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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3 & YE Xianren2.1. Resources and Environmental School, Lanzhou university, Lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of {2., Lanzhou 730000, china 3. college of Resources Science & technology, beijing Normal university, beijing 100875, china 1. Resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. college of Resources Science & technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3He from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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Theoretical analysis of polarization properties for tilted fiber Bragg gratings

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Science china(Information sciences) 2010年第2期53卷 390-397页

作者： xu Ou 1 , LU ShaoHua 2.& JIAN ShuiSheng 2.1 Faculty of Information Engineering, Guangdong {2. of technology, Guangzhou 510006, {2. 2.Institute of Lightwave technology, beijing Jiaotong {2., beijing 100044, {2. 1. Faculty of Information Engineering Guangdong University of Technology Guangzhou 510006 China2. Institute of Lightwave Technology Beijing Jiaotong University Beijing 100044 China

The polarization properties for tilted fiber Bragg gratings (TFBGs) are investigated theoretically based on coupled-mode theory and Mueller matrix method. The expression of wavelength-related polarizationdependent loss (PDL) for TFBGs with different tilt angles is derived and calculated. Simulation results are compared, and the results indicate that the polarization capability of TFBGs with 45° angle is stronger than other TFBGs with smaller angles. The degree of polarization for unpolarized light passing TFBGs is also simulated to further evaluate the polarization properties for various tilt angles. In addition, the relationship between physical parameters of a TFBG and its polarization capability is discussed.

关键词： coupled-mode theory degree of polarization (DOP) Mueller matrix method polarization dependent loss (PDL) tilted fiber Bragg gratings

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Analysis of moment invariants under general linear transformation

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Science china(Information sciences) 2010年第7期53卷 1305-1311页

作者： DIAO LuHong1, LI Hua2. ZhanG Sen1 & LIU Lei1 1college of {2. {2., beijing university of technology, beijing 10012., china 2.ational Center of Intelligent Computing, Institute of Computing technology, Chinese Academy of Science, beijing 100080, china 1. college of applied {2. Beijing University of Technology Beijing 100124 China2. National Center of Intelligent Computing Institute of Computing Technology Chinese Academy of Science Beijing 100080 China

This paper presents the necessary and sufficient condition of moment invariants under general linear transformation. Based on this condition, arbitrary order and dimensional moment invariant sets can be constructed. D... 详细信息

关键词： moment invariants independence linear transformation

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Complex variable method for plane elasticity of icosahedral quasicrystals and elliptic notch problem

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 773-780页

作者： LI LianHe1,2.& FAN TianYou1 1 Department of Physics, beijing Institute of {2., beijing 100081, china 2.college of Mathematics Science, Inner Mongolia Normal university, Hohhot 01002., china Department of Physics Beijing Institute of Technology Beijing 100081 China college of Mathematics Science Inner Mongolia Normal University Hohhot 010022 China

The complex variable method for the plane elasticity theory of icosahedral quasicrystals is developed. Based on the general solution obtained previously, complex representations of stress and displacement components of phonon and phason fields in the quasicrystals are given. With the help of conformal transformation, an analytic solution for the elliptic notch problem of the material is presented. The solution of the Griffith crack problem can be observed as a special case of the results. The stress intensity factor and energy release rate of the crack are also obtained.

关键词： icosahedral quasicrystals plane elasticity elliptic notch complex variable method

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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2. WU Li-xin1, 2. LI Hui-ying3.1. college of Resources and Civil Engineering, Northeastern {2., Shenyang 110004, china 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, beijing Normal {2., beijing 100875, china 3. college of Computer Science and technology, Jilin {2., Changchun 130012. china [a] college of Resources and Civil Engineering Northeastern University Shenyang 110004 China [b] Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China [c] college of Computer Science and technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

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Effects of salinity on methane gas hydrate system

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Science china Earth sciences 2007年第11期50卷 1733-1745页

作者： YANG DingHui1 & xu WenYue2.1 Department of Mathematical sciences, Tsinghua {2., {2. 100084, china 2.School of Earth & Atmospheric sciences, Georgia Institute of technology, Atlanta, GA 30332. USA 1. Department of Mathematical sciences Tsinghua University Beijing 100084 China 2. School of Earth & Atmospheric sciences Georgia Institute of Technology Atlanta GA 30332 USA

Using an approximately analytical formation, we extend the steady state model of the pure methane hydrate system to include the salinity based on the dynamic model of the methane hydrate system. The top and bottom boundaries of the methane hydrate stability zone (MHSZ) and the actual methane hy-drate zone (MHZ), and the top of free gas occurrence are determined by using numerical methods and the new steady state model developed in this paper. Numerical results show that the MHZ thickness becomes thinner with increasing the salinity, and the stability is lowered and the base of the MHSZ is shifted toward the seafloor in the presence of salts. As a result, the thickness of actual hydrate occur-rence becomes thinner compared with that of the pure water case. On the other hand, since lower solubility reduces the amount of gas needed to form methane hydrate, the existence of salts in sea-water can actually promote methane gas hydrate formation in the hydrate stability zone. Numerical modeling also demonstrates that for the salt-water case the presence of methane within the field of methane hydrate stability is not sufficient to ensure the occurrence of gas hydrate, which can only form when the methane concentration dissolved in solution with salts exceeds the local methane solubility in salt water and if the methane flux exceeds a critical value corresponding to the rate of diffusive methane transport. In order to maintain gas hydrate or to form methane gas hydrate in marine sedi-ments, a persistent supplied methane probably from biogenic or thermogenic processes, is required to overcome losses due to diffusion and advection.

关键词： methane gas hydrate,solubility,stability of hydrate,salinity,phase equilibrium

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Study on the drug resistance and the binding mode of HIV-1 integrase with LCA inhibitor

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Science china Chemistry 2007年第5期50卷 665-674页

作者： HU JianPing1,2. ChanG Shan1, CHEN WeiZu1 & WANG CunXin1 1 {2. of Life Science and Bioengineering, beijing university of technology, {2. 10002., china 2.Department of Chemistry & Life sciences, Leshan Normal university, Leshan 614004, china college of Life Science and Bioengineering Beijing University ofTechnologyBeijing 100022China Department of Chemistry & Life sciences Leshan NormalUniversityLeshan 614004China

Human immunodeficiency virus type 1 (HIV-1) integrase (IN) is an essential enzyme in the lifecycle of this virus and also an important target for the study of anti-HIV drugs. The binding mode of the wild type IN core domain and its G140S mutant with L-Chicoric acid (LCA) inhibitor were investigated by using multiple conformation molecular docking and molecular dynamics (MD) simulation. Based on the binding modes, the drug resistance mechanism was explored for the G140S mutant of IN with LCA. The results indicate that the binding site of the G140S mutant of IN core domain with LCA is different from that of the core domain of the wild type IN, which leads to the partial loss of inhibition potency of LCA. The flexibility of the IN functional loop region and the interactions between Mg2. ion and the three key residues (i.e., D64, D116, E152. stimulate the biological operation of IN. The drug resistance also lies in several other important effects, such as the repulsion between LCA and E152.in the G140S mutant core domain, the weakening of K159 binding with LCA and Y143 pointing to the pocket of the G140S mutant. All of the above simulation results agree well with experimental data, which provide us with some helpful information for designing the drug of anti-HIV based on the structure of IN.

关键词： molecular docking, MD simulation, HIV-1 IN, drug design

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Threshold quantum secure direct communication without entanglement

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3 & WEN QiaoYan2.1 college of Computer Science and technology, {2., beijing 10002., china 2.School of Science, beijing university of Posts and Telecommunications, beijing 100876, china 3 State Key Laboratory of Information Security (Graduate School of Chinese Academy of sciences), beijing 100049, china 1. college of Computer Science and technology Beijing University of Technology Beijing 100022 China 3. State Key Laboratory of Information Security (Graduate School of Chinese Academy of sciences) Beijing 100049 China 2. School of Science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

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Bursting of Morris-Lecar neuronal model with current-feedback control

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Science china(Technological sciences) 2009年第3期52卷 771-781页

作者： duAN LiXia1, LU QiShao2.& CHENG DaiZ{2.3.1.college of Science, North {2. university of technology, beijing 100144, {2. 2.School of Science, beijing university of Aeronautics and Astronautics, beijing 100191, {2. 3 Institute of Systems Science, Chinese Academy of sciences, beijing 100190, {2. college of Science North China University of Technology Beijing 100144 China School of Science Beijing University of Aeronautics and Astronautics Beijing 100191 China Institute of Systems Science Chinese Academy of Sciences Beijing 100190 China

The Morris-Lecar (ML) neuronal model with current-feedback control is considered as a typical fast-slow dynamical system to study the combined influences of the reversal potential VCa of Ca2. and the feedback current I on the generation and transition of different bursting oscillations. Two-parameter bifurcation analysis of the fast subsystem is performed in the parameter (I, VCa)-plane at first. Three important codimension-2.bifurcation points and some codimension-1 bifurcation curves are obtained which enable one to determine the parameter regions for different types of bursting. Next, we further divide the control parameter (V0, VCa)-plane into five different bursting regions, namely, the "fold/fold" bursting region R1, the "fold/Hopf" bursting region R2. the "fold/homoclinic" bursting region R3, the "subHopf/homoclinic" bursting region R4 and the "subHopf/subHopf" bursting region R5, as well as a silence region R6. Codimension-1 and -2.bifurcations are responsible for explanation of transition mechanisms between different types of bursting. The results are instructive for further understanding the dynamical behavior and mechanisms of complex firing activities and information processing in biological nervous systems.

关键词： neuron bursting bifurcation fast-slow dynamics analysis codimension

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Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural Science:Materials International 2007年第10期17卷 1127-1135页

作者： Song Nanmeng1, Sang Jianli1 and xu Heng2.1. Institute of Cell Biology, college of Life Science, {2. Normal {2., {2. 100875, china 2. Emory {2. School of Medicine, GA 30332. USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875， China Emory university School of Medicine GA 30332 USA

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.

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