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稀有金属材料与工程 2012年第S1期41卷 344-349页

作者： Guo Chun1,2.Chen Jianmin1,Zhou Jiansong1,Zhao Jierong1,2.Wang Lingqian1,2.Yu Youjun1,2.Zhou Huidi 1 1 Lanzhou Institute of Chemical Physics,chinese academy of {2.,Lanzhou 730000,china 2.graduate University of chinese academy of sciences,Beijing 100039,china chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China chinese Acad Sci Grad Univ Beijing 100039 Peoples R China

TiB2.TiB/TiNx(x=1,0.3)/Ti composite coating was prepared on pure Ti by laser surface alloying by using powders of boron as starting *** composite coating was examined by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM)and scanning electron microscopy(SEM).The friction and wear properties of the composite coating were examined using a pin-on-disk tester under dry sliding wear *** results showed that the top surface of the composite coating was mainly composed of TiB2.TiB,TiN0.3,TiN and Ti phases,while the interface of the composite coating was composed of TiB and Ti *** composite coating showed sticklike structure near the top surface,and dendrites structure near the *** friction and wear test showed that the composite coating had better wear resistance than pure Ti due to their higher microhardness than that of pure Ti substrate.

关键词： pure Ti laser surface alloying TiB2 composite coating friction and wear property

On the Laws and Causes of Socio-economic Territorial Differentiation in Minority Areas in china

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chinese Journal of Population,Resources and Environment 2009年第1期7卷 30-36页

作者： Xue Mei Dong Suocheng Institute of Geographical Science and Resource Research Chinese Academy of Sciences Beijing 100101 China graduate University Chinese Academy of Sciences Beijing 100039 China

On the basis of applying quantitative and qualitative approaches as well as GIS technology, this paper established an index system to make a comprehensive evaluation on socio-economic development of minority areas in china. The result showed that socio-economic development in minority area presents a series of characteristics that the north is high and the south is low, center-margin pattern is obvious and the areas with middle and lower development indices are distributed centrally and continuously. However, the causes of the socio-economic characteristics mainly include natural conditions, economic development basic, population cultural quality, re-gional combination and development conditions of mineral and energy resources, informal institutional factors and distribution of major traffic lines..

关键词： minority areas socio-economic development laws of territorial differentiation

Applications of URANS on predicting unsteady turbulent separated flows

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Acta Mechanica Sinica 2009年第3期25卷 319-324页

作者： Jinglei Xu Huiyang Ma Department of Physics, graduate University of the chinese academy of sciences, 100049 Beijing,{2. Department of Physics Graduate University of the Chinese Academy of Sciences 100049 Beijing China

Accurate prediction of unsteady separated turbulent flows remains one of the toughest tasks and a practi cal challenge for turbulence modeling. In this paper, a 2. flow past a circular cylinder at Reynolds number 3,900 is numerically investigated by using the technique of unsteady RANS （URANS）. Some typical linear and nonlinear eddy viscosity turbulence models （LEVM and NLEVM） and a quadratic explicit algebraic stress model （EASM） are evaluated. Numerical results have shown that a high-performance cubic NLEVM, such as CLS, are superior to the others in simulating turbulent separated flows with unsteady vortex shedding.

关键词： URANS Nonlinear eddy viscosity turbulencemodel ,Separated flows Circular cylinder

Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan University Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. LIU Chuang1, 3 1. Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101,{2. 2. graduate University of chinese academy of sciences, Beijing 100049,{2. 3. College of Resources Science and Technology, Beijing Normal University, Beijing 100875,{2. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate University of chinese academy of sciences Beijing China College of Resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993,the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the china-Brazil earth resources satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993 to 2.08. There were 12.637.54 hm2.cropland de-creased between 1993 and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the china-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

Twistor bundle theory and its application

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Science china Mathematics 2004年第4期47卷 605-616页

作者： PENG Chia-Kuei & TANG ZizhouDepartment of Mathematics, graduate school of{2., Beijing 100039, china Department of Mathematical sciences, Tsinghua University, Beijing 100084, china 1. Department of Mathematics Graduate School of Chinese Academy of Sciences 100039 Beijing China 2. Department of Mathematical sciences Tsinghua University 100084 Beijing China

Over an oriented even dimensional Riemannian manifold(M 2. ,ds2.), in terms of the Levi-Civita connection form Ω and the canonical form Θ on the bundle of positive orthonormal frames, we give a detailed description of the twistor bundle Гm = SO(2.)/U(m)? J +(@#@ M,ds2.) →M. The integrability on an almost complex structureJ compatible with the metric and the orientation, is shown to be equivalent to the fact that the corresponding cross section of the twistor bundle is holomorphic with respect toJ and the canonical almost complex structureJ 1 onJ +(M,ds2.), by using moving frame theory. Moreover, for various metrics and a fixed orientation onM, a canonical bundle isomorphism is established. As a consequence, we generalize a celebrated theorem of LeBrun.

关键词： almost complex structure, integrability, twistor bundle.

The effects of centrally administered fluorocitrate via inhibiting glial cells on working memory in rats

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Science china(Life sciences) 2009年第8期52卷 701-709页

作者： WANG Lei1,2.LI Chao-Cui1,WANG Gong-Wu1 & CAI Jing-Xia1 1 Section of Brain and Behavior,Kunming Institute of Zoology,the chinese academy of sciences,Kunming 6502.3,china 2.{2. school of the chinese academy of sciences,Beijing 100049,china 1. Section of Brain and Behavior Kunming Institute of Zoology the Chinese Academy of Sciences Kunming 650223 China 2. graduate school of the chinese academy of sciences Beijing 100049 China

Although prefrontal and hippocampal neurons are critical for spatial working memory,the function of glial cells in spatial working memory remains *** this study we investigated the function of glial cells in rats' working *** glial cells of rat brain were inhibited by intracerebroventricular(icv) injection of fluorocitrate(FC).The effects of FC on the glial cells were examined by using electroencephalogram(EEG) recordings and delayed spatial alternation *** icv injection of 10 μL of 0.5 nmol/L or 5 nmol/L FC,the EEG power spectrum recorded from the hippocampus increased,but the power spectrum for the prefrontal cortex did not change,and working memory was *** an icv injection of 10 μL of 2. nmol/L FC,the EEG power spectra in both the prefrontal cortex and the hippocampus increased,and working memory *** icv injection of 10 μL of 50 nmol/L FC,the EEG power spectra in both the prefrontal cortex and in the hippocampus decreased,and working memory was *** results suggest that spatial working memory is affected by centrally administered FC,but only if there are changes in the EEG power spectrum in the prefrontal ***,the prefrontal glial cells relate to the working memory.

关键词： glial cell fluorocitrate prefrontal cortex hippocampus electroencephalogram power spectrum spatial working memory

An Efficient High-Resolution Shock-Capturing Scheme for Multi-Dimensional Flows I. Hydrodynamics

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chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 680-688页

作者： Cong Yu National Astronomical Observatories / Yunnan Astronomical Observatory, chinese academy of sciences, Kunming 650011 graduate {2. of chinese academy of sciences, Beijing 100049 graduate school of{2. Beijing 100049

Many problems at the forefront of theoretical astrophysics require a treatment of dynamical fluid behavior. We present an efficient high-resolution shock-capturing hydrodynamic scheme designed to study such phenomena. We have implemented a weighted, essentially non-oscillatory （WENO） scheme to fifth order accuracy in space, lILLE approximate Riemann solver is used for the flux computation at cell interface, which does not require spectral decomposition into characteristic waves and so is computationally friendly. For time integration we apply a third order total variation diminishing （TVD） Runge-Kutta scheme. Extensive testing and comparison with schemes that *** characteristic decomposition are carried out demonstrating the ability of our scheme to address challenging open questions in astrophysics.

关键词： accretion - hydrodynamics- method numerical - shock waves

Nonculturability of the pathogenic Vibrio parahaemolyticus in live culture of Grateloupia turuturu is associated with bacterial attachment to the algal thalli

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Acta Oceanologica Sinica 2010年第6期29卷 92-103页

作者： LIU Feng PANG Shaojun Marine Biological Culture Collection Centre Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate University of chinese academy of sciences Beijing 100049 China

The invasive red alga Grateloupia turuturu Yamada could turn Vibrio parahaemolyticus into nonculturable state in live algal *** order to elucidate the mechanism of such an effect,a series of culture experiments were performed in this investigation based on three hypothesized causes,namely bacterial attachment,production of reactive oxygen species （ROS） and the discharge of water soluble secondary metabolic *** results reveal that attachment to the thallus surface of *** was the major reason for the decrease of *** in *** investigations show that *** attachment to the surface of algal thallus in live cultures of seaweeds was a common ***,the disappearance of the culturability of *** occurred only on the thallus of *** over 72.h among all six algal species *** microscopic scanning shows that most of *** attached to *** changed from the initial normal bacilli to coccoid-shape after 72.*** enclosure experiments by enclosing the algal thallus in tubes demonstrate that the nonculturability of *** in the water of live culture of *** occurred after the physical contact of the *** to the *** capacity of *** in affecting the culturability of *** was not influenced after inhibition of photosynthesis by treatment of 3（3,4dichlorophenyl）-1 ,1dimethyl urea （DCMU） at non-lethal *** of reactive oxygen species after addition of live culture of bacteria was excluded by on-line analyzing the oxidation of dichlorohydrofluorescein （DCFH） to dichlorofluorescein （DCF） in the presence of peroxidase on a VersaFluor fluorometer.

关键词： Grateloupia turuturu attachment Vibrio parahaemolyticus nonculturability effective quantum yield

Forecasting the summer rainfall in North china using the year-to-year increment approach

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Science china Earth sciences 2009年第4期52卷 532-539页

作者： FAN Ke1, LIN MeiJing1,2.& GAO YuZhong3 1 Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of sciences, Beijing 10002., china 2.{2. University of the chinese academy of sciences, Beijing 100049, china 3 Heilongjiang Meteorological Administration, Harbin 150030, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China graduate University of the chinese academy of sciences Beijing 100049 China Heilongjiang Meteorological Administ

A new approach to forecasting the year-to-year increment of rainfall in North china in July-August (JA) is proposed. DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). NR denotes the seasonal mean precipitation rate over North china in JA. After analyzing the atmospheric circulation anomalies associated with the DY of NR, five key predictors for the DY of NR have been identified. The prediction model for the DY of NR is established by using multi-linear regression method and the NR is obtained (the current forecasted DY of NR added to the preceding observed NR). The prediction model shows a high correlation coefficient (0.8) between the simulated and the observed DY of NR throughout period 1965-1999, with an average relative root mean square error of 19% for the percentage of precipitation rate anomaly over North china. The prediction model makes a hindcast for 2.00-2.07, with an average relative root mean square error of 2.% for the percentage of precipitation rate anomaly over North china. The model reproduces the downward trend of the percentage of precipitation rate anomaly over North china during 1965-2.06. Because the current operational prediction models of the summer precipitation have average forecast scores of 60%-70%, it has been more difficult to forecast the summer rainfall over North china. Thus this new approach for predicting the year-to-year increment of the summer precipitation (and hence the summer precipitation itself) has the potential to significantly improve operational forecasting skill for summer precipitation.

关键词： annual increment North china precipitation prediction prediction skill

Sea level variations in the South china Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science china Earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3 & XU HouZe 1,3 1 State Key Laboratory of Geodesy and Earth’s Dynamics,Institute of Geodesy and Geophysics,chinese academy of {2.,Wuhan 430077,china 2.graduate University of chinese academy of sciences,Beijing 100049,china 3 Institute of Geophysics,Huazhong University of Science and Technology,Wuhan 430074,china 1. State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Geophysics Huazhong University of Science and Technology Wuhan 430074 China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South china Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3 cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993-2.09,which is significantly higher than the global sea level rise rate of 3.3±0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South china Sea sea level variation