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Structure of augmentation quotients of finite homocyclic abelian groups

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Science China Mathematics 2007年第9期50卷 1280-1288页

作者： Guo-ping TANG School of Mathematical sciences,graduate {2. of {3. Academy of sciences,beijing 100049,China 1. School of Mathematical sciences Graduate University of Chinese Academy of Sciences Beijing 100049 China

Let G be a finite abelian group and its Sylow p-subgroup a direct product of copies of a cyclic group of order p r , i.e., a finite homocyclic abelian group. Let Δ n (G) denote the n-th power of the augmentation ideal Δ(G) of the integral group ring ?G. The paper gives an explicit structure of the consecutive quotient group Q n (G) = Δ n (G)/Δ n+1(G) for any natural number n and as a consequence settles a problem of Karpilovsky for this particular class of finite abelian groups.

关键词： integral group ring augmentation ideal consecutive quotient of augmentation ideal 16S3. 2.C05

Input function and simulated distributions of tritium in the North Pacific

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Science China Earth sciences 2010年第3期53卷 441-453页

作者： BA Qi1,2.& XU YongFu1 1 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, chinese Academy of sciences, {2. 10002., China 2.{3. university of chinese Academy of sciences, beijing 100049, China 1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

An ocean general circulation model (OGCM) of the North Pacific with a southern open boundary condition is used to simulate the distribution and transport of tritium in the North Pacific. First, the observed tritium in precipitation dataset of GNIP/ISOHIS is chosen, and used to develop an input function of tritium for the model domain from 1951 to 1997 in terms of the triangulation for interpolation. Then, the input function is used as an upper flux for the tritium model. The OGCM with tritium is integrated for 47 years with the initial condition of zero tritium concentrations. Compared with the observations from GEOSECS and WOCE, the model generates a meridional gradient of surface tritium concentrations and the high tritium concentrations in the subsurface layer, which is consistent with that indicated in the observations. The simulated time series of total tritium fluxes from the atmosphere to the ocean shows a spike in 1963. The total inventory of tritium in the ocean changes slowly with time after 1975. Tritium enters the higher-latitude region, and then is mainly transported by the subsurface process towards the equatorial region, which is well simulated in the model. However, the difference mainly occurs at 3.°N–40°N, which can be seen also in the simulation of CFCs. This difference may partly originate from the insufficient description of physical processes in the OGCM. Nevertheless, some uncertainties exist in the development of the tritium input function, which can also influence the simulated results.

关键词： North Pacific basin-wide ocean general circulation model tritium input function tritium distributions

Discovery of submicron diamonds within kimberlite in Liaoning Province, China and its significance

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chinese Science Bulletin 1997年第11期42卷 939-941页

作者： BAO Yanan, T. V. Dubuchick and T. D. Liabchekov1. graduate School in beijing, {2. Mining {3., beijing 100083. China 2. Moscow Resources Institute of Mineral Materials, Russia 3. Resources Institute of Deposit Geology, Russian Academy of sciences, Russia graduate School in beijing Chinese Mining University Beijing China Moscow Resources Institute of Mineral Materials Russia Resources Institute of Deposit Geology Russian Academy of Sciences Russia

ALTHOUGH a lot of research work on diamond mineralogy has already been done,the formationand development of diamond leave much to be *** have done some researches onthe diamond samples with obvious crystal-growing cha... 详细信息

关键词： submicron diamond lath-shape aggregative parent material.

Triaxial ellipsoid models of the Moon based on the laser altimetry data of Chang'E-1

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Science China Earth sciences 2010年第11期53卷 1594-1601页

作者： WANG WenRui1,2.3. LI Fei1, LIU JianJun1, REN Xin2. ZOU XiaoDuan2.3. MU LingLi2. YAN JianGuo1, ZOU YongLiao2. ZHANG HongBo2. Lü Chang2. LIU JianZhong2. ZUO Wei2. SU Yan2. WEN WeiBin2. BIAN Wei2. WANG Min2. LI ChunLai2.& OUYANG ZiYuan2.1 School of Geodesy and Geomatics, Wuhan university, Wuhan 43.079, China 2.National Astronomical Observatory of chinese Academy of {2., {3. 100012. China 3.graduate School of chinese Academy of {2., beijing 100049, China 1. School of Geodesy and Geomatics Wuhan University Wuhan 430079 China2. National Astronomical Observatory of Chinese Academy of Sciences Beijing 100012 China3. Graduate School of Chinese Academy of Sciences Beijing 100049 China

Lunar geodetic parameters, which play an important role in lunar exploration, can be calculated from the gravity and topography data. With the CE-1 altimetry data and LP gravity model, we calculate such geodetic parameters as the principle moment of inertia, the principle inertia axes, equatorial radius, polar radius, mean radius, flattening and offset between center of mass and center of figure (DCOM-COF). According to the CE-1 altimetry data and the above geodetic parameters, a tri-axial ellipsoid (CE-1-LAM-GEO) and a tri-axial level ellipsoid (CE-1-LAM-LEVEL) are calculated individually, providing mass center and figure center offset (DCOM-COF) and parameters more reliable in direction and magnitude.

关键词： Chang’E-1 laser altimetry data lunar ellipsoid lunar gravity

Quasi-secure quantum dialogue using single photons

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2.& WEN QiaoYan3. College of Computer Science and Technology, beijing university of Technology, beijing 10002., China 2.State Key Laboratory of Information Security, {3. university of the chinese Academy of sciences, beijing 100049, China 3.School of Science, beijing university of Posts and Telecommunications, beijing 100876, China College of Computer Science Technology Beijing University of Technology Beijing 100022 China State Key Laboratory of Information Security Graduate University of the Chinese Academy of Sciences Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

Effects of isolation after sexual experience on anxiety-like, depressive-like behaviors and affective states in male rats

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chinese Science Bulletin 2010年第36期55卷 4136-4142页

作者： WEN Fei1,2.& XU Lin1,3.1 Laboratory of Learning and Memory and Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, the chinese Academy of sciences, Kunming 6502.3. China 2.{2. {3. of the chinese Academy of sciences, beijing 100049, China 3.Mental Health Institute, the 2.d Hospital of Central South {3., Changsha 410011, China Laboratory of Learning and Memory and Key Laboratory of Animal Models and Human Disease Mechanisms Kunming Institute of Zoology the Chinese Academy of Sciences Kunming 650223 China graduate university of the {2. Academy of {3. Beijing 100049 China Mental Health Institute the 2nd Hospital of Central South University Changsha 410011 China

Studies on social isolation have provided evidence for an enhanced anxiety-like phenotype, depressive-like symptoms and higher levels of 2.-kHz ultrasonic vocalizations (USVs); whereas sexual experience could induce significant changes in affective states, decrease anxiety-and depressive-like responses. However, the behavioral and emotional alterations in male rats exposed to isolation after sexual experience remain poorly understood. Therefore, the present study examined anxiety-and depressive-like parameters, as well as USV emissions in male rats isolated for 1, 2. or 7 d following 1-week sexual (male-female paired housing) or social (male-male paired housing) interaction. Isolation for 1 d resulted in increased depressive-like symptoms, and 2.d isolation induced elevated anxiety-like behavior in sexually inexperienced rats, while rats with sexual experience exhibited comparable levels of emotionality at each isolation time. Moreover, isolated rats without sexual experience emitted less 2.-and 50-kHz USVs, but sexually experienced rats exhibited similar affective states compared with control ones. These results suggested that prior sexual experience could have a modulatory effect on experimental rat emotional responses to isolation.

关键词：雄性大鼠情感状态焦虑抑郁行为情绪变化相互作用调节作用

Nitrogen isotopic composition of plant-soil in the Loess Plateau and its responding to environmental change

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chinese Science Bulletin 2009年第2期54卷 272-279页

作者： LIU WeiGuo1,2.& WANG Zheng1,3.1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, chinese Academy of sciences, Xi’an 710075, China 2.Xi’an Jiaotong {2., School of Human Settlement and Civil Engineering, Xi’an 710049, China 3.{3. {2. of chinese Academy of sciences, beijing 100049, China chinese Acad Sci Inst Earth Environm State Key Lab Loess and Quaternary Geol Xian 710075 Peoples R China.

The nitrogen isotope of soil is of emerging significance as an indicator of climatic change and biogeochemical cycle of nitrogen in nature systems. In this paper, the nitrogen content and isotopic composition of modern ecosystems from arid and semiarid Loess Plateau in northwestern China, including plant roots and surface soil, were determined to investigate trends in δ15N variation of plant roots and soil along a precipitation and temperature gradient in northwestern China under the East Asian Monsoon climate condition. The δ15N values of surface soil from the study area vary from ?1.2. to 5.8‰, but from -5.1‰ to 1.9‰ in the plant roots. Our results indicate that (1) although the isotopic compositions of both plant roots and surface soil change with a similar trend along the climate gradient, the apparent nitrogen difference between plant roots and soil existed, with -δ15N values ranging from 0.3. to 7.2. with average of 4.1‰; and (2. mean annual precipitation (MAP) is the dominant factor for isotopic composition of plant-soil nitrogen in the Loess Plateau, and the δ15N values are less correlated with MAT; we suggest that nitrogen isotopic composition of soil is a potential tracer for environmental changes.

关键词：氮同位素物理性质化学性质环境论

The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2.3.and Xin-Wu Cao1,2.1 Shanghai Astronomical Observatory, chinese Academy of {3., Shanghai 2.003., China 2.Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, Shanghai 2.003., China 3.{2. School of the chinese Academy of {3., beijing 100049, China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate School of the chinese Academy of {2. Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2.cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 2.8 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

Monitoring of rice crop using ENVISAT ASAR data

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Science China Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2. SUN Guoqing1,3.& PANG Yong4 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, chinese Academy of sciences, {2. 100101, China 2. {3. university of chinese Academy of sciences, {2. 10003., China 3. Department of Geography, university of Maryland, College Park, MD 2.742. USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, chinese Academy of For-estry, {2. 100091, China 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. graduate university of {2. Academy of {3. Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.