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Variation of karst spring discharge in the recent five decades as an indicator of global climate change: A case study at Shanxi, northern China

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Science China Earth Sciences 2005年第11期48卷 2001-2010页

作者： GUO Qinghai1, WANG Yanxin1, MA Teng1 & LI Luxiu2.1. School of Environmental Studies, China university of geosciences,{2., China 2. Office of Water Resource Management of Shanxi Province, Taiyuan 030001, China 1. School of Environmental Studies China University of Geosciences 430074 Wuhan China 2. Office of Water Resource Management of Shanxi Province 030001 Taiyuan China

Karst in Shanxi Province is representative of that in northern China, and karst water systems discharge in the form of springs that are among the most important sources for local water supply. Since the 1950s, attenuation has been the major trend of discharge variation of most karst springs at Shanxi. Based on the case study of 7 karst springs including Niangziguan, Xin’an, Guozhuang, Shentou, Jinci, Lancun, and Hongshan springs, the discharge variation process of karst springs was divided into natural fluctuation phase and anthropogenic impact phase. Discharge attenuation of the 7 karst springs was controlled mainly by climate and human activities, with their contributions being respectively about 60% and 40%. According to the dif-ference of the effect of climate and human activities for each spring, attenuation modes of spring discharge fall into three types: natural process dominated attenuation type, exploitation induced process dominated attenuation type, and mixed attenuation type. The total restored discharge variation of 7 karst springs matched well with the global air temperature change in 1956―2.00, clearly indicating the trend of global warming and aridity in the last several decades, and the analysis of discharge variation processes of karst springs can be used as a new tool for global change studies.

关键词： karst, Shanxi, spring discharge, attenuation, climate, human activity, global change

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Anatexis in Himalayan crust:Evidence from geochemical and chronological investigations of Higher Himalayan Crystallines

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Science China Earth Sciences 2005年第9期48卷 1347-1356页

作者： YANG Xiaosong1, JIN Zhenmin2.& MA Jin1 1. State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 10002., China 2. Faculty of Earth Sciences, China university of geosciences,{2., China 1. State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration 100029 Beijing China 2. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

Migmatization in Higher Himalayan Crystallines (HHC) results from anatexis. The widely distributed migmatites in HHC are an important clue to investigate the relationship be- tween anatexis and the origins of Higher Himalayan leucogranites (HHL), and to understand the effect of anatexis on crustal evolution during the post-collision period. We studied in detail the chemical features of three basic constituent parts of the migmatites, i.e. leucosome, mesosome and melanosome, and determined the K-Ar ages of leucosomes. Our studies indicate that type-I leucosome is the product of crystallization of melt generated by partial melting of mesosome at source region, but type-II leucosome and HHL probably underwent crystallization differentiation of plagioclase during melt aggregation and migration. The age of 2..67 Ma of Type-I leucosome, which is a little older than the beginning of MCT movement, indicates that anatexis may have played an important role in the formation of MCT. That the ages of type-II leucosome (ranging from 14.82.to 18.37 Ma) are consistent with that of HHL provides new chronological evidence for the relationship between migmatization and HHL. We obtained a very young age of 6.2. Ma of Type-II leucosome that provides new time constraint on magma activity in the central segment of Higher Himalayas.

关键词： Higher Himalayan Crystallines, migmatite, anatexis, leucosome, K-Ar age.

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Hierarchical Classification of Chinese Documents Based on N grams

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wuhan university Journal of Natural Sciences 2001年第Z1期6卷 416-422页

作者： Zhou Shui geng 1, Guan Ji hong 2. He Yan xiang 2.1. State Key Laboratory of Software Engineering, wuhan university, wuhan 430072. China 2. School of Computer Science, wuhan university, wuhan 430072. China State Key Laboratory of Software Engineering Wuhan University Wuhan China School of Computer Science Wuhan University Wuhan China

We explore the techniques of utilizing N gram information to categorize Chinese text documents hierarchically so that the classifier can shake off the burden of large dictionaries and complex segmentation processing, and subsequently be domain and time independent. A hierarchical Chinese text classifier is implemented. Experimental results show that hierarchically classifying Chinese text documents based N grams can achieve satisfactory performance and outperforms the other traditional Chinese text classifiers.

关键词： Chinese text classification N grams feature selection hierarchical classification

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Evolutionary patterns of Productida (Brachiopoda) morphology during the Permian in South China

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Science China Earth Sciences 2008年第11期51卷 1589-1600页

作者： ZHANG Yang1 & HE WeiHong1,2.1 Faculty of Earth Sciences, China university of geosciences,{2., China 2.Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, China university of geosciences,{2., China 1. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China 2. Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan 430074 China

The evolutionary patterns of Productida (brachiopod) morphology throughout the Permian show that while the percentage proportion of Productida (brachiopod) with strongly concentric and radial ornamentation declined from the Cisuralian to the Guadalupian, and then increased towards the Changhsingian via Wuchiapingian, the percentage proportion of Productida (brachiopod) with fine concentric and radial ornamentation distinctly increased from the Cisuralian to the Guadalupian, slightly declined towards the Wuchiapingian, and then increased towards the Changhsingian. From the Cisuralian to the Changhsingian, the percentage proportion of brachiopods with spinose ornamentation shows a persistent declining trend. The shell size generally indicates a miniaturization trend at species level during the Wuchiapingian to Changhsingian (including the transitional bed). These evolutionary patterns of brachiopod ornamentation and size are possibly related to the anoxia, food shortage, sea-level fluctuation, and change of substrate in the Permian (including the Permian-Triassic transitional interval) in South China.

关键词： brachiopod ornamentation size Permian South China

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The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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Science China(Technological Sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3, WANG Guilan1 & ZHENG Qiguang2.1. School of Material Science and Technology, Huazhong university of Science and Technology, wuhan 430074, China 2. Institute of Laser Technology and Engineering, Huazhong university of Science and Technology, wuhan 430074, China 3. Mechanical Engineering College, Hubei university of Technology, wuhan 430068, China 1. School of Material Science and Technology Huazhong University of Science and Technology Wuhan 430074 China 3. Mechanical Engineering College Hubei University of Technology Wuhan 430068 China 2. Institute of Laser Technology and Engineering Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

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A Principal Theorem of Normal Discretization Schemes for Operator Equations of the First Kind

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wuhan university Journal of Natural Sciences 2001年第4期6卷 767-768页

作者： Du Nai lin 1, Wang Hannah 2.1.School of Mathematics and Statistics, wuhan university, wuhan 430072. China 2. School of Foreign Languages and Literature,wuhan university,wuhan 430072.China wuhan university School of Mathematics and Statistics Wuhan China (GRID:grid.49470.3e) (ISNI:***) wuhan university School of Foreign Languages and Literature Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The authors announce a newly-proved theorem of theirs. This theorem is of principal significance to numerical computation of operator equations of the first kind.

关键词： operator equation of the first kind normal discretization scheme pure pseudoinverse

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Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan university Journal of Natural Sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. Department of Chemical Engineering, wuhan university of Technology, wuhan 430070, Hubei, China 2. College of Chemistry and Molecular Sciences, wuhan university, wuhan 430072. Hubei, China wuhan university of Technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

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A Microenvironment, Rather than Chemical, Initiates the Cardiomyogenic Differentiation of Marrow Stromal Cells

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wuhan university Journal of Natural Sciences 2004年第4期9卷 513-521页

作者： LIU Wei-xin 1,2., SONG Jian 1 , WAN Yu 1, PAN Guo-dong 1 , LIU Yu 1 , CHENG Bang-chang 2.,CHEN Xi-chang 1 1. School of Medicine, wuhan university, wuhan 430071, Hubei, China 2. Renmin Hospital, wuhan university, wuhan 430060, Hubei, China wuhan university School of Medicine Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university Renmin Hospital Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university School of Medicine Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university Renmin Hospital Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

To investigate the potential of cardiomyogenic differentiation of rat bone marrow stromal cells (MSCs), they were exposed to 5-azacytidine tretments (single/repeat) at varying concentrations (3, 5, 10 μmol/L) and the fates of the cells were analyzed by immunocytochemistry, Western blot and the reporter gene of enhanced cyan fluorescent protein (ECFP) under the control of ventricular myosin light chain 2.(MLC2.) promoter. MSCs were also cocultured with cardiomyocytes for periods up to 16 days, the expression of cardiac myosin heavy chain (MHC) and troponin I (Tn I) proteins was analyzed. After the induction with 5-azacytidine, neither spontaneously beating cells nor myotubes were found; MHC and Tn I proteins were also undetectable and no ECFP-positive MSCs were detected. But when cocultured with cardiomyocytes, spontaneously contracting MSCs were observed and cardiac specific proteins could be detected. The results proved that the novel effects of 5-azacytidine on the cardiomyogenic differentiation of MSCs should be questioned and a direct intercellular communication with cardiomyocytes is necessary for MSCs to differentiate into cardiomyocytes. Key words cardiomyocyte - cell differentiation - stem cell CLC number Q 813.5 - R 542.2.2.Foundation item: Supported by the Natural Science Foundation of Hubei Province (2.02.B00150)Biography: LIU Wei-xin (1976-), male, Ph. D candidate, research direction: stem cell and cellular biology.

关键词： cardiomyocyte cell differentiation stem cell

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Research on the Low Detonation Velocity Explosives Containing Nitroesters

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含能材料 2002年第1期10卷 24-26页

作者： Andrzej WOJEWσDKA 1,Andrzej MARANDA 2.(1. Silesian Technical university of Gliwice,44-100 Gliwice, Poland 2. Military university of Technology,00-908 Warsaw, Poland) Silesian Technical university of Gliwice Gliwice 波兰Military university of Technology Warsaw

Some explosive mixtures detonating at low velocity were experimentally investigated. Detonation velocity and critical diameter were measured for mixtures,being different in composition and density. An attempt of physi... 详细信息

关键词：爆炸速度硝基盐硝基酯引爆采矿工业混合物低速度临界参数

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Mineralogy and crystal structure determination of Mg-fillowite

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Science China Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2.1. China university of geosciences, Beijing 100083, China 2. Institute of Geology, Chinese Academy of Sciences, Beijing 10002., China 1. China university of geosciences 100083 Beijing China 2. Institute of Geology Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, China. It is of the trigonal lattice, with space group R-3, unit cell a=1.5143(3) nm, c=4.3191(2. nm, V=8.5736 nm3, Z = 18. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

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