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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 department of materials science and engineering Nanjing University of Science and Technology Nanjing China College of materials science and engineering Southeast University Nanjing 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

Study on the thermal stability and electrical properties of the high-k dielectrics (ZrO_2) _x(SiO_2)_(1-x)

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science china(Technological sciences) 2009年第8期52卷 2222-2226页

作者： Lü ShiCheng1,2, YIN Jiang1,2, XIA YiDong2,3, GAO LiGang2,3 & LIU ZhiGuo2,3 1 department of Physics, nanjing university, nanjing 2.0093. china 2 National Laboratory of Solid Sate Microstructures, nanjing university, nanjing 2.0093. china 3 department of materials science and engineering, nanjing university, nanjing 2.0093. china department of Physics Nanjing University Nanjing China National Laboratory of Solid Sate Microstructures Nanjing University Nanjing China department of materials science and engineering Nanjing University Nanjing China

(ZrO2)x(SiO2)1-x (Zr-Si-O) films with different compositions were deposited on p-Si(100) substrates by using pulsed laser deposition technique. X-ray photoelectron spectra (XPS) showed that these films remained amorphous after annealing at 800℃ with RTA process in N2 for 60 s. The XPS spectra indi- cated that Zr-Si-O films with x=0.5 suffered no obvious phase separation after annealing at 800℃, and no interface layer was formed between Zr-Si-O film and Si substrate. While Zr-Si-O films with x >0.5 suffered phase separation to precipitate ZrO2 after annealing under the same condition, and SiO2 was formed at the interface. To get a good interface between Zr-Si-O films and Si substrate, Zr-Si-O films with bi-layer structure (ZrO2)0.7(SiO2)0.3/(ZrO2)0.5(SiO2)0.5/Si was deposited. The electrical properties showed that the bi-layer Zr-Si-O film is of the lowest equivalent oxide thickness and good interface with Si substrate.

关键词： high-k dielectric film pulsed laser deposition pseudo ternary alloy

Quantitativ　estructure－activity　relationships　for　studying　alkyl（1－phenylsulfonyl）　cycloalkane－carboxylates

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Journal of Environmental sciences 1996年第2期8卷 157-166页

作者： He Yibing Wang Liansheng (department of Environmental science and engineering, nanjing university, nanjing 2.0093. china) department of Environmental science Nanjing University Nanjing 210093 China

Octanol/water partition coefficients,adsorption coefficients for soils and sediments and acute toxicities to Daphnia magna of 28 alkyl (1-phenylsulfonyl) cycloalkane-carboxylates were measured. These properties were correlated by linear solvation energy relationship (LSER) and chromatographic retention data determined by reverse-phase high performance liquid chromatography (RP-HPLC). The accuracy and range of applicability of these two quantitative structure-activity relationship (QSAR) methods were compared in this paper.

关键词： alkyl (1-phenylsulfonyl) cycloalkane-carboxylates LSER R-PHPLC.

Massive Si Phase and Its Growth Mechanism in Al-Si Casting Alloy

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Journal of materials science & Technology 2004年第5期20卷 589-591页

作者： Hengcheng LIAO and Guoxiong SUNDepaxtment of materials science and engineering, Southeast university, nanjing 210018, china Dept. of Mat. Sci. and Eng. Southeast Univ. Nanjing 210018 China

Optical microscope and scanning electron microscope were used to observe the microstructure of the AI-11.6%Si and AI-11.6%Si-0.4%Mg alloys and the morphology of the massive silicon particles. It is found that the massive silicon phase, observed in the unfully modified alloys with 0.010%Sr, disappears completely in the alloys fully modified with 0.020%Sr. The serrations and reentrant edges shown in the massive silicon particles with the conventional casting indicate that the TPRE mechanism plays an important role in the growth of the massive silicon phase. The ripples and steps suggest that the "lateral microscopic growth" may be another operating mechanism.

关键词： Al-Si alloy Massive silicon Microstructure Growth mechanism

TENSILE　PROPERTIES　AND　CREEP　RESISTANCE　OF　Fe_3Al－BASED　ALLOYS　CONTAINING　NIOBIUM

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 135-139页

作者： ZHANG Zhonghua SUN Yangshan GUO Jun(department of materials science and engineering, Southeast university, nanjing 210096,china) Southeast Univ Nanjing China

Small amount(0.5-0.8at.%) of niobium addition to the multicomponent alloys based on Fe3Al(Fe-28Al-5Cr-0.5Mo-0.05Zr-0.05B-0.1Ce) results in the microstructural refinement and the increase in the yield strength at temperatures up to 600℃,but is not beneficial to room temperature *** of microanalysis indicate that the addition of niobium causes the formation of precipitates with complex compositions which strengthen both matrix and grain boundaries and enhance the creep resistance of the alloys.

关键词： Fe_3Al,Nb,tensile property creep

Dynamic Mechanical Behaviour of Ultra-high Performance Fiber Reinforced Concretes

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

作者：赖建中 department of materials science & engineering 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

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 engineering, nanjing university of science and Technology, nanjing 210094, P. R. china department of materials science and engineering 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-200)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

Polymer-assisted nanoparticulate contrast-enhancing materials

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science china Chemistry 2010年第3期53卷 479-486页

作者： DING Yin1,3,HU Yong2,WU Wei1 & JIANG XiQun1 1Laboratory of Mesoscopic Chemistry and department of Polymer science and engineering,College of Chemistry & Chemical engineering,nanjing university,nanjing 2.0093.china 2National Laboratory of Solid State Microstructure,department of Material science and engineering,nanjing university,nanjing 2.0093.china 3Key Laboratory of Analytical Chemistry for Life science,Ministry of Education,School of Chemistry and Chemical engineering,nanjing university,nanjing 2.0093.china Laboratory of Mesoscopic Chemistry and department of Polymer science and engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing China Key Laboratory of Analytical Chemistry for Life science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing China National Laboratory of Solid State Microstructure Department of Material Science and Engineering Nanjing University Nanjing China

The application of nanotechnology in medicine research has significant potential in modern biomedical research,disease diagnosis and *** fluorophore-based detection techniques have been widely used as imaging and signal transduction tools for the detection of trace levels of *** photosensitivity of the fluorophores,however,limits their application in such complex environments as living bio-systems where degradation or photobleaching *** nanoparticles have unique and stable optical,electrical,magnetic and catalytic properties because of their various shapes,sizes and *** potential of the nanoparticles as novel imaging agents has been studied as a possible solution to this *** modification of inorganic nanoparticles could enhance their biostability in physiological conditions and ability of targeting bioactive molecules.

关键词： contrast agent cell image gold nanoparticles iron oxide nanoparticles carbon nanotubes polymeric-inorganic hybrid nanoparticles

L-R smash products for bimodule algebras

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Progress in Natural science:materials International 2006年第6期16卷 580-587页

作者： ZHANG Liangyun (department of Mathematics, nanjing Agricultural university, nanjing 210095, china department of Mathematics, nanjing university, nanjing 210008, china) department of Mathematics Nanjing Agricultural University Nanjing 210095 China department of Mathematics Nanjing U-niversity Nanjing 210008 China

In this paper, we prove that the L-R smash product A(?)H is exactly the twisted smash product A * H if H is a finite dimensional cocommutative Hopf algebra, and give a sufficient and necessary condition for L-R smash products to be bialgebras (Hopf algebras) . For any finite dimensional coquasitriangular Hopf algebra (H,σ), we prove that the L-R smash product H(?)H is semisimple Artinian if H is semisimple and H * is unimodular. In particular, the L-R smash product D(H)* (?)D(H)* semisimple Artinian if the Drin-fel'd double D(H) is semisimple.

关键词： bimodule algebras L-R smash products coquasitriangular Hopf algebras Long bialgebras.

MEASUREMENT OF NUMBER AVERAGE MOLECULAR WEIGHT OF STYRENE OLIGOMER BY ^(13)C-NMR METHOD

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Chinese Journal of Polymer science 1999年第2期17卷 135-140页

作者： Song Wang Xiao-hu Yan Rong-shi Cheng department of Polymer science and engineering, nanjing university, nanjing 2.0093. china department of Polymer science and engineering Nanjing University Nanjing 210093 China

^(13)C-NMR ~1H-decoupled spectra of styrene polymers were assigned by comparison with modelcompounds, then used in measurements of number average molecular weights. The higher limit of an exactdetermination of the end group signal is less than a molecular weight of 10~4. For polymer samples withM_n3, the results obtained from ^(13)C-NMR spectra of saturated carbon region are in excellent agreementwith the values determined by ~1H-NMR, SEC, and VPO methods, while the results from ^(13)C-NMR spectra ofphenyl C-1 carbon region are somewhat higher than the values determined by other methods.

关键词： Molecular weight measurement Styrene oligomer ^(13)C-NMR spectra