 9 days of drought followed by re-watering. Glutathione deficient mutant (pad2-1) presents mechanisms of acclimation to water stress through the reduction of plant biomass and increase in endogenous concentrations of ascorbate and glutathione. These acclimation responses to stress appeared along with the first symptoms of stress and we suggest here that they are regulated by ABA and H<sub>2</sub>O<sub>2</sub>. Normally, wild type plants under conditions of stress require an initial response phase in which a decrease in antioxidants is observed before reaching acclimation through the increase in levels of antioxidants. pad2-1 is more sensitive to stress and reacts to it;however, it did not suffer more oxidative stress than Col-0 plants, even though pad2-1 had higher levels of endogenous H<sub>2</sub>O<sub>2</sub> relative to wild-type. In both water stressed Col-0 and pad2-1 plants increases in ABA were observed, however, more sharply in wild-type stressed plants. Low levels of glutathione together with high levels of H<sub>2</sub>O<sub>2</sub> may regulate endogenous ABA concentrations and could be related to the slow growth rates which were observed during the experiment. The results highlighted the double function of glutathione as an antioxidant and signal molecule and also, the different response patterns of wild-type and pad2-1 when faced with drought stress. The results bring new insights to the responses of pad2-1 under conditions of water stress. 展开更多
关键词 Abscisic Acid ANTIOXIDANTS Growth Hydrogen Peroxide pad2-1 water Stress
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Water and nitrogen transport characteristics of single-line interference infiltration under film hole irrigation with muddy water and fertilizer
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作者 JIANG Ruirui FEI Liangjun KANG Shouxuan 《排灌机械工程学报》 CSCD 北大核心 2022年第5期496-503,共8页
Based on the experimental data,this study investigated the effect of sand content of muddy water on water and nitrogen transport characteristics of the single-line interference infiltration under film hole irrigation ... Based on the experimental data,this study investigated the effect of sand content of muddy water on water and nitrogen transport characteristics of the single-line interference infiltration under film hole irrigation with muddy water and fertilizer.The relationship between the single-line interference infiltration parameters,the sand content,the wetting front movement distances,and the sand content were all established.The model of the cumulative infiltration volume of per unit film pore area,the vertical and horizontal wetting front movement distance of the free surface,and the wetting front movement distance of the interference center with sand content and infiltration time were proposed.Reveal the law of the change of soil water content and the distribution of NO_(3)^(-)-N content based on different muddy water sand content.The results indicate that at the same infiltration time,as the muddy water sand content increases,the cumulative infiltration volume per unit pore area decreases.The infiltration index of the free infiltration and the single-line interference vary little when the sand content increases,mainly are around 0.64 and 0.58.The relationship between infiltration parameters a,b and the sand content is linear function.At the same location,the more the sand content,the smaller the wetting front movement distance in free surface and the single-line interference surface,the less the NO_(3)^(-)-N content. 展开更多
关键词 film hole irrigation single-line interference infiltration muddy water FERTILIZER sand content NO_(3)^(-)-N content
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Isobaric Vapor–Liquid Equilibrium for tert-Butyl Alcohol + Water + Propane-1,3-Diol + 1-Ethyl-3-Methylimidazolium Chloride at 101.3 kPa
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作者 Xianbao Cui Qinglong Cheng +5 位作者 Haofei Liu Lexing Xue Jinbo Zhou Ying Zhang Tianyang Feng Kai Zhang 《Transactions of Tianjin University》 EI CAS 2018年第5期424-433,共10页
In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobari... In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobaric vapor–liquid equilibrium(VLE) for the quaternary system TBA + water + propane-1,3-diol + [emim]Cl at 101.3 kPa, and found the VLE data to be well correlated with the nonrandom two-liquid model. These results show that the mixed solvent of propane-1,3-diol + [emim]Cl can increase the relative volatility of TBA to water and break the azeotropic point. We found no notable synergetic effect between them, and observed that the liquid mixed solvent of propane-1,3-diol and [emim]Cl had lower viscosity than [emim]Cl, which makes it a promising entrainer for separating the TBA + water azeotrope in industrial applications. 展开更多
关键词 tert-Butyl alcohol·water·Propane-1-3-diol·1-Ethyl-3-methylimidazolium chloride·Vapor–liquid EQUILIBRIUM
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A STUDY ON DECISION-MAKING OF ENVIRONMENTAL IMPACTS FOR REGIONAL WATER RESOURCES DEVELOPMENT
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作者 Guo Huaicheng Guan Boren(Center of Environmental Sciences, Peking University, Beijing 100871 People’s Repubic of China)Li Lijuan(Institute of Geography, CAS, Beijing 100101 People’s Repubic Of China) 《Journal of Geographical Sciences》 SCIE CSCD 1994年第Z2期69-76,共8页
On the basis of overall analysis, this Paper, taking Beijing-Tianjin-Tangshan region as an example, tries to find out main environmental problems caused by water resources development and to discuss the mitigaive meas... On the basis of overall analysis, this Paper, taking Beijing-Tianjin-Tangshan region as an example, tries to find out main environmental problems caused by water resources development and to discuss the mitigaive measures of the environmental impacts. The Paper, by means of Analytical Hierarchy Process (AHP, builds a multiple-hierarchy decision-making model including godl, water resources, environmental impact factors and mitigative measures. This study is very significant for alleviating and solving the problems of water resources-environmental system in the region. 展开更多
关键词 Beijing-Tianjin-Tangshan region water resourcesenvironmental system Analytical Hierarchy Process multiplehierarchy decision-making model
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Analysis on the Water-making Art of Islamic Garden
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作者 FANG Chenyu 《Journal of Landscape Research》 2020年第1期85-87,共3页
The climate in Islamic areas is hot and dry,and water is the most important element in Islamic gardens.The waterscape of Islamic gardens affects the layout of the whole courtyard,and the water-making art of Islamic ga... The climate in Islamic areas is hot and dry,and water is the most important element in Islamic gardens.The waterscape of Islamic gardens affects the layout of the whole courtyard,and the water-making art of Islamic gardens embodies the wisdom of the Arab nation.Through the analysis of the waterscape design of Islamic gardens,this study combed the design methods contained in the water-making art of Islamic gardens from the four aspects of water source,waterscape plane design,vertical design and decoration,in order to provide ideas for more efficient water landscape design in the garden landscape design. 展开更多
关键词 Islamic garden water-making waterscape design
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