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The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological Sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2.REN WeiJia1,WANG ShiDa1 & WENG LiJun3.1 Academy of Opto-Electronics,chinese Academy of Sciences,Beijing 100190,china 2.{2. University of chinese Academy of Sciences,Beijing 100049,china 3.Lanzhou Institute of Chemical Physics,chinese Academy of Sciences,Lanzhou 73.000,china 1. Academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

Urban niche dynamics of Kaifeng city

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Journal of Geographical Sciences 2007年第2期17卷 221-233页

作者： Ding Shengyan1, Li Zhiheng1,2.3.1. College of Environment & Planning, Henan University, Kaifeng 475001, china 2. Xishuangbanna Tropical Botanic Garden, CAS, Kunming 6502.3. china 3. {2. school of the chinese Academy of Sciences, Beijing 10003., china College of Environment & Planning Henan University Kaifeng China Xishuangbanna Tropical Botanic Garden CAS Kunming China graduate school of the {2. Academy of Sciences Beijing China

Niche theory is one of the most important ecological theories. It is widely applied to analyzing such phenomena as competition among, and evolution of, urban ecosystem functional modules. This paper describes a study concerning＇different functional modules of Kaifeng city urban ecosystem. Niche theory and techniques were used to analyze the changes of these functional modules in the period 1994-2.03. The results showed that, in the period 1994-2.03. （1） Niche value of the atmospheric environment and urban virescence modules increased, while niche value of the water environment and sound environment modules decreased; （2. niche value of the tertiary industry module increased, niche value of the secondary industry module decreased, while niche value of the primary industry module showed little change; and （3. niche value of the infrastructure, resource distribution, and production ＆ social security modules increased, while niche value of the population module decreased. This study may contribute to macroscopic planning of urban functional modules, economic development, and environmental protection.

关键词： niche pattern functional modules dynamic Kaifeng city

Synthesis of well-defined functional PE graft copoly-mers via ATRP process

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Science Bulletin 2005年第10期50卷 1048-1051页

作者： CAO Chengang1, 2. DONG Jinyong1 & HU Youliang1 1. CAS Key Laboratory of Engineering Plastics, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, chinese Academy of Sciences, Beijing 100080, china {2., chinese Academy of Sciences, Beijing 10003., china CAS Key Laboratory of Engineering Plastics Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China graduate school Chinese Academy of Sciences Beijing 100039 China

In summary, we have demonstrated a convenient yet highly efficient method forthe preparation of PE-based graft copolymers via ATRP.. By introducing a small amount of styrenegroups into PE chains via the selective copolymerization of ethylene with 1,4-divinylbenzenecatalyzed by Et(Ind)_2.rCl_2.MAO, the multifunctional ATRP initiator of1-chloroethylbenzene-containing PE was readily achieved by a quantitative hydrochlorination reactionand was shown to be very effective for the initiation of graft polymerization of MMA and styrene toprepare structurally well-defined PE-based graft copolymers.

关键词： ATRP Synthesis of well-defined functional PE graft copoly-mers via ATRP process PE well

Statistical distribution of nonlinear random wave height

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Science china Earth Sciences 2006年第4期49卷 443-448页

作者： HOU Yijun1, GUO Peifang1,2. SONG Guiting1,2. SONG Jinbao1, YIN Baoshu1 & ZHAO Xixi1,2.1. Institute of Oceanology, {3. Academy of Sciences, Qingdao 2.6071, china 2. {2. University of the {3. Academy of Sciences, Beijing 10003., china 1. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. graduate University of the chinese Academy of Sciences Beijing 100039 China

A statistical model of random wave is developed using Stokes wave theory of water wave dynamics. A new nonlinear probability distribution function of wave height is presented. The results indicate that wave steepness not only could be a parameter of the distribution function of wave height but also could reflect the degree of wave height distribution deviation from the Rayleigh distribution. The new wave height distribution overcomes the problem of Rayleigh distribution that the prediction of big wave is overestimated and the general wave is underestimated. The prediction of small probability wave height value of new distribution is also smaller than that of Rayleigh distribution. Wave height data taken from East china Normal University are used to verify the new distribution. The results in- dicate that the new distribution fits the measurements much better than the Rayleigh distribution.

关键词： Random ocean wave, nonlinearity, wave height distribution.

Tectonic evolution of the Dabieshan orogen: In the view from polyphase deformation of the Beihuaiyang metamorphic zone

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Science china Earth Sciences 2005年第7期48卷 886-899页

作者： LIN Wei1, 2. Faure Michel3. WANG Qingchen1 & Arnaud Nicolas4 1. LTE, Institute of Geology and Geophysics, chinese Academy of Sciences, Beijing 10002.,{3. 2. Department of Earth and Planetary Sciences, {2. school of Science, Nagoya University, Japan 3. ISTO, UMR CNRS 6113. Batiment Géosciences, Orléans Université d’Orléans, 45067 Orléans Cedex 2. France 4. UMR 652. "Magmas et Volcans", 5 Rue Kessler, 63.00 Clermont-Ferrand, France LTE Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Department of Earth and Planetary Sciences Graduate School of Science Nagoya University Japan ISTO UMR CNRS 6113 Orléans Université d'Orléans 45067 Orléans Cedex 2 France UMR 652. Magmas et Volcans 63000 Clermont-Ferrand 5 Rue Kessler France

The Beihuaiyang metamorphic zone was formed by the Early Mesozoic collision of the North and South china Blocks. It consisted of the Foziling and Luzhenguan complexes and was thought to have never afforded a deep subduction. A similar feature of the deformation in the Dabieshan UHP metamorphic rocks implies that these different tectonic units share the same geodynamic background. The early stage of deformation can be preserved on account of their relatively shallower subduction than that for UHP rocks. On the basis of an analysis of the geo- logical structure and geochronological results, five deformational stages have been recognized: a D1-Early compressional deformation which represents the continental subduction; a D2.Early exhumation deformation producing a syn-convergence exhumation; a D3.Main deformation, represented by an exhumation deformation with Late Triassic age; a D4-Doming and its margin extensional gravity collapse deformation and finally a D5-regional extensional deformation of Cretaceous that was mostly introduced by the migmatization and plutonism.

关键词： Beihuaiyang metamorphic zone geometry kinematic polyphase deformation tectonic evolution.

^(13.C NMR spectra of tectonic coals and the effects of stress on structural components

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Science china Earth Sciences 2005年第9期48卷 1418-1437页

作者： JU Yiwen1,2. JIANG Bo1, HOU Quanlin2. WANG Guiliang1 & NI Shanqin2.1. College of Mineral Resource and Geosciences,{3. University of Mining and Technology, Xuzhou 2.1008,{3. 2. Laboratory of Computational Geodynamics, College of Geosciences, {2. school of chinese Academy of Sciences, Beijing 100049,{3. 1. College of Mineral Resource and Geosciences China University of Mining and Technology 221008 Xuzhou China 2. Laboratory of Computational Geodynamics College of Geosciences Graduate School of Chinese Academy of Sciences 100049 Beijing China

High-resolution 13. Nuclear Magnetic Resonance (NMR) spectra of different kinds of tectonic coals were obtained using the NMR (CP/MAS+TOSS) method. On the basis of this, after simulation synthesis and division of spectra, the relative contents of carbon functional groups were calculated. Combined with results of Ro, max, XRD testing and element analysis, stress effects on the composition of macromolecular structures in tectonic coals were studied further. The results showed that Ro, max was not only the important index for describing coal rank, but was also effective for estimating the stress effect of tectonic coals. Under tectonic stress ac- tion, Ro, max was the most direct indicator of the coal structure and chemical components. Changes in the stacking Lc of the coal basic structure unit (BSU) and La/Lc parameters could distinguish the temperature and stress effects on metamorphic-deformed environments, and re- flected the degree of structural deformation. Therefore, on the whole, Lc and La/Lc can be used to index of the degree of structural deformation of tectonic coals. In different metamorphic and de- formed environments, different kinds of tectonic coals are formed under structural stress. The changes in characteristics of the macromolecular structure and chemical composition are such that as the increase in structural deformation becomes stronger, from the brittle deformation coal to ductile deformation coal, the ratio of width at the half height of the aromatic carbon and ali- phatic carbon peaks (Hfa/Hfal ) was increased. As carbon aromaticity was raised further, carbon aliphaticity reduced obviously and different compositions of macromolecular structure appeared as a jump and wave pattern except for in wrinkle structure coal, which might result chiefly from stress effects on the macromolecular structure of different kinds of tectonic coals. The macro- moecular changes of wrinkle structure coal are reflected mainly on physical structure. In the metamorphi

关键词： tectonic coal, NMR, macromolecular structure, chemical component, stress effect.

Development of a Wire Driven Robot for Grinding with Stiffness Adapted

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厦门大学学报（自然科学版） 2002年第S1期41卷 81-82页

作者： ZHANG Bo 1,2. ZHAO Ming-yang 2.(1. graduate {3. of the {2. Academy of Sciences, Beijing 10003. , china 2. Robotics Laboratory, Shenyang Institute of Automation, {2. Academy of S ciences, Shenyang 110016, china)

Along with development of new design and machining me thod production with more complex surface can be manufactured. Researching on th e new equipment used for surface disposal has become the important matter. Grind ing and polishing are a common surface processing method. A new type wire driven parallel robot used for grinding processing is proposed in this paper. Wire driven parallel robot is developed from parallel robot and serial wire driven r obot. Steel wire is used to replace the leg of parallel robot. Compared with par allel robot, this kind of robot has lager workspace, lower weight, higher rigidi ty and higher load/deadweight ratio. And the stiffness of robot is controlled by changing the tension of wire. The robot proposed in this paper has three DOF. T he moving part is driven by four wires, three of them are used to drive and the rest to keep them tension, with a restraining machine. The position sensors are installed in restraining machine. The position of terminating of end-effecter c an be ascertained in the space. The tension sensors are installed in each wire t o form force feedback system. By changing the tension the force on the workpiece can be controlled. Also the stiffness of robot can be adjusted.

关键词： wire driven parallel robot stiffness control

Nonlinear interactions between gravity waves and background winds

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Progress in Natural Science:Materials International 2007年第6期17卷 639-644页

作者： Liu Xiao1,2.and Xu Jiyao1(1. State Key Laboratory for Space Weather, Center for Space Science and Applied Research, chinese Academy of Sciences, Beijing 100080, china 2. {2. University of chinese Academy of Sciences, Beijing 10003., china) [a]State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China [b]graduate University of chinese Academy of Sciences Beijing China

Using the nonlinear propagating gravity waves (GW) model in the two-dimensional compressible atmosphere and the linear GW theory, the process of GW propagation in different background winds, e.g. the direction of the background wind is opposite to (dead wind) or the same as (tail wind) the direction of the horizontal phase velocity of GW, is studied. The results show that the dead wind prolongs the vertical wavelength and accelerates GW propagation. Therefore, GW propagates up to a higher height becomes instable in a short time and eventually induces an inverse jet flow. Then, the vertical wavelength is becoming short due to the nonlinear interactions between GW and the inverse jet flow. The vertical wavelength and group velocity decrease after GW propagates into the tail wind. The initial instable time is delayed. Although most of GW is trapped in the instable region, some of GW propagates above the instable region. Compared with GW propagation in the tail wind, the nonlinear interactions between GW and the dead wind are also strong. In contrast, the linear GW theory predicts that GW can propagate freely in the dead wind. The vertical wavelength simulated by the nonlinear numerical model is different from that predicted by the linear theory greatly after GW propagates into the dead wind.

关键词： gravity waves background winds vertical group velocity vertical wavelength nonlinear interactions.

New synthesis of amphiphilic copolymers PE-g-PEO via esterfication

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chinese Science Bulletin 2003年第6期48卷 523-525页

作者： L?Yingying1, MA Zhi1,2. HU Youliang1, XU G. X.3.& CHUNG T. C.3.1. State Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, chinese Academy of Sciences, Bei-jing Beijing Lab of Catalysis, Key Lab of Catalysis of china Na-tional Petroleum Corporation, Beijing 100080, china 2. graduate school of chinese Academy of Sciences, Beijing 10003., china 3. Department of Material Science and Engineering, Pennsylvania State University, University Park, PA 16802. USA State Key Laboratory of Engineering Plastics Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing Beijing Lab of Catalysis Key Lab of Catalysis of China National Petroleum Corporation Beijing China graduate school of {2. Academy of Sciences Beijing China Department of Material Science and Engineering Pennsylvania State University PA USA

A new series of high molecular weight amphi-philic graft copolymers PE-g-PEO has been prepared. The esterifications between PE-p-MS-g-MA and PEO with OH group at the chain end are carried out under different condi-tions. The compositions of these graft copolymers are studied by NMR and FTIR. It is found to be a convenient and effi-cient way to prepare high molecular weight PE-g-PEO graft copolymers.

关键词：聚乙烯聚(乙烯氧化物) 酯化反应合成方法亲油亲水两性片断共聚物 PE-g-PEO