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Research on Secure Authentication Mechanism of Grid

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Journal of Donghua University(eng.ish Edition) 2005年第4期22卷 94-97页

作者：张龙军陈克非赵怀勋 dept. of computer sci. and eng. Shanghai Jiaotong University Shanghai 200030 dept. of Communicate eng. Eng. College of Armed Police Force Xi'an 710086

Based on the analysis on the security mechanism of grid, this paper discusses the advantages of latest techniques of grid security, and presents a secure authentication scheme of grid based on elliptic curve cryptosys... 详细信息

关键词： Grid GT3 ECC.

The Application of SCC-DV-X_a Computational Method of Quantum Chemistry in Cement Chemistry

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Journal of Wuhan University of Technology(Materials sci.nce) 2001年第3期16卷 6-11页

作者：王志 dept. of Materials sci. and eng. Jinan University Shandong 250022 China

It has been explored why quantum chemistry is applied to the research field of cement chemistry. The fundamental theory of SCC-DV-Xα computational method of quantum chemistry is synopsized. The results obtained by computational quantum chemistry method in recent years of valence-bond structures and hydration activity of some cement clinker minerals, mechanical streng.h and stabilization, of some hydrates are summarized and evaluated. Finally the prospects of the future application of quantum chemistry to cement chemistry are depicted.

关键词： quantum chemistry cement calculated results hydratian property

Applied Strain Field on Microstructure Optimization of Ti-Al-Nb Alloy computer Simulated by Phase Field Approach

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Journal of Materials sci.nce & Technology 2004年第3期20卷 245-248页

作者： Wei GUO Yaping ZONG Gang WANG Liang ZUO Department of Materials sci.nce and eng.neeing,Northeastern University,Shenyang 110004, China dept. of Mat. sci. and eng. Northeastern Univ. Shenyang 110004 China

The effects of applied tensile strain on the coherent α_2→O-phase transformation in Ti-Al-Nb alloys are explored bycomputer simulation using a phase-field method. The focus is on the influence of the applied strain direction onthe microstructure and volume fraction of the O-phase precipitates. It is found that altering applied strain directioncan modify microstructure of Ti-25Al-10～12Nb (at. pct) alloy during α_2→O-phase transformation effectively andfull laminate microstructure in the Ti-25Al-10Nb (at. pct) alloy can be realized by an applied strain only along thedirection 30°away from the α_2 phase in magnitude equivalent to the stress-free transformation strain. Thesimulation also shows that not only the magnitude of applied strain but also the applied strain direction influencesthe O-phase volume fraction and the effect of strain direction on the volume fraction is up to 25%.

关键词： Phase field simulation Strain induced phase transformation Ti-Al-Nb alloy computerization materials Microstructure evoutionv Precipitates geometry Microstructure design

Structure and Magnetic Properties of Y(Fe_(1-x)Co_x)_ (11.3) Nb_(0.7)

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Journal of Rare Earths 2001年第1期19卷 25-28页

作者：罗广圣李劲松 dept. of Mat. sci. and eng. Nanchang Univ. Nanchang 330047 China

The structure and magnetic properties of the intermetallic compounds Y(Fe 1- x Co x ) 11.3 Nb 0.7 ( x =0, 0 05, 0 1, 0 2) were studied by X ray diffraction and magnetic property measurements. X ray diffraction patterns and thermomagnetic curves show that all compounds almost exhibit single phase. All Y(Fe 1- x Co x ) 11.3 Nb 0.7 compounds ( x =0, 0 05, 0 1, 0 2) crystallize in ThMn 12 type structure. Substitution of Co for Fe leads to a clear increasing of Curie temperature and a monotonic decreasing of lattice constants. At room temperature the composition dependence of saturation magnetization exhibits a maximum at about x =0 1～0 2. The magnetocrystalline anisotropy field at room temperature at first increases and then decreases with the increasing of Co content.

关键词： rare earths ThMn 12 type structure Curie temperature saturation magnetization anisotropy field

Massive Si Phase and Its Growth Mechanism in Al-Si Casting Alloy

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Journal of Materials sci.nce & Technology 2004年第5期20卷 589-591页

作者： Heng.heng.LIAO and Guoxiong SUNDepaxtment of Materials sci.nce and eng.neering, Southeast University, Nanjing 210018, China dept. of Mat. sci. and eng. Southeast Univ. Nanjing 210018 China

Optical microscope and scanning electron microscope were used to observe the microstructure of the AI-11.6%Si and AI-11.6%Si-0.4%Mg alloys and the morphology of the massive silicon particles. It is found that the massive silicon phase, observed in the unfully modified alloys with 0.010%Sr, disappears completely in the alloys fully modified with 0.020%Sr. The serrations and reentrant edges shown in the massive silicon particles with the conventional casting indicate that the TPRE mechanism plays an important role in the growth of the massive silicon phase. The ripples and steps suggest that the "lateral microscopic growth" may be another operating mechanism.

关键词： Al-Si alloy Massive silicon Microstructure Growth mechanism

Aligned Solidification Structure of the MnBi Phase in Semisolidified Bi-Mn Alloy with a Static Magnetic Field

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Journal of Materials sci.nce & Technology 2004年第3期20卷 311-314页

作者： Zhongming REN Hui WANG Kang Deng.Kuangdi XU Department of Materials sci.nce and eng.neerng,Shanghai University,Shanghai 200072, China dept. of Mat. sci. and eng. Shanghai Univ. Shanghai 200072 China

The solidification structure of Bi-3 wt pct Mn alloy grown up in the semisolid zone under the influence of a staticmagnetic field (up to 1.0 T) and the relation of the magnetic property with the solidification structure have beeninvestigated experimentally. It was shown that the primary phase MnBi crystals in the alloy aligned and oriented alongthe direction of the applied magnetic field. The orientating tendency and the average leng.h of the elongated MnBicrystals increased with the increase of the applied field and the solidification time. Moreover, the remanence of thealloy along the aligned direction of the MnBi phase in the case of solidification with a magnetic field was apparentlyanisotropic and nearly double of that without the magnetic field. This indicated that the MnBi crystals orientedand aligned along their easy magnetization axis. A model was proposed to explain the alignment and orientationgrowth of the MnBi crystals in a magnetic field in terms of the magnetic anisotropy of the crystals and the magneticinteraction between them.

关键词： Magnetic field Bi-Mn alloy MnBi Solidification

Preparation and Electromechanical Properties of PVDF Matrix Piezoelectric Composites Containing Highly Oriented BaTiO_3 Whiskers

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Journal of Materials sci.nce & Technology 2004年第4期20卷 441-444页

作者： Xuetao LUO, Lifu CHEN, Xiaojun CHEN and Qianjun HUANGDepartment of Materials sci.nce and eng.neering, Xiamen University, Xiamen 361005, China dept. of Mat. sci. and eng. Xiamen Univ. Xiamen 361005 China

The piezoelectric composites containing highly oriented BaTiO3 whiskers as active phase and PVDF as matrix have been prepared by micro-hole extrusion and orientation in carried fibers. The morphology of oriented BaTiO3 whiskers and microstructure of the composites were observed by SEM. As for its electromechanical properties, it is found that the dielectric constant, piezoelectric constant and remnant of polarization in the BaTiO3 whisker-PVDF composite are considerably higher than that in the BaTiO3 powders-PVDF composite, while the loss factors follow the opposite trend. For the BaTiO3 whisker-PVDF composite, the values of ε, d33 and Pr parallel to the whisker orientation (normal specimen) are much higher than that perpendicular to the whisker orientation (parallel specimen). The significant effects of the connective passages of active phase on electromechanical properties of the piezoelectric composites has also been investigated.

关键词： Piezoelectric composite BaTiO3 whiskers Electromechanical properties Polarization Connective passages

Materials Design of Microstructure in Grain Boundary and Second Phase Particles

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Journal of Materials sci.nce & Technology 2003年第2期19卷 97-101页

作者： Yaping ZONG and Liang ZUODepartment of Materials sci.nce and eng.neering, Northeastern University, Shenyang 110004, China dept. of Mat. sci. and eng. Northeastern Univ. Shenyang 110004 China

A concept of microstructure design for materials or materials microstructure eng.neering is proposed. The argument was suggested based on literature review and. some our new research work on second phase streng.hening mechanisms and mechanical property modeling of a particulate reinforced metal matrix composite. Due to development of computer technology, it is possible now for us to establish the relationship between microstructures and properties systematically and quantitatively by analytical and numerical modeling in the research scope of computerization materials. Discussions and examples on intellectual optimization of microstructure are presented on two aspects: grain boundary eng.neering and optimal geometry of particulate reinforcements in two-phase materials.

关键词： Microstructure design Particulate reinforcement Grain boundary eng.neering Streng.hening mechanism Eshelby approach Numerical modelling

Transfer kinetics of phenol between aqueous phase and N,N-di(1-methyl-heptyl) acetamide in kerosene

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Journal of Environmental sci.nces 2000年第2期12卷 19-23页

作者： Zhu-xian, Y. Hui-fang, D. Qi-hong, Z. Zu-ming, Z. dept. of Environmental sci./eng. Fudan University Shanghai 200433 China

The transfer kinetics of phenol between aqueous phase and N,N di(methyl heptyl) acetaminde (N503) in kerosene has been studied using Lewis cell technique. The effects of the factors including the concentrations of phenol in aqueous phase and organic phase, the concentration of N503 in organic phase, the acidity of aqueous phase, the stirring speed and the temperature on the rates of forward and backward extraction of phenol have been examined. The regularity of extraction rate has been obtained. According to experimental results, the rates of both forward and backward extraction of phenol might be controlled by diffusion process. The diffusion step of phenol from aqueous phase to interface for forward extraction and from interface to aqueous phase for backward extraction might be the rate controlling steps.

关键词： phenol transfer kinetics N,N di(1 methyl heptyl) acetamide CLC number: X703 Document code: A Introduction