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Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth Sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2, JIN Zhenmin1,3, QU Jing2 & WANG Lu2 1. state key laboratory of Geological Processes and Mineral Resources, china university of Geosciences, wuhan 430074, china 2. Graduate School of china university of Geosciences, wuhan 430074, china 3. Faculty of Earth Sciences, china university of Geosciences, wuhan 430074, china 1. state key laboratory of Geological Processes and Mineral Resources China University of Geosciences 430074 Wuhan China 2. Graduate School of china university of Geosciences 430074 Wuhan China 3. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of Chinese Continental Sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 300 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Arbuscular mycorrhizal for-mation of crucifer leaf mus-tard induced by flavonoids apigenin and daidzein

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Chinese Science Bulletin 2004年第12期49卷 1254-1261页

作者： DONG Changjin1,2 & ZHAO Bin1 1. state key laboratory of Agricultural Microbiology, Huazhong Agri- cultural university, wuhan 430070, china 2. Department of Biology, hubei Normal university, Huangshi 435002, china 1. state key laboratory of Agricultural Microbiology Huazhong Agricultural University 430070 Wuhan China 2. Department of Biology Hubei Normal University 435002 Huangshi China

Flavonoids from legume root secretion may probably act as signal molecules for expression of Rhizobial “nod” nodulation genes and AM fungal symbiotic gene. Leaf mustard is a non-mycorrhizal plant; it does not contain fla- vonoids and other signal molecules. AM fungi could not in- fect the roots of leaf mustard and form a symbiont in nature, when it was treated with flavonoids (apigenin or daidzein). The results of trypan blue staining showed that two kinds of AM fungi (G. intraradices and G. mosseae) successfully in- fected the roots of non-mycorrhizal plant leaf mustard. AM fungi grew towards and colonized the roots of leaf mustard, producing young spores and completing the course of life. AM fungi are the only one kind of fungi with ALP activity. The result of ALP staining has also proved that AM fungi infected successfully the roots of leaf mustard. AM fungi (G. intraradices and G. mosseae) that existed in the roots of non-mycorrhizal plant leaf mustard were probed by nested PCR and special molecular probes. The above-mentioned proof chains have fully proved that flavonoids induced AM fungi (G. intraradices and G. mosseae) to infect non-my- corrhizal plant and establish symbiotic relationship.

关键词：非菌根植物免疫十字花科叶芥菜芹甙元大豆黄酮类黄酮灌木菌根真菌嵌套PCR trypan蓝色染色

Wetland hydrologic application of satellite altimetry-A case study in the Poyang Lake watershed

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Progress in Natural Science:Materials International 2009年第12期19卷 1781-1787页

作者： Xiaobin Cai~(a,b),Wei Ji~(b,*) a state key laboratory of Information engineering in Surveying,Mapping and Remote Sensing,wuhan university,wuhan 430079,china b Department of Geosciences,university of Missouri,Kansas City,Kansas City,MO 64110,USA [a]state key laboratory of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China [b]Department of Geosciences University of Missouri Kansas City Kansas City MO 64110 USA

Hydrologic variation affects many functions of *** and accurately measuring hydrologic dynamics in a wetland watershed has become a fundamental need for estimating functional changes of *** satellite altimeters have become good data sources that can complement the measurements of gauge *** a case project applied in the Poyang Lake watershed,this study has developed a technical approach that integrates the altimeter measurements with the in situ water level *** derived water surface heights with Envisat RA-2 data are compared with the daily observations of in situ water *** average absolute observation difference between the"altimeter station"and its nearest gauge station is 0.307 m,which is comparable to the average differences among the gauge *** results suggest that the derived water surface heights from the altimeter data have a good accuracy,which can be used along with the in situ observations as supplements to fill the ungauged area in Poyang Lake wetlands.

关键词： Satellite altimetry Wetland hydrology Poyang Lake

Structure and Properties of Mg-doped SrBi_4Ti_4O_(15) Bi-layered Compounds

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Journal of wuhan university of Technology(Materials Science) 2008年第5期23卷 675-677页

作者：郝华 School of Materials Science and engineering Wuhan University of Technology state key laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

The structure and properties of Mg-doped SrBi4Ti4O15（SBT） were dicussed. Mg substitution into SBT had two possibilities states with the dopant amount variety. Mg cation substituted mostly into Sr^2＋ and the amount proportion was 68.11%.Mg ion will substitute into Ti ion site in perovskite layer when the doping amount increases. Polarization increases sharply when x=0.1 and then decreases becauses of the domain pinning. The Curie temperature of Mg-doped SBT is about 300 ℃ and there is a broad diffuse phase transition near Tc with a flat peak near the Ta of SBT.

关键词： Mg-doped bismuth layer structure ferroelectrics ferroelectric properties

3D thermo-hydro-mechanical-migratory coupling model and FEM analyses for dual-porosity medium

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Science china(Technological Sciences) 2010年第8期53卷 2172-2182页

作者： ZHANG YuJun 1&ZHANG WeiQing 2 1 state key laboratory of Geomechanics and Geotechnical engineering,Institute of Rock and Soil Mechanics, Chinese Academy of Sciences,wuhan 430071,china 2School of Civil engineering,Southwest Jiaotong university,Chengdu 610031,china 1. state key laboratory of Geomechanics and Geotechnical engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China2. School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

One kind of 3D coupled thermo-hydro-mechanical-migratory model for saturated-unsaturated dual-porosity medium was established,in which the stress field and the temperature field are single,but the seepage field and the concentration field are double,and the influences of sets,spaces,angles,continuity ratios,stiffness of fractures on the constitutive relationship of the medium can be *** relative three-dimensional program of finite element method was also *** comparing with the existing computation example,reliability of the model and the program were *** a hypothetical nuclear waste repository as a calculation example,the radioactive nuclide leak was simulated numerically with both the rock mass and the buffer being unsaturated media,and the temperatures,negative pore pressures,flow velocities,nuclide concentrations and normal stresses in the rock mass were *** results showed that the temperatures,negative pore pressures and nuclide concentrations in the buffer all present nonlinear changes and distributions that even though the saturation degree in porosity is only about 1/9 of that in fracture,the flow velocity of underground water in fracture is about 6 times of that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity,and that the regions of stress concentration occur at the vicinity of two sides of the boundary between buffer and disposal pit wall.

关键词： dual-porosity medium thermo-hydro-mechanical-migratory coupling three-dimensional model FEM analysis

Microstructure and shear strength of the brazed joint of Ti(C,N)-based cermet to steel

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Rare Metals 2010年第1期29卷 72-77页

作者： YE Dameng, XIONG Weihao, Zhang Xiuhai, QU Jun, and YAO Zhenghua state key laboratory of Plastic Forming Simulation and Die & Mould Technology, Huazhong university of Science and Technology, wuhan 430074, china state key laboratory of Plastic Forming Simulation and Die & Mould Technology Huazhong University of Science and Technology

Firm joins were obtained between Ti（C,N）-based cermet and steel with Ag-Cu-Zn-Ni filler metal by vacuum brazing. The effects of technological parameters such as brazing temperature, holding time, and filler thickness on the shear strength of the joints were investigated. The microstructure of welded area and the reaction products of the filler metal were examined by scanning electron microscopy （SEM）, metallographic microscope （OM）, energy-dispersive X-ray analysis （EDS）, and X-ray diffraction （XRD）. The brazing temperature of 870℃, holding time of 15 min, and filler thickness of 0.4 mm are a set of optimum technological parameters, under which the maximum shear strength of the joints, 176.5 MPa, is achieved. The results of microstructure show that the wettability of the filler metal on Ti（C,N）-based cermet and steel is well. A mutual solution layer and a diffusion layer exist between the welding base materials and the filler metal.

关键词： Ti(C,N)-based cermet vacuum brazing filler metal shear strength interface structure

A Network-Based VPN Architecture Using Virtual Routing

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wuhan university Journal of Natural Sciences 2005年第1期10卷 161-164页

作者： ZHANG Bao-liang 1,2,HU Han-ping 1,2,WU Xiao-gang 1,2, KONG Tao 31.state Education Ministry key laboratory of Image Information and Intelligent Control, wuhan 430074, hubei, china 2.Institute of Pattem Recognition and Artificial Intelligonce, Huazhong university of Science and Technology, wuhan 430074, hubei, china 3.709th Research Institute of china Shipbuilding engineering Society, wuhan 430074, hubei, china state Education Ministry key Laboratory of Image Information and Intelligent Control Wuhan China Huazhong university of Science and Technology Institute of Pattern Recognition and Artificial Intelligonce Wuhan China (GRID:grid.33199.31) (ISNI:***) state Education Ministry key Laboratory of Image Information and Intelligent Control Wuhan China (GRID:grid.33199.31) Huazhong university of Science and Technology Institute of Pattern Recognition and Artificial Intelligonce Wuhan China (GRID:grid.33199.31) (ISNI:***) 709th Research Institute of china Shipbuilding engineering Society Wuhan China (GRID:grid.33199.31)

A network-based Virtual Private Network (VPN) architecture by using fundamental routing mechanism is proposed. This network is a virtual overlay network based on the relay of IP-in-IP tunneling of virtual routing modules. The packet format employs the encapsulation of IPSec ESP(Encapsulating Security Payload), an impact path code and an extended DS(Differentiated Services) code to support multi-path routing and QoS. Comparing with other models of VPN, this network system can be deployed in the current network with little investment, and it is easy to implement. The simulation result shows its performance is better than the traditional VPN system of black box mode.

关键词： virtual routing network-based VPN proactive defense

Microstructure and Properties of W-15Cu Alloys Prepared by Mechanical Alloying and Spark Plasma Sintering Process

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Journal of wuhan university of Technology(Materials Science) 2008年第3期23卷 399-402页

作者：章桥新 School of Mechanical and Electronic engineering Wuhan University of Technology state key laboratory of Advanced Technology for Materials Synthesis&Processing Wuhan University of TechnologyWuhan 430070China

W-15Cu composite powders prepared by mechanical alloying （MA） of raw powders were consolidated by spark plasma sintering （SPS） process at temperature ranged 1 230-1 300 ℃ for 10 min and under a pressure of 30 MPa. By using high energy milling, particles containing very fine tungsten grains embedded in copper, called composite particles, could be produced. The W grains were homogeneously dispersed in copper phase, which was very important to obtain W-Cu alloy with high mechanical properties, fine and homogeneous microstructure. The microstructure and properties of W-15Cu alloys prepared by SPS processes at different temperature were researched. The results show that W-15Cu alloys consolidated by SPS can reach 99.6 % relative density, and transverse rupture strength （TRS） is 1 400.9 MPa, Rockwell C hardness （HRC） is 45.2, the thermal conductivity is 196 W/m-K at room temperature, the average grain size is less than 2 μm, and W-15Cu alloy with excellent properties, homogeneous and fine microstructure is obtained.

关键词： W-15Cu mechanical alloying spark plasma sintering (SPS)

A METHOD TO APPROACH OPTIMAL RESTORATION IN IMAGE RESTORATION PROBLEMS WITHOUT NOISE ENERGY INFORMATION

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Acta Mathematica Scientia 2003年第4期23卷 512-520页

作者：曾三友丁立新康立山 state key laboratory of software engineering Wuhan University Wuhan 430072 China Deptartment of Computer Science Zhuzhou Institute of Technology Zhuzhou 402008 China state key laboratory of software engineering Wuhan University Wuhan 430072 China

This paper proposes a new image restoration technique, in which the resulting regularized image approximates the optimal solution steadily. The affect of the regular-ization operator and parameter on the lower band and upper band energy of the residue of the regularized image is theoretically analyzed by employing wavelet transform. This paper shows that regularization operator should generally be lowstop and highpass. So this paper chooses a lowstop and highpass operator as regularization operator, and construct an optimization model which minimizes the mean squares residue of regularized solution to determine regularization parameter. Although the model is random, on the condition of this paper, it can be solved and yields regularization parameter and regularized solution. Otherwise, the technique has a mechanism to predict noise energy. So, without noise information, it can also work and yield good restoration results.

关键词： Regularization method image restoration wavelet transform