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Normality and shared values concerning differential polynomials

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Science china Mathematics 2010年第3期53卷 749-754页

作者： LEI ChunLin 1 & FANG MingLiang 2. 1 Department of Applied Mathematics, South china Agricultural University, guangzhou 51064., china 2.institute of Applied Mathematics, South china Agricultural University, guangzhou 51064., china 1. Department of Applied Mathematics South China Agricultural University Guangzhou 510642 China2. Institute of Applied Mathematics South China Agricultural University Guangzhou 510642 China

Let F be a family of functions meromorphic in a domain D, let P be a polynomial with either deg P≥3 or deg P = 2.and P having only one distinct zero, and let b be a finite nonzero complex number. If, each pair of fun... 详细信息

关键词： meromorphic function normality shared value

Determination of paleo-pressure for a natural gas pool formation based on PVT characteristics of fluid inclusions in reservoir rocks——A case study of Upper-Paleozoic deep basin gas trap of the Ordos Basin

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Science china Earth Sciences 2004年第6期47卷 507-513页

作者： MI Jingkui1,2.XIAO Xianming1,LIU Dehan1,& SHEN Jiagui1 1.State Key Laboratory of Organic geochemistry,guangzhou {2. of geochemistry,Chinese Academy of Sciences,guangzhou 51064.,china 2.{2. of Sedimentary Mineral and Resources,Department of Civil Engineering,Xiangtan Polytechnic University,Xiangtan 4112.1,china 1. State Key Laboratory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangz China 2. institute of Sedimentary Mineral and Resources Department of Civil Engineering Xiangtan Polytechnic University 411 Xiangtan China

It has been proved to be a difficult problem to determine directly trapping pressure of fluid inclusions. Recently, PVT simulation softwares have been applied to simulating the trapping pressure of petroleum inclusions in reservoir rocks, but the reported methods have many limita- tions in practice. In this paper, a method is suggested to calculating the trapping pressure and temperature of fluid inclusions by combining the isochore equations of a gas-bearing aqueous inclusion with its coeval petroleum inclusions. A case study was conducted by this method for fluid inclusions occurring in the Upper-Paleozoic Shanxi Formation reservoir sandstones from the Ordos Basin. The results show that the trapping pressure of these inclusions ranges from 2. to 32.MPa, which is 6─7 MPa higher than their minimum trapping pressure although the trapping temperature is only 2.3℃ higher than the homogenization temperature. The trapping pressure and temperature of the fluid inclusions decrease from southern area to northern area of the basin. The trapping pressure is obviously lower than the state water pressures when the inclusions formed. These data are consistent with the regional geological and geochemical conditions of the basin when the deep basin gas trap formed.

关键词： Ordos Basin, fluid inclusion,PVTsim,trapping pressure.

RAZUMIKHIN-TYPE THEOREMS FOR ASYMPTOTIC STABILITY OF IMPULSIVE STOCHASTIC FUNCTIONAL DIFFERENTIAL SYSTEMS

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 72-84页

作者： Pei CHENG~1 Feiqi DENG~2.Xisheng DAI~3 Systems Engineering institute,South china University of Technology,{2. 51064.,china Systems Engineering institute South China University of Technology Guangzhou China

In this paper, we investigate the pth moment uniformly asymptotic stability of impulsive stochastic ftmctional differential systems by extending some Razumikhin-type theorems. Based on the Lyapunov functions and Razumikhin techniques, some criteria are established and their applications to impulsive stochastic delay systems are proposed. An illustrative example shows the effectiveness of our results.

关键词： Stochastic functional differential systems Impulse Razumiltial theorems Asymptotic stability

Trace element geochemistry of the Lower Cambrian black rock series from northwestern Hunan, South china

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Progress in Natural Science:Materials International 2004年第1期14卷 65-71页

作者： PAN Jiayong 1,2. *, MA Dongsheng 1 and CAO Shuanglin 1,2. (1.The State Key Laboratory for Mineral Deposits Research, Nanjing University, Nanjing 2.0093, china 2. East china {2. of Technology, Fuzhou 344000, china) Nanjing Univ State Key Lab Mineral Deposit Res Nanjing 210093 Peoples R China E china Inst Technol Fuzhou 344000 Peoples R China

Samples of black rock series collected from the Lower Cambrian Niutitang Formation, northwestern Hunan Province, china, were analyzed for trace elements. The trace element geochemical characteristics of the ore layer (high enrichments of Ni, Mo, V, U, Cu, Pb, Zn, Cd, Tl and Ba; high U/Th ratios and LREE enriched patterns with positive Eu and Y anomalies) support the assumption that the Ni Mo polymetallic layer is of submarine hydrothermal origin. High field strength elements (HFSE) and lithophile elements such as Nb, Ta, Zr, Hf, Li, Be, Rb, Cs, Th and Sc are remarkably higher in the upper unit than those in the lower unit of the Niutitang Formation. These features may reflect that hydrothermal contributions were diminished, and terrigenous constituents were increased in the sediments of the upper unit of the Niutitang Formation.

关键词： black rock series Early Cambrian trace elements northwestern Hunan china

Water pricing towards sustainability of water resources: a case study in Beijing

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Journal of Environmental Sciences 2002年第4期14卷 518-523页

作者： LIU Shao (guangzhou Research institute of Environmental Protection, guangzhou 51062., china. ) guangzhou Heseureh institute of Environmental Protection Guangzhou 510620

The role of water pricing for managing water resources is widely recognized in many areas of the world because of the increasing scarcity of water resources, a high competition between water uses and environmental degradation. Based on the analysis of cost of water, this paper explores which types of cost should be reflected in the water pricing enhancing the sustainability of water resources. The principle of full cost pricing in which the cost should include supply cost, opportunity cost and externalities is proposed as a means to achieve the sustainability of water resources. In a case study of Beijing, low water price is analyzed as one reason for unsustainable water consumption. Thus water pricing justified is necessary and pressing. It is proposed to justify water price in phased manner and eventually towards full cost pricing. The assessment of impacts on water resources by raising water price shows water pricing could alleviate the conflict between water supply and demand. This paper concludes that water pricing can play an effective role in enhancing the sustainability of water resources in Beijing.

关键词： water resources water price cost full cost pricing sustainability Beijing

The fluxes and controlling factors of N_2. and CH_4 emissions from freshwater marsh in Northeast china

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Science china Earth Sciences 2010年第5期53卷 700-709页

作者： YU JunBao1,2. LIU JingShuang2. SUN ZhiGao1, SUN WeiDong3, WANG JinDa2. WANG GuoPing2.& CHEN XiaoBing1 1 Key Lab of Coastal Envionment Processed, Yantai institute of Coastal Zone Research for Sustainable Development, Chinese Academy of Sciences, Yantai 2.4003, china 2.Key Lab of Wetland Ecology and Environment, Northeast institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012. china 3 Key Laboratory of Isotope Geochronology and geochemistry, guangzhou institute of geochemistry, Chinese Academy of Sciences, guangzhou 51064., china 1. Key Lab of Coastal Envionment Processed Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China2. Key Lab of Wetland Ecology and Environment Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 China3. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Nitrous oxide (N2.) and methane (CH4) emissions were measured using a static chamber method in two adjacent plots of freshwater marsh predominated by Calamagrostis angustifolia, one is seasonal waterlogged (SW) and the other without surface water accumulation (NW), in Sanjiang Plain wetland (47°35′N, 133°31′E), northeast china, during 2.02.2.04. The diurnal and seasonal flux variations of both gases were significantly correlated with 5-cm-soil temperature. The NW marsh is a source of N2. and sink of CH4, while the SW marsh is sink of N2. and source of CH4. Remarkably, we observed a N2. emission peak under Eh of +300 to +100 mV, and CH4 emission peak under Eh of +300 to +400 mV, which indicate additional sources of N2. and CH4 for the freeze-thaw induced emission peaks of N2. and CH4 observed between late July and early August. Further study shows that the additional N2. and CH4 were emitted under the frozen soil after thawing.

关键词： freeze-thaw region freshwater marsh methane nitrous oxide controlling factors

2./3D-QSAR comparative study on mutagenicity of nitroaromatics

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Science china Chemistry 2005年第3期48卷 246-252页

作者： WANG Xiaodong1, LIN Zhifen2. YIN Daqiang1, LIU Shushen1 & WANG Liansheng1 1. State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment at Nanjing University, Nanjing 2.0093, china 2. Key Laboratory of Tropical Marine Environmental Dynamics, South china Sea {2. of Oceanology, Chinese Academy of Sciences, guangzhou 510301,china 1. State Key Laboratory of Pollution Control and Resources Reuse School of the Environment at Nanjing University 210093 Nanjing China 2. Key Laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences 510301 Guangzhou China

Nitroaromatics are typical toxic organic pollutants and are ubiquitous in environment with diverse structures. They are widely used in many industries and formed during many natural and anthropogenic processes. Most of these pollutants are potentially carcinogenic and the as-sessment and prediction of the mutagenicity of nitroaromatics are of great interest. In this paper the structure-mutagenicity relationships of 2.9 nitroaromatics are investigated by molecular or-bital theory based classic structure-activity relationships and comparative molecular field analysis (CoMFA). A comparison is undertaken in respect of the interpretation of mechanism and predic-tive ability for these two categories of QSAR approaches and highly predictive QSAR models have been developed.

关键词： nitroaromatics, mutagenicity, mechanism, 3D-QSAR, CoMFA.

Relationship between magnetic fabric parameters and dynamic characteristics of deposits in different environments

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Chinese Science Bulletin 1998年第22期43卷 1917-1921页

作者： CHEN Qingqiang 1,3 , LI Congxian\+1 and CONG Youzi\+2.1. Marine Geology Laboratory, Tongji University, Shanghai 2.0092. china 2. First institute of Oceanography, State Oceanic Administration of china, Qingdao 2.6003, china 3. guangzhou institute of Marine Geology Laboratory Tongji University Shanghai China guangzhou institute of {2. Chinese Academy of Sciences Guangzhou China First institute of Oceanography State Oceanic Administration of China Qingdao China

Comparison of magnetic fabric parameters of deposits in different modern sedimentary environments indicates that values of \%P, F\% and \%L\% of eolian deposits are lower obviously than those of hydrogenic ones respectively. On relationship diagrams of magnetic fabric parameters, data points of eolian samples concentrated in limited area near origin of coordinates indicate that dynamic intensity is lower with less variation; while those of hydrogenic ones depart from origin of coordinates suggest higher intensity of sedimentary dynamics. Analyses of dynamic characteristics of different sedimentary environments indicate that values of magnetic fabric parameters of deposits are determined by dynamic types and characteristics of depositional processes. Magnetic fabric analyses of deposits are effective in determination of sedimentary environments.

关键词： magnetic fabric parameters sedimentary environment transporting medium.

Quasirational dynamic system

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Chinese Science Bulletin 2000年第14期45卷 1277-1279页

作者： SUN Daochun & YANG Lo1. Department of Mathematics, South china Normal University, guangzhou 510631, china 2. institute of Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, china Department of Mathematics South China Normal University Guangzhou China institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China

Using the iterations of quasirational mappings, the theorems on dynamic system are generalized to the quasirational dynamic system. Some different results are also obtained.

关键词： quasirational mapping dynamic system covering surface.