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Exploring the deep biosphere

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Science China Earth sciences 2011年第2期54卷 157-165页

作者： FANG JiaSong1,2.& ZHANG Li3 1 State Key Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. China 2.college of natural and computational sciences, hawaii {2. University, kaneohe, hi 96744, usa 3 State Key Laboratory of Geological Processes and Mineral Resources, Faculty of Earth sciences, China University of Geosciences, Wuhan 430074, China 1. State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China2. College of Natural and Computational Sciences Hawaii Pacific University Kaneohe HI 96744 USA3. State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Over the past two decades, scientific drilling into sediments and rocks in the ocean and the continent has revealed the presence of physiologically and phylogenetically complex microbial life in the deep subsurface. Microorganisms, most of which have no cultured or known relatives in the surface biosphere, have been discovered in sediments and rock at depth as deep as 1 km below the seafloor and more than 3 km deep in the continent. The deep biosphere probably represents the most voluminous part of the global biosphere and may constitute as much as 50% of the Earth’s biomass. In this article, we review the current knowledge of and most recent advances in studying the deep biosphere and suggest directions in future research.

关键词： deep biosphere Thomas Gold microorganism biomass DNA ribosome ODP CARD-FISH dark energy lipids serpentinization

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, Chinese 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 1948—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

^(13)C NMR spectra of tectonic coals and the effects of stress on structural components

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Science China Earth sciences 2005年第9期48卷 1418-1437页

作者： JU Yiwen1,2. JIANG Bo1, HOU Quanlin2. WANG Guiliang1 & NI Shanqin2.1. college of Mineral Resource and Geosciences, China University of Mining and Technology, Xuzhou 2.1008, China 2. Laboratory of {2. Geodynamics, college of Geosciences, Graduate School of Chinese Academy of sciences, Beijing 100049, China 1. college of Mineral Resource and Geosciences China University of Mining and Technology 221008 Xuzhou China 2. Laboratory of computational Geodynamics College of Geosciences Graduate School of Chinese Academy of Sciences 100049 Beijing China

high-resolution 13C Nuclear Magnetic Resonance (NMR) spectra of different kinds of tectonic coals were obtained using the NMR (CP/MAS+TOSS) method. On the basis of this, after simulation synthesis and division of spectra, the relative contents of carbon functional groups were calculated. Combined with results of Ro, max, XRD testing and element analysis, stress effects on the composition of macromolecular structures in tectonic coals were studied further. The results showed that Ro, max was not only the important index for describing coal rank, but was also effective for estimating the stress effect of tectonic coals. Under tectonic stress ac- tion, Ro, max was the most direct indicator of the coal structure and chemical components. Changes in the stacking Lc of the coal basic structure unit (BSU) and La/Lc parameters could distinguish the temperature and stress effects on metamorphic-deformed environments, and re- flected the degree of structural deformation. Therefore, on the whole, Lc and La/Lc can be used to index of the degree of structural deformation of tectonic coals. In different metamorphic and de- formed environments, different kinds of tectonic coals are formed under structural stress. The changes in characteristics of the macromolecular structure and chemical composition are such that as the increase in structural deformation becomes stronger, from the brittle deformation coal to ductile deformation coal, the ratio of width at the half height of the aromatic carbon and ali- phatic carbon peaks (Hfa/Hfal ) was increased. As carbon aromaticity was raised further, carbon aliphaticity reduced obviously and different compositions of macromolecular structure appeared as a jump and wave pattern except for in wrinkle structure coal, which might result chiefly from stress effects on the macromolecular structure of different kinds of tectonic coals. The macro- moecular changes of wrinkle structure coal are reflected mainly on physical structure. In the metamorphi

关键词： tectonic coal, NMR, macromolecular structure, chemical component, stress effect.

Existence of solutions for the dynamic equation of ferrimagnets

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Progress in natural Science:Materials International 2007年第11期17卷 1279-1283页

作者： Zeng Ming1, Guo Boling2.and Cheng Caozong1(1. college of Applied sciences, Beijing University of Technology, Beijing 10002., China 2. Center for Nonlinear Studies, Institute of Applied Physics and {2. Mathematics, Beijing 100088, China) college of Applied sciences Beijing University of Technology Beijing 100022 China Center for Nonlinear Studies Institute of Applied Physics and Computational Mathematics Beijing 100088 China

Ferrimagnet is a kind of basic and important multi-sublattice magnet material. It has attracted more and more attention of physicists and mathematicians. Many results of solitons and numerical computations on this topic have appeared. In this article, the dynamic equation for an isotropic ferrimagnet with two non-equivalent sublattices is studied, existence of weak solutions in multi dimension case is proved through the penalized method, the uniqueness and smoothness of the solution in one dimension case are also obtained by the relation between this equation and hyperbolic equation.

关键词： ferrimagnet weak solutions penalized method finite difference method

Nonlinear local Lyapunov exponent and atmospheric predictability research

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Science China Earth sciences 2006年第10期49卷 1111-1120页

作者： CHEN Baohua1, LI Jianping1,2.& DING Ruiqiang2.1. college of Atmospheric sciences, Lanzhou University, Lanzhou 730000, China 2. State Key Laboratory of Numerical Modeling for Atmospheric Science and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 10002., China 1. college of Atmospheric sciences Lanzhou University Lanzhou 730000 China 2. State Key Laboratory of Numerical Modeling for Atmospheric Science and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Because atmosphere itself is a nonlinear system and there exist some problems using the linearized equations to study the initial error growth, in this paper we try to use the error nonlinear growth theory to discuss its evolution, based on which we first put forward a new concept: nonlinear local Lyapunov exponent. It is quite different from the classic Lyapunov exponent because it may characterize the finite time error local average growth and its value depends on the initial condition, initial error, variables, evolution time, temporal and spatial scales. Based on its definition and the at-mospheric features, we provide a reasonable algorithm to the exponent for the experimental data, obtain the atmospheric initial error growth in finite time and gain the maximal prediction time. Lastly, taking 500 hPa height field as example, we discuss the application of the nonlinear local Lyapunov exponent in the study of atmospheric predictability and get some reliable results: atmospheric predictability has a distinct spatial structure. Overall, predictability shows a zonal distribution. Prediction time achieves the maximum over tropics, the second near the regions of Antarctic, it is also longer next to the Arctic and in subtropics and the mid-latitude the predictability is lowest. Particularly speaking, the average prediction time near the equation is 12.days and the maximum is located in the tropical Indian, Indonesia and the neighborhood, tropical eastern pacific Ocean, on these regions the prediction time is about two weeks. Antarctic has a higher predictability than the neighboring latitudes and the prediction time is about 9 days. This feature is more obvious on Southern Hemispheric summer. In Arctic, the predictability is also higher than the one over mid-high latitudes but it is not pronounced as in Antarctic. Mid-high latitude of both Hemispheres (30°S―60°S, 30°―60°N) have the lowest predictability and the mean prediction time is just 3―4 d. In addition, predictab

关键词： nonlinear, local, Lyapunov exponent, atmospheric predictability, maximal prediction time.

A general finite element model for numerical simulation of structure dynamics

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 440-450页

作者： WANG Fujun1, LI Yaojun1, Han K.2.& Feng Y.T.2.1. college of Water Conservancy and Civil Engineering, China Agricultural University, Beijing 100083, China 2. Civil & computational Engineering Centre, University of Wales Swansea, Swansea SA2.8PP, U.K. college of Water Conservancy Civil Engineering China Agricultural University Beijing 100083 China Civil & computational Engineering Centre University of Wales Swansea Swansea SA2 8PP UK

A finite element model used to simulate the dynamics with continuum and discontinuum is presented. This new approach is conducted by constructing the general contact model. The conventional discrete element is treated as a standard finite element with one node in this new method. The one-node element has the same features as other finite elements, such as element stress and strain. Thus, a general finite element model that is consistent with the existed finite element model is set up. This new model is simple in mathematical concept and is straightforward to be combined into the existing standard finite element code. Numerical example demonstrates that this new approach is more effective to perform the dynamic process analysis in which the interactions among a large number of discrete bodies and continuum objects are included.

关键词： finite element method, discrete element method, structure dynamics, numerical simulation.

The Signless Laplacian Spectral Radius of Tricyclic Graphs with k Pendant Vertices

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Journal of Mathematical Research with Applications 2012年第3期32卷 281-287页

作者： Jingming ZHANG1,2.Jiming GUO 2.1.School of Mathematical sciences,University of Electronic Science and Technology of China, Sichuan 611731,P.R.China 2.college of Mathematics and {2. Science,China University of Petroleum, Shandong 2.7061,P.R.China School of Mathematical sciences University of Electronic Science and Technology of China Sichuan 611731 college of Mathematics and computational Science China University of Petroleum Shandong 257061

In this paper,we determine the unique graph with the largest signless Laplacian spectral radius among all the tricyclic graphs with n vertices and k pendant vertices.

关键词： signless Laplacian spectral radius tricyclic graph pendant vertex.

A new smoothing scheme for mathematical programs with complementarity constraints

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Science China Mathematics 2010年第7期53卷 1881-1890页

作者： YAN TaoDepartment of Information and computational sciences, {2. of Science, Nanjing University of Science and Technology, Nanjing 2.0094, China 1. Department of Information and computational sciences College of Science Nanjing University of Science and Technology Nanjing 210094 China

In this paper, we consider a mathematical program with complementarity constraints (MPCC). We present a new smoothing scheme for this problem, which makes the primal structure of the complementarity part unchanged mostly. For the new smoothing problem, we show that the linear independence constraint qualification (LICQ) holds under some conditions. We also analyze the convergence behavior of the smoothing problem, and get some sufficient conditions such that an accumulation point of stationary points of the smoothing problems is C (M, B)-stationarity respectively. Based on the smoothing problem, we establish an algorithm to solve the primal MPCC problem. Some numerical experiments are given in the paper.

关键词： mathematical program with complementarity constrains MPEC-LICQ B-stationarity C-stationarity M-stationarity

A self-calibration algorithm for cross array in the presence of mutual coupling

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Science China(Information sciences) 2011年第4期54卷 836-848页

作者： HU XiaoQin 1,2.CHEN Hui 2.WANG YongLiang 2.& CHEN JianWen 2.1 college of Electronic Science and Engineering,National University of Defense Technology,Changsha 410073,China 2.Key Lab of Wuhan Radar Academy,Wuhan 430019,China 1. college of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China2. Key Lab of Wuhan Radar Academy Wuhan 430019 China

In this paper,a novel blind mutual coupling self-calibration algorithm especially tailored to cross array is *** method compensates for the mutual coupling not only between sensors in each subarray but also between two *** the property of coupling matrix,the proposed method requires neither the calibration sources in known locations nor the multidimensional nonlinear *** method can jointly estimate the DOAs of the incoming signals and the unknown mutual coupling coefficients,and has high estimation precision and low computational *** analysis and computer simulations show the effectiveness of the proposed algorithm.

关键词： cross array mutual coupling self-calibration DOA estimation