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Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

Science China Earth sciences 2006年第9期49卷 991-1001页

作者： WU Yanhong1, WANG Sumin1& HOU Xinhua1,3 1. Key Laboratory of Lake Sedimentation and Environment, Nanjing Institute of Geography and Limnology, chinese academy of {2., Nanjing 2.0008, China 2. Institute of Tibetan Plateau Research, chinese academy of {2., Beijing 10085, China 3. graduate university of chinese academy of {2., Beijing 100039, China 1. Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 2. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 10085 China 3. graduate university of {2. academy of {4. Beijing 100039 China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14., 2.0Pb and 137Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14. age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 2.0Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14. dating is stronger. Based on the analysis on results of 14., 2.0Pb and 137Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14. calendar ages, and establish the time sequence for cores CE-1 and CE-2.with result of 2.0Pb CRS model for the upper 35 cm and re-calculated 14. calendar age for sediments bellow 35 cm. Since 14.0 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14., 2.0Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

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Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of Atmospheric sciences, Lanzhou university, Lanzhou 730000, China 2. LASG, Institute of Atmospheric Physics, {2. academy of sciences, Beijing 10002., China) College of Atmospheric sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 194.—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

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The correspondence between the concepts in description logics for contexts and formal concept analysis

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Science China(Information sciences) 2012年第5期55卷 1106-1122页

作者： MA Yue 1,2.SUI YueFei 1 & CAO CunGen 1 1 Key Laboratory of Intelligent Information Processing,Institute of Computing Technology,chinese academy of {2.,Beijing 100190,China 2.graduate {4. of chinese academy of {2.,Beijing,China 1. Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Formal concept analysis (FCA) and description logic (DL) are meant to be formalizations of concepts.A formal concept in the former consists of its intent and extent,where the intent is the set of all the attributes shared by each object in the extent of the concept,and the extent is the set of all the objects sharing each property in the intent of the concept.A concept in the latter formalization is simply a concept name,the interpretation of which is a subset of a *** consider the correspondence between concepts in both formalizations,a multi-valued formal context must be represented both as a knowledge base and as a model of the DL for contexts,where concepts are decomposed into tuple concepts C,interpreted as a set of tuples and value concepts V,interpreted as a set of attribute-value *** show that there is a difference between the interpretation of concepts R.V /R.C and the Galois connection between the extent/intent of formal concepts in *** to the Galois connection,there should be concepts of the form + R.V and + R.C inter-preted in FCA,and hence the logical language L for DL is extended to be L + together with + as a constructor so that + R.V and + R.C are well-defined ***,according to the interpretation in DL there should be pseudo concepts in FCA so that the interpretation of concepts R.V /R.C is the extent/intent of pseudo *** correspondence between formal concepts and concepts in L +,and between pseudo concepts and concepts in L are presented in this paper.

关键词： description logic formal concept analysis concept attribute/role

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Experimental study of ore gabbro liquid immiscibility

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Science China Earth sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2. XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4.1. Guangzhou Institute of Geochemistry, chinese {2. of {2., Guangzhou 51064., China 2. Wuhan university, Wuhan 4.0072. China 3. Institute of Geology, China Seismological Bureau, Beijing 10002., China 4. Faculty of Earth {2., China university of Geo{2., Wuhan 4.0074. China 1. Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Wuhan university 430072 Wuhan China 3. Institute of Geology China Seismological Bureau 100029 Beijing China 4. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, China. Experiments were conducted under (confining) pressure ranging from 4.0 to 500 MPa and temperature of 900— 12.0℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

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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 {2., Kunming 650011 graduate School of chinese academy of {2., Beijing 10004. graduate School of chinese {2. of sciences 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

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Architecture and application of integrated spatial information service platform for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 706-711页

作者： ZHANG Jin1, XIAO Jie2.1. College of Mining, Taiyuan university of Technology, Taiyuan 03002.1} China 2. Institute of Geodesy and Geophysics, {2. {2. of sciences, Wuhan 4.0077, China Taiyuan Univ Technol Coll Min Taiyuan 030024 Peoples R China chinese Acad Sci Inst Geodesy & Geophys Wuhan 430077 Peoples R China

Using enterprise GIS platform, spatial databases and modern information technology, building geo-spatial information service platform of digital mine which has the features of the data exchange service, enterprise GIS services, directory services, logging services, is key technology and application infrastructure for digital mine. Based on the support of geospatial information service platform of digital mine, the professional GIS application service adapter can be developed and the application supports related to mining application system can be realized. Using high-resolution satellite remote sensing data, the mine functional partition map and geographic grids can be divided, and the geographic grid parts, status and events of important features of the surface object were investigated and defined. The system architecture and technical characteristics of integrated spatial information service platform were analyzed firstly, which guarantee service ability of digital mine. The methods and applications of functional partition map for integrated management service platform were discussed which are the services scheme of digital mine. The application results indicated that digital mine upgrades and enhances the capability and range of mine surveying and mapping, and is of great significance for guarantee of efficient, green and intensive exploitation of mine.

关键词： platform architecture web services application services digital mine

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Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3, WANG Yong2. DU Xiaolong1, MEI Zengxia1, KONG Xianghe3, JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2. 4.1. State Key Laboratory for Surface Physics, Institute of Physics, chinese {2. of {2., Beijing 100080, China 2. Laboratory of Electron Microscopy, Institute of Physics, chinese {2. of {2., Beijing 100080, China 3. College of Physics and Engineering, Qufu Normal university, Qufu 2.3165, China 4. Beijing university of Technology, Beijing 10002., China 1. State Key Laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. College of Physics and Engineering Qufu Normal University 273165 Qufu China 3. Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. Beijing university of Technology 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 30 rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

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Avoided crossings between non-radial modes in low mass RGB stars

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Research in Astronomy and Astrophysics 2012年第12期12卷 1655-1665页

作者： Jun-Jun Guo1,2.3,Yan Li1,2.and Xiang-Jun Lai1,2.1 National Astronomical Observatories/Yunnan Observatory,chinese academy of {2., Kunming 650011,China 2.Key Laboratory for the Structure and Evolution of Celestial Objects,chinese academy of {2.,Kunming 650011,China 3 graduate university of chinese academy of {2.,Beijing 10004.,China National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650011 China graduate university of {2. academy of {4. Beijing 100049 China

Non-radial p modes and g modes appear simultaneously in red giant stars. Their frequencies have different variation rates,causing their frequencies to become close during stellar evolution so that avoided crossings *** separation between regions where acoustic waves and gravity waves propagate for l=1,2.and 3 is different,which results in the coupling efficiency also being *** present the results of numerical computations of the models we *** find that the two kinds of modes for l=2.and 3 need to be closer in frequency in order for a complete exchange to occur,compared to the case for modes with l=*** scaled oscillation frequencies also present better regularity with evolution than modes with l=1. In order to study the effect of the avoided crossings in detail,we set the mode which has the smallest mode inertia to be the p *** plot the two kinds of modes for l =1,2.and 3 in frequency and periodéchelle diagrams and find modes of l=2.and 3 fit the two relations better;they are more equally spaced in frequency and period than modes with l=*** careful observation of the two kinds oféchelle diagrams for l=2.and 3,we still find that some p modes shift a little from being equally spaced in frequency and some g modes,which are close to those p modes in period,shift a little from being equally spaced in ***,we study the relation between the deviation from period being equally spaced and the mode inertia of g modes for different *** g modes of l=1 with a period closer to the p mode have less inertia and the deviation is bigger in the periodéchelle *** deviation is also obvious. However g modes of l=2.and 3 shift a little or have almost no deviation from being equally spaced in period,even though some of them may have strong coupling and close mode inertia like in the p ***,we suggest a possible method for measuring period spacing of g modes precisely using mixed g modes with l=2.and 3 that have fewer observed mixed g m

关键词： stars:oscillations-stars:red giants

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Photodissociation/photoionization processes of chlorobromomethane induced by femtosecond laser pulses with pump-probe scheme

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chinese Science Bulletin 2008年第5期53卷 681-686页

作者： ZHANG Feng1,2. WEI ZhengRong1,2. CAO ZhenZhou1,2. ZHANG ChangHua1,2.& ZHANG Bing1,2.1 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, chinese academy of {2., Wuhan 4.0071, China 2.graduate {4. of chinese academy of {2., Beijing 100039, China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China graduate university of {2. academy of {4. Beijing China

The photodissociation/photoionization processes of chlorobromomethane (CH_2.rCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The dominate photoproducts are observed at different delay time of the pump (4.0 nm) and probe (800 nm) pulses and the corresponding time-dependence of them is obtained. The results show that the decaying time of the molecule CH_2.rCl in the A-band is in the 100 fs. The decaying tendencies of the fragment ions (CH_2.l^+ and CH_2.r^+) and the parent ion (CH_2.rCl^+) are almost the same and the relative ratios of the yields of them keep constant during the delay time of 0 to 150 fs. These facts suggest that the fragment ions come from the fragmentation of the parent ions in excited electronic states. The probabilities to form CH_2.l^+ and CH_2.r^+ are obtained from the relative ratio of the ion intensity and are about 71.6% and 14.2., respectively.

关键词：毫微秒激光氯溴化甲烷激光探针光解作用光化电离作用

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Time of impact of fragment P2.of comet SL 9 on Jupiter

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chinese Science Bulletin 1997年第5期42卷 396-398页

作者： ZHOU Hongnan,QIAN Bochen, HUANG Keliang and LI Qibin1. Department of Astronomy, Nanjing university, Nanjing 2.0093, China 2. Shanghai Observatory, chinese {2. of sciences, Shanghai 2.0030, China 3. Physics Department, Nanjing Normal university, Nanjing 2.0097, China 4. Beijing Astronomical Observatory, chinese {2. of sciences, Beijing 100080, China Department of Astronomy Nanjing University Nanjing China Shanghai Observatory Chinese Academy of Sciences Shanghai China Physics Department Nanjing Normal University Nanjing China Beijing Astronomical Observatory Chinese Academy of Sciences Behijing China

FROM 1994.07-16 to 1994.07-2., 2. fragments of comet SL 9 impacted against Jupiter in succession. During the impact period the impact of fragments D, E, K, N, P2.and S was observed in China. We used a 1.56-m telescope with the CCD camera of Shanghai Observatory to monitor Jupiter and its Galilean Satellites, obtaining 1000 high-quality images at B, V, I wave bands. Our data on optical wave bands are rather complete and valuable in the world. Specially, we got some images of Jupiter, Io and Europa in the impact time of fragment P2.impacting against Jupiter. This will help us understand the precise time, position, depth and energy of the P2.s collision. In this note, we report the impact time of fragment P2.of comet SL 9 and Jupiter. Since the impact of comet SL 9 was expected to take place on the side of Jupiter

关键词： comet comet Shoemaker-Levy 9 impacting against Jupiter impact time.

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