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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,{3., china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences,{3., china 3. college of resources Science & Technology, beijing normal university,{14., china resources and environmental School Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China college of resources Science & Technology Beijing Normal University Beijing 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 ~3.e/~4.e in almost all samples range from 0.82 Ra to 2.74.Ra, whereas^(4.)Ar/^(3.)Ar from 299.5 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/~3.e range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3.e from 2.5 x 10~9 to 27 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.

Research progress in studies on the coalbed gas geochemistry

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Progress in Natural Science:Materials International 2006年第3期16卷 215-220页

作者： TAO Mingxin (college of resources Sciences & Technology, beijing {3. {4., beijing 100875, china Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences, lanzhou 730000, china) college of resources Sciences & Technology Beijing Normal University Beijing 100875 China Key Laboratory of Gas Geo- chemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China

The current situation of geochemical studies on coalbed gas is reviewed in this paper. Generally, coalbed gas is composi-tionally dominated by methane with δ13.1 values ranging approximately from - 80‰ to - 10‰. However, few isotopic studies have been carried out on other components of coalbed gas except for hydrogen and carbon dioxide, whose δDCH4.values available for utilization vary from - 3.3. to - 117‰, and δ13.CO2 values from - 29. 4. to + 18. 6‰. Two major types of coalbed gas, thermogenic gas and secondary biogenic gas, have been identified, and there are also some other classification criteria. Compared with conventional natural gases, coalbed gas has a wide distribution range of δ13.1 and δ13.CO2 values, especially possessing some extremely heavy values. Current problems that remain unsolved in the coalbed gas geochemistry include the variation mechanism, controlling factors and application of carbon and hydrogen isotopes of methane, the relation between the values of δ13.1 and Ro, the systematic classification scheme and criterion of genetic types, and the application of the coalbed gas geochemistry in evaluating target districts of the coalbed gas exploration.

关键词： coalbed gas geochemistry isotopic composition genetic type novel resource.

Evidence from carbon isotope measurements for biological origins of individual long-chain n-alkanes in sediments from the Nansha Sea,china

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Chinese Science Bulletin 2002年第7期47卷 578-581页

作者： DUAN Yi & WANG ZhipingState Key Laboratory of Gas Geochemistry, lanzhou Institute of Geology, Chinese Academy of Sciences, lanzhou 730000, china Institute of {3.al Science, {4. normal university, beijing 100875, china State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China Institute of environmental Science Beijing Normal University Beijing China

Carbon isotopes are measured for individual long-chain n-alkanes in sediments from the Nansha Sea. The features of carbon isotopic compositions of individual n-alkanes and their origins are studied. The results show that the long-chain n-alkanes have a light carbon isotopic composition and a genetic feature of mixing sources, and low-latitude higher plants and microbes are considered to be their main end member sources. Based on the abundances and carbon isotopic compositions of individual n-alkanes, the fractional contributions of the two end member sources to individual n-alkanes are quantitatively calculated by using a mixing model. The obtained data indicate that the fractional contributions of the two biological sources are different in the three samples. A trend is that the contribution of microbes increases with the depth. These results provide the theory basis and quantitatively studied method for carbon isotopic applied research of individual n-alkanes.

关键词： modern marine sediment individual n-alkane carbon isotopic composition biological source.

Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2,3. Feng Zhaodong4.and Gong Huili1,2(1. MOE and Key Laboratory of resources environment and GIS of beijing, beijing 10003., china 2. Key Laboratory of 3. information Acquisition and Application, The Capital normal university, beijing 10003., china 3. Department of Economics & Management of Huizhou university, Huizhou 516007, china 4. Key Laboratory of Western china’s environmental Systems, Ministry of Education,{13., lanzhou 730000, china) MOE and Key Laboratory of resources environment and GIS of beijing Beijing 100037 China

Ages of the stratigraphic boundary MIS1/2 and MIS3.4.of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2 and MIS3.4.are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2 is 11.5 kaB.P. and MIS3.4.is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3. 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14. age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2,3. WANG Pengxin4. YANG Hua1,2,3. LIU Shaomin1,2,3.& WANG Jindi1,2,3.1. Research Center for Remote Sensing and GIS, School of Geography, {4. normal university,{3., china 2. State Key Laboratory of Remote Sensing Science,{3., china 3. {4. Key Laboratory for Remote Sensing of environment and Digital Cities,{3., china 4. Department of Information Management, college of Information and Electronic Engineering, china Agricultural university, {4. 100083. china Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Beijing China beijing Key Laboratory for Remote Sensing of environment and Digital Cities Beijing China Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model

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Science china Earth Sciences 2005年第11期48卷 1979-1989页

作者： HE Chunyang, SHI Peijun, CHEN Jin, Li Xiaobing, PAN Yaozhong, LI Jing, LI Yuechen & LI Jinggang Key Laboratory of environmental Change and Natural Disaster, Ministry of Education of china, beijing {3. {4. college of resources Science & Technology, beijing {3. {4., beijing 100875, china Key Laboratory of environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University China college of resources Science & Technology Beijing Normal University Beijing China

Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are helpful to understanding the interactive mechanism between land use system and ecological system. A Land Use Scenario Dynamics (LUSD) model by the integration of System Dynamics (SD) model and Cellular Automata (CA) model is developed with land use scenario changes in northern china in the next 20 years simulated in this paper. The basic idea of LUSD model is to simulate the land use scenario de-mands by using SD model at first, then allocate the land use scenario patterns at the local scale with the considerations of land use suitability, inheritance ability and neighborhood effect by using CA model to satisfy the balance between land use scenario demands and supply. The application of LUSD model in northern china suggests that the model has the ability to reflect the complex behavior of land use system at different scales to some extent and is a useful tool for assessing the potential impacts of land use system on ecological system. In addition, the simulated results also indicate that obvious land use changes will take place in the farming-pastoral zone of northern china in the next 20 years with cultivated land and urban land being the most active land use types.

关键词： system dynamics, cellular automata, scenario, land use, model

Scenario simulation and forecast of land use/cover in northern china

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Chinese Science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3.& HE ChunYang 3.1 college of Geographical Science, Chongqing normal {4., Chongqing 4.004.,{3. 2 college of resources and environmental Science, Chongqing {4., Chongqing 4.004.,{3. 3.college of resources Science & Technology, {14. normal {4., beijing 100875,{3. college of Geographical Science Chongqing Normal University Chongqing China college of resources and environmental Science Chongqing University Chongqing China college of resources Science & Technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 3. years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74.. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

Cloning, sequencing and expression of the coat protein gene of Cocksfoot mottle virus

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Progress in Natural Science:Materials International 2007年第2期17卷 222-225页

作者： DONG Zhi, GUO Xiaoyu, ZHANG Hailong and ZHANG Feiyun ( college of Life Science, Capital normal university, {3. 10003., china college of resources environment and Tourism, Capital normal university, {3. 10003., china {3. Key Laboratory for resources environment and Geography Information System, {3. 10003., china) college of Life Science Capital Normal University Beijing 100037 China

The coat protein (CP) gene of Cocksfoot mottle virus (CfMV) was amplified by RT-PCR and inserted into expression vector pGEX-4.-1, and the resulting plasmid was designated as pGEXCfMV-JANCP. The fusion protein GST-CP was expressed in BL21 (DE3. pLysS after IPTG induction. The results of SDS-PAGE and Western blot analysis showed that the CfMV-CP gene was efficiently expressed in E. coli BL21 (DE3. pLysS through IPTG induction and the 56.0 kD protein was obtained.

关键词： Cocksfoot mottle virus sequence analysis prokaryotic expression.

Node ordinal encoded genetic algorithm for the optimal allocation of water resources

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Progress in Natural Science:Materials International 2005年第5期15卷 448-452页

作者： YANG Xiaohua1*, YANG Zhifeng 1,2, SHEN Zhenyao1 and LI Jianqiang3.1. State Key Laboratory of Water environment Simulation, School of environment, beijing {3. university, beijing 100875, china 2. Key Laboratory for Water and Sediment Sciences Ministry of Education, School of environment, beijing {3. university, beijing 100875, china 3. Water {13. and Hydropower Planning and Design General Institute, MWR, beijing 100011, china) State Key Laboratory of Water environment Simulation School of Environment Beijing Normal University Beijing 100875 China Key Laboratory for Water and Sediment Sciences Ministry of Education School of Environment Beijing Normal University Beijing 100875 China Water resources and Hydropower Planning and Design General Institute MWR Beijing 100011 China

A new method, node ordinal encoded genetic algorithm (NOEGA), is proposed for solving water resources optimal allocation problems, in which the capacity of water resources is split into a number of smaller parts so that successive operations can be overlapped. Our objective is to maximize the whole benefit function. To overcome the “dimensionality and algorithm complexity curse” while searching for solutions and looking for an optimal solution, the operations of one-point crossover operator, gene exchange operator, gene random operator, gene shift operator and node ordinal strings are established. It is proved to be an effective optimal method in searching for global solutions. The NOEGA does not need a diversity of initial population, and it does not have the problem of immature convergence. The results of two cases show that using NOEGA to solve the optimal allocation model is very efficient and robust. In addition, the algorithm complexity of NOEGA is discussed.

关键词： water resources optimal allocation node ordinal code genetic algorithm.