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^(13.)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

Pedosphere 2011年第1期21卷 37-45页

作者： LI Hao ZHANG Xin-Bao WANG Kc-Lin WEN An-Bang Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 (China) graduate University Chinese Academy of Sciences Beijing 100049 (China) State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-13.(13. Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 13. Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 13. Cs redistribution in a karst area of Southwest *** results indicated that the 13. Cs inventories of the surface soil on the slope studied were much lower than that of the local 13. Cs reference inventory and the 13. Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 13. Cs inventories was characterized by considerable *** high 13. Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 13. Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 13. *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 13. Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^13.Cs fallout, ^13.Cs inventory karst area runoff

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An efficient chiral synthesis of (R)-N-[3.acetyl-4.(2-hydroxy-3.isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2 & TANG XinLiang1,3.1 Technical Institute of Physics and Chemistry,chinese academy of sciences,Beijing 100080,{3. 2 College of Chemistry and Chemical Engineering,{4. University of chinese academy of sciences,Beijing 10004.,{3. 3.school of Chemical Engineering and Environment,Beijing Institute of Technology,Beijing 100081,{3. 1. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. school of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3.acetyl-4.(2-hydroxy-3.isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13. NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

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The Koppelman-Leray formula on complex Finsler manifolds

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Science china Mathematics 2005年第6期48卷 847-863页

作者： QIU Chunhui & ZHONG Tongde school of Mathematical sciences, Xiamen University, Xiamen 3.1005, china {3. of Mathematics and System sciences, chinese {3. of sciences, Beijing 100080, china 1. school of Mathematical sciences Xiamen University 361005 Xiamen China 2. academy of Mathematics and System sciences Chinese Academy of Sciences 100080 Beijing China

By means of the invariant integral kernel (the Berndtsson kernel), the complex Finsler metric and the non-linear connection associated with the Chern-Finsler connection to research into the integral representation theory on complex Finsler manifolds, theKoppelman and Koppelman-Leray formulas are obtained, and the - -equations are solved.

关键词： complex Finsler manifold, Chern-Finsler connection, invariant integral kernel, Koppelman-Lerayformulas, - -equation.

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Electronic structure and magnetism of Fe-doped SiC nanotubes

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2,3.ZHANG FuChun3.ZHANG ZhiYong4.LU ShuYuan5 & YANG YanNing3.1 Xi’an Institute of Optics and Precision Mechanics,chinese academy of {3.,Xi’an 710068,china 2 {4. University of chinese academy of {3.,Beijing 10004.,china 3.College of Physics and Electronic Information,Yan’an University,Yan’an 716000,china 4.Information Science and Technology Institution,Northwest University,Xi’an 710127,china 5 Department of Telecommunications,Xi’an Institute of Posts and Telecommunications,Xi’an 710121,china 1. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710068 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. College of Physics and Electronic Information Yan’an University Yan’an 716000 China4. Information Science and Technology Institution Northwest University Xi’an 710127 China5. Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an 710121 China

The electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).The calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is 3.2 eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si 3. electron spins and Fe 3. electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired 3. electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties

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Nitrogen isotopic composition of plant-soil in the Loess Plateau and its responding to environmental change

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chinese Science Bulletin 2009年第2期54卷 272-279页

作者： LIU WeiGuo1,2 & WANG Zheng1,3.1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, chinese academy of sciences, Xi’an 710075,{3. 2 Xi’an Jiaotong University, {4. of Human Settlement and Civil Engineering, Xi’an 71004.,{3. 3.graduate University of chinese academy of sciences, Beijing 10004.,{3. chinese Acad Sci Inst Earth Environm State Key Lab Loess and Quaternary Geol Xian 710075 Peoples R China.

The nitrogen isotope of soil is of emerging significance as an indicator of climatic change and biogeochemical cycle of nitrogen in nature systems. In this paper, the nitrogen content and isotopic composition of modern ecosystems from arid and semiarid Loess Plateau in northwestern china, including plant roots and surface soil, were determined to investigate trends in δ15N variation of plant roots and soil along a precipitation and temperature gradient in northwestern china under the East Asian Monsoon climate condition. The δ15N values of surface soil from the study area vary from ?1.2‰ to 5.8‰, but from -5.1‰ to 1.9‰ in the plant roots. Our results indicate that (1) although the isotopic compositions of both plant roots and surface soil change with a similar trend along the climate gradient, the apparent nitrogen difference between plant roots and soil existed, with -δ15N values ranging from 0.3. to 7.2‰ with average of 4.1‰; and (2) mean annual precipitation (MAP) is the dominant factor for isotopic composition of plant-soil nitrogen in the Loess Plateau, and the δ15N values are less correlated with MAT; we suggest that nitrogen isotopic composition of soil is a potential tracer for environmental changes.

关键词：氮同位素物理性质化学性质环境论

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Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of Jinan, china

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chinese Journal of Population,Resources and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1, 3. Zhang Zulu2, Jiang Luguang 1 1. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101,{4. 2. College of Population, Resources and Environment, Shandong Normal University, Jinan Shandong 250014.{4. 3. graduate school of the chinese academy of sciences, Beijing 10003.,{4. Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China graduate school of the chinese {3. of {4. Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1986 and 2004. the spatial structure of Jinan is studied in this paper with the method of Geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1986 to 2004. great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

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Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese Science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3.LIU XiaoDong 4.& TIAN ZhiPing 2,5 1 Climate Change Research Center,chinese academy of {3.,Beijing 100029,china 2 Nansen-Zhu International Research Centre,Institute of Atmospheric Physics,chinese academy of {3.,Beijing 100029,china 3.Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,chinese academy of {3.,Beijing 100029,china 4.State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,chinese academy of {3.,Xi’an 710075,china 5 graduate University of chinese academy of {3.,Beijing 10004.,china 1. Climate Change Research Center Chinese Academy of Sciences Beijing 100029 China 2. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China 4. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. graduate University of chinese academy of {3. Beijing 100049 China

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4. developed at the National Center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

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Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3.1 Department of Earth sciences, Nanjing University, Nanjing 210093. china 2 Guangzhou Institute of Geochemistry, chinese {3. of sciences, Guangzhou 51064., china 3.graduate University of chinese {3. of sciences, Beijing 10004., china Department of Earth sciences Nanjing University Nanjing 210093 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China graduate University of chinese academy of {3. Beijing 100049 China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

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Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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Science china Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2, WANG Jin3. WU Yishi1, YUAN Gu3. AI Xicheng1, WANG Li4.& ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, chinese academy of {3., Beijing 100080, china 2. {4. of Life Science and Technology, Beijing Institute of Technology, Beijing 100081, china 3. College of Chemistry and Molecular Engineering, Peking University, Beijing 100080, china 4. Center for Condensed Matter Physics, Institute of Physics, chinese academy of {3., Beijing 100080, china Correspondence should be addressed to Ai Xicheng and Zhang Jianping 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. school of Life Science and Technology Beijing Institute of Technology Beijing 100081 China 3. College of Chemistry and Molecular Engineering Peking University Beijing 100080 China 4. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 3. ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

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Risk Analysis on Groundwater Resources Carrying Capacity Based on Blind Number Theory

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Wuhan University Journal of Natural sciences 2007年第4期12卷 669-676页

作者： ZHANG Ji1,2,YU Sujun3.. Key Laboratory of Mountain Hazards and Surface Process,chinese academy of sciences/Institute of Mountain Hazards and Environment,chinese academy of sciences,Chengdu 61004.,Sichuan,china 2. graduate University of the chinese academy of sciences,Beijing 10004.,china 3. school of Environmental Science and Engineering,Southwest Jiaotong University,Chengdu 61004.,Sichuan,china Key Laboratory of Mountain Hazards and Surface Process Chinese Academy ofSciences/Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041Sichuan China

Blind numbers of evaluation indices about groundwater resources carrying capacity are defined from the concomitancy of randomness, fuzziness, grey property and unascertainment of groundwater system. Based on fuzzy theory, a comprehensive evaluation model on groundwater resources carrying capacity is constructed with blind information. Then a risk assessment model of surcharge about groundwater resources carrying capacity is established on blind reliability theory. The probable value ＂＊＂ matrix of fuzzy membership degree about carrying capacity corresponding to each judgment level can be obtained with the aid of blind algorithm as well as the subjective reliability ＂×＂ matrix. And then a graph of ＂groundwater carrying capacity v.s. accumulative reliability＂ can be gained Based on the graph, fuzzy membership degree of groundwater resources carrying capacity to each judgment level under different risk probability can be got. Thus, a comparatively reasonable judgment to groundwater resources carrying capacity might be obtained, with comprehensive analysis to the state of society, economy technology and ecology.

关键词： blind number theory groundwater resources carrying capacity evaluation risk analysis

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