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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 200092, China 2 college of natural and computational sciences, {3., {3., hi 96744, USA 3.State Key Laboratory of Geological Processes and Mineral Resources, Faculty of Earth sciences, China university of Geosciences, Wuhan 43.074, 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

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, college of Science, Nanjing {3. of Science and Technology, Nanjing 210094, 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

New research progress on the ultrastructure of tectonically deformed coals

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Progress in natural Science:Materials International 2009年第11期19卷 1455-1466页

作者： Yiwen Ju,Xiaoshi Li Laboratory of computational Geodynamics,college of Earth Science,Graduate {3. of Chinese Academy of {3.,Beijing 100049,China [a]Laboratory of computational Geodynamics College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China

The structure of tectonically deformed coals shows some characteristics and regulations on the ultra-scale when influenced by different factors such as temperature,pressure and directional *** of the macromolecular structure may induce changes in the nano-scale pore structure,which are very important for gas adsorption and *** geological impact of different mechanisms of deformation on different types of ultrastructure of tectonically deformed coals is not only of significance as a topic for scientific research, but also in studying environments of metamorphism-deformation at differing metamorphic *** research is also very important in studying the accumulation and occurrence conditions of coalbed methane gas,mechanisms of coal and gas outbursts,predictions of coalbed methane resources and dangers of coal and gas *** paper analyzes current research,within China and other countries, in the ultrastructure of tectonically deformed *** research includes(1) structural models of tectonically deformed coals;(2) the relationship between ultrastructure and stress;(3. the structure of tectonically deformed coals and its strain *** results are also based on our own experiments including vitirnite reflectance(Ro,max),X-ray diffraction(XRD) and nuclear magnetic resonance (NMR(CP/MAS + TOSS)).We discuss the important effects of the structure of tectonically deformed coals and their physical properties,and then point out some problems concerning the research progress of tectonically deformed coals.

关键词： Tectonically deformed coals Ultrastructure Pore structure Tectonic stress Strain environment

^(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 {3. of Mining and Technology, Xuzhou 221008, China 2. Laboratory of {3. 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 13. 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.

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 73.000, C{3.na 2. LASG, Institute of Atmospheric Physics, C{3.nese Academy of sciences, Beijing 100029, C{3.na) 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—2005. 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

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 100022, C{3.na 2. Center for Nonlinear Studies, Institute of Applied Physics and {3. Mathematics, Beijing 100088, C{3.na) 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

The gravitational gradient tensor’s invariants and the related boundary conditions

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Science China Earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2,3.& ZHAO DongMing4 1 college of Earth Science, Graduate university of Chinese Academy of {3., Beijing 100049, China 2 Institute of Geodesy and Geophysics, Chinese Academy of {3., Wuhan 43.077, China 3.State Key Laboratory of Astronautic Dynamics, Xi’an 710043. China 4 Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052, China 1. college of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China3. State Key Laboratory of Astronautic Dynamics Xi’an 710043 China4. Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2-term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2/2 T), which is approximately equivalent to O(T2). Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 200, and the models with regard to effect of J2-term have accuracies of 10-8 and the order can reach up to 280.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

CENOZOIC VOLCANISM AND GEOTHERMAL RESOURCES IN NORTHEAST ChiNA

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Chinese Geographical Science 2001年第2期11卷 150-154页

作者： WANG Xi-kui1, QIU Shan-wen2, SONG Chang-chun2, KULAKOV Aleksey3. TASHChi Stepan3. MYASNIKOV Evgeny3.(1.college of Earth sciences, Jilin {3.,Changchun 13.012,P.R.China 2.Changchun Institute of Geography, the Chinese Academy of sciences,Changchun college of Earth sciences Jilin University Changchun P. R. China Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China pacific Institute of Geography Far East Science Center of the Russian Academy of Sciences Vladivostok Russia

This paper is concentrated on Cenozoic volcanism and geothermal resources in Northeast China. There are a lot of Cenozoic volcanoes, a large area of volcanic rocks, a large number of active faults and rich geothermal resources in Northeast China. The time and space characteristics of Cenozoic volcanism and the space distribution characters of hot springs and high geothermal flux regions in Northeast China are described and discussed on the basis of geological, geothermal, drilling and volcanological data. It is revealed that the hot springs and high geothermal flux regions are related to the Cenozoic volcanism, rifting and faulting in Northeast China. It is especially emphasized that the hot springs and high geothermal anomaly areas are controlled by active deep faults. It is proposed that the Cenozoic volcanism regions, rift basins, active fault belts, activated plate suture zones and large earthquake occurrence points are the best areas for prospecting geothermal resources. The geothermal resources in younger volcanic zones are richer than those in older volcanic belts. The hot springs and active or activated faults might be a very good clue for looking for geothermal resources.

关键词： volcanism active faults geothermal resources Northeast China

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.