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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 856-863页

作者： CAI Xin1,2,LIU JinSong1 & WANG ShengLie1 1 wuhan National Laboratory for Optoelectronics,school of Optoelectronic science and Engineering,Huazhong university of science and technology,wuhan 430074,china 2 school of science,wuhan university of technology,wuhan 430070,china wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Technology Wuhan China school of science Wuhan University of Technology Wuhan China

The transverse effects of two Gauss waves mixing in a photovoltaic photorefractive crystal,i.e.,the dynamical evolutions of signal beam with different parameters,are traced numerically and *** the one-dimensional numerical simulations and two-dimensional experimental investigations show that the self-focusing effect of signal beam becomes more obvious as the intensity of pump beam and the angle between the signal and pump beams *** accordance with these results,the state of two Gaussian waves mixing is controllable.

关键词： numerical simulation experimental investigation two-wave mixing transverse effects Gaussian distribution

Piezoresistivity of Carbon Fiber Graphite Cement-based Composites with CCCW

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Journal of wuhan university of technology(Materials science) 2011年第2期26卷 340-344页

作者：范晓明 school of Materials science and Engineering Wuhan University of Technology

The electrical conductivity and piezoresistivity of carbon fiber graphite cement-matrix composites（CFGCC） with carbon fiber content（1% by the weight of cement）,graphite powder contents （0%-50% by the weight of cement） and CCCW（cementitious capillary crystalline waterproofing materials,4% by the weight of cement） were *** experimental results showed that the relationship between the resistivity of CFGCC and the concentration of graphite powders had typical features of percolation *** percolation threshold was about 20%.A clear piezoresistive effect was observed in CFGCC with 1wt% of carbon fibers,20wt% or 30wt% of graphite powders under uniaxial compressive tests,indicating that this type of smart composites was a promising candidate for strain *** measured gage factor （defined as the fractional change in resistance per unit strain） of CFGCC with graphite content of 20wt% and 30wt% were 37 and 22,*** the addition of CCCW,the mechanical properties of CFGCC were improved,which benefited CFGCC piezoresistivity of stability.

关键词： carbon fiber graphite cement-based composites cementitious capillary crystalline waterproofing materials electrical resistivity piezoresistivity

Binding Materials of Dehydrated Phases of Waste Hardened Cement Paste and Pozzolanic Admixture

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Journal of wuhan university of technology(Materials science) 2009年第1期24卷 140-144页

作者：吕林女 school of science Wuhan University of Technology

Fly ash （FA） and ground granulated blast-furnace slag （GGBFS） were added to improve the performances of regenerated binding materials （RBM） which refer to dehydrated phases with rebinding ability of waste hardened cement paste. Flowability tests, compressive strength tests, SEM, TG-DSC, and non-evaporable water content tests were employed to study the performances of the combined binding materials and the interactions between RBM, FA, and GGBFS. Results show that adding FA or GGBFS can improve the workability of RBM paste, and GGBFS has positive effects on strength of RBM. Pozzolanic reactions happen between RBM, FA, and GGBFS. And the activation effect of RBM to FA and GGBFS is superior to that of P.O grade-32.5 cement, especially at earlier ages, because of the high reactive f-CaO existing in RBM. On the advantages of the synergetic effects of RBM and pozzolanic admixtures such as FA and GGBFS, new combined binding materials can be prepared by blending them together.

关键词： combined binding materials dehydrated phase fly ash granulatedblast-furnace slag

Determination of the Thermal Expansion Coefficient of Concrete at Early Ages by Using Temperature-stress Testing Machine

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Journal of wuhan university of technology(Materials science) 2006年第4期21卷 146-149页

作者：霍凯成 Hubei Key Laboratory of Roadway Bridge & Structure Engineering Wuhan University of TechnologyWuhan 430070China

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved ： temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolation process should be taken into consideration in the same time. Proper chemical admixtures and mineral cornpasitions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

关键词： concrete coefficient of thermal expansion temperature-stress test

Phenomenon of “contact guidance” on the surface with nano-micro-groove-like pattern and cell physiological effects

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Chinese science Bulletin 2009年第18期54卷 3200-3205页

作者： ZHOU Feng 1,2, YUAN Lin 1,3, HUANG He 1,2 & CHEN Hong1,2 1 State Key Laboratory of Advanced technology for Materials Synthesis and Processing, wuhan 430070, china 2 school of Materials science and Engineering, wuhan university of technology, wuhan 430070, china 3 Biomedical Materials Research Center, wuhan university of technology, wuhan 430070, china State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan China school of Materials science and Engineering Wuhan University of Technology Wuhan China Biomedical Materials Research Center Wuhan University of Technology Wuhan China

The topography of material surface has important influence on cell behavior and physiological functions. Groove-like pattern has drawn much attention among various patterns, due to the phenomenon of "contact guidance" induced by this kind of topography. This review mainly focuses on "contact guidance" formation as well as its influence on cell behavior and physiological effects. The possible mechanisms of "contact guidance" formation were discussed. The research trend and the potential applications were also suggested.

关键词：细胞行为生理功能材料表面逻辑效应触指纳米微米生理效应

Sandwich Magnetoelectric Composites of Polyvinylidene Fluoride,Tb-Dy-Fe Alloy,and Lead Zireonate Titanate

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Journal of wuhan university of technology(Materials science) 2007年第4期22卷 596-599页

作者：赵广辉熊传溪 State Key Laboratory of Advanced technology for Materials Synthesis and Processing school of Computer science and technology Wuhan University of TechnologyWuhan 430070China school of Materials science and Engineering Wuhan University of TechnologyWuhan 430070China

The novel sandwich composites were prepared by sandwiching a polyvinylidene fluoride/Tb- Dy-Fe alloy composite （PVDF/Terfenol-D） between polyvinylidene fluoride/lead zirconate titanate composites （PVDF/PZT）. The maximum magnetoelectric effect voltage coefficient, （dE/dn）33max, of the sandwich composites is higher than that of three-phase composites at their own optimal loading level of Terfenol-D. This is attributed to less interface relaxations of strain and better polarization of the sandwich composites. When the volume fraction of Terfenol-D is higher than 0.10, no coupling interaction for three-phase composites could be observed, but （dE/dn）33max of sandwiched composites still reached 20 mV/（***）. At high magnetic field intensity, the magnetoelectric effect voltage coefficient, （dE/dn）33, of sandwich composites is higher than that of three-phase composites; at low magnetic field intensity, （dE/dn）33 of sandwich composites is lower than that of three-phase composites. At their resonance frequency, the （dE/dn）33max of the sandwich composites and the three phase composites are 150 mV/（***） and 42 mV/（cmoOe）, respectively. This significant increase of （dE/ dn）33max at resonance frequency confirms the improvement of maximum magnetoelectric effect coefficient via sandwich-structured composites.

关键词： magnetoelectric piezoelectric sandwiched composites

Synthesis, Characterization and Flame-retardant Properties of Epoxy Resins and AACHH Composites

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Journal of wuhan university of technology(Materials science) 2009年第5期24卷 763-767页

作者：秦麟卿 State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology

Flame retardant epoxy resins were prepared by a simple mixed method using ammonium aluminum carbonate hydroxy hydrate （AACHH） as a halogen-free flame retardant. The prepared samples were characterized by X-ray diffraction, thermogravimetric and differential scanning calorimetry, scanning electron microscope and limiting oxygen index（LOI） experiments. Effects of AACHH content on LOI of epoxy resins/AACHH composite and flame retardant mechanism were investigated and discussed. Results show that AACHH exhibites excellent flame-retardant properties in epoxy resin（EP）. When the content of AACHH was 47.4%, the LOI of EP reached 32.2%. Moreover, the initial and terminal decomposition temperature of EP increased by 48 ℃ and 40 ℃, respectively. The flame retarded mechanism of AACHH is due to the synergic flame retardant effects of diluting, cooling, decomposition resisting and obstructing.

关键词： epoxy resin(EP) flame retardant ammonium aluminum carbonate hydroxy hydrate (AACHH) composite

Electrically Conductive Concrete for Heating Using Steel Bars as Electrodes

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Journal of wuhan university of technology(Materials science) 2010年第3期25卷 523-526页

作者：侯作富 school of Mechanical Engineering Yangtze University

The steel bars with good electrical conductivity were used as two kinds of electrodes in the making of carbon fiber（CF） electrically conductive concrete for *** results of the pertinent experiments illustrate the design is *** change in electrical resistivity over three years＇ hydration time was studied when steel bars were used as lateral face electrodes and top bottom surface electrodes *** temperature rise test was conducted to verify the heating properties of two kinds of *** only the study can reduce the CF volume content of electrically conductive concrete for heating to 0.58% or 0.36% according to different design,but also it will enhance the carrying capacity of the concrete roadway for heating.

关键词： steel bar carbon fiber electrical resistivity temperature rise

Magnesia Modification of Alkali-Activated Slag Fly Ash Cement

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Journal of wuhan university of technology(Materials science) 2011年第1期26卷 121-125页

作者：沈卫国 Key Laboratory of Silicate Materials science and Engineering of Ministry of Education Wuhan University of Technology school of Materials science and Engineering Wuhan University of Technology

A new type of magnesia modification alkali-activated cement was prepared, the strength, setting time, shrinkage ratio and cracking behavior, as well as the composition and structure of the hydration product were investigated. The results indicate that the setting time of this cement is similar to that of the ordinary commercial cements; its strength reaches the standard of 42.5 degree cement, its cracking resistance has been remarkably improved because of the micro-aggregate effect of fly ash and shrinkage compensating of magnesia.

关键词： alkali-activated cement crack magnesia volume stability hydration

Early Age Hydration of Cement Paste Monitored with Ultrasonic Velocity and Numerical Simulation

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Journal of wuhan university of technology(Materials science) 2010年第4期25卷 704-707页

作者：陈伟 Key Laboratory of Silicate Materials science and Engineering Ministry of EducationWuhan University of Technology school of Materials science and Engineering Wuhan University of Technology

Early age hydration of cement paste was investigated by monitoring the ultrasonic propagation velocity and simulated with the numerical model CEMHYD3D. The ultrasonic velocity of the P-wave was recorded during the first 24 hours of the hydration process and its evolution was analyzed. It is shown that the UPV method is an effective, accurate and non-destructive method for monitoring the early age hydration process of cement paste. The early age hydration process can be classified as four periods, which are the dormant period, acceleration period, deceleration period and stabilization period. Higher w/c ratios result in lower UPV, and delay initial setting time due to the decreased solid volume. The change of UPV is clearly related to the hydration degree of cement particles.

关键词： early age hydration ultrasonic velocity hydration degree CEMHYD3D