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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 {2. and engineering,nanjing University of {2. and Technology,nanjing 2.0094,china 2.College of materials {2. and engineering,Southeast University,nanjing 2.1189,china department of materials {2. and engineering Nanjing University of Science and Technology Nanjing China College of materials science and {2. 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,{2., china 2.National Laboratory of Solid Sate Microstructures, nanjing University,{2., china 3 department of materials science and engineering, nanjing University,{2., china department of Physics Nanjing University Nanjing China National Laboratory of Solid Sate Microstructures Nanjing University Nanjing China department of materials {2. 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

Synthesis and Lubrication of Phosphorylcholine Derivative

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Journal of Bionic engineering 2010年第3期7卷 254-258页

作者： Zhenliang Qiao~1, Dangsheng Xiong~1, Lude Lu~2. Pengju Jiang~2.1. department of materials {2. and engineering, nanjing University of {2. and Technology, nanjing 2.0094, P.R. china 2. School of Chemical engineering, nanjing University of {2. and Technology, nanjing 2.0094, P. R. china department of materials {2. and engineering Nanjing University of Science and Technology Nanjing P.R. China School of Chemical engineering Nanjing University of Science and Technology Nanjing P. R. China

The monomer of phosphorylcholine derivative, O-(5-（2.methacryloxy）-3, 3-dimethyl-3-azapentyl)-O’-（ω-hydroxy-octyl）-phosphatequaternary ammonium salt, was designed and synthesized successfully. It was characterized by the spectra ofHNMR and Mass spectra （ESI+）, and every signal was assigned. Then the lubricating characteristics of the phosphorylcholinederivative were investigated on the tribological setup of ball-oh-flat. The Ultra-High Molecular Weight Polyethylene（UHMWPE） flat was rotated against a stainless steel ball with 6 mm diameter. The load was 2.3 N, which corresponded to amaximal Hertz contact pressure of 2. MPa. Water, phosphorylcholine derivative, and Acrylic Acid （AA） solution were used aslubricants, respectively. Compared with AA, the phosphorylcholine derivative shows significant lubrication. It can be stronglyhydrated under water due to the charged segment in chemical structure. The thick water layers within the chains serves asboundary lubricants, and this is thought to be the molecular origins of lubricating behavior.

关键词： artificial joint articular cartilage molecular lubrication mechanism phosphorylcholine synthesis UHMWPE

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 {2. & 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

Tribological Properties of Dimpled Surface Alloying Layer on Carbon Steel

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Journal of Wuhan University of Technology(materials science) 2009年第2期24卷 218-222页

作者：万轶 department of materials {2. & engineering Nanjing University of Science and Technology department of Mechanical and Electrical engineering Yingtian College

The effect of surface structure and coating on tribological properties of 45^# carbon steel disc was analyzed. A Nd：YAG laser was used to generate rnicrodirnples on steel surfaces. Dimples with diameter of 150 rn and depth of 50 rn were distributed in an orbicular array on disc surface. Then the alloying element Mo was sputtered to 45# carbon steel disc surface by means of double glow plasma technology. Diffusion Mo alloying layer with 30min thickness and high hardness up to 0.02. was formed on the disc surface. Tribological experiments of three types samples （smooth, texturing and texturing＋alloying） were conducted with a pin-on-disc tribometer. It is found that the dimpled-samples are most effective for reducing friction in comparison with smooth steel surthces, improving the lubricating state from boundary to hydrodynamic region.

关键词： laser surface texturing double glow plasma surface alloying technology carbon steel tribological performance lubricating state

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science china Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. department of Chemistry, nanjing University of {2. and Technology, nanjing 2.0094, china 2. Institute of Chemical materials, china Academy of engineering Physics, Mianyang 62.900, china department of Chemistry Nanjing University of Science and Technology Nanjing China Institute of Chemical materials China Academy of Engineering Physics Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

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 {2., 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 2. 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.

A new sequential learning algorithm for RBF neural networks

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science china(Technological sciences) 2004年第4期47卷 447-460页

作者： YANG Ge1, LV Jianhong1 & LIU Zhiyuan2.1. department of Power engineering, Southeast University, {2. 2.0096, china 2. department of Power engineering, {2. Institute of Technology, {2. 2.0013, china department of Power engineering Southeast University Nanjing China department of Power engineering Nanjing Institute of Technology Nanjing China

Due to their inherent imperfections, it is hard to use the static neural networks for nonlinear time-varying process modeling and prediction, and the minimal resource allocation network (MRAN) is difficult to be realized for its too many regulation parameters. A new sequential learning algorithm for radial basis function (RBF) neural networks based on local projection named Local Projection Network (LPN) is proposed in this paper. The results of validation for several benchmark problems with the new algorithm show that the presented LPN not only has the same level as M-RAN in network size and precision of the outputs, but also has fewer regulation parameters and is more predictable.

关键词： radial basis functions, local projection network, minimal resource allocation network, learning algorithm.

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 {2.,College of Chemistry & Chemical {2.,nanjing University,nanjing 2.0093,china 2.ational Laboratory of Solid State Microstructure,department of Material science and {2.,nanjing University,nanjing 2.0093,china 3Key Laboratory of Analytical Chemistry for Life science,Ministry of Education,School of Chemistry and Chemical {2.,nanjing University,nanjing 2.0093,china Laboratory of Mesoscopic Chemistry and department of Polymer science and {2. 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

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 {2., Southeast University, nanjing 2.0018, 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 0.02.%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