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Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern china

Science china Earth sciences 2006年第3期49卷 295-303页

作者： WANG Hongqiang1,2. DENG Chenglong1, ZHU Rixiang1 & XIE Fei3.1. Paleomagnetism and geochronology Laboratory (SKL-LE), Institute of geology and geophysics, Chinese Academy of Sci- ences, beijing 10002., china 2. School of the Earth sciences and resources, china university of geosciences, beijing 100083, china 3. Hebei Province Institute of Cultural Relics, Shijiazhuang 050000, china 1. Paleomagnetism and geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. School of the Earth sciences and resources China University of Geosciences Beijing 100083 China 3. Hebei Province Institute of Cultural Relics Shijiazhuang 050000 China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern china, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1 Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3.and 1.1 Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.

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Improving the accuracy of image-based forest fire recognition and spatial positioning

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Science china(Technological sciences) 2010年第S1期53卷 184-190页

作者： JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2.& CHENG Xi 1,3.1 Institute of geographical sciences and Natural {2. Research,Chinese Academy of sciences,beijing 100101,china 2.6} Center for {2. Satellite Data and Applications,beijing 100094,china 3.raduate university of Chinese Academy of sciences,beijing 100049,china Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China china Ctr resources Satellite Data & Applicat Beijing 100094 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

Forest fires are frequent natural *** is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest *** paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial ***,we discuss a method of forest fire recognition in visible-light *** are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2.excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3.improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image ***,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature ***,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central *** studies are examined and the results are found to be satisfactory.

关键词： forest fire monitoring spatial positioning accuracy improvement

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Critical slope gradient for compulsory abandonment of farmland on the hilly Loess Plateau

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Chinese Science Bulletin 1998年第5期43卷 409-412页

作者： TANG Keli+1, ZHANG Keli 1,2.and LEI Aling 1,3.1. Institute of Soil and Water Conservation, Chinese Academy of sciences, Yangling 712.00,{3. 2. Department of Hydraulic Engineering, Tsinghua {2., beijing 100084,{3. 3. Water resources C Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling China Department of Hydraulic Engineering Tsinghua University Beijing China Water resources Conservation Bureau of Yangtze River Ministry of Water Resources Wuhan China

Scientific evidence for the upper limit of farmland is proposed. Shallow gully erosion is one of erosion types distributed extensively on sloping farmland in the hilly regions of the Loess Plateau. Field observation and aerial photos interpretation, as well as laboratory experiments show that the shallow gully erosion occurring on the steeper farmland in the hilly regions of the Loess Plateau is an important factor leading to intensive erosion on slope, because of its extensive distribution and intensive runoff collection. The data on the formation, development and distribution of shallow gullies on sloping farmland indicate that critical slope gradient for shallow gully initiation ranges from 15 to 2. degrees with an average of 18.2.degrees. Therefore, it is suggested that critical slope gradient for compulsory abandonment of farmland on the hilly Loess Plateau should be kept within the critical slope gradient for shallow gully initiation to prevent shallow gully formation in order to control soil loss more effectively. But as the first step, the cultivation on the slopes with slope larger than 2. degrees where the maximum erosion occurs should be strictly forbidden.

关键词： hilly region of Loess Plateau upper limitation for farmland shallow gully erosion erosion dynamic.

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Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2.Zhao-Feng JIANG~2. 1 College of Life Science,Capital Normal university,{3. 10003.,{2. 2.College of Applied sciences and Humanities,{3. Union university,{3. 100083,{2. College of Life Science Capital Normal UniversityBeijing 100037 China College of Applied sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2.and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

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Discovery of submicron diamonds within kimberlite in Liaoning Province, china and its significance

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Chinese Science Bulletin 1997年第11期42卷 939-941页

作者： BAO Yanan, T. V. Dubuchick and T. D. Liabchekov1. Graduate School in beijing, Chinese Mining university,{2.,{3. 2. Moscow resources Institute of Mineral Materials, Russia 3. resources Institute of Deposit geology, Russian Academy of sciences, Russia Graduate School in beijing Chinese Mining University Beijing China Moscow resources Institute of Mineral Materials Russia resources Institute of Deposit geology Russian Academy of Sciences Russia

ALTHOUGH a lot of research work on diamond mineralogy has already been done,the formationand development of diamond leave much to be *** have done some researches onthe diamond samples with obvious crystal-growing cha... 详细信息

关键词： submicron diamond lath-shape aggregative parent material.

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Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2.3.1. National Marine Environmental Forecasting Center, beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of {2., beijing 10002., china 3. Graduate university of Chinese Academy of {2., beijing 100049, china 1. National Marine Environmental Forecasting Center Beijing 100081 China 2. Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Graduate university of Chinese Academy of sciences Beijing 100049 China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

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The steady-state solution of dendritic growth from the undercooled binary alloy melt with the far field flow

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Science china(Technological sciences) 2009年第8期52卷 2280-2287页

作者： CHEN MingWen1,2. WANG ZiDong2.& XU JianJun2.3.4 1 School of Applied {3., university of Science and Technology {2., beijing 100083, china 2.School of Materials Science and Engineering, university of Science and Technology {2., beijing 100083, china 3.School of Mathematical {3., Nankai university, Tianjin 3.0071, china 4 Department of Mathematics and Statistics, McGill university, Montreal H3. 2.6, Canada School of Applied sciences University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Mathematical sciences Nankai University Tianjin 300071 China Department of Mathematics and Statistics McGill University Montreal H3A 2K6 Canada

The steady-state dendritic growth from the undercooled binary alloy melt with the far field flow is considered. By neglecting the interface energy, interface kinetics and buoyancy effects in the system, we obtaine the steady-state solution for the case of the large Schmidt number, in terms of the multiple variable expansion method. The changes of the temperature and concentration fields, the morphology of the interface, the normalization parameter and the Peclet number of the system induced by uniform external flow are derived. The results show that, compared with the system of dendritic growth from undercooled pure melt, the convective flow in the system of growth from undercooled binary alloy has stronger effects on the morphology of the interface. Nevertheless, the shape of the interface still remains nearly a paraboloid.

关键词： binary alloy melt convection dendritic growth interfaces steady-state solution multiple variable expansion method

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Plus cupping degrees do not form an ideal

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Science in china(Series F) 2004年第5期47卷 635-654页

作者： LI Angsheng1,2.& ZHAO Yicheng1 1. Institute of Software,Chinese Academy of sciences,beijing 100080,{2. 2. School of Information sciences,beijing Normal university,beijing 100871,{2. 1. Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. School of Information sciences Beijing Normal University 100871 Beijing China

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0 详细信息

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0

关键词： computably enumerable set Turing degree definability.

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N_2. emissions from agricultural soils in the North china Plain: the effect of chemical nitrogen fertilizer and organic manure

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Journal of Environmental sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1,2.3., Dieter Scharffe 2. Manfred Domroes 3. QI Yu chun 1, ZHANG Shen 1 (1. Institute of geographic {3. and Natural {2. Research, Chinese Academy of {3., beijing 100101, china E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-Institute of Chemistry 德国 Mainz 550 2 0 Mainz university 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2. emissions from intensively agricultural soils of the North china Plain during the periods of 1995—1996 and 1997—1998, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2. emissions by a factor of 2..1—2..1, the calculated annual chemical N fertilizer\|transformed N\-2.\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2. emissions, which combined with the use of chemical N increased about 2.% in a year. It was calculated that there were about 0.11% N of organic manure transformed as N 2. N. Annual mean N 2. emission from our study area of fertilized soils was estimated to be 57.1 μgN 2./(m 2.h). A weak correlation was also found between N 2. emissions and soil available nitrogen content NH + 4.

关键词： N_2. emissions the North china Plain agricultural soils chemical nitrogen organic manure

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Modeling and verifying Web services driven by requirements:An ontology-based approach

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Science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3.JIN ZHi1,2.& WU Budan1,4 1. Academy of Mathematics and Systems Science, Chinese Academy of sciences, beijing 100080,{2. 2. Institute of Computing Technology, Chinese Academy of sciences, beijing 100080,{2. 3. Institute of Software, Chinese Academy of sciences, beijing 100080,{2. 4. Graduate university of Chinese Academy of sciences, beijing 100049,{2. 1. Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China 3. Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. Institute of Computing Technology Chinese Academy of Sciences Bejing 100080 China 4. Graduate university of Chinese Academy of sciences Beijing 100049 China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

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