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Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2, GU Yidong3. LIN Baojun3.& GUO Jiong3.1. center for Space Science and Applied research, chinese academy of sciences, Beijing 100080,{3. 2. Graduate School of the chinese academy of sciences, Beijing 10003.,{3. 3. General Establishment of Space Science and Application, chinese academy of sciences, Beijing 100080,{3. Correspondence should be addressed to L Congmin 1. center for Space Science and Applied research Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. General Establishment of Space Science and Application Chinese Academy of Sciences 100080 Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2 m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

Simulation of Isotopic Angular Effects under Ion Bombardment of a^(92)Mo-^(100)Mo Target

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Journal of Materials Science & Technology 1997年第1期13卷 65-68页

作者： Liping ZHENG (shanghai Institute of Nuclear research, chinese academy of sciences, shanghai 201800, china)Risheng LI and Shuyou LI(Lab. of Atomic Imaging of Solids, Institute of Metal research, chinese academy of sciences,Shenyang 110015, china) shanghai Institute of Nuclear research Chinese Academy of Sciences Shanghai 201800 China Lab. of Atomic Imaging of Solids Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Under 5 keV Ar ion bombardment of a 92Mo-100Mo target, we have investigated isotopic angular effects by means of the static and the dynamic Monte Carlo programs. Our calculated results are in quantitative agreement with the measured and other calculated results. The conclusion consistences among theories. simulations and measurements are also discussed.

关键词： Mo Target Simulation of Isotopic Angular Effects under Ion Bombardment of a Target

Organic Solvents Mediate Self-assembly of GAV-9 Peptide on Mica Surface

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Acta Biochimica et Biophysica Sinica 2007年第4期39卷 285-289页

作者： Hai LI~(1,3. Feng ZHANG~1 Yi ZHANG~1* Jianhua HE~1 Jun HU~(1,2) 1 shanghai Institute of Applied Physics,chinese academy of {3.,shanghai 201800,china 2 Bio-X Life {3. research center.College of Life Science and Biotechnology,shanghai Jiaotong University,shanghai 20003.,china 3.Graduate School of the{13.,Beijing 100049,china shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800 China Graduate School of the chinese academy of sciencesBeijing 100049 China Bio-X Life sciences research center College of Life Science and Biotechnology Shanghai Jiaotong UniversityShanghai 200030 China

Self-assembly of peptides into fibrils and other morphologies has attracted much attention inmany fields,especially in nanofabrication,pathology and *** this paper,self-assembly of GAV-9peptide in organic solvents,ethanol and acetone,was investigated using atomic force microscopy(AFM)and attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR).The results indicatedthat GAV-9 self-assembled into various nanostructures in both solvents after deposited and evaporated *** with β-sheet conformation were observed in both solvents when the peptide concentrationwas higher than 280 μ***,ordered fibrils with β-sheet conformation were formed in ethanol,butnot in acetone,with a peptide concentration ranging from 7 μM to 28 μ*** attribute the formation ofvarious nanostructures to the different physicochemical properties of the polar organic solvents on the self-assembly of GAV-9 peptide.

关键词： self-assembly GAV-9 peptide organic solvents ATR-FTIR AFM

Entropy of three-dimensional BTZ black holes

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中国科学：物理学、力学、天文学英文版 2004年第3期47卷 277-283页

作者： GAO Changjun1,2 & SHEN Yougen1,2,3.4 1.shanghai astronomical Observatory,chinese {3. of sciences,shanghai 20003.,china(mailing address) 2.National astronomical Observatories,chinese {3. of sciences,Beijing 100012,china 3.Institute of Theoretical Physics,chinese {3. of sciences,Beijing 100080,china 4.shanghai united center for astrophysics,shanghai 20023.,china 1. shanghai astronomical Observatory Chinese Academy of Sciences 200030 Shanghai China 2. National astronomical Observatories Chinese Academy of Sciences 100012 Beijing China 3. Institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China 4. shanghai united center for {3.physics 200234 Shanghai China

The entropies of scalar field and neutrino field are calculated in the background of three-dimensional BTZ black hole. Considering statistical physics,we propose not to consider the superraradiant modes for bosons (Fermion fields do not display supperradiance).In fact,the nonsuperradiant modes do contribute exactly the area entropy for both bosons and fermions. The result shows that the neutrino field entropy is 3.2 times the scalar one.

关键词： BTZ black holes, entropy, supperradiant modes.

miRNAs modulate the drug response of tumor cells

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Science china(Life sciences) 2009年第9期52卷 797-801页

作者： WU XueMei1,3.& XIAO HuaSheng1,2 1 center of Functional Genomics,Key Laboratory of System Biology,shanghai Institutes for Biological sciences,{3. academy of sciences,shanghai 20003.,china 2 National Engineering center for Biochip at shanghai,shanghai 201203.china 3.Graduate University of{13.,shanghai 20003.,china center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China National Engineering center for Biochip at shanghai Shanghai 201203 China Graduate University of chinese academy of sciences Shanghai 200031 China

Chemotherapy is one of the major treatments of malignant carcinomas. However,its efficiency is affected by both intrinsic and acquired resistance to anticancer drugs. The cellular mechanisms of drug resistance include the overexpression of energy-dependent transporters that eject anticancer drugs from cells such as p-glycoprotein and multidrug resistance related protein (MRP),the mutation of drug targets,the activation of DNA repair pathways,the defects in cellular death pathways and so on. The genetic and epigenetic changes of these genes can lead to cancer drug resistance. Among these mechanisms,microRNAs (miRNAs) which are critical and essential for many important processes such as development,differentiation,and even carcinogenesis have been reported to regulate the chemosen-sitivity of tumor cells. In this paper we briefly review the relationship between miRNA and cancer drug resistance.

关键词： cancer drug resistance miRNAs

Orbit determination and prediction accuracy analysis for a regional tracking network

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Science china(Physics,Mechanics & astronomy) 2010年第6期53卷 1130-1138页

作者： ZHOU ShanShi 1,2,3.,HU XiaoGong 1 & WU Bin 1 1 shanghai astronomical Observatory,chinese {3. of sciences,shanghai 20003.,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3.research center of GNSS,Wuhan 43.079,china 1. shanghai astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Research Center of GNSS Wuhan 430079 China

china's COMPASS satellite navigation system relies on a regional tracking network to provide navigation services. Limited by its geographic border,the regional network is able to cover only 3.% of the medium-earth-orbits(MEO). Accuracy of determined and predicted orbits is not able to satisfy system requirements if the tracking data processing strategy for global tracking network processing is used for the regional network. Two major error sources for orbital prediction are accuracy of initial orbital elements and dynamical modeling. To achieve better prediction accuracy,we propose a two-step orbit determination and prediction strategy. For step 1,only solar radiation pressure(SRP) parameters are estimated along with the orbital elements and other parameters; for step 2,all parameters are estimated but the SRP parameters are tightly constrained to their step 1 estimates. Experimenting with data from a regional GPS network,we conclude for orbital prediction using the proposed two-step strategy,the average user range error(URE) for 24-h prediction arcs is better than 0.6 m.

关键词： orbit determination and prediction regional tracking network URE

Removal Behaviors of Different SiC Ceramics during Polishing

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Journal of Materials Science & Technology 2010年第2期26卷 125-130页

作者： Guiling Liu, Zhengren Huang , Xuejian Liu and Dongliang Jiang Structural Ceramics center, shanghai Institute of Ceramics, chinese academy of sciences, shanghai 200050, china [a] Structural Ceramics center shanghai Institute of Ceramics chinese academy of sciences shanghai 200050 china

Comparative experiments were conducted to reveal the removal behaviors of three kinds of silicon carbide （SIC） ceramics during polishing and the effects of ceramic microstructure on the surface quality were also reported. Experimental results show that the second phase in SiC ceramics plays an important role in the surface quality when its size is large enough. The surface quality is enslaved to the formation of steps at interfaces between second phase and SiC matrix that results from different elastic modulus and hardness between two phases. Under 3.μm abrasive grains polishing condition, different SiC ceramics show different removal mechanisms. With decreasing abrasive grain size, all of different SiC ceramics exhibit a ductile removal mode, which decreases surface roughness efficiently.

关键词： SiC Surface quality Removal behavior Polishing

Single crystal β-Ga_2O_3. Cr grown by floating zone technique and its optical properties

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Science china(Technological sciences) 2007年第1期50卷 51-56页

作者： ZHANG JunGang1, 2, LI Bin3. XIA ChangTai1, XU Jun1, DENG Qun4, XU XiaoDong1, WU Feng1, XU WuSheng4, SHI HongSheng4, PEI GuangQing1, 2 & WU YongQing1,2 1 shanghai Institute of Optics and Fine Mechanics, chinese academy of sciences, shanghai 201800,{3. 2 Graduate School of the chinese academy of sciences, Beijing 10003.,{3. 3.shanghai Institute of Applied Physics, chinese academy of sciences, shanghai 201800,{3. 4 GE (china) research and Development center Co. Ltd., shanghai 201203.{3. 1. shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China 3. shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 4. GE (china) research and Development center Co. Ltd. Shanghai 201203 China

β-Ga2O3. Cr single crystals were grown by floating zone technique. Absorption spectra and fluorescence spectra were measured at room temperature. The values of field splitting parameter Dq and Racah parameter B were obtained by the peak values of absorption spectra. The value 10Dq/B=23.14 manifests that in β-Ga2O3.crystals Cr3. ions are influenced by low energy crystal field. After high temperature annealing in air, the Cr3. intrinsic emission was enhanced and the green lumines-cence disappeared. The strong and broad 691 nm emission was obtained at 420 nm excitation due to the electron transition occurred from 4T2 to 4A2. The studies manifest that the β-Ga2O3.crystals have the potential application for tunable laser.

关键词： β-Ga2O3. Cr single crystals floating zone technique tunable laser spectrum.

Plumb line variation at Tangshan during 1987―1998 and its relation with the earthquakes around

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Science china Earth sciences 2009年第1期52卷 101-107页

作者： LI ZhengXin1,2 & LI Hui3.1 shanghai Observatory,chinese academy of {3.,shanghai 20003.,china 2 Institute of Geodesy and Geophysics,chinese academy of {3.,Wuchang 43.077,china 3.Institute of Seismology,china Earthquake Administration,Wuchang 43.071,china shanghai Observatory Chinese Academy of Sciences Shanghai 200030 China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuchang 430077 China Institute of Seismology China Earthquake Administration Wuchang 430071 Chin

Plumb line variations(PLV) at Tangshan during the years of 1987―1998 are determined by using the 46 batch repeated gravity observations of the Beijing-Tangshan *** has been found that PLV at Tangshan are related with the 3. earthquakes in this *** appears that the time of an earthquake around Tangshan is usually quite the same when PLV at Tangshan begins moving in opposite direction.

关键词： plumb line variations network in northern china variations of local gravity field earthquakes