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Molecular Dynamics Simulation of Dealloyed Layer-induced Tensile Stress in Cu_3Au

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Journal of University of science and Technology Beijing 2001年第4期8卷 295-298页

作者： Qikai L, Yue Zhang, Mark Hoffman, Wuyang Chu 1)materials science and engineering school. University of science and Technology Beijing. Beijing 100083, china 2)school of materials science & engineering, University of New South Wales, Sydney 2052, Austral Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Univ New S Wales Sch Mat Sci & Engn Sydney NSW 2052 Australia

During stress corrosion cracking of Cu3Au alloy, there is a dealloyed layer on its surface because of preferential dissolution of Cu, and there is a linear distribution of Cu vacancy concentration in the dealloyed layer. Molecular dynamics simulation has been done on the three-dimensional crystal (about 148 000 atoms) by employing the embedded-atom method (EAM) potential. Simulation shows that Cu3Au crystal in which there is a dealloyed layer on one surface and one end is fixed will be deflected after relaxing for a long time because of a tensile stress generated at or near the dealloyed layer interface. The deflection and then the tensile stress increase with increasing the depth of dealloyed layer and the vacancy concentration in the dealloyed layer.

关键词： dealloyed layer-induced stress molecular dynamics simulation Cu3Au

Whisker Orientation Function and Elastic Modulus of the as-cast 20% SiC_W/Mg Composite

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Rare Metals 2001年第4期20卷 270-274页

作者： Chuanhai Jiang1, Jiansheng Wu1, Mingyi Zheng2, Dezun Wan 2 1) Key Laboratory for High Temperature materials and Tests of the Ministry of Education, Shanghai Jiaotong University. Shanghai 200030, china 2) school of materials science and engineering, Harb Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

The relationship between the plane-orientation function and the space-orientation function of whiskers in whisker-reinforced metal matrix composites was analyzed theoretically. The actual orientation of whiskers in the as-cast 20%SiCw/Mg composite (SiCw content in volume fraction) were investigated, and the elastic modulus of the composite was measured with an ultrasonic velocity analyzer. Results show that there is an evident difference between the plane-orientation function and the space-orientation function of whiskers and the space-orientation function can represent the actual condition of the composite. Only by using the space-orientation function of whiskers, the difference of elastic modulus of the as-cast composite in different directions can be explained reasonably.

关键词： SiC whisker Mg composite whisker orientation elastic modulus

The Micro/Nanostructure Characteristics and the Mechanical Properties of Hemifusus tuba Conch Shell

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Journal of Bionic engineering 2010年第4期7卷 3+308-313页

作者： Yan Liang~1,Jie Zhao~2,Chengwei Wu~1 1.State Key Laboratory of Structural Analysis for Industrial Equipment,Department of engineering Mechanics,Dalian University of Technology,Dalian 116024,P.R.china 2.school of materials science and engineering,Dalian University of Technology,Dalian 116024,P.R.china [a] State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian 116024 P. R. China [b] School of Materials Science engineering Dalian University of Technology Dalian 116024 P. R. China

The mollusk shell mobilizes calcium from environment for skeletal *** occurs through synthesizing solidsin solution in the presence of organic molecules of specific interior regions of the conch *** ultrastructure and microhardnessof the Hemifusus tuba conch shell living in the Huang/Bo sea area are investigated in the *** is shown that thecomposition and microstructure of the mollusk shell vary in different *** prodissoconch shell consists only of aragonitewith the crossed-lamellar *** the spiral shell and the body shell of the Hemifusus tuba conch shell arecomposed of one calcite layer and several aragonite *** calcite layer consists of cylindrical grains,but the aragonitelayers are crossed-lamellar ultrastructure at three size *** minimum structure size (the third-order lamella) is at about20 nm - 80 *** margin of shell aperture is only composed of calcite with cylindrical *** natural optimization of theshell microstructure is intimately due to the growth of the Organic *** different positions the microhardness of molluscshell is different due to different crystal structures and crystal *** growth process of shells allows a constantrenewal of the material,thus enabling their functional adaptation to external environments.

关键词： conch shell microstructure aragonite calcite crossed-lamellar

A whisker-like carbon composite for the immobilization of laccase and its bioelectrochemistry

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science china Chemistry 2010年第6期53卷 1332-1336页

作者： MA GuoXian1,2,ZHONG QingDong2 & LU TianHong3 1Department of Chemical engineering,Shanghai Institute of Technology,Shanghai 200233,china 2school of materials science and engineering,Shanghai University,Shanghai 200072,china 3Department of Chemistry,Nanjing Normal University,Nanjing 210097,china 1. Department of Chemical engineering Shanghai Institute of Technology Shanghai 200233 China2. School of Materials Science and Engineering Shanghai University Shanghai 200072 China3. Department of Chemistry Nanjing Normal University Nanjing 210097 China

A novel mesoporous carbon/whisker-like carbon (MCWC) composite was used for the immobilization of laccase (Lac) and its bioelectrochemical behaviors were *** was confirmed by XPS that Lac was strongly adsorbed on the surface of the MCWC *** cyclic voltammetric results showed that the immobilized Lac underwent a direct quasi-reversible electrochemical *** value of the electron transfer rate constant ks was estimated to be 0.770 s-1,indicating a reasonably fast electron transfer between the immobilized Lac and the underlying *** surface concentration (I-) of Lac was estimated to be 2.730 × 10-12 mol/*** experimental results showed that the immobilized Lac displayed an appreciable electrocatalytic activity to the electrochemical reduction of *** properties could be attributed to the particular structure of loosely packed nanometer-scale carbon whiskers and the existence of a large amount of oxygen-containing *** immo- bilization method and the novel carrier (MCWC) may find new applications in fabricating the biocatalysts for biofuel cells.

关键词： laccase whisker-like carbon composite direct electrochemical reaction oxygen bioelectrochemistry

A simple method of synthesizing multi-wall carbon nanotubes/SnO core/shell nanostructure

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Rare Metals 2007年第S1期26卷 191-194页

作者： SUN Xue1),CHU Yi2),WANG Dawei3),DU Jinhong3),ZHANG Baoyou2),and WANG Fuping1)1) school of science,Harbin Institute of Technology,Harbin 150001,china 2) school of materials science and engineering,Harbin Institute of Technology,Harbin 150001,china 3) Shenyang National Laboratory for materials science,Institute of Metal Research,Chinese Academy of sciences,Shenyang 110016,china Harbin Inst Technol Sch Sci Harbin 150001 Peoples R China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China Chinese Acad Sci Inst Met Res Shenyang Natl Lab Mat Sci Shenyang 110016 Peoples R China

Multi-wall carbon nanotubes(MWNTs)/SnO core/shell nanosturcture was synthesized by a simple solution-based method,in which SnCl2 was solved in distilled water containing dispersed MWNTs,then stired,filtered and washed in ambient atmosphere,finally dryed in air at 90 ℃ for 6 *** MWNTs/SnO core/shell nanostructure was characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM).It is found that surface defects of MWNTs are necessary for the deposition of *** mechanism of the SnO nanocoating formation through the hydrolysis of SnCl2 in water(4SnCl_2+2H_2O-Sn_4(OH)2Cl_6+2HCl) was presented.

关键词： precipitate isothermal aging thermodynamic calculation phase diagram high nitrogen austenitic stainless steel

Application of MgO-CaO Refractories in Secondary Refining Furnaces

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china's Refractories 2012年第1期21卷 11-16页

作者： GAO Xinkui1,YIN Guoxiang1,2 1 Yingkou Qinghua Refractories Co. ,Ltd. ,Dashiqiao 115100,china 2 school of materials science and engineering,University of science and Technology Beijing,Beijing 100083,china Yingkou Qinghua Refractories Co. Ltd Dashiqiao 115100 China school of materials science and engineering University of Science and Technology Beijing Beijing 100083 China

The development status, production technology and characteristics of MgO-CaO refractories are introduced, covering MgO-CtlO clilnkers, fired MgO-CaO bricks and unburned MgO-CaO-C bricks. The applications o! MgO-CaO re... 详细信息

关键词： magnesia calcia clinkers magnesia calciabricks: magnesia calcia carbon bricks secondaU refining

Photoluminescence Characterization of NASICON Material

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稀有金属材料与工程 2006年第S3期 535-537页

作者： Yuehua He~1 Baofu Quan~1 Ying Wang~2 Chuanhui Cheng~1 Fengmin Liu~1 Biao Wang (1.College of Electronic science and engineering,Jilin University,Changchun 130012,china) (2.school of materials science and engineering,Dalian Jiaotong University,Dalian 116028,china)

Besides gas sensitivity,NASICON （Na super ion conductor） material has luminescence *** this paper,the photoluminescence properties of NASICON and doped-NASICON material are *** NASICON material was synthesized by conventional sol-gel process,and doped with Er2O3,Tm2O3,Dy2O3,CsCl by 1%,3%,5% （mass ratio）,*** ultraviolet light （325 nm,He-Cd laser） excited luminescent emissions of the resulted powders are recorded *** in the 330 nm to 650 nm *** main peak of the pure NASICON is found at the wavelength of 474 nm （blue light）,the transition energy is 2.616 *** luminescent intensity is weakened obviously after doping with Er2O3and Tm2O3,but is increased after doping with Dy2O3and 3% CsCl.

关键词： photoluminescence NASICON luminescent intensity wavelength

Numerical Simulation Study on the Surface Deflection of Cylindrical Shallow Shell

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武汉理工大学学报 2006年第S2期28卷 577-581页

作者： XING Zhongwen~1 BAO Jun~1 LIU Zhongyuan~1 YANG Yuying~2 SUN Zhenzhong~2 1.school of Mechanical and Electrical engineering,Harbin Institute of Technology,Harbin 150001,china 2.school of materials science and engineering,Harbin Institute of Technology,Harbin 150001,china school of Mechanical and Electrical engineering Harbin Institute of TechnologyHarbin 150001China school of materials science and engineering Harbin Institute of TechnologyHarbin 150001China

The increasing applications of new materials such as high strength low alloy (HSAL) steels and aluminum alloy sheets have lead to greater focus on the surface deflections of auto body panels in the automobile industry in recent *** finite element models of cylindrical shallow shell that can represent auto body panels are *** simulations of forming and unloading of cylindrical shallow shell are carried *** a measurement and evaluation method of the surface deflection is *** simulations of surface deflections with various blank homing forces (BHF) show great agreement with the experi- mental *** influence laws of sheet thickness and material properties such as yield strengthσs,strain-hardening exponent n,anisotropy parameter r and strength coefficient k on the surface deflection are achieved by simulations,which give a basic refer- ence for controlling surface deflections.

关键词： cylindrical shallow shell surface deflection numerical simulation material properties

Slag Corrosion Resistance of MgO-ZrO_2 Refractories

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china's Refractories 2012年第1期21卷 17-21页

作者： YUAN Lin1,CHEN Songlin1,2,ZENG Luju1,LIU Xijun1,WU Xingsheng1,SUN Jialin2 1 Ruitai materials Technology Co. Ltd. ,china Building materials Academy,Beijing 100024,china 2 school of materials science and engineering,University of science and Technology Beijing, Beijing 100083,china Ruitai materials Technology Co. Ltd. China Building Materials Academy Beijing 100024 China school of materials science and engineering University of Science and Technology Beijing Beijing 100083 China

Slag corrosion resistance of MgO -ZrO2 refractories was inrestigated ill this work. The resuhs indicate that in a non-oriented electric steel slag systenl with a high ratio of ealci^t to silica, the slag resistance of MgO - ZrO, refractories can be described as flllows ： ZrO2 reacts with GtO .forming calcium zireonate compound which strengthens the material and blocks the channel of the slag infihration ; however, in an oriented electric steel slag system with a high concentration of silica and the low ratio of calcia to silica, the slag corrosion resistance ofM gO-ZrO： refractories is different ; ZrO2 reaets with CaO forming the ealcium zirconate and simultaneously one more product C2S as well; C2S cam improve corro- sion resistance by blinding pore and enhancing slag viscosity; therefore, it is expected to be the major reason for the enham＇ed corrosion resistance observed for MgO-ZrO2 refractories.

关键词： corrosion resistatlce mechanism magne-sia-zirconia brick : RH degasser