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INFLUENCES ON COUPLED LATERAL AND TORSION VIBRATION BEHAVIOR OF RUB-IMPACT ROTOR BY ROTOR-TO-STATOR CLEARANCE

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Chinese Journal of Mechanical engineering 2004年第2期17卷 210-214页

作者： Gu Yujiong He Chengbing Yang Kun Zhang Jianqiang Department of power engineering,north{3. electric power university,Beijing 102206,{3. 华北电力大学（北京）北京 102206

With the establishment of the nonlinear coupled lateral and torsion vibrationequations of rub-impact Jeffcott rotor and through numerical simulations, the influences on lateraland torsion vibration behavior by rotor-to-stator clearance are analyzed, which prove that there isstrong impact on coupled lateral and torsion vibration behavior. Smaller the clearance is, morecomplex the motion of rotor is. When the clearance is larger, the frequency spectrum of rub-impactrotor is mainly composed of 1/2X, 1/3. and 1/4X components. With the decrease of clearance,quasi-periodic and chaotic motions will be present. Under different clearances, the bifurcationdiagrams of lateral and torsion vibrations can be divided into rub-free zone, rub-light zone andthree complex motion zones in which the motion trend of lateral vibration is similar to that of thetorsion vibration. Compared with the lateral vibration, the torsion vibration is of more motionforms and more abundant frequency components in amplitude spectrum.

关键词： Rub-impact rotor Rotor-to-stator clearance Coupled lateral and torsionvibrations

Thresholds of geographic environmental elements in sediment yield of drainage basins

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science china Earth sciences 2005年第2期48卷 230-240页

作者： CHEN Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101,{3. institute of Forestry science, Chinese Academy of Forestry science, Beijing 100091,{3. Research Center for Eco-Environment sciences, Chinese Academy of sciences, Beijing 100085,{3. computing institute of science and engineering, north china electric power university, Beijing {13.,{3. 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. institute of Forestry science Chinese Academy of Forestry Science 100091 Beijing China 3. Research Center for Eco-Environment sciences Chinese Academy of Sciences 100085 Beijing China 4. computing institute of science and engineering North China Electric Power University 102206 Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

Mission planning of the flying robot for powerline inspection

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Progress in Natural science:Materials International 2009年第10期19卷 1357-1363页

作者： Chang’an Liu,Lei Wang,Chunyang Liu School of Computer science and Technology,north china {3. power university,Beijing 102206,china [a]School of Computer science and Technology North China Electric Power University Beijing 102206 China

Mission planning is an important step in the powerline inspection flying *** deal with the tasks of powerline flying robots,a flying robot mission-planning system is established based on the unmanned mini-helicopter model described in this *** can deter-mine the best checking order,the optimal space path and the best flight *** objective function and the constraints are described by establishing the mathematical model,and the mission-planning system is decomposed by using the tiered ***-agent technology is chosen to solve the mission-planning ***,simulation is conducted to verify that the mission-planning system is feasible and efficient.

关键词： powerline inspection flying robot Mission planning Multi-agent technology

A cross-association model for CO_2-methanol and CO_2-ethanol mixtures

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science china Chemistry 2010年第6期53卷 1438-1444页

作者： FU Dong,YANG Zhuang,LU JianYi & LIU JianMin School of Environmental science and engineering,north{3. electric power university,Baoding 071003.china 1. School of Environmental science and engineering North China Electric Power University Baoding 071003 China

A cross-association model was proposed for CO2-alcohol mixtures based on the statistical associating fluid theory (SAFT).CO2 was treated as a pseudo-associating molecule and both the self-association between alcohol hydroxyls and the cross-association between CO2 and alcohol hydroxyls were *** equilibrium properties from low temperature-pressure to high temperature-pressure were investigated using this *** calculated p-x and p-p diagrams of CO2-methanol and CO2-ethanol mixtures agreed with the experimental *** results showed that when the cross-association was taken into account for Helmholtz free energy,the calculated equilibrium properties could be significantly improved,and the error prediction of the three phase equilibria and triple points in low temperature regions could be avoided.

关键词： CO2-methanol CO2-ethanol cross-association SAFT phase equilibria

Experiments and reaction characteristics of liquid phase simultaneous removal of SO_2 and NO

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science china(Technological sciences) 2009年第6期52卷 1768-1775页

作者： ZHAO Yi,LIU Feng,GUO TianXiang & ZHAO Yin School of Environmental science and engineering,north{3. electric power university,Baoding 071003.china 1. School of Environmental science and engineering North China Electric Power University Baoding 071003 China

Experiments of simultaneous removal of SO2 and NO from simulated flue gas,using NaClO2 solution as the absorbent,were carried out in a self-designed bubble reactor,and high simultaneous removal effi-ciencies of SO2 and NO were obtained under the optimal experimental *** mechanism of simultaneous removal based on NaClO2 acid solutions was proposed by analyzing the removal *** and limitation of the desulfurization and denitrification using NaClO2 acid solutions were calculated by thermodynamic *** results of reaction kinetics for simultaneous desulfurization and denitrification indicated that the oxidation-absorption processes of SO2 and NO were divided into two zones,namely the fast and slow reaction *** the slow reaction zones both were zero order reactions,and in the fast reaction zones,the reaction order,rate constant and activa-tion energy of SO2 reaction with absorbent were 1.4,1.22(mol.L-1)-0.4.s-1 and ***-1,respec-tively,and 2,3.15×103.mol.L-1)-1.s-1,and 42.50 ***-1 for NO reaction,respectively.

关键词： sodium chlorite simultaneous removal of SO2 and NO kinetics experiments

Current distribution and stability of LTS/HTS hybrid superconducting conductors

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science china(Technological sciences) 2010年第7期53卷 2000-2007页

作者： GUAN XiaoJin1,2, WANG YinShun1 & ZHOU WeiWei3.1 Key Laboratory of HV and EMC Beijing, north china electric power university, Beijing 102206, china 2 Department of Physics, Baoding {3., Baoding 071000, china 3.institute of electrical engineering, Chinese Academy of sciences, Beijing 100190, china 1. Key Laboratory of HV and EMC Beijing North China Electric Power University Beijing 102206 China2. Department of Physics Baoding University Baoding 071000 China3. Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China

Current distribution and stability of a hybrid LTS/HTS superconductor, consisting of multifilamentary NbTi/Cu and Bi2223.Ag tapes, were numerically analyzed according to power-law models. The results showed that most of current passed through the LTS and the current increased in the HTS with temperature rise when the transport current was below the critical current of the hybrid conductor. The quench propagation velocity of the hybrid conductor was smaller but its minimum quench energy was larger than those of LTS conductors, indicating that the stability of the hybrid superconducting conductor was effectively improved and a high engineering current density was simultaneously achieved. Finally, a hybrid sample, made by soldering Bi2223.Ag tape onto NbTi/Cu conductor, was prepared and tested successfully at helium temperature. The experimental results qualitatively agreed with the simulated ones.

关键词： distribution hybrid conductor minimum quench energy quench propagation velocity n value stability

Some invariant properties of ordered information systems under homomorphism

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science china(Information sciences) 2010年第9期53卷 1816-1825页

作者： WANG ChangZhong1*,CHEN DeGang2 & HU QingHua3.1Department of Mathematics,Bohai university,Jinzhou 121000,china 2Department of Mathematics and Physics,north{3. electric power university,Beijing 102206,china 3.5} engineering,Harbin institute of Technology,Harbin 150001,china 1. Department of Mathematics Bohai University Jinzhou 121000 China2. Department of Mathematics and Physics North China Electric Power University Beijing 102206 China3. Power Engineering Harbin Institute of Technology Harbin 150001 China

In this paper,some properties of ordered information systems under homomorphism are *** concept of a consistent function with respect to dominance relations is first introduced and its properties are ***,some main invariant properties of dominance relations under relation mappings are *** is proven that attribute reductions in the original ordered information system and its image system are equivalent under the condition of *** means of the results,we can get the smaller image system that has the same reducts as a given massive ordered information system.

关键词： consistent function dominance relation ordered information system homomorphism reduction

Study on method and mechanism for simultaneous desulfurization and denitrification of flue gas based on the TiO_2 photocatalysis

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science china(Technological sciences) 2008年第3期51卷 268-276页

作者： ZHAO Yi, ZHAO Li, HAN Jing, XU YongYi & WANG ShuQin School of Environmental science & engineering, north china electric power university, Baoding 071003.{3. 1. School of Environmental science & engineering North China Electric Power University Baoding 071003 China

Based on the TiO2 photocatalysis mechanism, a new method of simultaneous desulfurization and denitrification from flue gas was proposed. Preparation of TiO2 photocatalyst, design of photocatalysis reactor and influencing factors for simul- taneous removal of SO2 and NO, and removal mechanism of SO2 and NO were studied. After the optimal values of concentration of O2 in flue gas, the relative humidity of flue gas and the irradiation time in the photocatalysis reactor were used, the efficiencies of removal for SO2 and NO can be achieved above 98% and about 67%, respectively. According to the results of removal products analysis, the re- moval mechanism of SO2 and NO based on TiO2 photocatlysis can be put forward, namely, SO2 was oxidized to SO3.partly, the bulk of NO was oxidized to NO2, and both were removed by resorbing finally.

关键词： TiO2 photocatalysis flue gas simultaneous desulfurization and denitrification reaction mechanism

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.{3. 2 School of Renewable Energy engineering,north china electric power university,Beijing 102206,{3. 3.National Laboratory of Micro-Gravity,institute of Mechanics,Chinese Academy of sciences,Beijing 100080,{3. 1. Key Laboratory of Semiconductor Materials science Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China2. School of Renewable Energy Engineering North China Electric Power University Beijing 102206 China3. National Laboratory of Micro-Gravity Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

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