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Cluster-based composition rule for Laves phase-related BCC solid solution hydrogen storage alloys

Rare Metals 2006年第Z1期25卷 252-255页

作者： WANG Qing CHEN Feng WU Jiang QIANG Jianbing DONG Chuang ZHANG Yao XU Fen SUN Lixian State Key Laboratory of Materials Modification Dalian University of Technology Dalian 116024 China State Key Laboratory of Materials Modification Dalian University of Technology Dalian 116024 China State Key Laboratory of Materials Modification Dalian University of Technology Dalian 116024 China State Key Laboratory of Materials Modification Dalian University of Technology Dalian 116024 China State Key Laboratory of Materials Modification Dalian University of Technology Dalian 116024 China International Center of Materials Physics Metals Research Institute Chinese Academy of Sciences Shenyang 110015 China Materials & Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China Materials & Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China Materials & Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

A new cluster line approach for the composition rule of Laves phase-related BCC solid solution hydrogen-storage alloys was presented. The cluster line in a ternary phase diagram refers to a straight composition line linking a specific binary cluster to the third element. In the Laves phase-related BCC solid solution alloy system such as Ti-Cr-V, Ti-Cr tends to form binary Cr2Ti Laves phase while Ti-V and Cr-V to form solid solutions. This Laves phase is characterized by a close-packing icosahedral cluster Cr7Ti6. A cluster line Cr7Ti6-V is then constructed in this system. Alloy rods with a diameter of 3 mm of compositions along this line were prepared by copper-mould suction method. The alloy structure is found to vary with the V contents. Furthermore, the P-C-T measurements indicate that the cluster-line (Cr7Ti6)1-xVx alloys have large hydrogen storage capacities.

关键词： Ti-Cr-V alloys composition rule cluster hydrogen storage

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Lightning activity and precipitation structure of hailstorms

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science china Earth sciences 2007年第4期50卷 629-639页

作者： FENG GuiLi1,2, QIE XiuShu3,1, YUAN Tie1 & NIU ShuZhen4 1 Laboratory of Lightning and Thunderstorm, Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of sciences, Lanzhou 730000, china 2 Shandong Research Institute of Meteorology, Jinan 250031, china 3 Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 4 The Meteorological Observatory of Henan Province, Zhengzhou 450003, china Laboratory of Lightning and Thunderstorm Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China Shandong Research Institute of Meteorology Jinan 250031China Institute of Atmospheric PhySics Chinese Academy of SciencesBeijing 100029China Laboratory of Lightning and Thunderstorm Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China Laboratory of Lightning and Thunderstorm Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China The Meteorological Observatory of Henan Province Zhengzhou 450003China

By using the cloud-to-ground (CG) lightning location data from the lightning detection network of He- nan Province, surface Doppler radar data and standard orbit data of PR, TMI and LIS on TRMM satellite, the spatial and temporal characteristics of CG lightning flashes in 10 severe hailstorms are analyzed. The results show that the percentage of +CG lightning in these hailstorms is high with an average value of 45.5%. There is a distinct increase in CG flash rate during the rapid development stage of hailstorms. The hailstone falling corresponds to an active positive flash period, and the increase of +CG flash rate is generally accompanied with a decrease of –CG flash rate. The flash rate declines rapidly during the dissipating stage of hailstorms. The precipitation structure and lightning activity in two typical hail- storms are studied in detail. It is found that strong convective cells with reflectivity greater than 30dBZ mainly are situated in the front region of hailstorms, whereas the trailing stratiform region is in the rear part of the hailstorms. The maximum heights of echo top are higher than 14 km. Convective rain con- tributes much more rainfall to the total than stratiform rain, and the convective rain takes about 85% and 97% of the total in the two cases, respectively. Total lightning in the hailstorms is very active with the flash rate up to 183 fl/min and 55 fl/min, respectively. The results also indicate that most lightning flashes occurred in the echo region greater than 30 dBZ and its immediate periphery. The probability of lightning occurrence is 20 times higher in the convective region than in the stratiform region. The result suggests that the lightning information is helpful to the identification of convective rain region. The linear relationship between flash rate and ice water content is disclosed primarily.

关键词： total lightning activity positive CG lightning hailstorm convective rain ice water content

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一个应用于短波通信的差错控制协议——动态滑动窗口协议

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计算机科学 2003年第1期30卷 111-112,F004页

作者：金燕文立中国科学院软件研究所北京100080

Dynamic sliding window is a novel ARQ protocol for half-duplex short-wave *** algorithm ex-tracts the virtue of Stop-and Wait and Sliding Window protocols,uses acknowledgements and timeouts to implement reliability,and changes sliding window size according to channel *** paper puts forward the idea and the model of this protocol,The paper also analyzes the performance of this protocol,compared to the case using Wait-and-Stop protocol.

关键词：短波通信差错控制协议动态滑动窗口协议数据帧半双工通信 ARQ协议

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A cloud of laser cooled 40Ca+ in a linear ion trap

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science Bulletin 2010年第Z2期 3094-3097页

作者： ZHOU Fei 1,2,XU YouYang 1,2,XIE Yi 1,2,GUO Bin 1,2,SHU HuaLin 3,LI JiaoMei 1,HUANG XueRen 1 &FENG Mang 11 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics and mathematics,chinese academy of sciences,Wuhan 430071,china 2Graduate University of the chinese academy of sciences,beijing 100049,china 3 School of Physics and Telecommunication Engineering,South china Normal University,Guangzhou 510006,china

A cloud of 40Ca+is successfully trapped and cooled using the radiation of a red-detuned 397 nm laser beam and a resonant 866 nm laser beam in our prototype linear ion trap,which was designed and constructed for studying quantum information *** have characterized the size of the ion cloud,estimating the temperature to be in the order of milli-Kelvins.

关键词： ion trap laser cooling quantum information processing

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Dilute Liquid of Instanton and Its Topological Charge Dominate the QCD Vacuum

Dilute Liquid of Instanton and Its Topological Charge Domina...

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6th china-Japan Joint Nuclear Physics Symposium

作者： Z.Q.Wang~* X.F.Lu~(* + **) F.Wang~(?) ~*Department of Physics Sichuan University Chengdu 610064 china ~+Institute of Theoretical Physics chinese academy of sciences beijing 100080 china ~(**)CCAST ( World Laboratory) R O.Box 8730 beijing 100080 china ~(?)Department of Physics Nanjing University Nanjing 210093 china

＜正＞APE smearing and overlap-Dirac operator are combined to filter QCD vacuum configu- *** results obtained from overlap fermions and improved 5Li cooling are compared,both of them exhibit structures of dilute liquid of *** the overlap fermions,improved 5Li cooling and APE smearing are combined to calculate the topological charge and identify the struc- ture of QCD *** results suggest dilute liquid of instanton dominance of topological charge fluctuations in quenched lattice QCD.

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Pollen indication to source plants in the eastern desert of china

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science Bulletin 2005年第15期 98-107页

作者： LI Yuecong1,2, XU Qinghai2, ZHAO Yingkui3, YANG Xiaolan4, XIAO Jule1, CHEN Hui2,5 & Lü Xinmiao5 1. Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2. College of Resources and Environment, Hebei Normal University, Shijiazhuang 050016, china 3. Department of Environmental Management, University of Central Lancashire, Preston, UN 4. Hebei Geography Institute, Hebei academy of sciences, Shijiazhuang 050011, china 5. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china

In order to investigate the indication of major pollen types to source plants, 39 surface pollen samples are collected from 39 plant communities. The results show that diversity of pollen assemblages presents in different commu-nities. Chenopodiaceae pollen percentages are highest in Kalidium communities and Ceratoides communities (higher than 45%, average is 63.4%), but high Ephedra pollen per-centages (higher than 3.3%, average is 16.5%)in Ceratoides communities make it distinguished from Kalidium communi-ties. Artemisia pollen percentages (more than 50%) are much higher than Chenopodiaceae (less than 35%) in Artemisia Communities. Nitraria pollen percentages (higher than 2%, average is 13.6%) are highest in Nitraria communities com-pared with those in other community patterns. Tamariceae pollen percentages (higher than 2%, average is 8.6%) are highest both in Tetraena and Reaumuria communities com-pared with those in other community patterns. But in Reau-muria communities, Artemisia pollen percentages are higher than Chenopodiaceae with some other pollen types such as Gramineae, Compositae, Leguminosae; on the contrary, in Tetraena communities, Artemisia pollen percentages are less than Chenopodiaceae with few other pollen types. Calli-gonum pollen only appears in Calligonum communities (higher than 2%,average is 5%). The results of cluster analysis (CLA) and detrended correspondence analysis (DCA) show that the pollen indication to source plants can be reflected by association indices (A), over-representation in-dices (O), under-representation indices (U), R-value, the av-erage pollen percentages where parent plants are absent (Xa) and the average pollen percentages where parent plants are present (Xp). Zygophyllum, Calligonum, Tetraena, Tribulus and Tamariceae can indicate source plants very well, owing to high A scores. Artemisia, Chenopodiaceae and Gramineae have high R-values, and Nitraria, Cruciferae and sedum have high O scores, so they are over-represente

关键词： eastern desert of china pollen indication association indices (A) over-representation indices (O) under-representation indices (U) correlation coefficients (CC) similarity coefficients (C) detrended correspondence analysis (DCA) cluster analysis (CLA) ratios of Nitraria and Ephedra (N/E) ratios of Ephedra and Artemisia (E/A) ratios of Artemisia and Chenopodiaceae (A/C).

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Simulation analysis on the regulation of overflow ecological water consumption in arid areas——A case study in the Canmrik ecological area of the mainstream zone of the Tarim River

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science china Earth sciences 2007年第S1期 1-8页

作者： CHEN Xi1, HUANG Yue1, 2, QIAN Jing1, 3, LIU HaiLong1, 2, FENG XianWei1, 2, LIU Ying1, 2, BAO AnMing1 & WANG WeiSheng1 1 Xinjiang Institute of Ecology and Geography, chinese academy of sciences, ürümqi 830011, china 2 Graduate University of chinese academy of sciences, beijing 100049, china 3 Hong Kong Baptist University, Hong Kong, china

After analyzing the regulation of overflow ecological water consumption in the Canmrik ecological area of mainstream zone of the Tarim River, in this paper a model of ecological bifurcation is developed, the dynamic overflow process of ecological bifurcation is simulated, and the quantitative relationships between the volume of ecological water consumption and the ecological conservation extent and overflow time are analyzed using GIS, advance of freshet and RS means. The results reveal that the effects of discharge and time of ecological bifurcation on the efficiency of ecological water consump-tion are significant, there is a geometrical exponential relationship between the efficiency of ecological bifurcation and the water supply with different discharges and different times under the same eco-logical water consumption, hypsography plays an important role in ecological water consumption, the regulation of ecological water consumption cannot be equated with the ordinary farming irrigation system, a serious water waste will result and the prospective ecological benefits will not be able to be achieved if an ordinary ecological bifurcation is implemented. The efficiency of ecological water con-sumption can be increased by 30% by selecting the bifurcation schemes in an optimized way, which is of the utmost importance for arid areas with shortage of water resources.

关键词： continental river ecological water consumption artificial regulation simulation analysis

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Editor’s note

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chinese science Bulletin 2009年第16期54卷 2723-2723页

作者： YAO TanDong & TIAN LiDe Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085, china State Key Laboratory of Cryosphere sciences, Cold and Arid Regions Environment and Engineering Research Institute, chinese academy of sciences, Lanzhou 730000, china Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China State Key Laboratory of Cryosphere sciences Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

In 1961, the Global Network Isotopes in Precipitation (GNIP) was operated by the IAEA in collaboration with WMO, and over 500 stations across the globe participated in this program. The initial objective of this progr... 详细信息

关键词：环境同位素世界气象组织水文地球化学国际原子能机构大气环流模式气温变化水资源管理全球网络

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线性约束0-1二次规划的一个定界技术

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系统科学与数学 1999年第1期19卷 65-71页

作者：朱文兴张连生上海大学数学系

本文给出确定线性约束0－1二次规划问题最优值下界的方法，该方法结合McBride和Yormark的思想和总体优化中定下界的方法，证明了所定的界较McBride和Yormark的要好．求解线性约束0－1二次规划问题的分支定界算法可以利用本文的定界技术．

关键词：二次规划定界凸二次规划 0-1二次规划最优值

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Privilege Flow Oriented Intrusion Detection Based on Hidden Semi-Markov Model

Privilege Flow Oriented Intrusion Detection Based on Hidden ...

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The 1st chinese Conference on Trusted Computing and Information Security

作者： ZHONG An-ming, JIA Chun-fu College of Information Technology and sciences. Nankai University. Tianjin 300071 .china State Key Laboratory of Information Security, Institute of Software of chinese academy of science, beijing 100039,china

＜正＞ A privilege flow oriented intrusion detection method based on HSMM （ Hidden semi-Markov Model） is discussed. The privilege flow model and HSMM are incorporated in the implementation of an anomaly detection IDS （Intrusion Detection System）. Using the data set of DARPA 1998, our experiment results reveal good detection performance and acceptable computation cost.

关键词： intrusion detection privilege flow model HSMM

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