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Effects of Terracing and Agroforestry on Soil and Water Loss in Hilly Areas of the Sichuan Basin, china

Journal of Mountain Science 2008年第3期5卷 241-248页

作者： J.H. ZHANG Z.A. SU G.C. LIU key laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences 610041 China institute of Mountain Hazards and Environment Chinese Academy of Sciences ＆Ministry of Water Conservancy Chengdu 610041 China The graduate school of the{2. Beijing 100049 China

Soil erosion in hilly areas of the Sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3.year experiment was conducted using the method of runoff plots to examine the effects of terracing and agroforestry in farmland systems on soil and water conservation of slope fields in the hilly areas in Jianyang County, Sichuan Province, Southwestern china. A power function (Y = aXb) can statistically describe the relationship between water runoff (Y) and rainfall (X). The regression equation for the treatment of sloping terraces with crops (Plot 2. is remarkably different from that for the treatment of sloping terraces with grasses and trees (Plot 1) and the conventional up- and down-slope crop system (Plot 3. regarding equation coefficients, while regression equations are similar between Plot 1 and Plot 3. Water runoff amount and runoff coefficient of slope fields increased by 2..5～41.0 % and 2..5～69.7 % respectively, compared to those of sloping terraces, suggesting that terracing notably reduced the water runoff in the field. In the case of sloping terraces, lower amount of water runoff was observed on sloping terraces with crops than on sloping terraces with grasses and trees. Sediment yields on the slope fields in the normal year of rainfall distribution were notably higher (3..41～3.1.67 % and 3..06～403.44 % for Plot 1 and Plot 2. respectively) than those on sloping terraces, implying that terracing also plays a significant role in the reduction in soil erosion. It is suggested that terracing with crops is significantly effective for soil and water conservation in cultivatedfarmland, while the conventional practice of up- and down- slope cultivation creates high rates of water runoff and soil sediment transport. Terracing with grasses and fruit trees shows a less reduction in water runoff than terracing with crops, which was observed in the 3.year experiments.

关键词： Agroforestry sediment transport runoff sloping terrace soil and water conservation

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Highly stereospecific polymerization of isoprene with homogeneous binary Ziegler-Natta catalysts based on NCN-pincer neodymium precursor

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Science china Chemistry 2010年第8期53卷 1641-1645页

作者： LIU DongTao1,2.CUI DongMei1 & GAO Wei3.1State key laboratory of Polymer Physics and Chemistry Changchun {2. of Applied Chemistry,chinese academy of sciences,Changchun 13.02.,china 2.7} University of chinese academy of sciences,beijing 10003.,china 3.13. of Chemistry,Jilin University,Changchun 13.012.china State key laboratory of Polymer Physics and Chemistry Changchun institute of Applied Chemistry Chinese Academy of Sciences Changchun China graduate University of chinese academy of sciences Beijing China school of Chemistry Jilin University Changchun China

The aryldiimine NCN-pincer stabilized neodymium dichloride combined with aluminum alkyls established a new type of homogeneous binary neutral Ziegler-Natta catalyst *** system exhibited high activity and high cis-1,4 selectivity for the polymerization of isoprene (Tp=2. °C,98.2.;Tp=-2. °C,> 99%).Such catalytic performances remained under a broad range of polymerization temperatures and monomer-to-neodymium ratios (from 500 to 8000),reaching high number-average molecular weight (Mn=1582.kg/mol) and relatively narrow molecular weight distribution (PDI=1.68),which was,however,influenced by the amount and bulkiness of aluminum *** investigation of the polymerization was performed,which showed the number-average molecular weight of the resultant polyisoprene had an almost linear correlation with the conversion,suggesting,in some degree,the polymerization with this catalytic system was controllable.

关键词： neodymium cis-1 4 selectivity NCN-pincer complex polyisoprene

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A fingerprint identification algorithm by clustering similarity

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Science china(Information sciences) 2005年第4期48卷 437-451页

作者： TIAN Jie, HE Yuliang, CHEN Hong & YANG Xin Center for Biometric Research and Testing (CBRT), key laboratory of Complex Systems and Intelligence Science, {2. of Automation,{3., graduate school of the chinese Acad- emy of sciences, beijing 100080, china Center for Biometric Research and Testing (CBRT) Key Laboratory of Complex Systems and Intelligence Science Institute of Automation Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Beijing China

This paper introduces a fingerprint identification algorithm by clustering similarity with the view to overcome the dilemmas encountered in fingerprint identification. To decrease multi-spectrum noises in a fingerprint, we first use a dyadic scale space (DSS) method for image enhancement. The second step describes the relative features among minutiae by building a minutia-simplex which contains a pair of minutiae and their local associated ridge information, with its transformation-variant and invariant relative features applied for comprehensive similarity measurement and for parameter estimation respectively. The clustering method is employed to estimate the transformation space. Finally, multi-resolution technique is used to find an optimal transformation model for getting the maximal mutual information between the input and the template features. The experimental results including the performance evaluation by the 2.d International Verification Competition in 2.02.(FVC2.02., over the four fingerprint databases of FVC2.02.indicate that our method is promising in an automatic fingerprint identification system (AFIS).

关键词： dyadic scale space (DSS) minutia-simplex multi-resolution comprehensive similarity.

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Heterotrimeric G protein α subunit is involved in rice brassinosteroid response

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Cell Research 2006年第12期16卷 916-922页

作者： Lei Wang~(1,2. Yun-Yuan Xu~1 Qi-Bin Ma~(1,2. Dan Li~(1,2. Zhi-Hong Xu~(1,3. Kang Chong~(1,3. 1 {3. laboratory of Photosynthesis and Environmental Molecular Physiology,{2. of Botany,chinese academy of sciences,Nanxincun 2.,Xiangshan,beijing 100093.china,2.{13. school of the chinese Academv of sciences,{12. beijing,china 3.National Plant Gene Research Center (beijing),beijing 100093.china key laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Xiangshan China graduate school of the{2. Beijing China National Plant Gene Research Center (beijing) Beijing China

Heterotrimeric G proteins are known to function as messengers in numerous signal transduction *** nullmutation of RGA(rice heterotrimeric G protein α subunit),which encodes the α subunit of heterotrimeric G proteinin rice,causes severe dwarfism and reduced responsiveness to gibberellic acid in ***,less is known aboutheterotrimeric G protein in brassinosteroid(BR)signaling,one of the well-understood phytohormone *** thepresent study,we used root elongation inhibition assay,lamina inclination assay and coleoptile elongation analysis todemonstrated reduced sensitivity of dl mutant plants(caused by the null mutation of RGA)to 2.-epibrassinolide(2.-epiBL),which belongs to brassinosteroids and plays a wide variety of roles in plant growth and ***,RGA transcript level was decreased in 2.-epiBL-treated seedlings in a dose-dependent *** results show thatRGA is involved in rice brassinosteroid response,which may be beneficial to elucidate the molecular mechanisms of Gprotein signaling and provide a novel perspective to understand BR signaling in higher plants.

关键词： heterotrimeric G protein α subunit dl mutant BR signaling rice

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A preliminary study on fingerprinting approach in marine sediment dynamics with the rare earth elements

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Acta Oceanologica Sinica 2010年第4期29卷 62-77页

作者： ZHOU Xiaojing LI Anchun JIANG Fuqing MENG Qingyong key laboratory of Marine Geology ＆ Environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate school of the{2. Beijing 100039 China

Locating the quantitized natural sediment fingerprints is an important work for marine sediment dynamics *** total of 146 sediment samples were collected from the Shelf of the East china Sea and five rivers,including Huanghe （Yellow）,Changjiang （Yangtze）,Qiantang,Ou and Min *** sediment grain size and the contents of rare earth elements （REEs） were measured with laser particle size analyzer and ICP-MS *** results show that absolute REE content （ΣREE） and the concentration ratio of light REEs to heavy REEs （L/HREE） are different in the sediments among those *** are higher REE contents in being less than 2.m and 2.3. μm fractions in the Changjiang Estuary surface *** REE contents of bulk sediment are dominated by the corresponding values of those leading *** of sediment is higher close to the estuaries and declines seaward on the inner shelf of the East china Sea （ECS）.The L/HREE ratio has a tendency of increase southward from 2. ？ *** conditions plays a predominate role on spacial distributions of the surficial sediment’s REE *** some situations,the currents tend to remove the coarser light grains from initial populations,as well as the deposit of the finer heavy mineral *** other situations,the currents will change the ratio of sediment constituents,such as ratio between silts and clays in the *** a result,the various values of REE or L/HREE ratio in different bulk sediments are more affected by the change of size-fractions than source *** the long-term stable hydrodynamic environment,i.e.,the East china Sea Shelf,new sediment transport model based on the size and density gradation concept may help to understand the spatial distribution patterns of REE parameters.

关键词： rare earth elements fingerprints East china Sea Shelf sediment transport

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The diurnal variations, semiannual and winter anomalies of the ionospheric TEC based on GPS data in china

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Progress in Natural Science:Materials International 2005年第1期 57-61页

作者： HUO Xingliang 1,2.*, YUAN Yunbin 1, OU Jikun 1, WEN Debao 1,2.and LUO Xiaowen 1,2.1. {3. laboratory of {2. geodesy, institute of geodesy and geophysics, chinese academy of sciences, wuhan 4.0077, china 2. graduate {13. of chinese academy of sciences, beijing 10003., china) key laboratory of {2. {3.，institute of {3. and geophysics，chinese academy of sciences，wuhan 4.0077，{12. graduate school of{2.，{3. 10003.，china key laboratory of {2. {3.，institute of {3. and geophysics，chinese academy of sciences，wuhan 4.0077，{12.

With the spherical harmonic (SH) function model and the dual frequency GPS P code phase data from the Crustal Movement Observation Network of china (CMONOC) during the period from year 2.00 to 2.02. time series of total electron content (TEC) in the area of china is calculated. The diurnal variations, semiannual, and winter anomalies of the ionosphere in the area of china are analyzed and discussed, especially according to the results of year 2.01.

关键词： Global Positioning System spherical harmonic function model total electron content semiannual anomaly winter anomaly.

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Low-frequency fluctuations in the magnetosheath: Double Star TC-1 and Cluster observations

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Science china(Technological sciences) 2008年第10期51卷 1626-1638页

作者： DU Jian1,2.WANG Chi1, SONG Pu3.4 & ZHANG TieLong5 1 State key laboratory of Space Weather, Center for Space Science and Applied Research,{2., beijing 100190, china 2.graduate school,{2., beijing 10004., china 3.Earth, Environmental and Atmospheric sciences Department, University of Massachusetts, Lowell, Mas-sachusetts MA 01854, USA 4 Center for Atmospheric Research, University of Massachusetts, Lowell, Massachusetts MA 01854, USA 5 Space Research {13., Austrian {12. of sciences, Graz A-8010, Austria State key laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China graduate school Chinese Academy of Sciences Beijing China Earth Environmental and Atmospheric Sciences Department University of Massachusetts Lowell USA Center for Atmospheric Research University of Massachusetts Lowell USA Space Research institute Austrian Academy of Sciences Graz Austria

The magnetic field variations are analyzed in the range of time periods from 4 s to 2.0 s in the magnetosheath observed by the Double Star TC-1 and Cluster in 2.04. The characteristics of the magnetic field fluctuations are strongly controlled by the angle between the upstream interplanetary magnetic field (IMF) and the normal of the bow shock. Generally speaking, the magnetic field fluctuations in the quasi- parallel magnetosheath are more intense than those in the quasi-perpendicular ones. Almost purely compressional waves are found in the quasi-perpendicular magnetosheath. With the increase of the local plasma β, both the magnitude and direction of the magnetic field fluctuate more intensely. There exists an inverse correlation between the local temperature anisotropy T⊥/T|| and the plasma β.

关键词： low-frequency fluctuations magnetosheath MHD instabilities

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Response of Nematodes in a Hapli-Udic Argosol to Urea Amended with Urease and Nitrification Inhibitors

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Pedosphere 2006年第4期16卷 428-434页

作者： HUA Jian-Feng JIANG Yong LIANG Wen-Ju Soil Ecology laboratory Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China） graduate school of the{2. Beijing 100039 （China）

Effects of urea amended with urease and nitrification inhibitors on soil nematode communities were studied in a Hapli- Udic Argosol （Cambisol, FAO） in Liaoning Province of Northeast china. A completely random design with four treatments, i.e., conventional urea （CU）, slow-release urea amended with a liquid urease inhibitor （SRU1）, SRU1 ＋nitrification inhibitor dicyandiamide （SRU2., and SRU1 ＋ nitrification inhibitor 3.5-dimethylpyrazole （SRU3. and four replicates were applied. Thirty-nine genera of nematodes were identified, with Cephalobus and Aphelenchus being dominant; and in all treatments, the dominant trophic group was bacterivores. In addition, during the growth period of spring wheat （Triticum aestivum L.）, soil urease activity was lower in SRUs than in CU. The numbers of total nematodes and bacterivores at wheat heading and ripening stages, and omnivores-predators at ripening stage were higher in SUR3.than in CU, SRU1 and SRU2.（P 〈 0.05）.

关键词： Hapli-Udic Argosol nitrification inhibitor slow-release urea soil nematodes urease inhibitor

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Microcosmic analysis of ductile shearing zones of coal seams of brittle deformation domain in superficial lithosphere

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Science china Earth sciences 2004年第5期47卷 393-404页

作者： JU Yiwen1,2. WANG Guiliang2. JIANG Bo2.& HOU Quanlin1 1. {3. school,{2., beijing 10003., china 2. College of Mineral Resources and Geosciences, china University of Mining & Technology, Xuzhou 2.1008, china graduate school Chinese Academy of Sciences Beijing 100039 China College of Mineral Resources/Geosci. China University of Mining/Technol. Xuzhou 221008 China

The ductile shearing zones of coal seams in a brittle deformation domain in super-ficial lithosphere are put forward based on the study on bedding shearing and ductile rheology of coal seams. The macrocosmic and microcosmic characteristics include wrinkle fold, mymonitized zones and ductile planar structure of coal seams, etc., while the microcosmic characteristics may also include different optic-axis fabrics and the anisotropy of vitrinite reflectance as well as the change of chemical structure and organic geochemistry components. The forming mechanism is analyzed and the strain environment of ductile shearing zones of coal seams discussed. The result indicates that, in the superficial brittle deformation domain, the coal seams are easy to be deformed, resulting in not only brittle deformation but also ductile shearing deformation under the action of force. Because of simple shearing stress, the interlayer gliding or ductile rheology may take place between coal seams and wall rocks. Therefore, many ductile shearing zones come into being in superficial lithosphere (<5 km). The research on ductile shearing zone of brittle de-formation domain in superficial lithosphere is significant not only theoretically for the study of ductile shearing and ductile rheology of the lithosphere but also practically for the structural movement of coal seams, the formation and accumulation of coal-bed methane, and the preven-tion and harness of gas burst in coal mine.

关键词： brittle deformation domain, interlayer gliding, ductile rheology, ductile shearing zones of coal seams, coal mymonite, vitrinite reflectance anisotropy.

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New synthesis of amphiphilic copolymers PE-g-PEO via esterfication

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chinese Science Bulletin 2003年第6期48卷 523-525页

作者： L?Yingying1, MA Zhi1,2. HU Youliang1, XU G. X.3.& CHUNG T. C.3.1. State key laboratory of Engineering Plastics, Center for Molecular Science, {2. of Chemistry, chinese academy of sciences, Bei-jing beijing Lab of Catalysis, key Lab of Catalysis of china Na-tional Petroleum Corporation, beijing 100080, china 2. graduate school of chinese academy of sciences, beijing 10003., china 3. Department of Material Science and Engineering, Pennsylvania State University, University Park, PA 16802. USA State key laboratory of Engineering Plastics Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing beijing Lab of Catalysis Key Lab of Catalysis of China National Petroleum Corporation Beijing China graduate school of{2. Beijing China Department of Material Science and Engineering Pennsylvania State University University Park USA

A new series of high molecular weight amphi-philic graft copolymers PE-g-PEO has been prepared. The esterifications between PE-p-MS-g-MA and PEO with OH group at the chain end are carried out under different condi-tions. The compositions of these graft copolymers are studied by NMR and FTIR. It is found to be a convenient and effi-cient way to prepare high molecular weight PE-g-PEO graft copolymers.

关键词：聚乙烯聚(乙烯氧化物) 酯化反应合成方法亲油亲水两性片断共聚物 PE-g-PEO

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