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Calculation of light emission in sonoluminescence

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Science china(Physics,Mechanics & Astronomy) 2009年第4期52卷 593-601页

作者： li ChaoHui1 & AN Yu1,2 1 Department of Physics,Tsinghua University,beijing 100084,china 2 Institute of Acoustics,chinese academy of sciences,beijing 100190,china Department of Physics Tsinghua University Beijing China Institute of Acoustics Chinese Academy of Sciences Beijing China

We modify a uniform model of single bubble sonoluminescence,in which heat diffusion,water vapor diffusion and chemical reactions are included to describe the bubble dynamics,and the processes of electron-atom bremsstrahlung,electron-ion bremsstrahlung and recombination radiation,radiative attachment of electrons to atoms and molecules,line emissions of OH radicals and Na atoms are taken into account to calculate the light emission. With this model,we compute the light pulse width,the photon number per flash,the continuum and line spectra and the gas species as the products of chemical reactions,and try to compare with all the experimental data available. We obtain good agreement with the observations of Ar and Xe bubbles in many cases,but fail to match the experimental data of the photon number per flash. We also find that for He bubble the computed photon number is always too small to interpret the observations.

关键词： sonoluminescence bremsstrahlung radiative attachment line spectrum collision broadening

Lattice Boltzmann solver of Rossler equation

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Communications in Nonlinear Science and Numerical Simulation 2000年第2期5卷 64-68页

作者： Guangwu YAN and li RUAN (LSEC Institute of Computational Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china Department of Mathematics, Jilin University, Changchun 130023, china) LSEC Institute of Computational Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China Department of Mathematics Jilin University Changchun 130023 China

We proposed a lattice Boltzmann model for the Rossler equation. Using a method of multiscales in the lattice Boltzmann model, we get the ditheion reaction as a special case. If the diffusion effect disappeared, we can obtain the lattice Boltzmann solution of the Rossler equation on the mesescopic scale. The numericale results show the method can be used to simulate Rossler equation.

关键词： lattice Boltzmann method multiscale technique Rossler equation

Systematic distortion in cosmic microwave background maps

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 804-808页

作者： liU Hao 1,3 &li TiPei 1,2 1Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,chinese academy of sciences,beijing 100049,china 2Center for Astrophysics,Tsinghua University,beijing 100084,china 3 Graduate University of chinese academy of sciences,beijing 100049,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China Center for Astrophysics Tsinghua University Beijing China

To minimize instrumentally the induced systematic errors,cosmic microwave background(CMB)anisotropy experiments measure temperature differences across the sky using pairs of horn antennas, temperature map is recovered from temperature difference obtained in sky survey through a map-making *** inspect and calibrate residual systematic errors in the recovered temperature maps is important as most previous studies of cosmology are based on these *** analyzing pixel-ring coupling and latitude dependence of CMB temperatures,we find notable systematic devia- tion from CMB Gaussianity in released Wilkinson Microwave Anisotropy Probe(WMAP)*** detected deviation cannot be explained by the best-fit LCDM cosmological model at a confidence level above 99%and cannot be ignored for a precision cosmology study.

关键词： cosmology cosmic microwave background methods data analysis

Functional evolutionary developmental biology (evo-devo) of morphological novelties in plants

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Journal of Systematics and Evolution 2010年第2期48卷 94-101页

作者： Jisi ZHANG Ying TIAN li WANG Chaoying HE (State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

The origin of morphological and ecological novelties is a long-standing problem in evolutionary *** these processes requires investigation from both the development and evolution standpoints,which promotes a new research field called "evolutionary developmental biology" (evo-devo).The fundamental mechanism for the origin of a novel structure may involve heterotopy,heterochrony,ectopic expression,or loss of an existing regulatory ***,the morphological and ecological traits controlled by the regulatory genes may be gained,lost,or regained during *** morphological novelties,for example,include homeotic alterations (related to organ identity),symmetric diversity,and changes in the size and morphology of the floral *** gains and losses can potentially arise through modification of the existing regulatory ***,we review current knowledge concerning the origin of novel floral structures,such as "evolutionary homeotic mutated flowers",floral symmetry in various plant species,and inflated calyx syndrome (ICS) within *** evo-devo of the morphological novelties is a central theme of plant evolutionary *** addition,the discussion is extended to consider agronomic or domestication-related traits,including the type,size,and morphology of fruits (berries),within Solanaceae.

关键词： biodiversity development evolution functional evo-devo heterochrony heterotopy morphological novelty

Preliminary results of a regional air-sea coupled model over East Asia

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chinese Science Bulletin 2010年第21期55卷 2295-2305页

作者： li Tao ZHOU GuangQing Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the chinese academy of sciences Beijing 100049 China

We have established a regional air-sea coupled model over East Asia and conducted a 20-year integration to evaluate its performance in reproducing the present *** coupled model consists of RegCM3 and HYCOM controlled by the OASIS3 coupler with resuolution of 60 km for the atmosphere and 33 km for the ocean,*** some other regional air-sea coupled models,a one-way nesting method is employed in the oceanic component and a heat flux adjustment for solar radiation is used to remove an about 2°C cold bias in *** primary analysis for this 20-year integration shows that the coupled model successfully reproduces the main features of the circulations over East Asia,both in the atmosphere and the ocean,including climatology,seasonal and interannual *** are seen in the coupled model compared to the uncoupled one,especially in the simulation of precipitation,the most important element of the East Asian monsoon,although there are still obvious discrepancies that come mainly from the model components *** analyses show that the rainfall simulation benefits from the enhancements of the Northwest Pacific Subtropical High in summer,which leads to the improvement of the moisture flux simula-tion at the middle-lower atmospheric *** results indicate that the regional air-sea coupled model is more suitable for the East Asia monsoon simulation.

关键词：海气耦合模式东亚地区空气西北太平洋副高大气环流海域耦合模型模拟降雨

Dynamic tree-based authenticated group key exchange protocol

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Science china(Information sciences) 2010年第8期53卷 1591-1602页

作者： li Hui 1,2 , WU ChuanKun 1 & TENG JiKai 1,2 1 State Key Laboratory of Information Security, Institute of Software, chinese academy of sciences, beijing 100190, china 2 Graduate University of chinese academy of sciences, beijing 100049, china State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Authenticated group key exchange protocols allow a group of users over a public network to establish a shared secret key for the subsequent cryptographic goals. In this paper, we extend BD-II scheme into a dynamic setting, and propose a tree-based authenticated key exchange protocol which is more suitable for dynamic groups in such as ad hoc networks. Our protocol is proven secure in random-oracle model. Additionally, we analyze the costs of our protocols in both communication and computation terms, and compare its performance with three well-known protocols.

关键词： tree-based group key exchange dynamic provable security

Compression Properties of Ti-Al-X Alloys in Relation to Site Occupancies of Alloying Elements in TiAl and Ti_3Al

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Journal of Materials Science & Technology 1999年第6期15卷 536-540页

作者： Yulin HA O Rui YANG, Yuyou CUI and Dong li(Institute of Metal Research, chinese academy of sciences, 72 Wenhua road, Shenyang 110015, china)Wanfu GAO(Fushun Petroleum Institute, Dandong road, Fushun 113001, china) Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110015 China Fushun Petroleum Institute 1 Dandong Road Fushun 113001 China

Room temperature compression properties of Ti-51Al-(1~2)X and Ti-26Al-(1~2)X alloys (X=***, Mn, Fe, Co. Ni, Zr, Nb, Mo, Ta, Ga or Sn) were measured in order to examine how the compression deformability correlates with the site occupancies of the alloying elements in γ-TiAl and α2-Ti3Al. The results showed that, for the γ phase, the compression ratio is not related to the site preference of the alloying elements in a simple way. For the α2 phase, the following correlation was observed between the compression ratio and the site occupancies of the investigated elements, those which occupy Al sites decrease the deformability, while those occupying Ti sites (except V) improve the deformability of the α2 phase. Compression properties of dual-phase TiAl alloys based on Ti-46Al-(1, 3, 5)X were also measured at room temperature to test aHypothetica l mechanism of ductilization based on mechanical compatibility at phase *** was concluded that no simple relationship exists between the deformability of the dual-phase alloys and the properties of their constituent phases.

关键词： TiAl Ni Site Cr

Report of Prionospio complex(Annelida:Polychaeta:Spio-nidae) from china's waters,with description of a new species

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Acta Oceanologica Sinica 2009年第1期28卷 116-127页

作者： ZHOU Jin li Xinzheng Institute of Oceanology. Chinese Aeademy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Nine species of Prionospio complex are recorded from china＇s waters,including one new species and six newly recorded ***（Prionospio） pacifica ***.,is characterized by having first and forth pairs of branchiae pinnate,second and third pairs of apinnate,ventral crest on Setiger 9 and dorsal crests on Setigers *** kirrae（Wilson,1990）,Prionospio（Aquilaspio） convexa Imajima,1990,Prionospio（Minuspio） multibranchiata Berkeley,1927,Prionospio（Prionospio） bocki Sderstrm,1920,Prionospio（Prionospio） dubia Maciolek,1985 and Prionospio（Prionospio） paradisea Imajima,1990 are recorded for the first time from china＇s waters.

关键词： taxonomy Prionospio complex new species newly recorded species china's waters.

Characteristics of the Middle-Late Triassic sedimentary facies assemblages in the Songpan-Ruoergai area

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Progress in Natural Science:Materials International 2007年第3期17卷 305-313页

作者： YAN Zhen, YU liangjun, li Jiliang, BIAN Qiantao, WANG Zongqi and YANG Yongcheng ( Institute of Geology, chinese academy of Geological sciences, beijing 100037, china State Key Laboratory of lithospheric Evolution, Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china Shaanxi Insititute of Geology Survey, Xianyang 712000, china) Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Shaanxi Insititute of Geology Survey Xianyang 712000 China

The Middle-Late Triassic sedimentary rocks in the Songpan-Ruoergai area mainly consist of calcareous siltstone, muddy limestone, lithic arkose, feldspathic litharenite, mudstone, wormkalk, oolithic limestone, and conglomerate. Except for limestone bed increasing eastward longitudinally and vertically, the calcareous component of the sandstones increases obviously. Abundant benthic and plant fossils and their clasts occur within these rocks. The sedimentary structures predominately contain flaser, parallel, tabular, wavy, and herringbone cross beddings. These data coevally imply that the Middle-Late Triassic sediments deposited in the fluvial, lake and tide environments. Additionally, the rocks display graded, parallel, hummocky beddings, and sandy lamination, a feature characteristic of storm deposits.

关键词： Middle-Upper Triassic fluvial-lake environments tide environment tempestite Songpan-Ruoergai