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吉林大学学报(地球科学版) 2015年第S1期 280-280页

作者： Sun He Xiao Yilin CAS Key laboratory of Crust-Mantle materials and Environments School of Earth and Space Sciences University of Science and Technology of China

The Raobazhai ultramafic massif,which exposed in the north Dabie,is thought to be a segment of subcontinental lithospheric mantle that was subducted and exhumed during the Triassic *** on these ultramafic rocks can provides intriguing information on geodynamic processes and material fluxes between mantle and crust during continent-continent collision,including the stages of subduction and *** this study we investigate in detail the Raobazhai garnet *** the basis of textural relations and

关键词： collision continent mantle garnet subduction crust intriguing Eastern Triassic north

Deformation and 40Ar/3.Ar thermochronology on the mylonites from south Tan-Lu fault:The geological significance

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Deformation and 40Ar/39Ar thermochronology on the mylonites ...

第九届全国固体核径迹学术研讨会

作者： X.Y.YANG~(1,2) 1.CAS Key laboratory of Crust-Mantle materials and Environments,school of {3. and space sciences,university science and technology of China,hefei 23.026,China 2.CAS Key laboratory of Isotope Geochronology and Geochemistry,Guangzhou Institute of Geochemistry,Guangzhou,510640,China

Tan-Lu fault belt is an important deep fault belt in east China and Asian continent,and its southern part is the key part for geology,where the series of mylonites were developed in the ductile shear zones since its shifting *** plastic deformation is commonly occurring in the *** deformed biotite and feldspar may record the chronological information since the period of deformation,the age from the deformed minerals may represent the important period of the history of deformation and even the shifting movement of the fault *** and plagioclase samples separated from the mylonite samples were determined by 40Ar/3.Ar fast neutron activation *** the basis of the deformed minerals with microscope and TEM observation,the stop-heating technique is hired here for determination of Ar/Ar *** ages from single minerals were obtained with the plateau ages of and isoclines ages of 98.49± 0.3.Ma-113.89±0.3.Ma and 98.80±0.19Ma-113.99±0.27Ma,*** two types of Ar/Ar thermochronology ages are well consistent,so that the convinced deformed ages are supposed to be 98Ma-114 *** 40Ar/3.Ar thermochronology ages may represent the cooling ages of the shifting movement of Tan-Lu fault belt.

关键词： ductile shear zones plastic deformation mlonites 40Ar/3.Ardating Tan-Lu fault belt

Transverse instability and magnetic structures associated with electron phase space holes

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Transverse instability and magnetic structures associated wi...

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Aimin Du,~1 Mingyu Wu,~2 Quanming Lu,~(2,a)) Can Huang,~2 and Shui Wang~2 1 Institute of Geology and Geophysics,Chinese Academy of sciences,Beijing 100029,China 2 CAS Key laboratory of Basic Plasma Physics,school of {3. and space sciences, university of science and technology of China,hefei,Anhui 23.026,China

Electron phase space holes(electron holes) are found to be unstable to the transverse instability. Two-dimensional(2D) electromagnetic particle-in-cell simulations are performed to investigate the structures of the fluctuating magnetic field associated with electron *** combined actions between the transverse instability and the stabilization by the background magnetic field (B=Be) lead a one-dimensional electron hole into several 2D electron holes which are isolated in both the x and y *** electrons trapped in these 2D electron holes suffer the electric field drift v=E×B/B due to the existence of the perpendicular electric field E,which generates the current along the z ***,the unipolar and bipolar stmctures are formed for the parallel cut of the fluctuating magnetic field along the x and y directions,*** the same time,these 2D electron holes move along the x direction,and the unipolar structures are formed for the parallel cut of the fluctuating magnetic field along the z direction.

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A Simulator for Producing of High Flux Atomic Oxygen Beam by Using ECR Plasma Source

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Journal of materials science & technology 2004年第6期20卷 759-762页

作者： Shuwang DUO, Meishuan LI and Yaming ZHANGShenyang National laboratory for materials science, Institute of Metal Research, Chinese Academy of {3., Shenyang 110016, China Shenyang Natl. Lab. for Mat. Sci. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

In order to study the atomic oxygen corrosion of spacecraft materials in low earth orbit environment, an atomic oxygen simulator was established. In the simulator, a 2.45 GHz microwave source with maximum power of 600 W was launched into the circular cavity to generate ECR (electron cyclotron resonance) plasma. The oxygen ion beam moved onto a negatively biased Mo plate under the condition of symmetry magnetic mirror field confine, then was neutralized and reflected to form oxygen atom beam. The properties of plasma density, electron temperature, plasma space potential and ion incident energy were characterized. The atomic oxygen beam flux was calibrated by measuring the mass loss rate of Kapton during the atomic oxygen exposure. The test results show that the atomic oxygen beam with flux of 1016-1017 atoms-cm-2·s-1 and energy of 5-3. eV and a cross section of φ80 mm could be obtained under the operating pressure of 10-1-10-3.Pa. Such a high flux source can provide accelerated simulation tests of materials and coatings for space applications.

关键词： Atomic oxygen Low earth orbit space environment ECR plasma Microwave

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安庆黄大湖防洪与减灾的对策分析

水土保持学报 2003年第6期17卷 106-109页

作者：王心源胡玮周迎秋朱同林孙叶根鲁传响安徽师范大学国土资源与旅游学院遥感实验室池州师范专科学校资源与环境科学系安徽池州247100

自20世纪90年代以来黄大湖区水灾不断。与50年代相比,雨情偏大、水情恶化、灾情放大。究其原因是由于黄大湖蓄洪调洪功能的脆弱性。采用遥感图像和相关资料数据研究黄大湖的地质历史、气候、水文和地形特征,分析黄大湖的水域动态变化和... 详细信息

自20世纪90年代以来黄大湖区水灾不断。与50年代相比,雨情偏大、水情恶化、灾情放大。究其原因是由于黄大湖蓄洪调洪功能的脆弱性。采用遥感图像和相关资料数据研究黄大湖的地质历史、气候、水文和地形特征,分析黄大湖的水域动态变化和主要存在问题,指出泥沙淤积和围湖造田是湖域萎缩的主要原因。针对这一症结,讨论了减少水灾的对策和措施:(1)加强江湖关系研究,完善湖区防洪水利建设规划;(2)充分发挥与龙感湖、泊湖的相通优势;(3.建立水情自动预报系统;(4)正确处理蓄洪与建设、河道疏浚以及河道行洪能力关系。从发展渔业和旅游业使湖区的生态环境和资源利用得到最优化的利用角度,探讨了黄大湖的经济效益。

关键词：蓄洪调洪防洪减灾可持续发展安庆黄大湖

Urban effects and summer thunderstorms in a tropical cyclone affected situation over Guangzhou city

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science China earth sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3.YAN JingHua1 & HU HaiBo2 1 Institute of Tropical and Marine Meteorology,Chinese Meteorological Administration(CMA),Guangzhou 510080,China 2 Institute of Urban Meteorology,CMA,Beijing 100089,China 3.State Key laboratory of Severe Weather,Chinese Academy of Meteorological sciences,Beijing 100081,China Institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou China State Key laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing China Institute of Urban Meteorology CMA Beijing China

With data mainly from Guangzhou mesonet Automatic Weather Stations(AWS),Guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4 August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over Guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

3.D MHD Simulation of the Evolution of Two CME Events Using Magnetized Plasma Blob Model

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3-D MHD Simulation of the Evolution of Two CME Events Using ...

第十四届全国日地空间物理学术研讨会

作者： F. Shen1 X. S. Feng1 Yuming Wang2 S. T. Wu3.W. B. Song1 J. P. Guo1 and Y. F. Zhou1 (1 State Key laboratory of space Weather, National space {3. Center, CAS, Beijing 100190, China) (2 school of earth & space sciences, university of {3. & technology of China, hefei, Anhui 23.026, China) (3.Center for space Plasma and Aeronomic Research, the university of Alabama in Huntsville, Huntsville, AL 3.899 USA)

A three-dimensional （3.） time-dependent, numerical magnetohydrodynamic （MHD） model is used to investigate the evolution and interaction of two CMEs in the nonhomogeneous ambient solar wind. The background solar wind is constructed based on the self-consistent source surface with observed line-of-sight of magnetic field and density from the source surface of 2.5 Rs to the earth’s orbit （215 Rs） and beyond. The CMEs are simulated by means of a very simple flux rope model: a high-density, -velocity and -temperature magnetized plasma blob is superimposed on a steady state background solar wind with an initial launch direction. The dynamical interaction of a CME with the background solar wind flow between 2.5 and 220 Rs is investigated. We have chosen two well-defined CME events as the test cases. （1） the halo-CME event of 4-6 April 2000;（2） the two successive CMEs occurring on 2001 March 28 and forming a multiple magnetic cloud （multi-MC） in interplanetary space. In this validation study we find that this 3. MHD model, with the asynchronous and parallel time-marching method, the self-consistent source surface as initial-boundary conditions and the simple flux rope as CME model, provide a relatively satisfactory comparison with the ACE spacecraft observations at the L1 point, and can also reproduce and explain some of the general characters of the multiple magnetic clouds observed by satellite. Then, in order to understand the physical processes of the acceleration and deceleration of the CME propagation in the heliosphere, we also analyze the forces which caused the acceleration and deceleration in detail.

关键词：

Effect of Cooling Rate on the Microstructure of ZA48 Alloy

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Journal of Wuhan university of technology(materials {3.) 2010年第5期25卷 811-813页

作者：王杰芳谢敬佩 school of Physics and Engineering The Key Laboratory of Material Physics of the Ministry of Education of China Zhengzhou University The College of materials science & Engineering Henan University of Science and Technology

The effect of cooling rate on the microstructure of ZA48 alloy was investigated. The alloy was prepared using a relatively simple technique, i e, rapid cooling of the melt in a steel wedge mould. The dependence of microstructure on the cooling rate （about 40 to 10^3.K/s） was determined by the secondary dendrite arm space size measurement, optical microscopy（OM）, and transmission electron microscopy （TEM）. It is found that the matrix structure over a large cooling rate is composed of α-Al dendrite and eutectoid （α＋η）, the size of α-Al dendrite decreases with increasing cooling rate. The relationship between the cooling rate and the secondary dendrite arm space size has been established. TEM shows that a large number of small and dispersed precipitations can be seen in the primary α phase of tip region. Electron diffraction pattern shows that the precipitate phase is Zn3.g2 phase.

关键词： cooling rate microstructure secondary dendrite arm space size precipitation

Block modeling and segmentally iterative ray tracing in complex 3. media

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Block modeling and segmentally iterative ray tracing in comp...

中国科学院地质与地球物理研究所2006学术年会

作者： Tao Xu~1,Guoming Xu~2,Ergen Gao~2,Yingchun Li~2,Xianyi Jiang~3.and Kaiyun Luo~3.1 Chinese Academy of sciences,Institute of Geology and Geophysics,State Key laboratory of Lithosphere Evolution,No.19,Beituchengxi Road,Chaoyang District,Beijing 100029,China. 2 university of {3. and technology of China,school of earth and space sciences,no.96,Jinzhai Road, Anhui Province,Heifei 23.026,China. 3.Bureau of Geophysical Prospecting,Geophysical Research Institute,CNPC,Zhuozhou,Hebei,China.

We propose using a set of blocks to approximate geologically complex media that cannot be well described by layered *** between blocks are triangulated to prevent overlaps or gaps often produced by other techniques,such as B-splines,and to speed up the calculation of intersection points between a ray and block *** also use a smoothing algorithm to make the normal vector of each triangle continuous at the boundary,so that ray tracing can be performed with stability and *** on Fermat’s principle,we perturb an initial raypath between two points,generally obtained by shooting,with a segmentally iterative ray-tracing(SIRT) *** points on a ray are updated in sequence,instead of simultaneously,because the number of new intersection points may be increased or decreased during the iteration *** improve convergence speed,we update the intersection points by a first-order explicit formula instead of traditional iterative *** transmitted and reflected waves are *** tests demonstrate that the combination of block modeling and segmentally iterative ray tracing is effective in implementing kinematic two-point ray tracing in complex 3. media.

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First principles study on effect of lanthanum on nitrogen diffusion in ε-Fe_3. phase

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Rare Metals 2007年第S1期26卷 251-254页

作者： WU Yeqiong,and YAN Mufu school of materials science and Engineering,Harbin Institute of {3.,Harbin 150001,China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

The effect of lanthanum(La) on nitrogen atom diffusion in ε-Fe3. phase produced during nitriding with and without rare earth addition were studied based on the density function theory of first principles and the quantum mechanics program CASTEP code of material Studio *** results show that the presence of La in ε-Fe3. phase can lead to the shrinks of a and b axis and the elongation of c axis of ε-Fe3. crystal *** total energy and the stability of the crystal cell with La are lower and higher than that without La,*** activation energy of nitrogen atom in ε-Fe3. phase with La is 1.01 eV smaller than that in ε-Fe3. phase without *** is the main reason why rare earth elements diffusing into compound layer produced during nitriding can accelerate the nitriding process or shorten the nitriding duration.

关键词： first principles lanthanum nitrogen diffusion ε-Fe_3. phase