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330 KU transmission system in Northwest china

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electricity 1992年第3期 42-44页

作者： Cheng Jiangeng Northwest china electric power Design institute

*** reviewThe first 330 kV transmission line in Northwest china fromLiujiaxia Hydro power Station through Qinan Substation to TangyuSubstation was commissioned in *** the seventies,accompany-ing the commissioning of H... 详细信息

关键词： Northwest mostly transm Plateau Qinghai accompanying strengthened Insulator Gansu strings

Analysis of leakage current in GaAs micro-solar cell arrays

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Science china(Technological Sciences) 2010年第5期53卷 1240-1246页

作者： WANG YanShuo1,CHEN NuoFu1,2,3,ZHANG XingWang1,BAI YiMing1,WANG Yu1,HUANG TianMao1,ZHANG Han1 & SHI HuiWei1 1 Key Laboratory of Semiconductor Materials Science,institute of Semiconductors,Chinese Academy of Sciences,PO Box 912,Beijing 100083,china 2 School of Renewable Energy Engineering,North china electric power University,Beijing 102206,china 3 National Laboratory of Micro-Gravity,institute of Mechanics,Chinese Academy of Sciences,Beijing 100080,china Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences School of Renewable Energy Engineering North China Electric Power University National Laboratory of Micro-Gravity Institute of Mechanics Chine

The output characteristics of micro-solar cell arrays are analyzed on the basis of a modified model in which the shunt resistance between cell lines results in current *** modification mainly consists of adding a shunt resistor network to the traditional *** obtained results agree well with the reported experimental *** calculation results demonstrate that leakage current in substrate affects seriously the performance of GaAs micro-solar cell *** performance of arrays can be improved by reducing the number of cells per *** addition,at a certain level of integration,an appropriate space occupancy rate of the single cell is recommended for ensuring high open circuit voltages,and it is more appropriate to set the rates at 80%-90% through the calculation.

关键词： micro-solar cell MEMS(micro-electromechanical systems) leakage current

An ecological hydraulic radius approach to estimate the instream ecological water requirement

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Progress in Natural Science:Materials International 2007年第3期17卷 320-327页

作者： LIU Changming and MEN Baohui ( Key Laboratory of Water Cycle and Related Land Surface Process, institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, china Key Laboratory of Water and Sediment Sciences, Ministry of Education & Water Sciences College, Beijing Normal University, Beijing 100875, china Department of Hydraulic and Hydropower Engineering, North china electric power University, Beijing 102206, china) Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China. Key Laboratory of Water and Sediment Sciences Ministry of Education & Water Sciences College Beijing Normal University Beijing 100875 China. Department of Hydraulic and Hydropower Engineering North China Electric Power University Beijing 102206 China

This essay defines the concepts of ecological flow velocity as well as ecological hydraulic radius (EHR) and proposes an ecological hydraulic radius approach (EHRA) which considers both the watercourse information (including hydraulic radius, roughness coefficient and hydraulic gradient) and the required stream velocity necessary for maintenance of certain ecological functions all together. The key parameter of EHRA is to fix the watercourse cross-sectional flow area corresponding to EHR, by which the relation between parabola shaped cross-sectional flow area and hydraulic radius is deduced. The EHRA not only meets the requirement of flow velocity for adequate fish spawning migration, but also is applicable to the ecological flows in regard with other ecological issues (such as the calculation of the instream flow requirements for transporting sediment and for pollution self-purification, etc.). This essay has illuminated the computational process taking the estimation of ecological water requirement of Zhuba Hydrologyical Station watercourse in Niqu branch of the Yalong River as an example. Additionally, we compare EHRA with Tennant approach. The result shows that the Zhuba Hydrological Station ecological water requirement calculated by EHRA lies between the minimum and favorable ecological water requirement calculated by the Tennant approach. This is due to the fact that the ecological flow velocity (such as the fish spawning migration flow velocity) was taken into consideration, producing results applicable to the practical situation.

关键词： ecological flow flow velocity cross-sectional flow area ecological hydraulic radius (HER) instreamecological water requirement.

Some Hotspots Concerned with Smart Grid

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electricity 2010年第3期21卷 15-19页

作者： Wang Mingjun china electric power Research institute Yang Hexiu china electric power Research institute

The smart grid has been such a hot topic *** this paper the hot topics in this field,such as the definition and features of smart grid,key technical problems to be addressed such as new system components,new types of transducers and measurement technologies,advanced interfaces,event-driven fast-simulated decision-making and coordination,and adaptive control,etc.,and diff iculties are analyzed and discussed.

关键词： smart grid smart meter demand response (DR) multi-agent

Estimating Soil Erosion in northeast china Using ^(137)Cs and ^(210)Pbex

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Pedosphere 2011年第6期21卷 706-711页

作者： YANG Yu-Hong YAN Bai-Xing ZHU Hui Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 （China） College of Water Resources North China University of Water Resources and Electric Power Zhengzhou 450011 （China）

Evaluation of soil erosion in agricultural fields is valuable to develop conservation practices for reducing agricultural nonpoint source pollution. Soil erosion rates were quantified using the fallout radionuclide tracer technique in Mojiagou Basin located on the outskirts of Changchun in northeast china. The calculated soft erosion rates in the study area were 1.99 and 1.85 mm year-1 using 137Cs and excess 210pb （210Pbex） measurements, respectively. Both fallout radionuclides showed a similar tendency at downslope sites. All measured sites have experienced net erosion during the past 50 to 100 years. 137Cs and 210Pbex measurements were useful to quantify soil erosion rates on field and small basin scales. At this rate of erosion, the current fertile topsoil layer would be entirely removed within 70 years.

关键词： black soil fallout radionuclide tracer technique rainfall erosivity reference inventory soil loss

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自制桥式差分电容测量电路

武汉理工大学学报 2009年第24期31卷 78-82页

作者：赵礼杰东北电力大学输变电技术学院吉林132012

差分电容传感器电路采用交流电电容桥法对差分电容进行测量。此方法所采用的载波信号为100 kHz的高频交流信号。相位敏感解调器将输出的高频交流信号转化为直流信号输出之后,利用RS-232电缆将电压表与电脑连接起来,对输出电压进行记录... 详细信息

差分电容传感器电路采用交流电电容桥法对差分电容进行测量。此方法所采用的载波信号为100 kHz的高频交流信号。相位敏感解调器将输出的高频交流信号转化为直流信号输出之后,利用RS-232电缆将电压表与电脑连接起来,对输出电压进行记录。实验中,需要先使用固定电容对此电容传感器进行标定,然后将其应用到微小可变电容的测量中。此实验设计出的电容传感器,其分辨率可高达0.01 fF,等效于差分电容桥的nm级位移。

关键词：桥式电路差分电容相位敏感解调器

Magic on keyboard—CAD in power plant layout

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electricity 1991年第1期 30-33页

作者： Yan Zhisheng Liu Kaihua East china electric power Design institute

The choosing of a good site and the conceiving of a good lay-out are by far the most important features in the engineeringand design of a fossil power plant.A good and well planned site willreduce by million of dollars the cost of construction investment,offuel transportation and waste disposal,of service power and alsopower transmission,*** hence the overall cost of power genera-tion.

关键词： fossil genera layout planned disposal Magic hence transportation viewing frames

Unit 4 of Guddu Thermal power Plant in Pakistan operates successfully A unit supplied by china

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electricity 1990年第2期 48-50页

作者： Lu Pangen North china electric power Design institute Zhang Enli

The Guddu Thermal power Plant of WAPDA is a main fossil powerplant in Pakistan,among which unit 4 with 210 MW in capacity suppliedby china,went into operation in *** 110 MW boiler-turbine-generator units and one 9 MW gas turbine-generator unit of phase Ⅰ projectof the power plant,provided by Skoda Export *** Czechoslovakia,wereput into operation in 1974,while one 210 MW boiler-turbine-generatorunit of phase Ⅱ,provided by the Technical Export Corporation of theSoviet Union,was put into operation in *** the phase Ⅲ,one 210 MW boiler-turbine-generator unit,Which

关键词： boiler turbine Pakistan generator Export fossil supplied steam installed transformer

Shanghai Waigaoqiao power Plant -A New Domestic Engineering, Equipment Supplying, Constructing Large power Plant

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electricity 1996年第2期 32-35页

作者： You Guoming, Shi Jiali, East china electric power Design institute

1.0 Introduction Waigaoqiao power Plant is one of important infrastructure of Shanghai Pudong New Area. The capacity of the first phase project is of 1200 MW, with four (4) domestic made and technology introduced 300 MW coal-fired units. This project was approved by State Planning Commission in April 1990, and also assigned by the Ministry of Energy and Ministry of Machinery

关键词：刀口脚口户口月山山甲阴刀日月山河刀脚刀刃