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沙漠增温效应下膜下滴灌棉田的小气候特征研究 被引量:2
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作者 塔依尔 徐铭 +3 位作者 吕新 刘玉国 胡小琴 孟小玉 《新疆农业科学》 CAS CSCD 2007年第5期549-552,共4页
根据沙漠增温效应下膜下滴灌棉田植被层内小气候观测资料,分析研究了棉田植被层内的净辐射、地温和相对湿度的变化。试验研究表明,膜下滴灌棉花花铃期在光、温、湿等方面具有较好配置,从而可充分利用光热资源,提高棉花的产量和品质。
关键词 沙漠增温效应 棉花 膜下滴灌
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Hawking radiation of a uniformly accelerating black hole 被引量:3
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作者 任军 曹江陵 赵峥 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2256-2259,共4页
In this paper, we study the Hawking radiation via tunnelling from a uniformly accelerating black hole. Although the Bekenstein-Hawking entropy is proportional also to the area of the event horizon, the radius of it, r... In this paper, we study the Hawking radiation via tunnelling from a uniformly accelerating black hole. Although the Bekenstein-Hawking entropy is proportional also to the area of the event horizon, the radius of it, rH, is a function of 0, which leads to the difficulties in the calculation of the emission rate. In order to overcome the mathematical difficulties, we propose a new technique to calculate the emission rate and the result obtained is reasonable. 展开更多
关键词 tunnelling effect Arnowitt-deser-Misner mass event horizon
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Acoustic Measurement
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《计量学报》 CSCD 1991年第S1期92-94,共3页
09001 The Calibration of a Reference SoundSource in Semianechoic Room. Yu Bo. Zhong Meie,Cheng Jianlin:1(3). 1980.pp.213--218.This paper describes the calibration method of areference Sound source.A set of calibration... 09001 The Calibration of a Reference SoundSource in Semianechoic Room. Yu Bo. Zhong Meie,Cheng Jianlin:1(3). 1980.pp.213--218.This paper describes the calibration method of areference Sound source.A set of calibration data for areference sound source type 4204 of A--power leveland sound power level in third octave band frequenciesin semianechoic room are given.The factors 展开更多
关键词 CALIBRATION AFFECTING instead ROOM DETERMINING ANALOG valent UNDERWATER analysed deser
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Miscellaneous Aspects in Measurement
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《计量学报》 CSCD 1991年第S1期99-102,共4页
13001 A Multiplex Data --acquisition and Data-processing System Using a Microprocessor. XiaXuesheng, Zhang Xianan: 2(2). 1981. pp.105--116.Through a study of an auiomatic--testing and da-ta--processing system for the ... 13001 A Multiplex Data --acquisition and Data-processing System Using a Microprocessor. XiaXuesheng, Zhang Xianan: 2(2). 1981. pp.105--116.Through a study of an auiomatic--testing and da-ta--processing system for the properties of hydraulic ele-ments. e, g. oil pump and oil motor. this 展开更多
关键词 hydraulic deser titled HARDWARE determ WAVEFORM TESTER rathe DRIFT FASTER
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Measurement of Temperature and Thermal Properties
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《计量学报》 CSCD 1991年第S1期47-56,共10页
02001 On the Realization of Intemational PracticalTemperature Scale of 1968 from 0℃ to 630 ℃.Pan Ruwen: 1 (1). 1980. pp.27--35.In present paper the apparatus and techniques used
关键词 TUNGSTEN SILVER apparatus Seale HEATING infra FREEZING outer INDIUM deser
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Ionizing Radiation Measurement
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《计量学报》 CSCD 1991年第S1期81-86,共6页
07001 Unfolding Whole Energy Range NeutronSpectrum from Activation Data by Nonlinear Programm-ing Method. Jiang Hongdi:1(4), 1980. pp.241--248.This paper introduces a new method in which nonlinearprogramming is applie... 07001 Unfolding Whole Energy Range NeutronSpectrum from Activation Data by Nonlinear Programm-ing Method. Jiang Hongdi:1(4), 1980. pp.241--248.This paper introduces a new method in which nonlinearprogramming is applied to determine the whole energyrange neutron spectrum from the activation data. Ac-cording to the different measuring condition. a set 展开更多
关键词 NEUTRON Activation cording determ deser ABSOLUTE ANGULAR deviation BORON EFFLUENT
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Lasers for Precision Measurements
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《计量学报》 CSCD 1991年第S1期96-98,共3页
11001 Iodine Saturated Absorption StabilizedHe--Ne Lasers. Shen Naicheng. Wu Yaoxiang, SunYimin, An Jialuan. Wang Chu: 1(2). 1980. pp.93--101This report describes the construction and operation ofan iodine saturated a... 11001 Iodine Saturated Absorption StabilizedHe--Ne Lasers. Shen Naicheng. Wu Yaoxiang, SunYimin, An Jialuan. Wang Chu: 1(2). 1980. pp.93--101This report describes the construction and operation ofan iodine saturated absorption stabilized He--Ne laserat NIM. and the results of the measurements of the fre-quency Stability and reproducibility.The frequency stabil- 展开更多
关键词 STABILIZED saturated ABSORPTION IODINE tuned IODINE LENGTH RESONATOR determ deser
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Measurement of Electromagnetic Quantities
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《计量学报》 CSCD 1991年第S1期63-71,共9页
04001 The Absolute Measurement of the Ampereby NMR Method. Qiao Weichuan: 1 (1). 1980. pp.2--15.This paper describes the principle, apparatus. experi-mectal procedure and uncertainties of theabsolute measurement of th... 04001 The Absolute Measurement of the Ampereby NMR Method. Qiao Weichuan: 1 (1). 1980. pp.2--15.This paper describes the principle, apparatus. experi-mectal procedure and uncertainties of theabsolute measurement of the ampere by nuclearmagnetic resonance method. A conversion factor be- 展开更多
关键词 MAGNETOMETER SQUID apparatus adding ABSOLUTE deser DISSIPATION eliminated determ hyster
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Optical Measurement
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《计量学报》 CSCD 1991年第S1期86-92,共7页
06001 The Exposure Standard. Lin Yunzhu,MaRunshan,. Guo Zhengqiang:1(4). 1980. pp.258--265.An exposure Standard apparatus developed in NIM ispresented, The exposure range of this apparatus isfrom 0.001 to 10 lux·... 06001 The Exposure Standard. Lin Yunzhu,MaRunshan,. Guo Zhengqiang:1(4). 1980. pp.258--265.An exposure Standard apparatus developed in NIM ispresented, The exposure range of this apparatus isfrom 0.001 to 10 lux·second. and the uncertainty ofthe exposure is not exceed ±0.01 logarithmic unit. Itbasically satisfies the requirements of Sensitometry andCan be used to calibrate different types ofsensitometers. 展开更多
关键词 EXPOSURE apparatus EXCEED UNCERTAINTY oximate deser logarithmic instrument ILLUMINATION ABSOLUTE
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Measurement of Time and Frequency
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《计量学报》 CSCD 1991年第S1期77-81,共5页
06001 Technical Requirements for VCXO used inthe Cesium Atomic Clock. Zheng Lisheng: 1(4), 1980.pp.316--320.Voltage controlled crystal oscillator (VCXO) plays an im-portant roll in the atomic frequency standard. Thepe... 06001 Technical Requirements for VCXO used inthe Cesium Atomic Clock. Zheng Lisheng: 1(4), 1980.pp.316--320.Voltage controlled crystal oscillator (VCXO) plays an im-portant roll in the atomic frequency standard. Theperformance of VCXO must be excellent so as to main- 展开更多
关键词 OSCILLATOR ATOMIC PUMPING OFFSET subsequent deser analysed inherent eliminating UNIFIED
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英译《大雅》
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《语言教育》 1996年第5期13-13,共1页
关键词 《大雅》 岂弟君子 HANDLE MOUNT killed deser FILLED
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短花针茅荒漠草原土壤氮素矿化对载畜率的响应 被引量:12
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作者 韩梦琪 潘占磊 +4 位作者 靳宇曦 秦洁 李江文 王忠武 韩国栋 《草业学报》 CSCD 北大核心 2017年第9期27-35,共9页
氮矿化是决定土壤提供可利用性氮的关键生态环节,同时也是当今国内外土壤氮素循环的研究热点,荒漠草原作为草地生态系统中极特殊的一种草地类型,其资源贫乏,气候严酷,植被结构相对简单,因此研究荒漠草原氮素的可利用性对维持荒漠草原稳... 氮矿化是决定土壤提供可利用性氮的关键生态环节,同时也是当今国内外土壤氮素循环的研究热点,荒漠草原作为草地生态系统中极特殊的一种草地类型,其资源贫乏,气候严酷,植被结构相对简单,因此研究荒漠草原氮素的可利用性对维持荒漠草原稳定发展十分必要。鉴于此,本研究以内蒙古四子王旗短花针茅荒漠草原为对象,采用顶盖埋管培养法,通过在整个生长季的跟踪调查,主要探讨了净氮矿化速率对4个载畜率梯度[0(对照)、0.91(轻度放牧)、1.82(中度放牧)、2.71(重度放牧)羊/(hm2·a)]的响应,并结合土壤温湿度,分析其与土壤氮矿化的关系,旨在为荒漠草原生态系统氮素可持续利用的研究提供基础数据及管理参考。结果显示,土壤的净氮矿化速率在整个生长季呈现出先降后增的趋势,并且在生长高峰期7月及8月受载畜率的影响较大。4种载畜率梯度下中度放牧处理[1.82羊/(hm2·a)]具有最高的净氮矿化速率,重度放牧处理中[2.71羊/(hm2·a)]净氮矿化速率最低。皮尔森相关分析表明硝化速率与净氮矿化速率显著正相关,在整个生长季中净氮矿化速率受硝化作用影响较大。不同载畜率梯度下,土壤水分与净氮矿化速率极显著负相关,而土壤温度则与净氮矿化速率无显著相关性。综上所述中度载畜率水平[1.82羊/(hm2·a)]是维持荒漠草原稳定矿化速率的理想载畜率。 展开更多
关键词 荒漠草原 氮矿化 载畜率
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