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science china(Technological sciences) 2009年第1期52卷 72-78页

作者： WANG Bo1, WANG RongXiu2.& WU Yong1 1 School of Mathematic science, Chongqing Institute of Technology, Chongqing 400050, china 2.{2. of computer science and Information engineering, Chongqing Technology and Business university, Chongqing 400067, china School of Mathematic science Chongqing Institute of Technology Chongqing China department of computer {2. and Information engineering Chongqing Technology and Business University Chongqing China

The elastic moduli of short-fiber-reinforced foams depend critically on the fiber content and fiber length, as well as on the fiber orientation distribution. Based on periodic tetrakaidecahedrons, the finite element models with short-fiber reinforcement were proposed in this paper to examine the effects of the fiber content and fiber length on Young's modulus. The fiber length distribution and fiber orientation distribution were also considered. The proposed models featured in a three-dimensional diorama with random short-fiber distribution within or on the surfaces of the walls and edges of the closed-cells of polypropylene (PP) foams. The fiber length/orientation distributions were modeled by Gaussian prob-ability density functions. Different fiber volume fractions, different lengths, and different distributions were investigated. The predicted Young's moduli of the PP foams with short-glass-fiber or short-carbon-fiber reinforcement were compared with other theoretic and experimental results, and the agreement was found to be satisfactory. The proposed finite element models were proved to be acceptable to predict the Young's moduli of the grafted closed-cell PP foams with short-fiber reinforcement.

关键词： short-fiber reinforcement Young’s modulus finite element Gaussian distribution

Y_CΩ_(2.)are easy terms

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Chinese science Bulletin 1998年第20期43卷 1707-1709页

作者： ZHAO Xishun 1 and WANG Ju 2.1. department of Mathematics, nanjing {2., nanjing 2.0093, china 2. Institute of Software, Chinese Academy of sciences, Beijing 100080, china department of Mathematics Nanjing University Nanjing China Institute of Software Chinese Academy of Sciences Beijing China

For any natural number n≥1, Y CΩ 2. is an easy term; that is, for any λ term M, λβ+Y\-CΩ 2. =M is consistent, where Y C is Curry fixed point combinator, Ω 2. ≡ω 2. ω 2. and ω 2. ≡λ***...x (there are 2. occurrences of x after λx ). This result is a partial solution to Jacopini’s conjecture: Y CΩ n is an easy term for any natural number n≥2.

关键词： λβ-calculus Kuper’s theorem easy term.

Investigation of the Leaching Behavior of Mortar Pipe Lining in Drinking Water

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Journal of Wuhan university of Technology(Materials science) 2010年第5期25卷 893-896页

作者：高岳毅张亚梅 department of Materials science and {2. Southeast University Jiangsu Key Laboratory of Construction Materials

The leaching behavior of three types of mortars was investigated using a self-design device which could simulate the field conditions of pipe lining. The results by ICP and ESEM measurement show that the developed sla... 详细信息

关键词： leaching pipe lining drinking water slag cement

Theory and methods of global stability analysis for high arch dam

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science china(Technological sciences) 2011年第S1期54卷 9-17页

作者： REN QingWen 1,LI Qiang 1,JIANG YaZhou 2.& JIANG XiaoLan 3 1 department of engineering Mechanics,Hohai {2.,nanjing 2.0098,china 2.College of Water Conservation and Hydropower engineering,Hohai {2.,nanjing 2.0098,china 3 Changjiang Academy of sciences,Wuhan 430010,china department of engineering Mechanics Hohai University Nanjing China College of Water Conservation and Hydropower engineering Hohai University Nanjing China Changjiang Academy of sciences Wuhan China

The global stability of high arch dam is one of the key problems in the safety study of arch dams,but no feasible method with theoretical basis is *** this paper,based on the stability theory of mechanical system,it is demonstrated that the global failure of high arch dams belongs to a physical instability starting from local strength failure,which is the extreme point instability according to the characteristics of load-displacement curve obtained from the failure process of dam-foundation system. So the global failure of dam-foundation system should be studied with the stability theory of mechanical *** is also pointed out that the current stability analysis methods used in engineering are consistent with the stability theory,but not established according to the mechanical system stability theory directly.A perfect method can be obtained through the study of physical disturbance equations.

关键词： high arch dam global stability physical instability extreme point instability

Study on Tribological Properties of Irradiated Crosslinking UHMWPE Nano-Composite

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Journal of Bionic engineering 2009年第1期6卷 7-13页

作者： Lei Xiong, Dang-sheng Xiong, Jia-bo Jindepartment of Materials science and {2., nanjing university of science and Technology, nanjing 2.0094, P. R. china department of Materials science and {2. Nanjing University of Science and Technology Nanjing P. R. China

Ultra High Molecular Weight Polyethylene(UHMWPE)has been widely used as a bearing material for artificial joint replacement over forty *** is usually crosslinked by gamma rays irradiation before its implantation into human *** this study,UHMWPE and UHMWPE/nano-hydroxyapatite(n-HA)composite were prepared by vacuum hot-pressing *** prepared materials were irradiated by gamma rays in vacuum and molten heat treated in vacuum just after *** effect of filling n-HA with gamma irradiation on tribological properties of UHMWPE was investigated by using friction and wear experimental machine(model MM-2.0)under deionized water ***-morphology of worn surface was observed by metallographic *** angle and hardness of the materials were also *** results show that contact angle and hardness are changed by filling n-HA and gamma *** coefficient and wear rate under deionized water lubrication are reduced by filling *** friction coefficient is increased and wear rate is reduced significantly by gamma *** worn surface of unfilled material is mainly characterized as adhesive wear and abrasive wear,and that of n-HA filled material is mainly characterized as abrasive *** gamma irradiation,the degrees of adhesive and abrasive wear for unfilled material and abrasive wear of n-HA filled material are significantly *** and filled materials after irradiation are mainly shown as slight fatigue *** results indicate that UHMWPE and UHMWPE/n-HA irradiated at the dose of 150 kGy can be used as bearing materials in artificial joints for its excellent wear resistance compared to original UHMWPE.

关键词： tribological properties irradiated crosslinking UHMWPE n-HA artificial joints

Fast parallel algorithms for discrete Gabor expansion and transform based on multirate filtering

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science china(Information sciences) 2012年第2期55卷 293-300页

作者： TAO Liang1 & GU JuanJuan2.1School of computer science and Technology,Anhui {2.,Hefei 2.0039,china 2.4} of Electronic Information and Electrical engineering,Hefei {2.,Hefei 2.002.,china School of computer science and Technology Anhui University Hefei China department of Electronic Information and Electrical engineering Hefei University Hefei China

The Gabor transform has long been recognized as a very useful tool for the joint time and frequency analysis in signal *** real time applications,however,were limited due to the high computational complexity of the Gabor transform *** this paper,some novel and fast parallel algorithms for the finite discrete Gabor expansion and transform are presented based on multirate *** analysis filter bank is designed for the finite discrete Gabor transform(DGT)and a synthesis filter bank is designed for the finite discrete Gabor expansion(DGE).Each of the parallel channels in the two filter banks has a unified structure and can apply the FFT and the IFFT to reduce its computational *** computational complexity of each parallel channel does not change as the oversampling rate *** fact,it is very low and depends only on the length of the input discrete signal and the number of the Gabor frequency sampling *** computational complexity of the proposed parallel algorithms is analyzed and compared with that of the major existing parallel algorithms for the finite DGT and *** results indicate that the proposed parallel algorithms for the finite DGT and DGE based on multirate filtering are very attractive for real time signal processing.

关键词： discrete Gabor expansion discrete Gabor transform critical sampling and oversampling multirate filtering analysis and synthesis filter banks

The Microstructure and Mechanical Properties of the Low Carbon Microalloy Steel by High Voltage Electropulse Heating

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材料热处理学报 2004年第5期25卷 635-637页

作者： FANXin-min HuiJing Yinsheng departmentofMaterialsscienceand{2. NanfingUniversityofScienceandTechnologyNanjingChina

The low carbon microalloy steel samples were heated to different temperatures by high voltage electropulse discharge heating method. The temperature of sample increases with the discharge current density. Microstructures were observed by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results show that coexist microstructure of ultrafine ferrite grain and martensite can be obtained by proper high voltage electropulse discharge heating process parameter. The tensile testing indicate that better mechanical properties were obtained, including 758MPa yield strength, 796MPa ultimate strength and 12. total elongation.

关键词：显微结构机械性质晶粒细化低碳微量合金高压电脉冲加热

Uniform estimate for maximum of randomly weighted sums with applications to insurance risk theory

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science china Mathematics 2005年第10期48卷 1379-1394页

作者： WANG Dingcheng~1 SU Chun~2.& ZENG Yong~1 1. School of Management and School of Applied Mathematics,university of Electronic science and Technology of{2.,Chengdu 610054,china 2. department of Statistics and Finance,university of science and Technology of{2.,Hefei 2.002.,china School of Management and School of Applied Mathematics University of Electronic Science and Technology of China Chengdu China department of Statistics and Finance University of Science and Technology of China Hefei China

This paper obtains the uniform estimate for maximum of sums of independent and heavy-tailed random variables with nonnegative random weights, which can be arbitrarily dependent of each other. Then the applications to ... 详细信息

关键词： dependent stochastic return, discount factor, heavy-tails, discrete time insurance risk model, maxima of randomly weighted sums, ruin probability, tail probabilities, uniformly asymptotic estimate.

Sensitive biosensing strategy based on functional nanomaterials

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science china Chemistry 2011年第8期54卷 1202-1217页

作者： JU HuangXian State Key Laboratory of Analytical Chemistry for Life science department of Chemistry, {2. university, {2. 2.0093, china State Key Laboratory of Analytical Chemistry for Life science department of Chemistry Nanjing University Nanjing China

The first decade of the 2.st century has been labeled as "the sensing decade". The functional nanomaterials offer excellent platforms for fabrication of sensitive biosensing devices, including optical and electronic biosensors. A lot of works have fo- cused on the biofunctionalization of different nanomaterials, such as metal nanoparticles, semiconductor nanoparticles and carbon nanostructures, by physical adsorption, electrostatic binding, specific recognition or covalent coupling. These biofunc- tionalized nanomaterials can be used as catalysts, electronic conductors, optical emitters, carriers or tracers to obtain the ampli- fied detection signal and the stabilized recognition probes or biosensing interface. The designed signal amplification strategies have greatly promoted the development of stable, specific, selective and sensitive biosensors in different fields. This review in- troduces some novel principles and detection strategies in the area of biosensing, based on functional nanomaterials. The gen- eral methods for biofunctionalization of nanomaterials with biomolecules and their biosensing application in immunoassay of protein, DNA detection, carbohydrate analysis and cytosensing are also described.

关键词： nanobiosensing biosensors nanomaterials biofunctionalization signal amplification bioanalysis biological recognition

The feasibility analysis of the application of TPV system in reentry

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science china(Technological sciences) 2010年第12期53卷 3310-3315页

作者： YE Hong & GENG Xue department of Thermal science and Energy {2., university of science and Technology of china, Hefei 2.002., china department of Thermal science and Energy {2. University of Science and Technology of China Hefei China

A fundamental design of using thermophotovoltaic (TPV) system to convert the huge aerodynamic heat into electricity during the reentry process was described. The influences of heat conducting way, spectral filter and selective radiating surface on the system performance were analyzed in detail. The results showed that as a thermal conducting component, SiC is better than ablation material, with more electricity output but a larger cooling load, and that the adoption of spectral filter and selective radiating surface could lower the power output to some extent, yet diminish the cooling load prominently.

关键词： TPV reentry process spectral filter selective radiating surface