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Influence of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific on the inter-decadal variations of the stratosphere-troposphere exchange of water vapor

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Science china Earth Sciences 2008年第8期51卷 1179-1193页

作者： ZHAN RuiFen1,2&LI JianPing2 1Shanghai Typhoon Institute of china Meteorological Administration,Shanghai 20003.,china 2state {3. {3. of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG),Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 100029,china Shanghai Typhoon Institute of china Meteorological Administration Shanghai China state key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

This study investigates the Stratosphere-Troposphere Exchange(STE) of water vapor,emphasizes its interdecadal variations over Asia in boreal summer,and discusses the influences of atmospheric heat sources over the Tibetan Plateau and the tropical western North Pacific(WNP) on them by using the Wei method with reanalysis data from the European Centre for Medium-Range weather Forecasts(ECMWF) for the years of *** climatology shows that the upward transport of water vapor across the tropopause in boreal summer is the most robust over the joining area of the South Asian Peninsula and Indian-Pacific Oceans(defined as AIPO).The upward transport over there can persistently convey the abundant water vapor into the stratosphere and then influence the distribution and variation of the stratospheric water *** analysis shows that interdecadal variations of the water vapor exchange over the AIPO are significant,and its abrupt change occurred in the mid-1970s and the early *** these three periods,as important channels of the water vapor exchange,the effect of Bay of Bengal-East Asia as well as South china Sea was gradually weakening,while the role of the WNP becomes more and more *** studies show that atmospheric heat sources over the Tibetan Plateau and the WNP are two main factors in determining the interdecadal variations of water vapor *** thermal influences over the Tibetan Plateau and the WNP have been greatly adjusted over the pass 44 *** synthesis influences the interdecadal variations of the water vapor exchange by changing the Asian summer monsoon,but their roles vary with time and *** after 1992,the influence of heat source over the Tibetan Plateau remarkably weakens,while the heat source over the WNP dominates the across-tropopause water vapor *** have important implications for understanding the transport of other components in the atmosphere and estimating the impact of human activities(

关键词： Tibetan Plateau tropical western North Pacific atmospheric heat source STE inter-decadal variations

A unified dynamic model for locomotion and manipulation of a snake-like robot based on differential geometry

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Science china(Information Sciences) 2011年第2期54卷 318-333页

作者： WANG ZhiFeng1,3. MA ShuGen1,2, LI Bin1 & WANG YueChao1 1state key laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016,{3. 2Department of Robotics, Ritsumeikan University, Shiga-ken 525-8577, Japan 3.raduate University of Chinese Academy of Sciences, {3. 10003.,{3. state key laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang China Graduate University of Chinese Academy of Sciences Beijing China Department of Robotics Ritsumeikan University Shiga-ken Japan

A snake-like robot, whose body is a seried-wound articulated mechanism, can move in various environments. In addition, when one end is fixed on a base, the robot can manipulate objects. A method of dynamic modeling for locomotion and manipulation of the snake-like robot is developed in order to unify the dynamic equations of two states. The transformation from locomotion to manipulation is a mechanism reconfiguration, that is, the robot in locomotion has not a fixed base, but it in manipulation has one. First, a virtual structure method unifies the two states in mechanism (e.g., an embedding in the configuration space); second, the product-of-exponentials formula describes the kinematics; third, the dynamics of locomotion and manipulation are established in a Riemannian manifold; finally, based on the analysis of the dynamic model, the dynamics of manipulation can be directly degenerated from those of locomotion, and this degeneration relation is proved through using the Gauss equations. In the differential geometry formulation, this method realizes the unification of the dynamics of locomotion and manipulation. According to a geometrical point of view, the unified dynamic model for locomotion and manipulation is considered as a submanifold problem endowed with geometric meaning. In addition, the unified model offers an insight into the dynamics of the snake-like robot beyond the dynamic model separately established for locomotion or manipulation.

关键词： snake-like robot dynamics unified model differential geometry locomotion manipulation

Moment tensor analysis of the acoustic emission source in the rock damage process

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Progress in Natural Science:Materials International 2005年第7期15卷 609-613页

作者： YU Huaizhong, ZHU Qingyong, YIN Xiangchu and WANG Yucang ( state key laboratory of Earthquake Dynamics, Institute of Geology,{3. Earthquake Administration, {3. 100029,{3. state key laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, {3. 100080,{3. School of Mathematics and Computational Science, Zhongshan University, Guangzhou 510275,{3. Center for Analysis and Prediction,{3. Seismological Bureau, {3. 10003.,{3. Quakes, Department of Earth Science, University of Queensland, Brishbane, Austrialia) state key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China state key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China School of Mathematics and Computational Science Zhongshan University Guangzhou 510275 China Center for Analysis and Prediction China Seismological Bureau Beijing 100036 China Quakes Department of Earth Science University of Queensland Brishbane Australia

To further investigate the mechanism of acoustic emission (AE) in the rock fracture experiment, moment tensor analysis was carried out. The AE sources characterized by crack sizes, orientations and fracture modes, are represented by a time-dependent moment tensor. Since the waveforms recorded by AE monitors correlate to the moment tensors, we prefer to select the P wave amplitude from the full-space Green's function of homogeneous and isotropic materials to determine the six independent components of the moment tensor. The moment tensor analysis was used to investigate the AE sources recorded in the experiment, and three types of micro-cracks were found, which are tensile mode, shear mode and mixture of the tensile and shear mode. In addition, the motion of micro-cracks was decided by eigenvectors of moment tensor. Results indicate that the moment tensor analysis may be used as a measurement to reflect the damage evolution of rock specimen.

关键词： moment tensor acoustic emission rock fracture.

A local f-x Cadzow method for noise reduction of seismic data obtained in complex formations

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Petroleum Science 2011年第3期8卷 269-277页

作者： Yuan Sanyi Wang Shangxu state key laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China

A noise-reduction method with sliding called the local f-x Cadzow noise-reduction method, windows in the frequency-space （f-x） domain, is presented in this paper. This method is based on the assumption that the signal in each window is linearly predictable in the spatial direction while the random noise is not. For each Toeplitz matrix constructed by constant frequency slice, a singular value decomposition （SVD） is applied to separate signal from noise. To avoid edge artifacts caused by zero percent overlap between windows and to remove more noise, an appropriate overlap is adopted. Besides flat and dipping events, this method can enhance curved and conflicting events. However, it is not suitable for seismic data that contains big spikes or null traces. It is also compared with the SVD, f-x deconvolution, and Cadzow method without windows. The comparison results show that the local Cadzow method performs well in removing random noise and preserving signal. In addition, a real data example proves that it is a potential noise-reduction technique for seismic data obtained in areas of complex formations.

关键词： Cadzow sliding window noise reduction fidelity complex formations Toeplitz matrix,singular value decomposition

Syntheses, structures and magnetic properties of a family of one-dimensional M(Ⅱ)-lanthanide(Ⅲ) (M = Ni(Ⅱ) and Zn(Ⅱ)) coordination polymers

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Science china Chemistry 2007年第3期50卷 308-317页

作者： ZHANG Wen, ZHAO Fei, LIU Tao & GAO Song beijing National laboratory for Molecular Sciences, state {3. laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, beijing 100871, china beijing National laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing China

A series of 1D nickel(II)/zinc(II)-lanthanide(III) coordination polymers, [M(μ-L)2Ln(NO3.3.n·solvents (HL = bis(2-pyridylcarbonyl)amine; M = Ni, Ln = Gd (1·NiGd), Tb (2·NiTb), Dy (3.NiDy), Ho (4·NiHo), Y (5·NiY); M = Zn, Ln = Gd (6·ZnGd), Tb (7·ZnTb), Dy (8·ZnDy), Ho (9·ZnHo); solvents = H2O or H2O-ethanol), was synthesized and characterized. All of the complexes are isostructural at 293.K and crystallize in the orthorhombic space group Fddd. Magnetic measurements were performed on 1―9, where weak ferromagnetic interaction is found in 1·NiGd, ferromagnetic interaction in 2·NiTb and 3.NiDy, and antiferromagnetic interaction in 4·NiHo. A remarkable dc magnetic field dependence of ac susceptibilities was found in this series of complexes.

关键词： nickel lanthanide 3.-4f coordination polymer magnetic property

Optimization of the head shape of the CRH3.high speed train

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Science china(Technological Sciences) 2010年第12期53卷 3356-3364页

作者： SUN ZhenXu1, SONG JingJing1 & AN YiRan1 College of Engineering, state key laboratory for Turbulence and Complex Systems, Peking University, {3. 100871, china College of Engineering State Key Laboratory for Turbulence and Complex Systems Peking University Beijing China

Aiming at optimizing the head shape of the CRH3.high speed train, an efficient optimization approach is proposed. The CFD analysis by solving Navier-Stokes equations is coupled with optimization calculation based on the multi-objective genetic algorithm, meanwhile the arbitrary shape deformation technique (ASD) is also introduced into the design flow, which greatly shortens the time consumption for geometry regeneration and flow field remeshing. As a result, the efficiency of the optimization calculation is highly improved. Statistical analysis is done to the designs in the design space, and the correlation between the design variables and the objective is studied to find out the key variables that most affect the objective. Response surface analysis is also performed to get the nonlinear relationship between the key design variables and the objective with the Kriging algorithm. Finally, after the optimization, an aerodynamic performance comparison between the optimal shape and the original shape reveals that the original shape of CRH3.high speed train owns a very stable aerodynamic performance and can be trustingly used in industry.

关键词： aerodynamic shape design optimization arbitrary shape deformation response surface analysis Kriging algorithm

Syntheses, properties and structures of copper and nickel complexes of 6,7-dihydro-5H-1,4-dithiepin-2,3.dithiolate

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Chinese Journal of Chemistry 1994年第3期12卷 248-257页

作者： YAO, Tian-Ming YOU, Xiao-ZengCoordination Chemistry Institute, state key laboratory of Coordination Chemistry, Nanjing University,Nanjing 210008,{3.YANG, Qing-ChuanChemistry Department, {3. University, {3. 100871,{3. Coordination Chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210008 China Chemistry Department Beijing University Beijing 100871 China

The reaction of CuCl2-2H2O or NiCl2.6H2O with K2(C5H6S4) [potassium salt of 6,7-dihydro-5H-1,4-dithiepin-2,3.dithiolate] under nitrogen atmosphere resulted in the isolation of [Cu(C5H6S4)2]- or [Ni(C5H6S4)2]- as the tetrabutylammonium salt. Both complexes show characteristic IR and UV-Vis absorptions of transition metal dithiolenes. Cyclic voltammograms contain two waves indicating a two step electrochemical procedure [M(C5H6S4)2]0 = [M(C5H6S4)2]1-= [M(C5H6S4)2]2-. Single crystal structure study has been carried out on the nickel complex. Crystal of [Bu4N][Ni(C5H6S4)2] belongs to monoclinic space group P21/c with a=17.576(5), 6=10.883.2), c=17.773.4) A,B=91.07(2)0, Z=4, and o(calcd.)=1.3.8 g/cm3. Final result is R=0.059 for 2959 reflections. The NiS4 core exhibits square planar coordination with average Ni-S bond length of 2.13.(5) A. There are not anion pairs in crystal. The anions stack along a and c axes while the cations intercalate in them. The nearest S-S contact is 4.429 A. The solid powder ESR spectrum of the nickel complex shows three broadening signals at g1=2.097, g2=2.042, g3.2.022. Magnetic susceptibility data for [Bu4N][Ni(CgH6S4)2] reveal enhanced anti-ferromagnetic interaction.

关键词： Dithiolene complex copper nickel single crystal.

Lunar ~3.e estimations and related parameters analyses

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Science china Earth Sciences 2010年第8期53卷 1103-1114页

作者： LI DiHui, LIU HeGuang, ZHANG WeiGuo, LI Yun & XU ChuanDong Center for space Science and Applied Research, Chinese Academy of Sciences, beijing 100190, china Center for space Science and Applied Research Chinese Academy of Sciences Beijing China

As a potential nuclear fuel, 3.e element is significant for both the solution of impending human energy crisis and the conservation of natural environment. Lunar regolith contains abundant and easily extracted 3.e. Based on the analyses of the impact factors of 3.e abundance, here we have compared a few key assessment parameters and approaches used in lunar regolith 3.e reserve estimation and some representative estimation results, and discussed the issues concerned in 3.e abundance variation and 3.e reserve estimation. Our studies suggest that in a range of at least meters deep, 3.e abundance in lunar regolith is homogeneously distributed and generally does not depend on the depth; lunar regolith has long been in a saturation state of 3.e trapped by minerals through chemical bonds, and the temperature fluctuation on the lunar surface exerts little influence on the lattice 3.e abundance. In terms of above conclusions and the newest lunar regolith depth data from the microwave brightness temperature retrieval of the "ChangE-1" Lunar Microwave Sounder, a new 3.e reserve estimation has been presented.

关键词： lunar regolith 3.e abundance reserve estimation maturity granularity composition solar wind flux CELMS

Preparation,Characterization and Applications of Titanate/Titania Nanocrystals

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稀有金属材料与工程 2006年第S3期 638-641页

作者： Junrong Li~(1,2) Zilong Tang~1 Zhongtai Zhang~1 Zhigang Zhou~1 (1.state key laboratory of New Ceramics and Fine Processing,Department of Materials Science and Engineering,Tsinghua University,{3. 100084,china) (2.{3. Institute of space Medico-Engineering,{3. 100094,china)

The present paper focused on the preparation of hydrogen titanate nanotubes and nanowires and their conversion into titania by heat *** structural,morphology and optical properties of as-prepared nanostructured titanate and titania were investigated by transmission electron microscopy (TEM),X-ray diffraction (XRD) and diffusive reflectance *** slim diameter of these nanostructured titanate and titania,the versatile crystal structure and special optical and electronic properties may make them find versatile applications in chemical sensors for multiple purposes.

关键词： titanate titania nanocrystals preparation applications