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“耗”的词义演变及演变动因分析
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作者 张颖 《今古文创》 2024年第2期134-136,共3页
“耗”的词义随着人们的使用、心理的联想以及语言内部的互动影响不断发展变化,由最初表示“一种稻子”演变为“损耗”“消息”“老鼠”等义项,成为一个多义词。在“耗”的词义演变过程中,既有词义引申,也有词性变化,“耗”词义演变的... “耗”的词义随着人们的使用、心理的联想以及语言内部的互动影响不断发展变化,由最初表示“一种稻子”演变为“损耗”“消息”“老鼠”等义项,成为一个多义词。在“耗”的词义演变过程中,既有词义引申,也有词性变化,“耗”词义演变的主要动因是隐喻和转喻。 展开更多
关键词 “耗” 词义演变 隐喻 转喻
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成岩过程中的“耗水作用”及其石油地质意义 被引量:40
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作者 张善文 《沉积学报》 CAS CSCD 北大核心 2007年第5期701-707,共7页
受济阳坳陷古近系中深部储层出现异常低压的启示,讨论了成岩过程中主要矿物蚀变的"耗水"问题,并从理论上计算了这种蚀变的耗水量。初步研究表明,成岩过程中矿物蚀变的"耗水作用"可使地层水大量减少,在没有外部流体... 受济阳坳陷古近系中深部储层出现异常低压的启示,讨论了成岩过程中主要矿物蚀变的"耗水"问题,并从理论上计算了这种蚀变的耗水量。初步研究表明,成岩过程中矿物蚀变的"耗水作用"可使地层水大量减少,在没有外部流体补充的情况下,相应地层必然呈低压状态,并与围岩形成一定的压力差,易于烃类进入成藏。 展开更多
关键词 成岩作用 “耗水作用” 蚀变 长石 高岭石
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“耗散”理论与开放教学 被引量:4
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作者 陈建先 陈万华 《学科教育》 北大核心 2002年第6期22-25,共4页
本文立足于课堂教学改革的前沿 ,以“耗散”结构理论透视当前小学课堂教学 ,提出要打破封闭的静态课堂 ,建立一个开放的充满活力的课堂教学新体系 ,关键是要实现课堂教学的“耗散”(即从有序→无序→有序 )
关键词 “耗散”理论 开放教学 小学教学 课堂教学 教学目标 教学评价 学科教学
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成岩过程中的“耗水”作用及其石油地质意义 被引量:11
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作者 张善文 《油气地球物理》 2006年第4期1-6,共6页
受济阳坳陷古近系中深部储层出现异常低压的启示,讨论了成岩过程中主要矿物蚀变的"耗水"问题,并从理论上计算了这种蚀变的耗水量。初步研究表明,成岩过程中矿物蚀变的"耗水"作用可使地层水大量减少,在没有足够外部... 受济阳坳陷古近系中深部储层出现异常低压的启示,讨论了成岩过程中主要矿物蚀变的"耗水"问题,并从理论上计算了这种蚀变的耗水量。初步研究表明,成岩过程中矿物蚀变的"耗水"作用可使地层水大量减少,在没有足够外部流体补充的情况下,相应地层必然呈低压状态,并与围岩形成一定的压力差,易于烃类进入成藏。 展开更多
关键词 成岩作用 “耗水”作用 蚀变 长石 高岭石
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Mechanical response and dilatancy characteristics of deep marble under different stress paths:A sight from energy dissipation
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作者 LIU Xiao-hui HAO Qi-jun +2 位作者 ZHENG Yu ZHANG Zhao-peng XUE Yang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2070-2086,共17页
Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses ... Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses on Jinping marble obtained from the Jinping Underground Laboratory in China at a depth of 2400 m.Various uniaxial and triaxial tests at different strain rates,along with constant confining pressure tests and reduced confining pressure tests under different confining pressures were conducted to analyze the mechanical response and dilatancy characteristics of the marble under four stress paths.Subsequently,a new empirical dilatancy coefficient is proposed based on the energy dissipation method.The results show that brittle failure characteristics of marble under uniaxial compression are more obvious with the strain rate increasing,and plastic failure characteristics of marble under triaxial compression are gradually strengthened.Furthermore,compared to the constant confining pressure,the volume expansion is relatively lower under unloading condition.The energy dissipation is closely linked to the process of dilatancy,with a rapid increase of dissipated energy coinciding with the beginning of dilatancy.A new empirical dilatancy coefficient is defined according to the change trend of energy dissipation rate curve,of which change trend is consistent with the actual dilatancy response in marble under different stress paths.The existing empirical and theoretical dilatancy models are analyzed,which shows that the empirical dilatancy coefficient based on the energy background is more universal. 展开更多
关键词 deep marble stress paths DILATANCY energy dissipation empirical dilatancy coefficient
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Research on fast detection method of infrared small targets under resourceconstrained conditions
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作者 ZHANG Rui LIU Min LI Zheng 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第4期582-587,共6页
Infrared small target detection is a common task in infrared image processing.Under limited computa⁃tional resources.Traditional methods for infrared small target detection face a trade-off between the detection rate ... Infrared small target detection is a common task in infrared image processing.Under limited computa⁃tional resources.Traditional methods for infrared small target detection face a trade-off between the detection rate and the accuracy.A fast infrared small target detection method tailored for resource-constrained conditions is pro⁃posed for the YOLOv5s model.This method introduces an additional small target detection head and replaces the original Intersection over Union(IoU)metric with Normalized Wasserstein Distance(NWD),while considering both the detection accuracy and the detection speed of infrared small targets.Experimental results demonstrate that the proposed algorithm achieves a maximum effective detection speed of 95 FPS on a 15 W TPU,while reach⁃ing a maximum effective detection accuracy of 91.9 AP@0.5,effectively improving the efficiency of infrared small target detection under resource-constrained conditions. 展开更多
关键词 infrared UAV image fast small object detection low impedance loss function
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Load-bearing characteristics and energy evolution of fractured rock masses after granite and sandstone grouting
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作者 WU Xu-kun ZHAO Guang-ming +4 位作者 MENG Xiang-rui LIU Chong-yan LIU Zhi-xi HUANG Shun-jie ZHANG Qi-hang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2810-2825,共16页
Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of ... Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of fractured rock mass.The strength and deformation features of grouting-reinforced rock mass were analyzed under different loading manners;the energy evolution mechanism of grouting-reinforced rock mass specimens with different particle sizes and features was investigated;the energy dissipation ratio and post-peak stress decreasing rate were employed to evaluate the bearing stability of grouting-reinforced rock mass.The results show that the strength and ductility of granite-reinforced rock mass(GRM)under biaxial loading are higher than that of sandstone-reinforced rock mass(SRM)under uniaxial loading.Besides,the energy evolution characteristics of grouting-reinforced rock mass under uniaxial and biaxial loading mainly could be divided into early,middle,and late stages.In the early stage,total,elastic,and dissipation energies were quite small with flatter curves;in the middle stage,elastic energy increased rapidly,whereas dissipation energy increased slowly;in the late stage,dissipation energy increased sharply.The energy dissipation ratio was used to represent the pre-peak plastic deformation.Under uniaxial loading,this ratio increased as the particle size increased and the pre-peak plastic deformation of grouting-reinforced rock mass became larger;under biaxial loading,it dropped as the particle size increased,and the pre-peak plastic deformation of grouting-reinforced rock mass became smaller.The post-peak stress decline rate A_(v) was used to assess the post-peak bearing performance of grouting-reinforced rock mass.Under uniaxial loading,parameter A_(v) exhibited reduction as the particle size kept increasing,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was greater,and the bearing capacity was greater;under biaxial loading,A_(v) increased with the particle size,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was low and the bearing capacity was reduced.The findings are considered instrumental in improving the stability of the roadway-surrounding rock by granite and sandstone grouting. 展开更多
关键词 grouting-reinforced rock mass particle size energy dissipation ratio post-peak stress decreasing rate load-bearing characteristics
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网络媒体与传统媒体的“耗散现象”浅析
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作者 韦劲 《图书情报论坛》 2000年第4期10-12,共3页
人们按照传播媒介方式的不同把媒体的发展划分为四个不同的阶段,纸媒介的报纸、电波媒介的广播、基于电视图像传播的电视分别被称为第一、第二和第三媒体(传统媒体),而伴随Internet的迅速发展。
关键词 网络媒体 传统媒体 “耗散现象” 媒体耦合
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欧盟环保领域立法的重要举措——解读“耗能产品环保设计要求的框架指令”(EuP指令) 被引量:4
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作者 陈妙农 《电器工业》 2004年第8期24-29,共6页
电气电子产品的制造及广泛使用在给人们带来极大方便的同时,也引发了两方面的负面影响:一方面导致全球电子垃圾剧增;另一方面电气电子产品的制造及使用过程都在一定程度上破坏了环境。仅以家用电器为例,据统计德国每年产生180万吨垃圾,... 电气电子产品的制造及广泛使用在给人们带来极大方便的同时,也引发了两方面的负面影响:一方面导致全球电子垃圾剧增;另一方面电气电子产品的制造及使用过程都在一定程度上破坏了环境。仅以家用电器为例,据统计德国每年产生180万吨垃圾,其中220万部电脑,300万台传真机,650万只电话和手机;整个欧洲每年产生600万吨电子垃圾。目前我国家用电器拥有量为4亿台电视机,1.7亿台洗衣机,1.3亿台电冰箱,1600万台电脑;待处置的设备估计还有1000万台电视机,500万台洗衣机,400万台电冰箱,500万台电脑。 展开更多
关键词 电气电子产品 电磁兼容性 立法 “耗能产品环保设计要求的框架指令”
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对正确认识和防止统战政策运行中“耗散”问题的探索
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作者 刘卫国 《辽宁省社会主义学院学报》 2002年第1期13-14,共2页
本文借用自然科学的概念和理论来研究统战政策在运行过程中所造成的“损耗和曲解”问题,分析了“耗散”的成因,并阐述了如何防止“耗散”的对策。
关键词 统战政策 运行中的“耗散”问题 探索
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企业“耗散结构体”论
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作者 周为尧 《经营与管理》 1989年第4期31-34,共4页
现代系统科学已从“老三论”即系统论、控制论和信息论发展到“新三论”即耗散结构论、协同论和突变论。两者极大地促进了世界科学技术领域的开拓,人类思维方式的变革和当代社会科学特别是经济科学与管理科学观念的深化,尤其是它们之间... 现代系统科学已从“老三论”即系统论、控制论和信息论发展到“新三论”即耗散结构论、协同论和突变论。两者极大地促进了世界科学技术领域的开拓,人类思维方式的变革和当代社会科学特别是经济科学与管理科学观念的深化,尤其是它们之间的相互联系、相互制约的关系,相互交叉的势态,高度综合的特点和向社会科学的扩展,已经引起了理论界和实际工作者深切的关注与重视。我国改革十年的实践表明,改革的核心,从微观方面分析,就是要解决在怎样的条件下才能保持企业始终处于良性循环。用耗散结构理论来看,则可归结为企业耗散结构能否形成的问题。 展开更多
关键词 中国 企业 “耗散结构体” 生产组织系统 管理组织系统 物资流 信息流
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通信枢纽楼能耗运行分析研究 被引量:1
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作者 樊春锋 伍建萍 《电信工程技术与标准化》 2016年第5期89-92,共4页
如何在业务量不断增加,电源容量无法扩容的情况下,更好地解决供电能力紧张、机房装机位不足、机房散热等问题,是本论文的研究意义所在。本文通过对S省通信枢纽楼能耗运行分析,给出以上难点的合理化建议和建设指导原则。
关键词 枢纽楼 变压器 红色预警 搬迁
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Research advances on the biological effects of elevated ultraviolet-B radiation on terrestrial plants 被引量:8
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作者 吴家兵 关德新 +1 位作者 袁凤辉 张新建 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第4期383-390,I0008,共9页
This review describes the effects of ultraviolet-B (UV-B) radiation on plant growth and development, photosynthesis and photosynthetic pigments and UV-B absorbing compounds. Moreover, plant ecosystem level responses... This review describes the effects of ultraviolet-B (UV-B) radiation on plant growth and development, photosynthesis and photosynthetic pigments and UV-B absorbing compounds. Moreover, plant ecosystem level responses to elevated UV-B radiation and interactions of UV-B radiation with abiotic and biotic factors were also involved. Results collected in this review suggest that approximately two-thirds terrestrial plant species are significantly affected by increase in UV-B radiation, The majority of evidences indicate that elevated UV-B radiation is usually detrimental but there exists tremendous variability in the sensitivity of species to UV-B radiation, and sensitivity also differs among cultivars of the same species. 展开更多
关键词 ultraviolet radiation ozone depletion PHOTOSYNTHESIS environment stress
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Purification of metallurgical grade silicon by electrorefining in molten salts 被引量:5
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作者 蔡靖 罗学涛 +4 位作者 卢成浩 Geir Martin HAARBERG Annabelle LAURENT Ole Edvard KONGSTEIN 王淑兰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期3103-3107,共5页
Electrochemical studies on silicon deposition were performed in molten salt electrolytes. Purification of metallurgical grade silicon by electrorefining was carried out in molten Si-chloride salts at temperatures from... Electrochemical studies on silicon deposition were performed in molten salt electrolytes. Purification of metallurgical grade silicon by electrorefining was carried out in molten Si-chloride salts at temperatures from 973 K to 1223 K. It was found that the use of a liquid alloy anode of silicon and copper was beneficial in molten CaCl2 with NaCl, CaO and dissolved Si. ICP-AES analysis results showed efficient removal of metal impurities, such as titanium, aluminum and iron, which are present in significant quantities in the feedstock. The contents of boron and phosphorus in the silicon after electrorefining were reduced from 36×10-6 and 25×10-6 to 4.6×10-6 and 2.8 ×10-6, respectively. The energy consumption of electrorefining was estimated to be about 9.3 kW?h/kg. 展开更多
关键词 ELECTROREFINING molten salt Si-Cu alloy SILICON PURIFICATION energy consumption
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A low-phase-noise and low-power crystal oscillator for RF tuner 被引量:4
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作者 唐路 王志功 +1 位作者 曾贤文 徐建 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期21-24,共4页
A 37. 5 MHz differential complementary metal oxide semiconductor (CMOS) crystal oscillator with low power and low phase noise for the radio frequency tuner of digital radio broadcasting digital radio mondiale (DRAM... A 37. 5 MHz differential complementary metal oxide semiconductor (CMOS) crystal oscillator with low power and low phase noise for the radio frequency tuner of digital radio broadcasting digital radio mondiale (DRAM) and digital audio broadcasting (DAB) systems is realized and characterized. The conventional cross-coupled n-type metal oxide semiconductor (NMOS) transistors are replaced by p-type metal oxide semiconductor (PMOS) transistors to decrease the phase noise in the core part of the crystal oscillator. A symmetry structure of the current mirror is adopted to increase the stability of direct current. The amplitude detecting circuit made up of a single- stage CMOS operational transconductance amplifier (OTA) and a simple amplitude detector is used to improve the current accuracy of the output signals. The chip is fabricated in a 0. 18- pxn CMOS process, and the total chip size is 0. 35 mm x 0. 3 mm. Under a supply voltage of 1.8 V, the measured power consumption is 3.6 mW including the output buffer for 50 testing loads. The proposed crystal oscillator exhibits a low phase noise of - 134. 7 dBc/Hz at 1-kHz offset from the center frequency of 37. 5 MHz. 展开更多
关键词 complementary metal oxide semiconductor(CMOS) crystal oscillator phase noise power consumption
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Synthesis Scheme for Low Power Designs Under Timing Constraints 被引量:5
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作者 王玲 温东新 +1 位作者 杨孝宗 蒋颖涛 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第2期287-293,共7页
To minimize the power consumption with resources operating at multiple voltages a time-constrained algorithm is presented.The input to the scheme is an unscheduled data flow graph (DFG),and timing or resource constrai... To minimize the power consumption with resources operating at multiple voltages a time-constrained algorithm is presented.The input to the scheme is an unscheduled data flow graph (DFG),and timing or resource constraints.Partitioning is considered with scheduling in the proposed algorithm as multiple voltage design can lead to an increase in interconnection complexity at layout level.That is,in the proposed algorithm power consumption is first reduced by the scheduling step,and then the partitioning step takes over to decrease the interconnection complexity.The time-constrained algorithm has time complexity of O(n 2),where n is the number of nodes in the DFG.Experiments with a number of DSP benchmarks show that the proposed algorithm achieves the power reduction under timing constraints by an average of 46 5%. 展开更多
关键词 low power multiple supply voltages partitioning timing constraints SCHEDULING
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Design and Analysis of Analog Front-End of Passive RFID Transponders 被引量:5
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作者 胡建赟 何艳 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第6期999-1005,共7页
An analog front-end of HF passive RFID transponders compatible with ISO/IEC 18000-3 is presented.Design considerations, especially the power transmission in the RFID transponder, are analyzed. Based on these considera... An analog front-end of HF passive RFID transponders compatible with ISO/IEC 18000-3 is presented.Design considerations, especially the power transmission in the RFID transponder, are analyzed. Based on these considerations,an analog front-end is presented with novel architecture, high power conversion efficiency, low voltage, low power consumption, and high performance in an environment of noise and power fluctuation. The circuit is implemented in a Chartered 0.35μm standard CMOS process. The experimental results show that the chip can satisfy the design target well. 展开更多
关键词 RFID analog front-end power transmission ARCHITECTURE low power
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Temperature Dependence of Atmospheric NO3 Loss Frequency 被引量:3
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作者 李素文 谢晶华 +2 位作者 陈得宝 姜恩华 汪徐德 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第2期145-149,I0003,共6页
A new indicator with temperature dependence of the NO3 loss frequency, was developed to study the contribution of NO3 to the oxidation of monoterpenes and NOx removal in the atmosphere. The new indicator arises from t... A new indicator with temperature dependence of the NO3 loss frequency, was developed to study the contribution of NO3 to the oxidation of monoterpenes and NOx removal in the atmosphere. The new indicator arises from the temperature dependence of kinetic constant. The new indicator was applied to data of observation based on differential optical absorption spectroscopy system on the outskirts of Hefei, China. According to the findings, the contribution of monoterpenes to the loss of NO3 was 70%-80%. 展开更多
关键词 NO3 Differential optical absorption spectroscopy INDICATOR Loss frequency Oxidation capacity
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Low Power Polarity Conversion Based on the Whole Annealing Genetic Algorithm 被引量:4
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作者 汪鹏君 陆金刚 +1 位作者 陈恳 徐建 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第2期298-303,共6页
For an n-variable logic function,the power dissipation and area of the REED-MULLER (RM) circuit corresponding to each polarity are different. Based on the propagation algorithm of signal probability,the decompositio... For an n-variable logic function,the power dissipation and area of the REED-MULLER (RM) circuit corresponding to each polarity are different. Based on the propagation algorithm of signal probability,the decomposition algorithm of a multi-input XOR/AND gate,and the multiple segment algorithm of polarity conversion,this paper successfully applies the whole annealing genetic algorithm (WAGA) to find the best polarity of an RM circuit. Through testing eight large-scale circuits from the Microelectronics Center North Carolina (MCNC) Benchmark, the SYNOPSYS synthesis results show that the RM circuits corresponding to the best polarity found using the proposed algorithm attain average power,area,and max delay savings of 77.2% ,62.4% ,and 9.2% respectively,compared with those under polarity 0. 展开更多
关键词 whole annealing genetic algorithm REED-MULLER low power polarity conversion
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Effects of Different Irrigation Amounts on Water Consumption and Water Use Efficiency of Greenhouse Cucumber 被引量:6
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作者 郭生虎 孔德杰 +2 位作者 张源沛 郑国宝 朱金霞 《Agricultural Science & Technology》 CAS 2010年第9期217-220,共4页
[Objective] This study was to investigate the effects of different irrigation amount on water consumption and water use efficiency of greenhouse cucumber.[Method]Under the condition of drip irrigation with different w... [Objective] This study was to investigate the effects of different irrigation amount on water consumption and water use efficiency of greenhouse cucumber.[Method]Under the condition of drip irrigation with different water amounts in sunlight greenhouse of the arid areas in Ningxia,the soil water was measured and the water consumption of crop was calculated.[Result]When irrigation amount was 563 mm,the water consumption as a whole gradually increased with the delay of growth period,reached peak during the thriving stage of fruit setting,and then gradually declined;in each treatment,the daily water consumption increased with the increasing of irrigation amount during each growth period.However,the consumption of soil moisture reduced with the significant increase of irrigation.563 mm of irrigation amount could meet the water requirements of cucumber and began to add water to soil,and water utilization efficiency could reach 33.4 kg/m3.[Conclusion]The research had provided theoretical basis for water management in the production process of greenhouse cucumber. 展开更多
关键词 GREENHOUSE CUCUMBER Irrigation amount Water consumption Water utilization efficiency
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