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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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Internal structures and high-velocity frictional properties of Longmenshan fault zone at Shenxigou activated during the 2008 Wenchuan earthquake 被引量:3
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作者 Yu Wang Shengli Ma +7 位作者 Toshihiko Shimamoto Lu Yao Jianye Chen Xiaosong Yang Honglin He Jiaxiang Dang Linfeng Hou Tetsuhiro Togo 《Earthquake Science》 2014年第5期499-528,共30页
This paper reports internal structures of a wide fault zone at Shenxigou,Dujiangyan,Sichuan province,China,and high-velocity frictional properties of the fault gouge collected near the coseismic slip zone during the 2... This paper reports internal structures of a wide fault zone at Shenxigou,Dujiangyan,Sichuan province,China,and high-velocity frictional properties of the fault gouge collected near the coseismic slip zone during the 2008 Wenchuan earthquake.Vertical offset and horizontal displacement at the trench site were 2.8 m(NW side up)and 4.8 m(right-lateral),respectively.The fault zone formed in Triassic sandstone,siltstone,and shale about 500 m away from the Yingxiu-Beichuan fault,a major fault in the Longmenshan fault system.A trench survey across the coseismic fault,and observations of outcrops and drill cores down to a depth of 57 m revealed that the fault zone consists of fault gouge and fault breccia of about0.5 and 250-300 m in widths,respectively,and that the fault strikes N62°E and dips 68° to NW.Quaternary conglomerates were recovered beneath the fault in the drilling,so that the fault moved at least 55 m along the coseismic slip zone,experiencing about 18 events of similar sizes.The fault core is composed of grayish gouge(GG) and blackish gouge(BG) with very complex slip-zone structures.BG contains low-crystalline graphite of about 30 %.High-velocity friction experiments were conducted at normal stresses of 0.6-2.1 MPa and slip rates of 0.1-2.1 m/s.Both GG and BG exhibit dramatic slip weakening at constant high slip rates that can be described as an exponential decay from peak friction coefficient lpto steadystate friction coefficient lssover a slip-weakening distance Dc.Deformation of GG and BG is characterized by overlapped slip-zone structures and development of sharp slickenside surfaces,respectively.Comparison of our data with those reported for other outcrops indicates that the high-velocity frictional properties of the Longmenshan fault zones are quite uniform and the high-velocity weakening must have promoted dynamic rupture propagation during the Wenchuan earthquake. 展开更多
关键词 Wenchuan earthquake - Longmenshan faultsystem - Shenxigou fault zone Fault zone structures High-velocity friction
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基于FCM-GA灌溉供水管网减压阀布设优化 被引量:2
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作者 常子峰 李红艳 +3 位作者 史文韬 张峰 崔佳丽 毛立波 《节水灌溉》 北大核心 2024年第5期38-45,共8页
为探究灌溉供水管网中存在的漏损过高以及局部压力过大的问题,提出了一种基于FCM-GA的供水管网减压阀布设优化方法,该方法借助MATLAB、EPANET、MATLAB-EPANET-Toolkit以及PlatEMO平台等工具,对西班牙的BIN管网进行分区布置减压阀并优化... 为探究灌溉供水管网中存在的漏损过高以及局部压力过大的问题,提出了一种基于FCM-GA的供水管网减压阀布设优化方法,该方法借助MATLAB、EPANET、MATLAB-EPANET-Toolkit以及PlatEMO平台等工具,对西班牙的BIN管网进行分区布置减压阀并优化阀后压力,以不同分区方案的成本与降漏效果为控制指标,筛选出最优方案。结果显示:最优方案(分5个区)将整个管网的漏损率降低至7.45%,相较初始管网降低了20.04%,降低的漏损费用可达114€/d,在减压阀服务年限内可收回成本并达到盈利,并实现对整个管网系统的压力管理,提高了管网的稳定性和可靠性,有利于减少管网事故发生。因此,基于FCM-GA的灌溉供水管网减压阀布设优化是一种安全、低成本和高效益的降漏与控压方法,在有效降低灌溉用水费用的同时,可更好地实现节水灌溉。 展开更多
关键词 灌溉供水管网 FCM-GA算法 供水管网分区 漏损控制 减压阀布设优化 压力管理
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Stem flow of seed-maize under alternate furrow irrigation and double-row ridge planting in an arid region of Northwest China 被引量:3
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作者 BO Xiao-dong DU Tai-sheng +2 位作者 DING Ri-sheng TONG Ling LI Si-en 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第7期1434-1445,共12页
Maize is widely planted throughout the world and has the highest yield of all the cereal crops. The arid region of North- west China has become the largest base for seed-maize production, but water shortage is the bot... Maize is widely planted throughout the world and has the highest yield of all the cereal crops. The arid region of North- west China has become the largest base for seed-maize production, but water shortage is the bottleneck for its long-term sustainability. Investigating the transpiration of seed-maize plants will offer valuable information for suitable planting and irrigation strategies in this arid area. In this study, stem flow was measured using a heat balance method under alternate furrow irrigation and double-row ridge planting. Meteorological factors, soil water content (e), soil temperature (Ts) and leaf area (LA) were also monitored during 2012 and 2013. The diurnal stem flow and seasonal dynamics of maize plants in the zones of south side female parent (SFP), north side female parent (NFP) and male parent (MP) were investigated. The order of stem flow rate was: SFP〉MP〉NFP. The relationships between stem flow and influential factors during three growth stages at different time scales were analyzed. On an hourly scale, solar radiation (Rs) was the main driving factor of stem flow. The influence of air temperature (Ta) during the maturity stage was significantly higher than in other periods. On a daily scale, Rs was the main driving factor of stem flow during the heading stage. During the filling growth stage, the main driving factor of NFP and MP stem flow was RH and Ts, respectively. However, during the maturity stage, the environ- mental factors had no significant influence on seed-maize stem flow. For different seed-maize plants, the main influential factors were different in each of the three growing seasons. Therefore, we identified them to accurately model the FP and MP stem flow and applied precision irrigation under alternate partial root-zone furrow irrigation to analyze major factors affecting stem flow in different scales. 展开更多
关键词 stem flow alternate partial root-zone furrow irrigation double-row ridge planting seed-maize
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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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North slope transition zone of Songnan-Baodao sag in Qiongdongnan Basin and its control on medium and large gas fields,South China Sea
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作者 XU Changgui YOU Li 《Petroleum Exploration and Development》 CSCD 2022年第6期1229-1242,共14页
Based on analysis of newly collected 3D seismic and drilled well data,the geological structure and fault system of Baodao sag have been systematically examined to figure out characteristics of the transition fault ter... Based on analysis of newly collected 3D seismic and drilled well data,the geological structure and fault system of Baodao sag have been systematically examined to figure out characteristics of the transition fault terrace belt and its control on the formation of natural gas reservoirs.The research results show that the Baodao sag has the northern fault terrace belt,central depression belt and southern slope belt developed,among them,the northern fault terrace belt consists of multiple transition fault terrace belts such as Baodao B,A and C from west to east which control the source rocks,traps,reservoirs,oil and gas migration and hydrocarbon enrichment in the Baodao sag.The activity of the main fault of the transition belt in the sedimentary period of Yacheng Formation in the Early Oligocene controlled the hydrocarbon generation kitchen and hydrocarbon generation potential.From west to east,getting closer to the provenance,the transition belt increased in activity strength,thickness of source rock and scale of delta,and had multiple hydrocarbon generation depressions developed.The main fault had local compression under the background of tension and torsion,giving rise to composite traps under the background of large nose structure,and the Baodao A and Baodao C traps to the east are larger than Baodao B trap.Multiple fault terraces controlled the material source input from the uplift area to form large delta sand bodies,and the synthetic transition belt of the west and middle sections and the gentle slope of the east section of the F12 fault in the Baodao A transition belt controlled the input of two major material sources,giving rise to a number of delta lobes in the west and east branches.The large structural ridge formed under the control of the main fault close to the hydrocarbon generation center allows efficient migration and accumulation of oil and gas.The combination mode and active time of the main faults matched well with the natural gas charging period,resulting in the hydrocarbon gas enrichment.Baodao A transition belt is adjacent to Baodao 27,25 and 21 lows,where large braided river delta deposits supplied by Shenhu uplift provenance develop,and it is characterized by large structural ridges allowing high efficient hydrocarbon accumulation,parallel combination of main faults and early cessation of faulting activity,so it is a favorable area for hydrocarbon gas accumulation.Thick high-quality gas reservoirs have been revealed through drilling,leading to the discovery of the first large-scale gas field in Baodo 21-1 of Baodao sag.This discovery also confirms that the north transition zone of Songnan-Baodao sag has good reservoir forming conditions,and the transition fault terrace belt has great exploration potential eastward. 展开更多
关键词 Qiongdongnan Basin Songnan-Baodao sag fault transition zone PaleogeneBaodo 21-1 medium and large gas fields large structural ridge composite trap hydrocarbon gas
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A multi-mineral model for predicting petrophysical properties of complex metamorphic reservoirs:Case study of the Bozhong Depression,Bohai Sea
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作者 Guoqiang Zhang Zhongjian Tan +5 位作者 Guibin Zhang Dong Li Chenchen Liu Zhang Zhang Jun Cao Xin Lei 《Energy Geoscience》 EI 2024年第3期66-76,共11页
Interpreting reservoir properties through log data and logging responses in complex strata is critical for efficient petroleum exploitation,particularly for metamorphic rocks.However,the unsatisfactory accuracy of suc... Interpreting reservoir properties through log data and logging responses in complex strata is critical for efficient petroleum exploitation,particularly for metamorphic rocks.However,the unsatisfactory accuracy of such interpretations in complex reservoirs has hindered their widespread application,resulting in severe inconvenience.In this study,we proposed a multi-mineral model based on the least-square method and an optimal principle to interpret the logging responses and petrophysical properties of complex hydrocarbon reservoirs.We began by selecting the main minerals based on a comprehensive analysis of log data,X-ray diffraction,petrographic thin sections and scanning electron microscopy(SEM)for three wells in the Bozhong 19-6 structural zone.In combination of the physical properties of these minerals with logging responses,we constructed the multi-mineral model,which can predict the log curves,petrophysical properties and mineral profile.The predicted and measured log data are evaluated using a weighted average error,which shows that the multi-mineral model has satisfactory prediction performance with errors below 11%in most intervals.Finally,we apply the model to a new well“x”in the Bozhong 19-6 structural zone,and the predicted logging responses match well with measured data with the weighted average error below 11.8%for most intervals.Moreover,the lithology is dominated by plagioclase,K-feldspar,and quartz as shown by the mineral profile,which correlates with the lithology of the Archean metamorphic rocks in this region.It is concluded that the multi-mineral model presented in this study provides reasonable methods for interpreting log data in complex metamorphic hydrocarbon reservoirs and could assist in efficient development in the future. 展开更多
关键词 Logging interpretation Metamorphic rock Buried hill reservoir Petrophysical property prediction Bozhong 19-6 structural zone
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再生水分根交替滴灌对马铃薯根-土系统环境因子的影响研究 被引量:11
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作者 乔冬梅 齐学斌 +5 位作者 樊向阳 李平 胡超 樊涛 黄仲冬 赵志娟 《农业环境科学学报》 CAS CSCD 北大核心 2009年第11期2359-2367,共9页
分根交替(PRD)滴灌技术是很有节水潜力的灌水技术。利用再生水,采用分根交替滴灌技术对马铃薯根长密度、根重密度及土壤水盐的空间分布影响进行了研究。结果表明,马铃薯根系主要分布在0-60 cm的土层内,以植株为中心,呈放射状沿不同方... 分根交替(PRD)滴灌技术是很有节水潜力的灌水技术。利用再生水,采用分根交替滴灌技术对马铃薯根长密度、根重密度及土壤水盐的空间分布影响进行了研究。结果表明,马铃薯根系主要分布在0-60 cm的土层内,以植株为中心,呈放射状沿不同方向减小。通过研究所建马铃薯根长密度的空间分布函数能较好地反映根系的三维分布趋势。PRD灌溉可以刺激马铃薯根系生长,水分利用效率提高39%。进行PRD灌溉时应重点考虑滴头位置处及垄坡上的水盐变化,最好能起到节水控盐的双重作用。再生水PRD地下滴灌是对传统地表滴灌的优化和提升。 展开更多
关键词 地下滴灌 分根交替灌溉(PRD) 根长密度(RLD) 根重密度(RWD) 土壤水盐
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灌溉条件下包气带黄土层中NO_3^--N的深部运移 被引量:4
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作者 康银红 马耀光 王巧焕 《干旱地区农业研究》 CSCD 北大核心 2006年第6期147-150,182,共5页
通过渭北黄土塬地区NO3--N的原位运移试验,测定了10 m范围内黄土超根层中NO3--N浓度随时间的变化,对NO3--N和土壤含水量的运移通量及运移速率进行了定量分析。结果表明:微孔隙渗流的水分运移速率为44~65 mm/d,优先流的运移速率可达450 m... 通过渭北黄土塬地区NO3--N的原位运移试验,测定了10 m范围内黄土超根层中NO3--N浓度随时间的变化,对NO3--N和土壤含水量的运移通量及运移速率进行了定量分析。结果表明:微孔隙渗流的水分运移速率为44~65 mm/d,优先流的运移速率可达450 mm/d以上;NO3--N在施肥灌溉及作物吸收等因素的综合影响下形成积累峰值带,并向下运移,其平均运移速率为56.3 mm/d;在作物生长缓慢的冬季大定额灌溉条件下,施入农田的尿素并不能被作物完全吸收,上层土壤吸附的NO3--N会被大量淋洗,50%以上的NO3--N随入渗水流运移到作物根层以下,成为深层土壤和地下水的NO3--N污染来源。 展开更多
关键词 灌溉 黄土层 包气带 NO3^--N 深部运移
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局部灌水方式对玉米不同根区土-根系统水分传导的影响 被引量:27
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作者 胡田田 康绍忠 《农业工程学报》 EI CAS CSCD 北大核心 2007年第2期11-16,共6页
以管栽玉米进行分根实验,在均匀灌水、固定部分根区灌水和根系分区交替灌水3种方式下,分期测定两个1/2根区及整个根区的土-根系统总水分传导(简称水导)、单位根面积和单位根长水导,研究局部灌水方式对玉米不同根区土-根系统水分传导的... 以管栽玉米进行分根实验,在均匀灌水、固定部分根区灌水和根系分区交替灌水3种方式下,分期测定两个1/2根区及整个根区的土-根系统总水分传导(简称水导)、单位根面积和单位根长水导,研究局部灌水方式对玉米不同根区土-根系统水分传导的影响。结果表明:各阶段处理5d和10d时,总水导、单位根面积和单位根长水导一致表现为固定灌水和交替灌水的灌水区较之均匀灌水1/2根区均显著增大,说明局部灌水可以显著增强灌水区土-根系统水分传输的补偿效应。固定灌水时,灌水区水导始终显著大于非灌水区;交替灌水时,两个根区呈交替变化趋势。与固定灌水相比,交替灌水非灌水区的水分传导明显增大。因此,交替灌水能更好利用各部分根系资源以满足作物需水要求。 展开更多
关键词 局部灌水方式 不同根区 -根系统水分传导 补偿效应 玉米
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局部根区交替灌溉与氮素耦合对葡萄生长及15N-尿素利用的影响 被引量:6
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作者 陈丽楠 韩晓日 +1 位作者 孙占祥 刘秀春 《核农学报》 CAS CSCD 北大核心 2021年第2期447-453,共7页
为探讨局部根区交替灌溉与不同氮水平的耦合效应,采用盆栽试验,以两年生巨峰葡萄幼树为试材,利用15N标记示踪技术,设不同灌溉方式(传统双侧滴灌、固定根区滴灌、交替根区滴灌,分别记为CDI、FDI、ADI)和施氮水平(施氮量为0.4、0.8、1.2 g... 为探讨局部根区交替灌溉与不同氮水平的耦合效应,采用盆栽试验,以两年生巨峰葡萄幼树为试材,利用15N标记示踪技术,设不同灌溉方式(传统双侧滴灌、固定根区滴灌、交替根区滴灌,分别记为CDI、FDI、ADI)和施氮水平(施氮量为0.4、0.8、1.2 g·kg^(-1)土,分别记为N1、N2、N3),研究局部根区交替灌溉与不同氮水平耦合对葡萄生长指标、氮素的吸收与分配及15N肥料利用率的影响。结果表明,与CDI相比,FDI和ADI葡萄新梢修剪量平均显著降低21.3%和13.5%,同一灌溉方式下,葡萄新梢修剪量随施氮量的增加而增加。果实干物质量和当年生物量均表现为ADI>CDI>FDI,FDI和ADI的果实干物质量随着施氮量增加而增加,CDI的果实干物质量在N2最高。ADI果实的Ndff值明显高于CDI和FDI,主蔓和根砧等贮藏器官的Ndff值于不同灌溉方式间差异较小。随着施氮量的增加,葡萄各器官Ndff值降低。ADI的15N肥料利用率最高,分别比CDI和FDI平均显著提高1.3和6.0个百分点,且15N肥料利用率随着施氮量的增加而降低。总之,根区交替灌溉(ADI)与中等施氮量(N2)耦合既能协调葡萄的生长,获得较高的果实干物质积累,又能获得较高的氮肥利用率。本研究为葡萄高产与水氮高效协调栽培提供了理论依据。 展开更多
关键词 葡萄 根区交替滴灌 施氮量 氮肥利用率 15N示踪
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Groundwater recharge under irrigated agro-ecosystems in the North China Plain: From a critical zone perspective 被引量:4
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作者 MIN Leilei QI Yongqing +3 位作者 SHEN Yanjun WANG Ping WANG Shiqin LIU Meiying 《Journal of Geographical Sciences》 SCIE CSCD 2019年第6期877-890,共14页
From a critical zone perspective, the present paper aims to present the magnitude of groundwater recharge under different agricultural land-use types, reveal the process of water and solute transport in thick vadose z... From a critical zone perspective, the present paper aims to present the magnitude of groundwater recharge under different agricultural land-use types, reveal the process of water and solute transport in thick vadose zone, evaluate the "time lag" effect of recharge, and underscore the role of thickening vadose zone in recharge. The results indicated that different agricultural land-use types need to be further considered in recharge rate estimate. Under the typical irrigation condition in the piedmont plain, the recharge rate under flood irrigated winter wheat and summer maize(W/M_F), maize(M), non-cultivation(NC), native vegetation(NV), vegetables(V), and orchards(O) is 206.4, 149.7, 194.1, 46.4, 320.0, and 48.6 mm/yr, respectively. In the central plain, the value under W/M_F, M, NC, V, and cotton(C) is 92.8, 50.8, 85.0, 255.5, and 26.5 mm/yr, respectively. Soil water residence time(several years) and groundwater level response time(several months) should be distinguished to further understand the processes of groundwater recharge, because the soil water displacement velocities range from 0.2 to 2.2 m/yr while the rate of wetting front propagation is approximately 47 m/yr in the piedmont plain. The thickening vadose zone would prolong residence time of soil water and contaminant, which could postpone the time of or alleviate groundwater pollution, but have no significant influence on the magnitude of recharge in a long time scale. Recharge coefficient based on shorter time span(e.g. 2 or 3 years) should be used with caution as a parameter for groundwater resources evaluation, because it varies with total water input and target soil depth. Uncertainties in evapotranspiration and other water balance components should be evaluated in recharge estimation and the impact of land-use types on recharge should be emphasized. The critical zone science would greatly improve the understanding of groundwater recharge processes. The results of the present study will be helpful in sustainable groundwater resources management. 展开更多
关键词 GROUNDWATER RECHARGE critical zone irrigated AGRO-ECOSYSTEMS NORTH China PLAIN
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Applying a salinity response function and zoning saline land for three fi eld crops: a case study in the Hetao Irrigation District, Inner Mongolia, China 被引量:3
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作者 TONG Wen-jie CHEN Xiao-li +4 位作者 WEN Xin-ya CHEN Fu ZHANG Hai-lin CHU Qing-quan Shadrack Batsile Dikgwatlhe 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第1期178-189,共12页
Salinity is one of the major abiotic factors affecting the growth and productivity of crops in Hetao Irrigation District, China. In this study, the salinity tolerances of three local crops, wheat (Triticum aestinum L... Salinity is one of the major abiotic factors affecting the growth and productivity of crops in Hetao Irrigation District, China. In this study, the salinity tolerances of three local crops, wheat (Triticum aestinum L.), maize (Zea mays L.) and sunflower (Helianthus annuus L.), growing in 76 farm fields are evaluated with modified discount function. Salinity ecological zones appropriate for these local crops are characterized and a case study is presented for crop salinity ecological zoning. The results show that the yield reductions of wheat, maize and sunflower when grown in saline soils are attributed primarily to a reduction in spikelet number, 1 000-grain weight and seed number per head, respectively. Sunflower is the most tolerant crop among the three which had a salinity tolerance index (ST-index) of 12.24, followed by spring maize and spring wheat with ST-Indices of 9.00 and 7.43, respectively. According to the crop salinity tolerance results, the arable land in the Heping Village of this district was subdivided into four salinity ecological zones: the most suitable, suitable, sub-suitable and unsuitable zones. The area proportion of the most suitable zone for wheat, maize and sunflower within the Heping Village was 27.5, 46.5 and 77.5%, respectively. Most of the most suitable zone occurred in the western part of the village. The results of this study provide the scientific basis for optimizing the local major crop distribution and improving cultural practices management in Hetao Irrigation District. 展开更多
关键词 salinity tolerance modified discount function ecological zoning Hetao irrigation District
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Alternate Furrow Irrigation: A Practical Way to Improve Grape Quality and Water Use Efficiency in Arid Northwest China 被引量:6
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作者 DU Tai-sheng KANG Shao-zhong +1 位作者 YAN Bo-yuan ZHANG Jian-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第3期509-519,共11页
Field experiments were conducted for two years to investigate the benefits of alternate furrow irrigation on fruit yield, quality and water use efficiency of grape (Vitis vinifera L. cv. Rizamat) in the arid region ... Field experiments were conducted for two years to investigate the benefits of alternate furrow irrigation on fruit yield, quality and water use efficiency of grape (Vitis vinifera L. cv. Rizamat) in the arid region of Northwest China. Two irrigation treatments were included, i.e., conventional furrow irrigation (CFI, two root-zones were simultaneously irrigated during the consecutive irrigation) and alternate partial root-zone furrow irrigation (AFI, two root-zones were alternatively irrigated during the consecutive irrigation). Results indicate that AFI maintained similar photosynthetic rate (Pn) but with a reduced transpiration rate when compared to CFI. As a consequence, AFI improved water use efficiency based on evapotranspiration (WUEEr, fruit yield over water consumed) and irrigation (WUE~, fruit yield over water irrigated) by 30.0 and 34.5%, respectively in 2005, and by 12.7 and 17.7%, respectively in 2006. AFI also increased the edible percentage of berry by 2.91-4.79% significantly in both years. Vitamin C (Vc) content content of berry was increased by 25.6-37.5%, and tritrated acidity (TA) was reduced by 9.5-18.1% in AFI. This resulted in an increased total soluble solid content (TSS) to TA ratio (TSS/TA) by 11.5-16.7% when compared to CFI in both years. Our results indicate that alternate furrow irrigation is a practical way to improve grape fruit quality and water use efficiency for irrigated crops in arid areas. 展开更多
关键词 alternate furrow irrigation partial root-zone irrigation fruit yield water use efficiency fruit quality grape(Fitis vinifera L.
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Analysis of microstructure and performance of temper bead welded joints for SA508-3 steel by Quenching and Tempering mode 被引量:1
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作者 Qin Jian Li Shiqian +2 位作者 Lv Xiaochun Zhang Huiwen Du Bing 《China Welding》 EI CAS 2017年第1期15-20,共6页
The HAZ microstructure and performance of Quenching and Tempering mode temper bead welding and general welded joints which were made on SA508-3 steel of 60 mm thickness were compared in this article. The result shows ... The HAZ microstructure and performance of Quenching and Tempering mode temper bead welding and general welded joints which were made on SA508-3 steel of 60 mm thickness were compared in this article. The result shows that tempering sorbite which has excellent overall performance was obtained in both modes. The microstructure of Quenching and Tempering mode welded joints got more fine grain. Even though the hardness of tempering bead welded joints is higher than the general one,it still meets the standards which is lower than 350 HV. The impact absorbing energy of each district of tempering bead welded joints HAZ reached 170 J,which is equal to general one. 展开更多
关键词 SA508 -3 steel TEMPER BEAD welding Quenching and Tempering mode coarse GRAIN HEAT AFFECTED zone inter critical-coarse GRAIN HEAT AFFECTED zone
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Spatial-temporal variation of the land surface temperature field and present-day tectonic activity 被引量:1
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作者 Jin Ma Shunyun Chen Xiaoyan Hu Peixun Liu Liqiang Liu 《Geoscience Frontiers》 SCIE CAS 2010年第1期57-67,共11页
This study attempts to acquire information on tectonic activity in western China from land surface temperature (LST) field data. On the basis of the established relationship between heat and strain, we analyzed the ... This study attempts to acquire information on tectonic activity in western China from land surface temperature (LST) field data. On the basis of the established relationship between heat and strain, we analyzed the LSTdistribution in western China using the satellite data product MODIS/Terra. Our results show that: 1. There are departures from annual changes of LSTin some areas, and that these changes are associated with the activity of some active tectonic zones. 2. When annual-change background values caused by climate factors are removed, the long-period component (LSTLow) of temperature residual (AT) of the LSTis able to serve as an indicator for tectonic activity. We have found that a major earthquake can produce different effects on the/ST fields of surrounding areas. These effects are characterized by both rises and drops in temperature. For example, there was a noteworthy temperature decline associated with the Sumatran M9 earthquake of 2004 in the Bayan Har-Songpan block of central Tibetan Plateau. 3. On the other hand, the LST field of a single area may respond differently to major shocks occurring in different areas in the regions surrounding China. For instance, the Kun- lun M 8.1 event made the LSTon the Longmen Mountains fault zone increase, whereas the Zaisan Lake M 7.9 quake of 2003, and the Sumatran M 9 event of 2004, caused decreases in the same area's LST. 4. The variations of land surface temperature (LST) over time are different in different tectonic areas. These phenomena may provide clues for the study of tectonic deformation processes. On the basis of these phenomena, we use a combi- nation of temperature data obtained at varied depths, regional seismicity and strain results obtained with GPS measurements, to test the information related to tectonic activity derived from variations of the LST field, and discuss its implications to the creation of models of regional tectonic deformation. 展开更多
关键词 Land surtace temperature(LST) field North-south seismic zone(N-S seismic zone Bayan Har - Songpanblock Present-day tectonicactivity EARTHQUAKE
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Screening of chemokine receptor CCR4 antagonists by capillary zone electrophoresis 被引量:1
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作者 Zhe Sun Lin-Jie Tian +3 位作者 Qian Lin Xiao-Mei Ling Jun-Hai Xiao Ying Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第4期264-269,共6页
CC chemokine receptor 4(CCR4)is a kind of G-protein-coupled receptor,which plays a pivotal role in allergic inflammation.The interaction between 2-(2-(4-chloro-phenyl)-5-{[(naphthalen-1-ylmethyl)-carbamlyl]-methyl-4-o... CC chemokine receptor 4(CCR4)is a kind of G-protein-coupled receptor,which plays a pivotal role in allergic inflammation.The interaction between 2-(2-(4-chloro-phenyl)-5-{[(naphthalen-1-ylmethyl)-carbamlyl]-methyl-4-oxo-thiazolidin-3-yl)-N-(3-morpholin-4-yl-propyi)-acetamide(S009)and the N-terminal extracellular tail(ML40)of CCR4 has been validated to be high affinity by capillary zone electrophoresis(CZE).The S009 is a known CCR4 antagonist.Now,a series of new thiourea derivatives have been synthesized.Compared with positive control S009,they were screened using ML40 as target by CZE to find some new drugs for allergic inflammation diseases.The synthesized compounds XJH-5,XJH-4,XJH-17 and XJH-1 displayed the interaction with ML40,but XJH-9,XJH-10,XJH-I 1,XJH-12,XJH-13,XJH-14,XJH-3,XJH-8,XJH-6,XJH-7,XJH-15,XJH-16 and XJH-2 did not bind to ML40.Both qualification and quantification characterizations of the binding were determined.The affinity of the four compounds was valued by the binding constant,which was similar with the results of chemotactic experiments.The established CEZ method is capable of sensitive and fast screening for a series of lactam analogs in the drug discovery for allergic inflammation diseases. 展开更多
关键词 Capillary zone electrophoresis CCR4 antagonist 2-(2-(4-chloro-phenyl)-5-{[(naphthalen-1-ylmethyl)-carbamoyl]-methyl}-4-oxo-thiazoli-din-3-yl)-N-(3-morpho-lin-4-yl-propyl)-aceta-mide Interactions Structural modification
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On the Effect of Mist Flow on the Heat Transfer Performances of a Three-Copper- Sphere Configuration
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作者 Karema A.Hamad Yasser A.Mahmood 《Fluid Dynamics & Materials Processing》 EI 2023年第11期2863-2875,共13页
The cooling of a(pebble bed)spent fuel in a high-temperature gas-cooled reactor(HTGR)is adversely affected by an increase in the temperature of the used gas(air).To investigate this problem,a configuration consisting ... The cooling of a(pebble bed)spent fuel in a high-temperature gas-cooled reactor(HTGR)is adversely affected by an increase in the temperature of the used gas(air).To investigate this problem,a configuration consisting of three copper spheres arranged in tandem subjected to a forced mistflow inside a cylindrical channel is considered.The heat transfer coefficients and related variations as a function of Reynolds number are investigated accord-ingly.The experimental results show that when compared to those with only airflow,the heat transfer coefficient of the spherical elements with mistflow(j=112 kg/m2 hr,Re=55000)increases by 180%,75%,and 20%,respec-tively for thefirst,second,and third spherical element(the corresponding heat transfer enhancement ratio being 2.3,1.4,and 1.1).Additional numerical simulations reveal that the presence of stagnant zones with intense vortex formation around each spherical element contributes significantly to determine the heat transfer behavior. 展开更多
关键词 Mistflow mist irrigation density heat transfer coefficient vortex zone water droplet settling
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Transpressive Deformation across Tongbo-Dabie Orogenic Belt
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作者 Suo Shutian Zhou HanwenChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期5-12,共8页
Deformation characteristics of the dextral Dashankou ductile shear zone , parallel to the Tongbo-Dabie Orogenic Belt and regional stretching lineation patterns within the blueschist belt in Northern Hubei , China , ar... Deformation characteristics of the dextral Dashankou ductile shear zone , parallel to the Tongbo-Dabie Orogenic Belt and regional stretching lineation patterns within the blueschist belt in Northern Hubei , China , are examined at various scales , respectively . The new data , combined with those obtained in the Wudangshan area , indicate a transpressive deformation involving a WNW directed nearly horizontal shearing accompanied by shortening across the orogenic belt . A kinematic model is proposed for development of the deformation within the Tongboshan segment . Based on these findings it can be seen that the convergence and collision between the North China Craton and the Yangtze Craton may locally be oblique during the Proterozoic Jinningian Orogeny . This oblique collision is probably related to a certain extent to the shapes of the older craton margins . 展开更多
关键词 Tongbo - Dabie Orogenic Belt collision tectonics transpressive deformation shear zone stretching lineation .
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Development of Melanoma and Cancer without Decreasing of Cambial Cells Number in Morphofunctional Zones
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作者 Tatiana M. Yavisheva Sergey D. Shcherbakov 《Advances in Bioscience and Biotechnology》 2014年第6期493-500,共8页
In age groups from 20 to 60 years old, proliferation and differentiation of cells happen in a morphofunctional zone, in the electric field excited by 12 pairs of mother and daughter cells, turned out at cambial cells ... In age groups from 20 to 60 years old, proliferation and differentiation of cells happen in a morphofunctional zone, in the electric field excited by 12 pairs of mother and daughter cells, turned out at cambial cells division. Thus in daughter cells the Src SH2 domain necessary both for cytoskeleton formation and tyrosinase activization is activated. If the conditions for strengthening of tyrosinase activity are created in organism, the portion of Src participating in the cytoskeleton building can decrease to critical level that will lead to development of a malignant tumor. If action of a stimulating factor is quite strong, proliferation of malignant cells begins at a stage of melanocyte, and a melanoma occurs. If action of factors is long and not strong, more remote descendants of daughter cells proliferate, and a cancer appears. In order that there will be a normal differentiation of malignantly changed daughter cells, it is necessary to block the tyrosinase. Thus all SH2 domains will go on cell cytoskeleton formation. 展开更多
关键词 Morphofunctional zone at PEOPLE of 20 - 60 Years OLD Tirosinase MELANOMA CANCER
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