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A contrast of two typical LUCC processes and their driving forces in oases of arid areas: A case study of Sangong River Watershed at the northern foot of Tianshan Mountains

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Science china Earth sciences 2007年第S1期 65-75页

作者： TANG FaShu1,2, CHEN Xi1, LUO GePing1, LIN Qing1,2 & LIU HaiLong1,2 1 Xinjiang institute of Ecology and Geography, chinese academy of sciences, ürümqi 83.011, china 2 Graduate University of chinese academy of sciences, beijing 100049, china

Aerial photographs taken in 1978 and 1987, Landsat TM images in 1998 as well as soil, hydrology and socio-economic data for the oases in Sangong River Watershed were processed by Remote Sensing (RS) and Geographic Information System (GIS). There are two typical agricultural land uses in oases, Farm-based Land Use with large-scale intensified agricultural activities (FLU) and Household Respon-sibility-based Land Use with small-scale activities (HRLU). The Index Model of Land Use/Land Cover Change (LUCC), Weighted Index Sum (WIS) and logistic stepwise regression model were estab-lished to contrast the two typical LUCC processes and their driving forces. The land use patterns were dominated by cropland and grassland for the entire region, and cropland, residential and industrial land were increasing stably. In the HRLU areas, woodland and grassland declined dramatically, but in the FLU areas, grassland decreased only by 12.0%, whereas woodland increased by 13.7%. LUCC was stronger in the earlier stage (1978-1987) than in the later stage (1987-1998) for the entire region. LUCC was more intense in the HRLU areas than in the FLU areas during the entire period (1978-1998). Policy was a key factor in the land use change, and water resources were a precondition in land use. Under the control of policy and water resources, the main human driving factors included population and economy, and the main natural restrictions were soil fertility and groundwater depth. Human driving factors controlled the land change in the HRLU areas, but natural restriction factors dominated in the FLU areas. In the mean time, intensification of LUCC in the region had some spatiotemporal implications with a fluctuation of impact factors.

关键词： oases land use driving forces Sangong River logistic

Cloning and functional analysis of chloroplast division gene NtFtsZ2-l in Nicotiana tabacum

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Progress in Natural Science:Materials International 2003年第5期 39-43页

作者： KONG Dongdong , JU Chuanli, WANG Dong, HU Yong, ZHU Zhiqing, HE Yikun and SUN Jingsan (1. Key Laboratory of Photosynthesis and Enviromental Molecular Physiology, institute of Botany, chinese academy of sciences, beijing 100093. {3. 2. Department of Biology, Capital Normal University, beijing 10003., {3. 3. Laboratory of Agronomy and Biotechnology, {3. Agricultural University, beijing 10003., {3. 4. College of Life sciences, beijing Normal University, beijing 100875, {3.)

FtsZ protein plays an important role in the division of chloroplasts. With the finding and functional analysis of higher plant FtsZ proteins, people have deepened the understanding in the molecular mechanism of chloroplast division. Multiple ftsZ genes are diversified into two families in higher plants, ftsZ1 and ftsZ2 . On the basis of the research on ftsZl family, we analyzed the function of NtFtsZ2-l gene in Nicotiana tabacum . Microscopic analysis of the sense and antisense NtFtsZ2-l transgenic tobacco plants revealed that the chloroplasts were abnormal in size and also in number when compared with wild-type tobacco chloroplasts. Our investigations confirmed that the NtFtsZ2-l gene is involved in plant chloroplast division.

关键词： Nicotiana tabacum NtFtsZ2-l gene chloroplast division.

Microexplosion textures in mantle rocks:A possible cause of deep-focus earthquakes

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Microexplosion textures in mantle rocks:A possible cause of ...

2004年全国岩石学与地球动力学研讨会

作者： Wen-ji Bai, Jingsui Yang, Qing-song Fang, Zhong-ming Zhang and Bing-gang Yan (institute of geology, chinese {3. of Geological sciences, beijing 10003.,china)

＜正＞ Microexplosion textures have been recognized in silicate minerals in chromitites of the Luobusa ophiolite, Tibet. These consist of minute fragments of brecciated chromite embedded in a matrix of serpentine or chlorite. In some cases, the serpentine and chlorite forms euhedral pseudomorphs after the original silicate grains;in others the original morphology has been completely obliterated. The original minerals are believed to have been hydrous magnesium and magnesium aluminum silicates. Many unexploded grains have octahedral morphologies suggesting that they may originally have had spinel or perovskite structures, indicating formation deep within the mantle. The explosion textures are believed to have formed when the original hydrous silicate minerals were carried upward and crossed the ’water line’, causing an explosive release of lattice water. The explosive disintegration of numerous silicate minerals may be responsible for some deep-focus earthquakes.

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用相对行标尺量模型分析中国经济结构的转变

系统工程理论与实践 2003年第10期23卷 43-47,75页

作者：李景华中国科学院数学与系统科学研究院系统科学研究所北京100080

为了测度经济结构变动及其主要影响因素,构造了一个基于投入产出技术的相对行标尺量(Relative Rowscaler)模型,它将经济结构的变动分解为技术系数和最终需求结构系数的变动,并应用该模型对中国1981-1995年间经济结构转变情况作出了实证... 详细信息

为了测度经济结构变动及其主要影响因素,构造了一个基于投入产出技术的相对行标尺量(Relative Rowscaler)模型,它将经济结构的变动分解为技术系数和最终需求结构系数的变动,并应用该模型对中国1981-1995年间经济结构转变情况作出了实证定量分析.主要结论是这一阶段我国经济结构发生了显著变化,主要影响因素是技术系数的变动,但最终需求结构因素的拉动作用日渐增强。

关键词：经济结构行标尺量(Rowscaler) 结构分解投入产出

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Research progress in synthesis and catalysis of polyoxometalates

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Progress in Natural Science:Materials International 2005年第5期15卷 385-394页

作者： GONG Yun1, HU Changwen1* and LIANG Hong2(1. Department of Chemistry, School of Science, the institute for Chemical Physics, beijing institute of Technology, beijing 100081, china 2. Chemical Industry Press, beijing 10002., china) Department of Chemistry School of Science the Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China Chemical Industry Press Beijing 100029 China

Recent progress in the synthetic chemistry and catalysis of polyoxometalates (POMs) is reviewed. The novel POMs and their derivatives emerging in nearly three years (2002—2004) are introduced, including POMs with novel structure, POMs-organic hybrid compounds and host-guest complexes. Our review is focused on the elaboration of POMs' supramolecular chemistry.

关键词： polyoxometalates hybrid host-guest structure supramolecule catalysis.

Intercalibration of internatioal and domestic 40Ar/3.Ar dating standards

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Intercalibration of internatioal and domestic 40Ar/39Ar dati...

中国科学院地质与地球物理研究所2006学术年会

作者： Wang Fei,He Huanyu,ZHU Rixiang,SANG Haiqing,WANG Yinglan,YANG Liekun institute of geology and geophysics,{3. academy of Science,beijing 10002.

Four international standards,Gal 550,MMhb-1,Lp-6,Bern 4M,and one domestic standard BT-1 have been *** repeated measurements on MMhb-1 with different mass demonstrate that MMhb-1 is inhomogeneous in age and the average age of 519.8Ma of it is *** results of Bern 4M and Lp-6 reflect they have invariable value of Ar*/Ar(F) and the ages we obtained are consensus with their K-Ar age:Lp-6=127.7Ma;Bern 4M=18.2Ma. Analyses of BT-1 age spectra,Ca/K and Cl/K spectra as well as inverse isochrons indicate that the sample is homogeneous and invariable and keep close chemically,with its trapped argon isotope composition close to the *** dating results show age values are reproducible and steady,its total fusion age,step-heating age,plateau age and isochron age are in accordant with each other within the error range(2a).Therefore,we recommend 28.7Ma as the calibrated age of BT-1. We also discuss the variation in neutron flux gradients of beijing 49-2 *** was found that the neutron flux gradient varies considerably,and more monitors(standard samples) are needed to fix the trend of *** coefficient of the 49-2 reactor that transfer the ratio of production rate of Ar/Ar into Ca/K ratio is *** is different from 2.0 reported earlier, which may be caused by the reconstruction of the reactor.

关键词： 40Ar/3.Ar dating standards Intercalibration 49-2 reactor

NEW DISCOVERIES OF LONGFENGSHANIACEAE FROM THE UPPERMOST EDIACARAN IN THE EASTERN YUNNAN, SOUTH china

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NEW DISCOVERIES OF LONGFENGSHANIACEAE FROM THE UPPERMOST EDI...

第二届国际古生物学大会

作者： Feng TANG Chongyu YIN Pengju LIU Xueliang SONG Ziqiang WANG Linzhi GAO institute of geology chinese {3. of Geological sciences beijing 10003. china. institute of Geosciences Yunnan Province Kunming 650051 china china University of Geosciences beijing 100083.china

＜正＞A morphologically more diverse assemblage of Longfengshaniaceae has been found in the uppermost Ediacaran （Sinian） Jiucheng Member, Yuhucun Formation at Jinning and Jiangchuan County, eastern Yunnan, South china. A majority,of them are different from the Longfengshania in the Neoproterozoic Changlongshan Formation, Yanshan Mountain Area, North china and the Mesoproterozoic Little Dal Group, North America. They are mainly characterised by a more varied, often thallus-like appearance, such as shuttle-shaped, jujube nucleus-shaped, shovel-shaped, ribbon-shaped or balloon-shaped, and more sturdy stalk-like projection （stipe） with a smooth connection on the basal part of the thallus. In addition, they appear to have a remarkable attaching organ of lanceolate, shuttle-like or short stem-like structure at the base of the stipe. Six distinct morphological taxa are recognised, including one new

关键词： the eastern Yunnan Ediacaran Jiucheng Member Longfengshaniaceae

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曙光作业管理系统的可用性评价

系统仿真学报 2007年第A1期19卷 227-232页

作者：何昱历军聂华中国科学院计算技术研究所中国科学院研究生院北京100080 曙光公司北京100084

针对持续发展的高性能计算带来的新需求,我们设计与实现了DCJM机群作业管理系统,并使用了多种高可用保障措施。为了验证其有效性,综合使用可靠性框图、故障树和随机Petri网等工具对DCJM建模,然后基于实际测量的参数,使用统一的模型求解... 详细信息

针对持续发展的高性能计算带来的新需求,我们设计与实现了DCJM机群作业管理系统,并使用了多种高可用保障措施。为了验证其有效性,综合使用可靠性框图、故障树和随机Petri网等工具对DCJM建模,然后基于实际测量的参数,使用统一的模型求解,对系统可用性进行了完整的评价。分析结果显示DCJM系统达到了高可用性。

关键词：作业管理系统可用性评价可靠性框图故障树随机Petri网

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Bonding and Fracture Characteristics at α_2/γ Interface in TiAl Alloy with B Addition

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Journal of Materials Science & Technology 1999年第1期15卷 43-47页

作者： Senying LIU Dongliang ZHAO Rongze HU and Chongyu WANG(Central Iron and Steel Research institute, beijing 100081, china)Ping LUO(National Research Center for CRM, beijing 100013. china) Central Iron and Steel Research institute Beijing 100081 China National Research Center for CRM Beijing 100013 China

The bonding characteristics of (0001)α2||(111)γ interface in two-phase TiAl alloy have beeninvestigated with the recursion method. The results of bond order integral and interaction energybetween atoms are presented. The effects of B on atoms bonding both in constituent phase andat the α2/γ interface have been studied. The correlation between the mechanical propertiesof the alloy and the bonding at the interface has been discussed. The results suggest that Bsegregation to the interface benefits the ductility. This is supported by the related experiment.

关键词： TiAl Bonding and Fracture Characteristics at Interface in TiAl Alloy with B Addition

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