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china Foundry 2024年第1期21卷 11-19页

作者： Wen-ning Liu Wei Zhang Peng-yue Wang Yi-xian Liu Xiang-yi jiao Ao-xiang Wan Cheng-gang Wang Guo-dong tong Shou-mei Xiong school of Materials Science and engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084Beijing china FAW Group Co. Ltd.Changchun 130013China china FAW Foundry Co. Ltd.Changchun 130013China

The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron microscopy(SEM)and laboratory computed tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when compared to the AlSi10MnMg *** AlSi9MnMoV alloy,which was designed with trace multicomponent additions,displays a notable grain refining effect in comparison to the AlSi10MnMg *** elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-*** a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and *** an increase in slow shot speed,the size and number of ESCs and porosities significantly *** addition,the distribution of ESCs is more dispersed and the net-shrinkage *** tensile property is greatly improved by adopting a higher slow shot *** ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%).

关键词： hypoeutectic Al-Si alloy high pressure die casting porosity externally solidified crystal tensile property

On the 8th-order Drag Coefficient Formula of a Sphere in a Uniform Stream: a Simplified Discription

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Communications in Nonlinear Science and Numerical Simulation 1998年第4期3卷 256-260页

作者： Shjun LIAO (school of Naval Architecture & Ocean engineeringshanghai jiao tong university,shanghai 200030, china)E-mail: sjliao@*** school of Naval Architecture & Ocean engineering shanghai jiaotong university Shanghai 200030 China

We verify from both physical and mathematical view-points that the viscons drag coefficient formulas of a sphere in a uniform stream should be an odd function of Reynolds number. Therefore, the famous Oseen’s (1910) drag coefficient formula CD for a sphere would seem to be wrong even qualitatively. Besides,we propose up-to 8th-order drag coefficient formulas by means of the homotopy analysis method, a new analytic technique developed by the author. Moreover, all of our up-to8th-Order drag coefficient formulas are odd functions of Reynolds nUmber and agree better with experimental data in a larger range of Reynolds number. So, our high-order drag coefficient formulas are better, not only qualitatively but also quantitatively, than those given by Oseen, Goldstein, Proudman and Pearson.

关键词： drag coefficient viscous flow past a sphere uniformly valid analytic approximation

Image stylization with enhanced structure on GPU

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Science china(Information Sciences) 2012年第5期55卷 1093-1105页

作者： LI Ping 1,SUN HanQiu 1,SHENG Bin 1,2 & SHEN JianBing 3 1 Department of Computer Science and engineering,The Chinese university of Hong Kong,Hong Kong,china 2 Department of Computer Science and engineering,shanghai jiao tong university,shanghai 2.02.0,china 3 school of Computer Science and Technology,Beijing Institute of Technology,Beijing 100081,china 1. Department of Computer Science and engineering The Chinese University of Hong Kong Hong Kong China2. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China3. School of Computer Science and Technology Beijing Institute of Technology Beijing 100081 China

This paper presents a graphics processing unit (GPU) based stylization approach that preserves the fine structure between the original and the stylized images using gradient *** abstraction and painterly stylization methods focused on contrast manipulation only,and thus the detailed salient structures of the input images are always destroyed when performing the current stylization techniques because of limitations like unavoidable salience information loss caused by contrast *** propose an image structure map to naturally model the fine structure existing in the original ***-based structure tangent generation and tangent-guided image morphology are used to construct the structure *** image structure map,unlike an edge map,not only systematically models the boundary information within the imagery but also accentuates the underlying inner structure detail for further *** facilitate the final stylization via parallel bilateral grid and structure-aware stylizing optimization on a GPU-CUDA platform in real *** multiple experiments,the proposed method consistently demonstrates efficient and high quality image stylization performance.

关键词： image stylization non-photorealistic rendering real-time processing GPU image abstraction

Bioreducible unimolecular micelles based on amphiphilic multiarm hyperbranched copolymers for triggered drug release

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Science china Chemistry 2010年第12期53卷 2497-2508页

作者： PANG Yan 1,LIU JinYao 1,SU Yue 1,ZHU BangShang 2,HUANG Wei 1,ZHOU YongFeng 1,ZHU XinYuan 1,2 & YAN DeYue 1 1 school of Chemistry and Chemical engineering,State Key Laboratory of Metal Matrix Composites,shanghai jiao tong university,shanghai 2.02.0,china 2 Instrumental Analysis Center,shanghai jiao tong university,shanghai 2.02.0,china 1. school of Chemistry and Chemical engineering State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai 200240 China2. Instrumental Analysis Center Shanghai Jiao Tong University Shanghai 200240 China

A novel type of bioreducible amphiphilic multiarm hyperbranched copolymer (H40-star-PLA-SS-PEG) based on Boltorn H40 core,poly(L-lactide) (PLA) inner-shell,and poly(ethylene glycol) (PEG) outer-shell with disulfide-linkages between the hydrophobic and hydrophilic moieties was developed as unimolecular micelles for controlled drug release triggered by *** obtained H40-star-PLA-SS-PEG was characterized in detail by nuclear magnetic resonance (NMR),Fourier transform infrared (FTIR),gel permeation chromatography (GPC),differential scanning calorimeter (DSC),and thermal gravimetric analysis (TGA).Transmission electron microscopy (TEM) and dynamic light scattering (DLS) analyses suggested that H40-star-PLA-SS-PEG formed stable unimolecular micelles in aqueous solution with an average diameter of 19 ***,these micelles aggregated into large particles rapidly in response to 10 mM dithiothreitol (DTT),most likely due to shedding of the hydrophilic PEG outer-shell through reductive cleavage of the disulfide *** a hydrophobic anticancer model drug,doxorubicin (DOX) was encapsulated into these reductive unimolecular *** vitro release studies revealed that under the reduction-stimulus,the detachment of PEG outer-shell in DOX-loaded micelles resulted in a rapid drug *** cytometry and confocal laser scanning microscopy (CLSM) measurements indicated that these DOX-loaded micelles were easily internalized by living *** tetrazolium (MTT) assay demonstrated a markedly enhanced drug efficacy of DOX-loaded H40-star-PLA-SS-PEG micelles as compared to free *** of these results show that these bioreducible unimolecular micelles are promising carriers for the triggered intracellular delivery of hydrophobic anticancer drugs.

关键词： hyperbranched polymer unimolecular micelle drug delivery

Wear Behavior of Diamond-Coated Drawing Dies

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Transactions of Tianjin university 2011年第4期17卷 259-263页

作者：林子超孙方宏沈彬 school of mechanical engineering Shanghai Jiao Tong University

The failure behavior of diamond-coated die was investigated experimentally and analytically through finite element method (FEM) simulation in the present work. Diamond coatings were fabricated by straight hot filament chemical vapor deposition (CVD) passing through the interior hole of the drawing die using a mixture of hydrogen and acetone as source gases. The performance tests were made under real drawing condition. Scanning electron microscopy (SEM) was used for the study of coating wear after die service. The coating wear appears on two regions of the reduction zone: one is near the entrance where the contact begins, and the other is at the end of the reduction zone. FEM simulation was made for calculating the von Mises stresses distribution on the coating and substrate during the drawing process. The present work was of great practical significance for the improvement of drawing performance of diamond-coated drawing dies.

关键词： wire drawing diamond coating wear FEM simulation

Car-Parinello molecular dynamics simulations of thionitroxide and S-nitrosothiol in the gas phase,methanol,and water——A theoretical study of S-nitrosylation

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中国科学:化学 2012年第10期42卷 1497-1498页

作者： LIANG Juan1,CHENG ShangLi1,HOU JunWei1,XU ZhenHao1,2 & ZHAO Yi-Lei1,2,3* 1 State Key Laboratory of Microbial Metabolism,school of Life Sciences and Biotechnology,shanghai jiao tong university,shanghai 2.02.0,china 2 shanghai Center for Systems Biomedicine,shanghai jiao tong university,shanghai 2.02.0,china 3 MOE Laboratory of Scientific and engineering Computing,shanghai jiao tong university,shanghai 2.02.0,china State Key Laboratory of Microbial Metabolism school of Life Sciences and Biotechnology shanghai jiao tong university shanghai 2.02.0 china shanghai Center for Systems Biomedicine shanghai jiao tong university shanghai 2.02.0 china MOE Laboratory of Scientific and engineering Computing shanghai jiao tong university shanghai 2.02.0 china

A dilemma about whether thionitroxide radical(RSNHO) or S-nitrosothiol(RSNO) is observed in protein S-nitrosylation has arisen *** illustrate the effect of chemical environment on these structures,this paper presents quantum mechanical molecular dynamics of thionitroxide,and cis-and trans-S-nitrosothiols in the gas phase,methanol,and *** using Car-Parrinello molecular dynamics(CPMD),we have observed that there is free rotation about the S-N bond at 300 K in thionitroxide,but no such rotation is observed for *** C-S-N-O torsion angle distribution in thionitroxide is significantly dependent upon the surrounding environment,leading to either gauche-,cis-,or *** the case of S-nitrosothiol the C-S-N-O plane is twisted slightly by 5°-15° in the cis-isomer,while the periplanar structure is well-retained in the *** calculated results are in agreement with the X-ray crystallographic data of small molecular RSNO ***,for both compounds,the CPMD simulations show that solvation can cause a decrease in the S-N bond ***,the oxygen atom of thionitroxide is found to be a good hydrogen-bond acceptor,forming an oxyanion-hole-like hydrogen bonding network.

关键词： quantum mechanical molecular dynamics S-nitrosylation thionitroxide S-nitrosothiol solvent effect

A NUMERICAL STUDY ON SIDE HULL OPTIMIZATION FOR TRIMARAN

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Journal of Hydrodynamics 2011年第2期23卷 265-272页

作者： XU Min ZHANG Shi-lian State Key Laboratory of Ocean engineering Shanghai Jiao Tong University Shanghai 200240 China

Due to the interaction between the main hull and side hulls, different layouts and lengths of side hulls affect the wave loads significantly. Based on three-dimensional potential theory and Green＇s function, this article gives the significant values for wave loads, including vertical shear forces and vertical bending moments at different locations on the main hull, and transverse bending moments at the junction of the cross structure and main hull. In addition, a parametric optimization of wave loads for different layouts and lengths of side hulls were perfomed. Several speeds and wave headings were also considered. Finally, spectral analysis was conducted to attain load distribution. The conclusions of this study are conducive to the design and optimization of this new type of ship

关键词： trimaran three-dimensional potential theory wave loads optimization

Homotopy　Analysis　Method:A　New　Analytical　Technique　for　Non-linear　Problems

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Communications in Nonlinear Science and Numerical Simulation 1997年第2期2卷 39-44页

作者： Shijun LIAO (Department of Naval Architecture & Ocean engineering, shanghai jiao tong Univ.,shanghai 200030, P. R. china) E-mail: Department of Naval Architecture & Ocean engineering Shanghai Jiao Tong University Shanghai 200030 China

ＨｏｍｏｔｏｐｙＡｎａｌｙｓｉｓＭｅｔｈｏｄ：ＡＮｅｗＡｎａｌｙｔｉｃａｌＴｅｃｈｎｉｑｕｅｆｏｒＮｏｎ－ｌｉｎｅａｒＰｒｏｂｌｅｍｓ１ＳｈｉｊｕｎＬＩＡＯ（ＤｅｐａｒｔｍｅｎｔｏｆＮａｖａｌＡｒｃｈｉｔｅｃｔｕｒｅ... 详细信息

ＨｏｍｏｔｏｐｙＡｎａｌｙｓｉｓＭｅｔｈｏｄ：ＡＮｅｗＡｎａｌｙｔｉｃａｌＴｅｃｈｎｉｑｕｅｆｏｒＮｏｎ－ｌｉｎｅａｒＰｒｏｂｌｅｍｓ１ＳｈｉｊｕｎＬＩＡＯ（ＤｅｐａｒｔｍｅｎｔｏｆＮａｖａｌＡｒｃｈｉｔｅｃｔｕｒｅ＆ＯｃｅａｎＥｎｇｉｎｅｅｒｉｎｇ...

关键词： Nonlinear analytical technique strong nonlinearity homotopy topology

SEM in-situ Fracture Observation and the Reinforcing Effect of Composite SiC_p/ZA22

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Journal of Materials Science & Technology 2001年第6期17卷 649-652页

作者： Jun WANG, Baode SUN and Yaohe ZHOU school of Materials Science and engineering, shanghai jiaotong university, shanghai 200030, china Lining ZHANG and Feng CHEN Department of Materials Science and engineering, Southeast university, shanghai jiao tong Univ Sch Mat Sci & Engn Shanghai 200030 Peoples R China SE Univ Dept Mat Sci & Engn Nanjing 210096 Peoples R China

The strengthening effect of a Zn alloy reinforced by SiC particulate was examined. Based on the results of SEM in-situ fracture observation and stress field analysis by finite element method, it is believed that the r... 详细信息

关键词： SiC SEM in-situ Fracture Observation and the Reinforcing Effect of Composite SiC_p/ZA22

EFFECTS　OF　THERMAL　CYCLE　ON　mechanical　PROPERTIES　OF　SiC　PARTICLES　REINFORCED　MoSi_2　COMPOSITE

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 129-134页

作者： ZHENG Lingyi JIN Yanping LI Pengxing(The State Key Laboratory of Metal Matrix Composites Materials,shanghai jiao tong university,shanghai 200030,china) shanghai jiaotong Univ Shanghai China

MoSi_2 and 30 vol.% SiC_p/MoSi_2 composite have been fabricated by hot pressing (HP).A simulated thermal cycle experiment has been carried out at 1100℃ for 32 h to investigate the stability of the composite ***,mechanical tests,including measurement of flexural strength and fracture toughness at room temperature,have been conducted between materials before and after thermal *** is shown that both the strength and fracture toughness are enhanced by the addition of SiC particles. After thermal cycle,the strength of both materials increases and the toughness decreases by about 20%.The result that the composite system is not corroded intensely by thermal cycle shows that SiC particles are feasible reinforcement for MoSi2.

关键词： thermal cycle MoSi_2 SiC mechanical property interface