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Sm-Nd and zircon SHRIMP U-Pb dating of Huilanshan mafic granulite in the Dabie Mountains and its zircon trace element geochemistry

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Science china Earth Sciences 2005年第12期48卷 2081-2091页

作者： HOU Zhenhui1, LI Shuguang1, CHEN Nengsong2. LI Qiuli1 & LIU Xiaoming3 1. School of Earth and Space Sciences, university of Science and Technology of{2., Hefei 2.002.,{2. 2. The Key Laboratory of Continental Dynamics of the Ministry of Education, Northwest university, Xi’an 710069,{2. 3. Faculty of Earth Sciences, china university of geosciences, wuhan 430074,{2. 1. School of Earth and Space Sciences University of Science and Technology of China 230026 Hefei China 2. The Key Laboratory of Continental Dynamics of the Ministry of Education Northwest University 710069 Xi’an China 3. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

The mafic granulites from Huilanshan are outcropped on the center of the Luotian dome in the northern Dabie Mountains. The Sm-Nd isochron defined by granulite-facies meta-morphic minerals (garnet + clinopyroxene + hypersthene) yields an age of 136 ± 18 Ma indicating the early Cretaceous granulite-facies metamorphism. The cathodoluminescence (CL) images of zircons from the granulite show clearly core-mantle-rim structures. The zircon cores are charac-terized by typical oscillatory zoning and highly HREE enriched patterns, which suggests their magma origin. Some zircon cores among them with little Pb loss give SHRIMP U-Pb ages rang-ing from 753 to 780 Ma, which suggests that the protolith of Huilanshan granulite is Neopro-terozoic mafic rocks. The zircon mantles usually cut across the oscillatory zone of the zircon cores have 3―10 times lower REE, Th, U, Y, Nb and Ta contents than the igneous zircon cores but have high common Pb contents. These characteristics suggest that they were formed by hydrothermal alteration of the igneous zircons. The part of zircon mantles with little Pb loss give a similar SHRIMP U-Pb age (716―780 Ma) to the igneous zircon cores, which implies that the hydrothermal events occurred closely to the magmatic emplacement. In view of the strong early Cretaceous magmatism in the Luotian dome, consequently, the Huilanshan mafic granulite was formed by heating of the Neoproterozoic mafic rocks in mid-low crust, which caused the granu-lite-facies metamorphism underneath the Dabie Mountains. The similarity between the granulite metamorphic age (136 ± 18 Ma) defined by Sm-Nd isochron and K-Ar age of 12.―12. Ma given by amphible from the gneiss in Luotian dome suggests a rapid uplifting of the Luotian dome, which may result in further exhumation of the ultrahigh pressure metamorphic rocks in the Dabie Mountains.

关键词： Dabie orogen, granulite, zircon U-Pb ages, Sm-Nd age.

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Preparation and ferroelectric properties of Bi_(3.4)Ce_(0.6)Ti_3O_(12. thin films grown by sol-gel method

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Science china(Technological Sciences) 2008年第1期51卷 10-15页

作者： GUO DongYun1, LI MeiYa1, LIU Jun1, YU BenFang1, PEI Ling1, WANG YunBo2. YU Jun2.& YANG Bin2.1 Department of Physics, wuhan {2., wuhan 430072. china 2.Department of Electronic Science and Technology, Huazhong {2. of Science and Technology, wuhan 430074, china Department of Physics Wuhan UniversityWuhan 430072China

We have investigated the preparation and properties of Bi3.4Ce0.6Ti3O12.thin films. The Bi3.4Ce0.6Ti3O12.thin films were fabricated on the Pt/Ti/SiO2.Si substrates using sol-gel method. The structure and morphology of the films were characterized us- ing X-ray diffraction and atomic force microscopy. The thin films showed a perovskite phase and dense microstructure. The dielectric constant and the dissi- pation factor of the Bi3.4Ce0.6Ti3O12.thin films were about 172.and 0.031 at 1 kHz, respectively. The 2.r and 2.c of the Bi3.4Ce0.6Ti3O12.thin films were 67.1 μC/cm2.and 2.9.7 kV/cm, respectively, under an applied field of 600 kV/cm. The Bi3.4Ce0.6Ti3O12.film did not show fatigue up to 4.46×109 switching cycles at a frequency of 1 MHz, and showed good insulating behavior according to the test of leakage current.

关键词： Bi3.4Ce0.6Ti3O12 thin film sol-gel method ferroelectric property dielectric fatigue leakage current

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The Simulating of the Woven Fabric Visual System

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武汉理工大学学报 2006年第S3期28卷 999-1002页

作者： DENG Zhongmin LU Hongmei~2.ZHU Lili~2.(1.Huazhong university of Science & Technolog,wuhan {2.,china, 2.wuhan university of Science & Engineering,Wnhan 430073,china) Huazhong university of Science &Technolog Wuhan 430074China wuhan university of Science & Engineer{2. Wuhan 430073China

With Visual C++6.0 as the language,following the traditional waterfall model and the software engineering theory,utilizing the technique of the dialog box,picture synthesis in VC,the writers present the developing of the woven fabric CAD system under the environment of *** system includes weave designing,yarn simulating,color matching,han- dling hand sample fabric and the testing effect. The basic methods and effect evaluation have been discussed and developed for the weave designing,yarn appearance simulat- ing and fabric color matching,as well as handling hand sample states the image processing,such as DIB(Device-independent bitmap);meanwhile,the developed system has been tested and run in actual design and textile mill *** operated results show that the system runs steadily,efficiently and smart,it can be widely used in yarn and fabric design by using with the merits of convenience,celerity and nicety in shortening the developing periods of product;additionally,it provides in fact a new ap- proach to technical design for textile mills.

关键词： fabric simulating visual system

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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science china(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2. HUANG GuanHua1,2.& QU ZhongYi3 1 center for Agriculture Water Research, china Agricultural {2., Beijing 100083, china 2.Chinese-Israeli International center for Research and Training in Agriculture, china Agricultural {2., Beijing 100083, china 3 Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural {2., Hohhot 010018, china 1. center for Agriculture Water Research China Agricultural University Beijing 100083 China 2. Chinese-Israeli International center for Research and Training in Agriculture China Agricultural University Beijing 100083 China 3. Water Conservancy and Civil Engineering College Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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Ferroelectric properties of Bi_(3.2.)La_(0.75)Ti_(3)O_(12. thin films prepared by sol-gel method

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Science china(Technological Sciences) 2007年第1期50卷 1-6页

作者： GUO DongYun1, LI MeiYa1, PEI Ling1, YU BenFang1, WU GengZhu1, ZHAO XingZhong1, WANG YunBo2.& YU Jun2.1 Department of Physics, {2. university, {2. 430072. china 2.Department of Electronic Science and Technology, Huazhong university of Science and Technology, wuhan 430074, china 1. Department of Physics Wuhan University Wuhan 430072 China 2. Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

The Bi3.2.La0.75Ti3O12.thin films were fabricated on the Pt/Ti/SiO2.Si substrates using sol-gel method. The structure and morphology of the films were characterized us-ing X-ray diffraction and atomic force microscopy. The thin films showed a perov- skite phase and dense microstructure. The 2.r and 2.c of the Bi3.2.La0.75Ti3O12.thin films annealed at 700℃ were 18.6 μC/cm2.and 4.1 V, respectively, under an applied voltage 10 V. After the switching of 1×1010 cycles, the Pr value decreased to 90% of its pre-fatigue values. The films showed good insulating behavior according to the test of leakage current. The dielectric constant and the dissipation factor of the Bi3.2.La0.75Ti3O12.thin films were about 176 and 0.046 at 1 kHz, respectively.

关键词： Bi3.2.La0.75Ti3O12 thin film sol-gel method ferroelectric properties fatigue leakage current

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Study on the two and three-parameter working stability regions of 3Y-TZP suspension

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Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2. ZHANG Xinni3, CHEN Sha’ou3 & QI Ping3 1. Department of Chemistry, Qingdao {2., Qingdao 2.6071, china 2. Department of Chemistry, Tsinghua {2., Beijing 100084, china 3. Department of Physics, Qingdao {2., Qingdao 2.6071, china 1. Department of Chemistry Qingdao University Qingdao 266071 China 2. Department of Chemistry Tsinghua University Beijing 100084 China 3. Department of Physics Qingdao University Qingdao 266071 China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3Y-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3Y-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3Y-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3Y-TZP, suspension, stability, DLVO theory, interparticle potential energy.

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Charge order and spin order in Nd_(0.5)Sr_(0.5)Mn_(1-x)(Ga_x, Ti_x)O_3 system

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 294-302页

作者： REN QingBao1,2. ZHU WeiTing1, HONG Bo2.& ZHANG YuHeng2.1 Department of Physics, Lishui {2., Lishui 32.000, china 2.National High Magnetic Field Laboratory, {2. of Science and Technology of china, Hefei 2.002., china 1. Department of Physics Lishui University Lishui 323000 China 2. National High Magnetic Field Laboratory University of Science and Technology of China Hefei 230026 China

Magnetic properties of Nd_(0.5)Sr_(0.5)Mn_(1-x)(Ga_x, Ti_x)O_3 system (0.04≤x≤0.4) were inves- tigated through magnetization and electron spin resonance (ESR) measurements. It was observed that a small amount of Ti substitution for Mn will destroy the charge-ordering (CO) phase completely and induce the cluster-spin-glass phase in the system, which displays a procedure of collapse of CO and of an enhancement of spin ordering (SO) phase. In contrast, the Ga substitution for Mn induces a melt- ing of CO phase in the system. It was observed that with substitution the CO phase is suppressed gradually and the remanent CO phase is retained all the while, and withal, there is a co-existence of AFM CO phase and FM SO at low temperature. In addition, an abrupt rise of magnetization was observed in M-T curves. We attributed this abnormal phenomenon to a transition from canted AFM SO to FM SO in CO region.

关键词： charge ordering spin ordering antiferromagnetic transition

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Disequilibria between ^(2.0)Po and ^(2.0)Pb in surface waters of the southern South china Sea and their implications

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Science china Earth Sciences 2006年第1期49卷 103-112页

作者： YANG Weifeng, HUANG Yipu1,2. CHEN Min1,2. ZHANG Lei, LI Hongbin, LIU Guangshan1,2.& QIU Yusheng1,2.1. Department of Oceanography, Xiamen university, Xiamen 361005, china 2. State Key Laboratory of Marine Environmental Science, Xiamen university, Xiamen 361005, china 1. Department of Oceanography Xiamen University Xiamen 361005 China 2. State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

Activities of the naturally occurring radionuclides, ^(2.0)Pb and ^(2.0)Po,were measured in both dissolved ( 0.45 μm) phases from surfacewaters of the southern South china Sea. The average activity of particulate ^(2.0)Pb, 0.2. Bq/m^3 (n= 2.), accounted for about 12. of the total ^(2.0)Pb, which corresponds with values of open *** ^(2.0)Po, with an average activity of 0.43 Bq/m^3, accounted for about 40% of the total^(2.0)Po, which was much higher than those of open and eutrophic oceans. The residence times oftotal ^(2.0)Po and ^(2.0)Pb in surface waters estimated from an irreversible steady-state model were0.82.a and 1.16 a, respectively. The consistently high fractionation factor calculated either byscavenging rate constants (5.42. or K_d values (6.69) suggested that a significant fractionationoccurred between ^(2.0)Po and ^(2.0)Pb during their removal from solution to particles and that thetwo radionuclides had different biogeochemical cycling pathways in the oligotrophic South china ***, our results indicated that there exist different fractionation mechanisms between^(2.0)Po and ^(2.0)Pb in different marine environments: in eutrophic ocean, plankton detritus andfecal pellets are the main carrier of ^(2.0)Po and ^(2.0)Pb, by which ^(2.0)Po and ^(2.0)Pb havebeen scavenged and removed; while in oligotrophic ocean, microbes could become the main carrier of^(2.0)Po and fractionate ^(2.0)Po and ^(2.0)Pb significantly as a result of scarce plankton detritusand fecal pellets. These results suggest the use of ^(2.0)Po to trace marine biogeochemicalprocesses relating to microbial activities and the cycling of sulfur group elements (S, Se, Te andPo).

关键词： South china Sea, 2.0Po, 2.0Pb, disequilibria, scavenging.

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Muddy water seepage theory and its application

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Science china(Technological Sciences) 2006年第4期49卷 476-484页

作者： DANG Faning1, LIU Yunhe1, CHEN Junqiang1, ZHENG Zhongan2.& WANG Zhouyu2.1. Institute of Water Resources and Hydro-electric Engineering, Xi’an {2. of Technology, Xi’an 710048, china 2. City Water Matter Bureau, Shizuishan 753000, china 1. Institute of Water Resources and Hydro-electric Engineering Xi’an University of Technology Xi’an 710048 China 2. City Water Matter Bureau Shizuishan 753000 China

On condition that the seepage coefficients of sediment and stratum are nar- rowly or widely different, seepage stratum is homogeneous or layer. The muddy water seepage integral and differential equations based on Darcy’s law are established, and then their difference formula of the differential equations are derived. The method pre- sented was used in the deep recharge test in Shizuishan, where power plant cooling tail- ing water was used to recharge and mine deep underground water. This is firstly used in{2.. The law of sediment accumulation on the earth surface, and the rule of infiltration capacity changing with time are studied. The pattern of water table changing with time affected by the recharge irrigation is predicted.

关键词： seepage, sediment accumulation, seepage coefficient, muddy water seepage differential equation.

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Cycladophora davisiana(Radiolarian)in the Bering Sea during the late Quaternary:A stratigraphic tool and proxy of the glacial Subarctic Pacific Intermediate Water

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Science china Earth Sciences 2005年第10期48卷 1698-1707页

作者： WANG Rujian1 & CHEN Ronghua2.1. State Key Laboratory of Marine Geology, Tongji university, Shanghai 2.0092. china 2. The Key Laboratory of Submarine Geoscience, State Oceanic Administration, Hangzhou 310012. china State Key Laboratory of Marine Geology Tongji university Shanghai china The Key Laboratory of Submarine Geoscience State Oceanic Administration Hangzhou china

Cycladophora davisiana (Radiolarian) contents are counted in two cores of the Ber-ing Sea and correlated well with the oxygen isotopic records of ice in the deep core obtained by the Greenland Ice Sheet Project II (GISP 2. and deep-sea sediments (SPECMAP) of the world oceans. Millennial scale climatic events, for example, Younge Dryas and B?lling/Aller?d events, Heinrich1 and Dansgaard-Oeschger1events, recorded by C. davisiana percents are distin-guished from Core B4-2. C. davisiana events b, c1, c2. d, e1 and e2. respectively, corresponding to oxygen isotopic 2.0, 3.1, 3.3, 4.0, 5.1 and 5.3, are identified from Core B2.9. High resolution re-cords of C. davisian are tuned to the oxygen isotopic records in GISP 2.and SPECMAP and the depth-age frameworks are established in the two cores, supplying a stratigraphic base for future paleoceanographic and paleoclimatic studies. High C. davisiana during the glacial periods in the two cores indicate that they can serve as a proxy of the glacial Subarctic Pacific Intermediate Water, which verifies the glacial Subarctic Pacific Intermediate Water brought from the Bering Sea.

关键词： Cycladophora davisiana, stratigraphic tool, YD and B/A events, Heinrich 1 and D/O1 events, proxy of glacial Subarctic Pacific Intermediate Water, late Quaternary, Bering Sea.

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