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science China(Technological sciences) 2010年第6期53卷 1520-1525页

作者： LAI JianZhong1 & SUN Wei2.1 Department of materials science and {2.,nanjing university of science and Technology,nanjing 2.0094,China 2.college of materials science and engineering,Southeast university,nanjing 2.1189,China 1. Department of materials science and {2. Nanjing University of Science and Technology Nanjing 210094 China2. College of Materials Science and Engineering Southeast University Nanjing 211189 China

Ultra-high performance cementitious composites (UHPCC) were prepared by replacing 60% of cement with ultra-fine industrial waste *** dynamic damage and compressive stress-strain relations of UHPCC were studied using split Hopkinson pressure bar (SHPB).The damage of UHPCC subjected to repeated impact was measured by the ultrasonic pulse velocity *** show that the dynamic damage of UHPCC increases linearly with impact times and the abilities of repeated impact resistance of UHPCC are improved with increasing fiber volume *** stress waves on impact were recorded and the average stress,strain and strain rate of UHPCC were calculated based on the wave propagation *** effects of strain rate,fibers volume fraction and impact times on the stress-strain relations of UHPCC were *** show that the peak stress and elastic modulus decrease while the strain rate and peak strain increase gradually with increasing impact times.

关键词： ultra-high performance cementitious composites (UHPCC) split Hopkinson pressure bar (SHPB) repeated impact damage stress-strain

Dynamic Mechanical Behaviour of Ultra-high Performance Fiber Reinforced Concretes

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Journal of Wuhan university of Technology(materials {2.) 2008年第6期23卷 938-945页

作者：赖建中 Department of materials science & {2. Nanjing University of Science & Technology

Ultra-high performance fiber reinforced concretes （UHPFRC） were prepared by replacing 60% of cement with ultra-fine industrial waste powder. The dynamic mechanical behaviour of UHPFRC with different fiber volume fraction was researched on repeated compressive impact in four kinds of impact modes through split Hopkinson pressure bar （SHPB）. The experimental results show that the peak stress and elastic modulus decrease and the strain rate and peak strain increase gradually with the increasing of impact times. The initial material damage increases and the peak stress of the specimen decreases from the second impact with the increasing of the initial incident wave. Standard strength on repeated impact is defined to compare the ability of resistance against repeated impact among different materials. The rate of reduction of standard strength is decreased by fiber reinforcement under repeated impact. The material damage is reduced and the ability of repeated impact resistance of UHPFRC is improved with the increasing of fiber volume fraction.

关键词： ultra-high performance fiber reinforced concretes split Hopkinson pressurebar dynamic repeated impact

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science China(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2. LIU Ping2. DONG Qiming2.& LI Hejun1 1. college of materials {2. and engineering, Northwestern Polytechnical university, Xi’an 710072. China 2. college of materials {2. and engineering, Henan university of {2. and Technology, Luoyang 471003, China 1. college of materials {2. and engineering Northwestern Polytechnical University 710072 Xi’an China 2. college of materials {2. and engineering Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

Comparison of the fracture process of the rubberized concrete and plain concrete under bending load

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science China(Technological sciences) 2010年第6期53卷 1526-1533页

作者： ZHANG YaMei1,WANG Chao2.LU Yi1 & MA AiBin2.1 Jiangsu Key Laboratory of Construction materials,Southeast university,{2. 2.1189,China 2.college of materials science and engineering,hohai university,nanjing 2.0098,China 1. Jiangsu Key Laboratory of Construction materials Southeast University Nanjing 211189 China2. College of Materials Science and Engineering Hohai University Nanjing 210098 China

Acoustic emission (AE) technique is employed to investigate the damage process of the notched plain concrete and rubberized concrete specimens under 3-point bending *** signals in the fracture process of notched specimens are illustrated by analyzing the distribution of amplitude and hit rate of AE *** signals in the rubberized concrete have lower activity and amplitude than in the plain *** AE location analysis,it is found that the high energy events mainly are distributed near the notch *** to AE energy,the fracture process zone (FPZ) is *** comparing the FPZ of both concretes,it is found that the incorporation of rubber particles in concrete can greatly alleviate the damage process of concrete specimens and the damage zone in the rubberized concrete is much smaller than in the plain *** moment tensor is also used to analyze the type of cracks and it is found that tensile cracks dominate the early period of loading,while shear cracks become dominant with propagation of cracks in late load period.

关键词： concrete rubberized concrete acoustic emission damage moment tensor

Synthesis and Lubrication of Phosphorylcholine Derivative

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Journal of Bionic engineering 2010年第3期7卷 254-258页

作者： Zhenliang Qiao~1, Dangsheng Xiong~1, Lude Lu~2. Pengju Jiang~2.1. Department of materials science and {2., nanjing university of science and Technology, nanjing 2.0094, P.R. China 2. School of Chemical {2., nanjing university of science and Technology, nanjing 2.0094, P. R. China [a] Department of materials science engineering Nanjing University of Science Technology Nanjing 210094 P.R. China [b] School of Chemical Engineering Nanjing University of Science Technology Nanjing 210094 P. R. China

The monomer of phosphorylcholine derivative, O-(5-（2.methacryloxy）-3, 3-dimethyl-3-azapentyl)-O’-（ω-hydroxy-octyl）-phosphatequaternary ammonium salt, was designed and synthesized successfully. It was characterized by the spectra ofHNMR and Mass spectra （ESI+）, and every signal was assigned. Then the lubricating characteristics of the phosphorylcholinederivative were investigated on the tribological setup of ball-oh-flat. The Ultra-High Molecular Weight Polyethylene（UHMWPE） flat was rotated against a stainless steel ball with 6 mm diameter. The load was 2.3 N, which corresponded to amaximal Hertz contact pressure of 2. MPa. Water, phosphorylcholine derivative, and Acrylic Acid （AA） solution were used aslubricants, respectively. Compared with AA, the phosphorylcholine derivative shows significant lubrication. It can be stronglyhydrated under water due to the charged segment in chemical structure. The thick water layers within the chains serves asboundary lubricants, and this is thought to be the molecular origins of lubricating behavior.

关键词： artificial joint articular cartilage molecular lubrication mechanism phosphorylcholine synthesis UHMWPE

Internal relative humidity and creep of concrete with modified admixtures

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Progress in Natural science:materials International 2011年第5期21卷 426-432页

作者： Zhi-hai HE~(1,2.,Chun-xiang QIAN~(1,2. 1.college of materials {2. and engineering,Southeast university,nanjing 2.1189,China 2.Jiangsu Key Lab of Construction materials,nanjing 2.1189,China [a] college of materials {2. and engineering Southeast University Nanjing 211189 China [b] Jiangsu Key Lab of Construction materials Nanjing 211189 China

The creep characteristics and internal relative humidity(IRH) of concrete with shrinkage reducing admixtures(SRA),poly vinyl alcohol fiber(PVAF) and a mixture of fly ash and slag(MFS) were investigated by the self-made loading *** pore structure was tested,and the relationship of creep and IRH of concrete was *** results indicate that MFS and SRA reduce the total creep and delay the change of ***,the effect of PVAF is contrary,relative to MFS and *** total creep depends largely on drying *** basic creep of concrete is similar,which is significantly influenced by volume fraction of pores whose diameter is between 3.5 nm and 50 nm to the total pore(VP),and IRH of concrete is connected with *** is easy to obtain a good linear relationship predicting the creep of concrete according to the change of IRH.

关键词： modified admixture internal relative humidity total creep drying creep basic creep porosity

Effect of Zn^(2.) Content on the Microstructure and Magnetic Properties of Nanocrystalline Ni_(1-x)Zn_xFe_2._4 Ferrite by a Spraying-coprecipitation Method

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Journal of Wuhan university of Technology(materials {2.) 2010年第3期25卷 429-431页

作者：刘银 college of materials {2. and engineering Anhui University of Science and Technology

Nanocrystalline Ni1-xZnxFe2.4 ferrites with 0≤x≤1 were successfully prepared by a spraying-coprecipitation *** microstructure was investigated by using XRD and *** properties were measured with vibrating sample magnetometer（VSM） at room *** results show that the grain size of nanocrystalline Ni1-xZnxFe2.4 ferrite calcined at 600 ℃ for 1.5 h is about 30 *** parameter and specific saturation magnetization Ms of nanocrystalline Ni1-xZnxFe2.4 ferrite increase with the Zn^2. ions content at room temperature,and maximum Ms is 66.8 A·m^2.kg^-1 as the Zn^2. ions content is around 0.5,and coercivity Hc of the nanocrystalline Ni1-xZnxFe2.4 ferrite decreases with Zn^2. ions content.

关键词： nanocrystalline material Ni-Zn ferrite spraying-coprecipitation method magnetic properties microstructure

Three-dimensional elasticity solution of simple-supported rectangular plate on point supports, line supports and elastic foundation

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science China(Technological sciences) 2009年第3期52卷 584-589页

作者： XU YePeng1 & ZHOU Ding2.1 School of science, nanjing {2. of science and Technology, nanjing 2.0094, China 2.college of Civil engineering, nanjing {2. of Technology, nanjing 2.0009, China 1. School of science Nanjing University of Science and Technology Nanjing 210094 China 2. college of Civil engineering Nanjing University of Technology Nanjing 210009 China

This paper studies the bending of simple-supported rectangular plate on point supports, line supports and elastic foundation. On the basis of three-dimensional elasticity theory, the exact expressions of the displacement functions, which satisfy the governing differential equations and the simply supported boundary conditions at four edges of the plate, are analytically derived. The reaction forces of the in- termediate supports are regarded as the unknown external forces acting on the lower surface of the plate. The unknown coefficients are then determined by the boundary conditions on the upper and lower surfaces of the plate. Comparing the numerical results obtained from the proposed method to those obtained from Kirchhoff plate theory, Mindlin plate theory and those obtained from the commer- cial finite element software ANSYS, the high accuracy of the present method has been demonstrated.

关键词： rectangular plate point support line support elastic foundation displacement stress three-dimensional elasticity solution

Web Application Comprehension Based on Dependence Analysis

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Wuhan university Journal of Natural sciences 2004年第5期9卷 731-734页

作者： WU Jun-hua 1,2., XU Bao-wen 1 , JIANG Ji-xiang 1 1.Department of Computer science and engineering, Southeast {2., nanjing 2.0096, Jiangsu, China 2.college of Computer science and engineering, nanjing {2. of Technology, nanjing 2.0009, Jiangsu , China Southeast university Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***) Najing university of Technology College of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.41156.37) (ISNI:***) Southeast university Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***)

Many research indicate a lot of money and time are spent on maintaining and modifying program delivered. So the policies to support program comprehension are very important. Program comprehension is a crucial and difficult task. Insufficient design, illogical code structure, short documents will enhance the comprehensive difficulty. Developing Web application is usually a process with quick implementation and delivery. In addition, generally a Web application is coded by combining mark language statements with some embedded applets. Such programming mode affects comprehension of Web applications disadvantageously. This paper proposes a method to improving understanding Web by dependence analysis and slice technology. Key words Web application comprehension - program dependence - hyper graph - pogram slicing CLC number TP 311 Foundation item: Supported in part by the Young Scientist’s Fund of NSFC (60373066, 6030302.). National Grand Fundamental Research 973 Program of China (2.02.B312.00) and National Research Foundation for the Doctoral Program of Higher Education of ChinaBiography: WU Jun-hua (1965-), female, Ph. D. research direction: software engineering.

关键词： Web application comprehension program dependence hyper graph pogram slicing

Resolution method for overlapping peaks based on the fractional-order differential

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science China Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2.& ZHENG Gang2.1 college of Information & Control, nanjing {2. of Information science & Technology, nanjing 2.0044, China 2.college of Automation engineering, nanjing {2. of Aeronautics and Astronautics, nanjing 2.0016, China 1. college of Information & Control Nanjing University of Information Science & Technology Nanjing 210044 China 2. college of Automation engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak