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science china(Technological sciences) 2010年第1期53卷 242-247页

作者： DONG ZhenWei1,2,WU YaoMing1,MA LiQun2,SHEN XiaoDong2 & WANG LiMin1 1 State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of sciences,C hangchun 130022,china 2 college of material science and engineering,nanjing university of technology,nanjing 210009,china 1. State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The(La0.67Mg0.33)1-xTixNi2.75Co0.25(x = 0,0.05,0.10,0.15 and 0.20,at%) alloys were synthesized by arc melting and subsequent heat solid-liquid diffusing *** structure,electrochemical properties and kinetic characteristics of the alloys were investigated *** results showed that all the alloys mainly consisted of the(La,Mg)Ni3,LaNi5 phases,and the lattice parameters and the cell volumes of the(La,Mg)Ni3 and LaNi5 phases decreased with increasing Ti *** alloy electrodes could be activated to reach their maximum discharge capacity within five *** cycle life after 100 charge/discharge cycles(C100/Cmax) and the high-rate dischargeability at a discharge current density of 1200 mA/g first increased and then *** the results showed that low-Ti content in AB3-type hydrogen storage alloys was beneficial to improvements of the overall electrochemical properties,and the optimum overall electrochemical performance of the alloy electrodes was obtained when x = 0.05.

关键词： AB3-type alloy metal hydride electrode microstructure electrochemical property kinetic characteristic

H814-902/不饱和聚酯树脂/淤泥体系收缩研究

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武汉理工大学学报 2010年第1期32卷 51-55页

作者：严玉蒋海青王晓钧张亚妮宋立园张冬梅张萍南京工业大学材料科学与工程学院南京210009 金陵帝斯曼树脂有限公司南京210038

在淤泥填充不饱和聚酯树脂的新体系中加入低收缩添加剂H814-902控制固化收缩。通过体积收缩率计算,研究不饱和聚酯树脂/淤泥体系、不饱和聚酯树脂/淤泥/低收缩添加剂体系收缩性能和抗弯强度。研究结果表明:当低收缩添加剂、不饱和聚酯... 详细信息

在淤泥填充不饱和聚酯树脂的新体系中加入低收缩添加剂H814-902控制固化收缩。通过体积收缩率计算,研究不饱和聚酯树脂/淤泥体系、不饱和聚酯树脂/淤泥/低收缩添加剂体系收缩性能和抗弯强度。研究结果表明:当低收缩添加剂、不饱和聚酯树脂、淤泥之间的质量比为18∶100∶100时,其体系收缩率达到将其用于低收缩片状模塑料的要求;当玻璃纤维的质量分数为30%时,其抗弯强度达到低收缩片状模塑料强度100 MPa的要求。研究中首次尝试采用高分辨魔角旋转核磁共振(HR/MAS-NMR)方法,并结合SEM方法分析不饱和聚酯树脂/淤泥/低收缩添加剂体系抗收缩机理,提出该体系中空穴、两相岛屿状结构以及固化反应中交联度的下降是抑制体系收缩的主要原因。

关键词：低收缩添加剂淤泥 HR/MAS-NMR 片状模塑料

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 university of science and technology, nanjing 210094, china 2 college of Civil engineering, nanjing university of technology, nanjing 210009, 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

Analysis of variance for testing method of cement in determination of strength

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Progress in Natural science:materials International 2011年第4期21卷 341-346页

作者： Hong HUANG,Xiao-dong SHEN State Key Laboratory of materials-Oriented Chemical engineering,college of material science and engineering, nanjing university of technology,nanjing 210009,china State Key Laboratory of materials-Oriented Chemical engineering College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The statistical tools such as descriptive statistics,full factorial design and analysis of source of variation were used to identify the potential factors that impact the validity of testing method for determining the strength of *** results showed that personal error impacted both accuracy and precision of test *** time associated with temperature fluctuation resulted in strength variation but did not impact the precision of test in all curing *** compactions did not impact the precision of test but resulted in the strength variation on 3 d and 28 d *** methods for the initial moist air curing significantly impacted the precision of testing method and resulted in the strength variation of cement on 1 d.

关键词： testing method of cement analysis of variance strength accuracy precision

Statistical study of cement additives with and without chloride on performance modification of Portland cement

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Progress in Natural science:materials International 2011年第3期21卷 246-253页

The effectiveness of cement additives with and without chloride on the fluidity and the strength development of Portland cement was compared by using statistical full factorial *** experimental results show that the cement additive containing CaCl2and Ca(NO3)2can enhance early strength of cement ***,Ca(NO3)2is less effective than CaCl2even if it is combined with other organic chemicals such as alkanolamine and *** significant difference is found between CaCl2and Ca(NO3)2influencing the fluidity and 28 d strength of *** fluidity is determined by saccharide and its interaction with *** 28 d strength enhancement is determined by *** fluidity as well as the mechanical performance of treated cement can be significantly improved by combining Ca(NO3)2with TIPA and saccharide.

关键词： Portland cement cement additive accelerator type fluidity strength development full factorial design

A NOVEL INTERPRETATION OF CONCENTRATION DEPENDENCE OF VISCOSITY OF DILUTE POLYMER SOLUTION

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Chinese Journal of Polymer science 2000年第1期18卷 57-67页

作者： Yan Pan Rong-shi Cheng college of material science and engineering, South china university of technology, Guangzhou 510641, china college of Chemistry and Chemical engineering, nanjing university, nanjing 210093, china S china Univ Technol Coll Mat Sci & Engn Guangzhou 510641 Peoples R China nanjing Univ Coll Chem & Chem Engn Nanjing 210093 Peoples R China

The concentration dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of a new concept of the self-association of polymer chains in dilute solution. The apparent self-association constant is defined as the molar association constant divided by the molar mass of individual polymer chain and is numerically interconvertible with the Huggins coefficient. The molar association constant is directly proportional to the effective hydrodynamic volume of the polymer chain in solution and is irrespective of the chain architecture. The effective hydrodynamic volume accounts for the non-spherical conformation of a short polymer chain in solution and is a product of a shape factor and hydrodynamic volume. The observed enhancement of Huggins coefficient for short chain and branched polymer is satisfactorily interpreted by the concept of self-association. The concept of self-association allows us to predict the existence of a boundary concentration C-s(dynamic contact concentration) which divides the dilute polymer solution into two regions.

关键词： self-association polymer solution viscosity concentration dependence

Dynamic damage and stress-strain relations of ultra-high performance cementitious composites subjected to repeated impact

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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 engineering,nanjing university of science and technology,nanjing 210094,china 2 college of materials science and engineering,Southeast university,nanjing 211189,china 1. Department of materials science and engineering 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

Molecular group dynamics study on slip flow of thin fluid film based on the Hamaker hypotheses

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science china(Technological sciences) 2010年第7期53卷 1833-1838页

作者： ZHOU JianFeng, SHAO ChunLei & GU BoQin college of Mechanical and Power engineering, nanjing university of technology, nanjing 210009, china 1. college of Mechanical and Power engineering Nanjing University of Technology Nanjing 210009 China

The thin fluid film was assumed to consist of a number of spherical fluid molecular groups and the attractive forces of molecular group pairs were calculated by the derived equation according to the three Hamaker homogeneous material hypotheses. Regarding each molecular group as a dynamics individual, the simulation method for the shearing motion of multilayer fluid molecular groups, which was initiated by two moving walls, was proposed based on the Verlet velocity iterative algorithm. The simulations reveal that the velocities of fluid molecular groups change about their respective mean velocities within a narrow range in steady state. It is also found that the velocity slips occur at the wall boundary and in a certain number of fluid film layers close to the wall. Because the dimension of molecular group and the number of group layers are not restricted, the hypothetical thickness of fluid film model can be enlarged from nanometer to micron by using the proposed simulation method.

关键词： Hamaker hypotheses molecular group velocity slip Lennard-Jones potential

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 university, nanjing 210096, Jiangsu, china 2.college of Computer science and engineering, nanjing university of technology, nanjing 210009, 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, 60303024). National Grand Fundamental Research 973 Program of china (2002CB312000) 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 university of Information science & technology, nanjing 210044, china 2 college of Automation engineering, nanjing university of Aeronautics and Astronautics, nanjing 210016, 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