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

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 100037, china 2. Key Laboratory of 3D information Acquisition and Application, The capital normal university, beijing 100037, china 3. Department of Economics & Management of Huizhou university, Huizhou 516007, china 4. Key Laboratory of Western china’s environmental Systems, Ministry of Education, Lanzhou university, Lanzhou 730000, china) MOE and Key Laboratory of resources environment and GIS of beijing Beijing 100037 China Key Laboratory of 3D information Acquisition and Application The Capital Normal University Beijing 100037 China Department of Economics & Management of Huizhou university Huizhou 516007 China Key Laboratory of Western china’s environmental Systems Ministry of Education Lanzhou University Lanzhou 730000 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 AMS14C 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

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Estimation of net primary productivity in china using remote sensing data

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Journal of Geographical Sciences 2001年第1期11卷 14-23页

作者： SUN Rui, ZHU Qi-jiang (Dept. of resources and environment Sciences, beijing normal university, beijing 100875, china) Dept. of resources and environment Sciences Beijing Normal University Beijing China

It is significant to estimate terrestrial net primary productivity (NPP) accurately not only for global change research, but also for natural resources management to achieve sustainable development. Remote sensing data can describe spatial distribution of plant resources better. So, in this paper an NPP model based on remote sensing data and climate data is developed. And 1km resolution AVHRR NDVI data are used to estimate the spatial distribution and seasonal change of NPP in china. The results show that NPP estimated using remote sensing data are more close to truth. Total annual NPP in china is 2.645X109 tC. The spatial distribution of NPP in china is mainly affected by precipitation and has the trend of decreasing from southeast to northwest.

关键词： remote sensing net primary productivity vegetation model seasonal change

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New fossil elaterids(Insect:Coleoptera:Polyphaga:Elateridae) from the Middle Jurassic of Inner Mongolia,china

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Progress in Natural Science:Materials International 2009年第10期19卷 1433-1437页

作者： Huali Chang,Yunyun Zhao,Dong Ren college of Life Science,capital normal university,beijing 100048,china [a]college of Life Science Capital Normal University Beijing 100048 China

A new genus with a new species of fossil elaterid,Paraprotagrypnus superbus *** ***.,from the Middle Jurassic Jiulongshan Formation in Daohugou Village(N41°18.9790,E119°14.3180),Shantou Township,Ningcheng County,Inner Mongolia,china is described and *** genus Paraprotagrypnus belongs to the family of Elateridae,subfamily of Protagrypninae and tribe of *** primitive characters of the new genus and new species shed light on the ages between the Jiulongshan Formation in Inner Mongolia and the Yixian Formation in the western Liaoning Province of *** habitat of the new species is briefly discussed.

关键词： Elateridae New genus Paraprotagrypnus superbus sp.nov. Middle Jurassic Jiulongshan Formation china

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A COUPLED MODEL OF HYDRODYNAMICS AND WATER QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun School of environment Beijing Normal University Beijing 100875 China Department of Water environment China Institute of Water Resources and Hydropower Research Beijing100038 China Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 44.0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

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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 normal university, beijing 100875, china Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, china) [a]college of resources Sciences & Technology Beijing Normal University Beijing China [b]Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Lanzhou 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 δ13C1 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 - 333‰ to - 117‰, and δ13CCO2 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 δ13C1 and δ13CCO2 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 δ13C1 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.

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Trend,seasonal and diurnal variations of atmospheric CO_2 in beijing

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Chinese Science Bulletin 2002年第24期47卷 2050-2055页

作者： WANG Yuesi, WANG Changke, GUO Xueqing, LIU Guangren & HUANG YaoLAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100083, china Department of Chemistry, capital normal university, beijing 100037, china LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Chemistry Capital Normal University Beijing China

The concentration of atmospheric CO2 in beijing increased rapidly at a mean growth rate of 3.7%·a-1 from 1993 to 1995. After displaying a peak of (409.7±25.9) μmol·mol-1 in 1995, it decreased slowly. Both the almost stable anthropogenic CO2 source and increasing biotic CO2 sink contribute to the drop of CO2 concentration from 1995 to 2000. The seasonal variation of CO2 concentration exhibits a clear cycle with a maximum in winter, averaging (426.8± 20.6)μmol·mol-1, and a minimum in summer, averaging (369.1±6.1)μmol·mol-1. The seasonal variation of CO2 concentration is mainly controlled by phenology. The mean diurnal variation of atmospheric CO2 concentration for a year in beijing is highly clear: daily maximum CO2 concentration usually occurs at night, but daily minimum CO2 concentration does in the daytime, with a mean diurnal difference more than 34.7μmol·mol-1. It has been revealed that the interannual variations of atmospheric CO2 concentration in winter and autumn regulated the

关键词： atmospheric CO2 annual variation seasonal variation diurnal variation urban environment.

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Study on Human capital Valve Quantity Model and Investment Featuers

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Chinese Journal of Population,resources and environment 2005年第1期3卷 49-54页

作者： Chen Peian, Li Yujiang & Li Zhen Population, resources and environment college, Shandong normal university, Jinan Shandong 250014, china Population Resources and Environment College Shandong Normal University Jinan Shandong 250014 China

In this paper, human capital is considered a kind of goods in terms of investment. Basic consumption and profit margin are the two important components of human capital goods value. Compared with that of the material capital, the human capital consumption has the following features. The importance of human capital investment determined by the supply-demand mechanism, is growing gradually; The course of investment and return takes a long period of time; Human capital is characterized by strong technicality and weak negotiability; The investment profit margin is changeable and discriminating.

关键词： human capital value measure profit margin

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Content-based similarity for 3D model retrieval and classification

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Progress in Natural Science:Materials International 2009年第4期19卷 495-499页

作者： Ke Lüa, Ning He b, Jian Xue a a college of Computing & Communication Engineering, Graduate university of Chinese Academy of Sciences, Yuquan Road 19(A), beijing 100049, china b School of Mathematical Science, capital normal university, beijing 100037, china [a]college of Computing & Communication Engineering Graduate University of Chinese Academy of Sciences Yuquan Road 19(A) Beijing 100049 China [b]School of Mathematical Science Capital Normal University Beijing 100037 China

With the rapid development of 3D digital shape information, content-based 3D model retrieval and classification has become an important research area. This paper presents a novel 3D model retrieval and classification algorithm. For feature representation, a method combining a distance histogram and moment invariants is proposed to improve the retrieval performance. The major advantage of using a distance histogram is its invariance to the transforms of scaling, translation and rotation. Based on the premise that two similar objects should have high mutual information, the querying of 3D data should convey a great deal of information on the shape of the two objects, and so we propose a mutual information distance measurement to perform the similarity comparison of 3D objects. The proposed algorithm is tested with a 3D model retrieval and classification prototype, and the experimental evaluation demonstrates satisfactory retrieval results and classification accuracy.

关键词： 3D model Retrieval and classification Content-based 3D model retrieval Similarity comparison

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New dragonflies (Insecta: Odonata: Gomphaeschnidae) from the Yixian Formation in Inner Mongolia, china

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Progress in Natural Science:Materials International 2008年第1期18卷 59-64页

作者： Binglan Zhang a ,Dong Rena ,*,Hong Pang b acollege of Life Science,capital normal university,beijing 100037,china bState Key Laboratory of Biocontrol and Institute of Entomology,Sun Yat-sen university,Guangzhou 510275,china college of Life Science Capital Normal University Beijing 100037 China State Key Laboratory of Biocontrol and Institute of Entomology Sun Yat-sen University Guangzhou 510275 China

Two fossil dragonflies from the Upper Jurassic to Lower Cretaceous Yixian Formation in Liutiaogou Village,Ningcheng County, Inner Mongolia,china are described and *** are assigned to two new genera and species,i.e.,Sophoaeschna frigida gen. et *** Falsisophoaeschna generalis *** *** the family Gomphaeschnidae Tillyard&Fraser,*** is the first report of Odonata from Yixian Formation in Inner Mongolia and the second record of fossil Gomphaeschnidae from china.

关键词： Odonata New genus Upper Jurassic to Lower Cretaceous Yixian Formation china

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From the Green's Function in Tight-Binding Representation to Interatomic Many-body Potentials

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Journal of Materials Science & Technology 1999年第4期15卷 315-319页

作者： Shaojun LIU(Department of physics, beijing normal university, beijing 100875, china)Xiaobo WEI(Department of Physics, Liuzhou college of Education, Liuzhou 545005, china)Zhaodou CHEN Jun CAI and Benkun MA(Department of Physics, beijing normal university, beijing normal Univ Dept Phys Beijing 100875 Peoples R China Liuzhou Coll Educ Dept Phys Liuzhou 545005 Peoples R China

In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method.

关键词： Rev Li Chen From the Green’s Function in Tight-Binding Representation to Interatomic Many-body Potentials body

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