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Dynamic Mechanical and Thermal Properties of Cross-linked Polystyrene/Glass Fiber Composites

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Journal of wuhan {1. of {2.(Materials science) 2010年第5期25卷 780-784页

作者：朱泉峣陈文 School of Materials science and Engineering Wuhan University of Technology State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology

Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene （CLPS） as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysilane （VTES）, vinyl trimethoxysilane （VTMS） and γ-methacryloylpropyl trimethoxysilane （MPS）. The treated glass fibers were analyzed by fourier transform infrared spectroscopy （FTIR）. Dynamic mechanical thermal analysis （DMTA） and thermo-gravimetric analysis （TGA） were employed to investigate the effect of glass fibers surface modification on viscoelastic behavior and thermal properties. The morphology of fracture surfaces of various composites was observed by scanning electron microscopy （SEM）. The results revealed that these coupling agents were connected to the surfaces of the fibers by chemical bonding. Dynamic mechanical properties as well as thermal stability of the composites were improved considerablely, but to varying degrees depending on the fiber modification. The diversities of improvement of properties were attributed to the different interfacial adhesion between CLPS matrix and the glass fibers.

关键词： polymer-matrix composite cross-linked polystyrene (CLPS) fiber/matrix bond dynamic mechanical thermal analysis.

A Hybrid Genetic Algorithm for Reduct of Attributes in Decision System Based on Rough Set Theory

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wuhan {1. Journal of Natural {2.s 2002年第3期7卷 285-289页

作者： Dai Jian\|hua 1,2., Li Yuan\|xiang 1,2.,Liu Qun 3 1. State Key Laboratory of Software Engineering, wuhan {1., wuhan 430072. hubei,china 2. School of Computer, wuhan {1., wuhan 430072. hubei, china 3. School of Computer {1.}, wuhan {1. State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Chongqing university of Posts & Telecommunications School of Computer Science Chongqing China (GRID:grid.411587.e) (ISNI:***)

Knowledge reduction is an important issue when dealing with huge amounts of data. And it has been proved that computing the minimal reduct of decision system is NP-complete. By introducing heuristic information into genetic algorithm, we proposed a heuristic genetic algorithm. In the genetic algorithm, we constructed a new operator to maintaining the classification ability. The experiment shows that our algorithm is efficient and effective for minimal reduct, even for the special example that the simple heuristic algorithm can’t get the right result.

关键词： rough set reduction genetic algorithm heuristic algorithm

On the Symmetry Classes of Functions

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wuhan {1. Journal of Natural {2.s 2005年第5期10卷 813-816页

作者： ZHU Ping~1.2. FAN Yun~3 1. School of Mathematics and Statistics, {2. {1., {2. 430072. hubei, china 2. School of science, Beijing {1. of Posts and Telecommunications, Beijing 1.0876, china 3. School of Mathematics and Statistics, Huazhong Normal {1., {2. 430079, hubei, china wuhan {1. School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Beijing university of Posts and Telecommunications School of Science Beijing China (GRID:grid.31880.32) Huazhong Normal university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.411407.7) (ISNI:***)

Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several variables is a symmetry class, where ξi is any block character. Then we present a relationship among certain operators introduced for block character. Then we present a relationship among certain operators introduced for block characters. As a consequence, we obtain a decomposition of an arbitrary R-valued function of several variables. Finally, we describe the symmetry property of such summands and determine all the symmetry classes.

关键词： symmetry class strict symmetry class blockcharacter ξi-symmetric function block idempotent

Toughening Modification of Unsaturated Polyester Resin Using HDI Trimer

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Journal of wuhan {1. of {2.(Materials science) 2009年第4期24卷 627-630页

作者：段华军 School of Materials science and Engineering Wuhan University of Technology

HDI trimer was firstly used to improve the mechanical properties of hydroxyl-terminated unsaturated polyester （UP）. Mechanical properties measurements performed on the cured materials demonstrate a distinct improvement in intensity and toughness in the presence of HDI trimer and shows the change trends of increase and then decrease. The morphological analysis of the fracture surfaces shows that the micro-phase separated structures appear in modified UPR systems and changed from dendritric, dimple and to cystiform structures with the increase of HDI trimer content. The presence of the cystiform structures made the modified UPR systems present the best properties.

关键词： HDI trimer unsaturated polyester toughness mechanical properties morphology

Mathematical Model of the Identical Slope Surface

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wuhan {1. Journal of Natural {2.s 2002年第1期7卷 54-58页

作者： Hu Jian-guo 1. Chen yue-ping 2.1. School of Urban Studies,{2. {1.,{2. 430072. hubei, china 2.College of Politics and Administration,{2. {1., {2. 430072.hubei, china wuhan {1. School of Urban Studies Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. College of Politics and Administration Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The formation of the identical slope surface and the method of construction are discussed. On the basement of building the parameter equation of variable-radius circle family envelope, the frequently used parameter equation of the identical slope surface of the top of taper moving along column helix, horizental arc and line is built. The equation can be used to construct the identical slope surface’s contours, gradient lines and three dimensional figures correctly.

关键词： Key words identical slope surface family of circles mathematical model envelope elevation projection contours

A mathematical model for solid liquid and mass transfer coupling and numerical simulation for hydraulic fracture in rock salt

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Progress in Natural science:Materials International 2005年第8期15卷 742-748页

作者： LIANG Weiguo 1.2. and ZHAO Yangsheng1.1. Mining technology Institute, Taiyuan {1. of technology, Taiyuan 03002., china 2. Rock and Soil Mechanics Institute, Chinese Academy of sciences, wuhan 430071. china) Mining technology Institute Taiyuan University of Technology Taiyuan 030024 China. Rock and Soil Mechanics Institute Chinese Academy of Sciences Wuhan 43007! China

The hydraulic fracture in rock salt is a complicated solid fluid and mass transfer coupling process. Through theoretical analysis, a solid fluid and mass transfer coupling mathematical model of hydraulic fracture in rock salt is established in this work, and numerical simulations are carried out with the model. The simulation results indicate that rock salt cracks in the typical way of wing-crack(or tensile crack) during the fracture, and the relation of fracture aperture (w) with expanding distance (x) and fracture time (t) is w=(0.0034+0.0006t)e (0.0007+0.001.t)x. Furthermore, it has been found that both the water pressure in the crack and the expanding velocity of the crack decrease gradually as a result of the influence of salt dissolving during fracturing. These numerical simulations well illustrate the process of hydraulic fracture in rock salt and are significantly meaningful in engineering practice.

关键词： rock salt hydraulic fracture solid liquid and mass transfer coupling mathematical model numerical simulation.

Flexural-tensile Properties of Layered Steel Fiber Reinforced Rubber Concrete

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Journal of wuhan {1. of {2.(Materials science) 2009年第5期24卷 846-848页

作者：易贤仁 School of sciences Wuhan University of Technology

Layered steel fiber reinforced rubber concrete （LSFRRC）, a new type of pavement concrete based on the requirements of national standard were experimentally researched. The different properties of flexural-tensile strength from plain concrete （PC）, rubber concrete （RC）, layered steel fiber reinforced concrete （LSFRC） and LSFRRC were presented. Experimental results show that the tensile strength of LSFRRC is improved by 4.1.% compared with PC, by 1..75% compared with RC. The load-deflection curve on flexural-tensile propertiesis put forward. The flexural-tensile toughness index I1. of LSFRRC is improved 1..32.times compared with PC.

关键词： RC LSFRRC flexural-tensile strength load-deflection curve experimental re-search

Photocatalytic Degradation of Metronidazole in Aqueous Solution by Niobate K_6Nb_(1..8)O_(30)

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wuhan {1. Journal of Natural {2.s 2010年第4期15卷 345-349页

作者： wang Huiyan1. ZHANG Gaoke2. GAO Yuanyuan2.1. Hospital, {1. {2. of technology, {1. 430070, hubei, china 2. School of Resources and Environmental Engineering, {1. {2. of technology, {1. 430070, hubei, china Hospital Wuhan University of Technology Wuhan Hubei China School of Resources and Environmental Engineering Wuhan University of Technology Wuhan Hubei China

The photocatalytic degradation of antibiotic metroni-dazole in aqueous solution by niobate K6Nb1..8O30 photocatalyst that was prepared using a soft-chemical method was studied by Fourier transform infrared spectroscopy and UV-Vis absorption spectrum. Metronidazole is very stable and is difficult to degrade under UV irradiation. K6Nb1..8O30 photocatalyst cannot degrade metronidazole without UV irradiation and shows very high photo-catalytic activity for the degradation of metronidazole under UV irradiation. The photocatalytic degradation rate of metronidazole increased with increasing the dosage of K6Nb1..8O30 photocatalyst. The photocatalytic degradation reaction of metronidazole by nio-bate K6Nb1..8O30 follows the first-order kinetic equation.

关键词： niobate potassium niobate metronidazole photo- catalytic kinetics

Effect of Tin on the Reaction Synthesis of Ternary Carbide Ti_3AlC_2

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Journal of wuhan {1. of {2.(Materials science) 2009年第2期24卷 283-286页

作者：周卫兵 School of Materials science and Engineering Wuhan University of Technology

The effect of tin on synthesis of Ti3AlC2.by spark plasma sintering （SPS） from TiC/Ti/Al powders was investigated. X-ray diffraction （XRD） and scanning electron microscopy （SEM） were used for phase identification and microstructure evaluation. The experimental results show that addition of tin can considerably accelerate the synthesis reaction of Ti3AlC2.and fully dense, essentially single-phase polycrystalline Ti3AlC2.could be successfully obtained by sintering 2.iC/1.i/1.l/0.2.n powders at 1.00-1.50 ℃ under a pressure of 30 MPa. SEM images show that Ti3AlC2.samples in about 2.5 μm thick and 1.-2.μm long platelets can be obtained. The fracture toughness and flexural strength of Ti3AlC2.were 6.5±0.2.MPa·m^1.2.and 560±1. MPa, respectively.

关键词： titanium aluminum carbide spark sintering technique synthesis