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    题名 作者 年代 出处 被引量
1Homotopic mapping solving method for gain fluency of a laser pulse amplifier显示文摘The model for gain fluency of a laser pulse amplifier is studied. Using the homotopic mapping method, firstly, the system of the original model is packed up standardization; secondly, introducing a homotopic mapping, taking the property of the mapping, inducing a contrived parameter, the solving of a nonlinear problem translates into the solving of a linear problem. Then the approximate expressions of the solution for the corresponding model are obtained. And the precision for the approximate solution is compared. It illuminates that the obtained approximate solution using the homotopic mapping method possesses higher approximate degree. At one time, the expansion of solution through the homotopic mapping method can be kept in the analytic operation. Thus it also enables us through differential and integral operations to obtain other physics behavior for the gain fluency of laser pulse amplifier.MO JiaQi1,2 1 Anhui Normal University, Wuhu 241000, China 2 Division of Computational Science, E-Institutes of Shanghai Universities, at SJTU, Shanghai 200240, China 2009Science China(Physics,Mechanics & Astronomy)2009,52,7:124
2A MODIFIED LEVENBERG-MARQUARDT ALGORITHM FOR SINGULAR SYSTEM OF NONLINEAR EQUATIONS显示文摘Based on the work of paper,we propose a modified Levenberg-Marquardt algoithm for solving singular system of nonlinear equations F(x)=0,where F(x):R^n→R^n is continuously differentiable and F'(x)is Lipschitz continuous.The algorithm is equivalent to a trust region algorithm in some sense,and the global convergence result is given.The sequence generated by the algorithm converges to the solution quadratically,if ||F(x)||2 provides a local error bound for the system of nonlinear equations.Numerical results show that the algorithm performs well.Jin-yan Fan (Department of Mathematics, Shanghai Jiaotong University, Shanghai 200240, China) 2003Journal of Computational Mathematics2003,21,5:27
3Third-order point contact approach for five-axis sculptured surface machining using non-ball-end tools (Ⅰ): Third-order approximation of tool envelope surface显示文摘In this paper, the geometric properties of a pair of line contact surfaces are investigated. Then, based on the observation that the cutter envelope surface contacts with the cutter surface and design surface along the characteristic curve and cutter contact (CC) path, respectively, a mathematical model describing the third-order approximation of the cutter envelope surface according to just one given cutter location (CL) is developed. It is shown that at the CC point both the normal curvature of the normal section of the cutter envelope surface and its derivative with respect to the arc length of the normal section can be determined by those of the cutter surface and design surface. This model characterizes the intrinsic relationship among the cutter surface, cutter envelope surface and design surface in the neighborhood of the CC point, and yields the mathematical foundation for optimally approximating the cutter envelope surface to the design surface by adjusting the cutter location.ZHU LiMin1, DING Han2 & XIONG YouLun2 1 State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240, China 2 State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China 2010Science China(Technological Sciences)2010,53,7:25
4Phosphate removal and recovery through crystallization of hydroxyapatite using xonotlite as seed crystal显示文摘Xonotlite was synthesized and tested for phosphate removal and recovery from synthetic solution in a batch mode. The effects of pH, initial calcium concentration, bicarbonate concentration on phosphate removal through crystallization were examined. The morphology and X-ray diffraction (XRD) pattern of xonotlite before and after crystallization confirmed the formation of crystalline hydroxyapatite. The results indicated that the crystallization product had a very high P content (> 10%), which is comparable to phosphate rock at the dosage of 50-200 mg xonotlite per liter, with a maximum P content of 16.7%. The kinetics of phosphate removal followed the second-order reaction equation. The phosphate removal ability increased with increasing pH. The precipitation of calcium phosphate took place when pH was higher than 7.2, whereas the crystallization occurred at pH 6.0. A high calcium concentration could promote the removal of phosphate via crystallization, while a high bicarbonate concentration also enhanced phosphate removal, through that the pH was increased and thus induced the precipitation process. When xonotlite was used to remove phosphate from wastewater, the removal effciency could reach 91.3% after 24 h reaction, with removal capacity 137 mg/g. The results indicated that xonotlite might be used as an effective crystal seed for the removal and recovery of phosphate from aqueous solution.CHEN Xuechu, KONG Hainan, WU Deyi, WANG Xinze, LIN Yongyong School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China 2009Journal of Environmental Sciences2009,21,5:24
5Lie bialgebras of generalized Witt type显示文摘In this paper, all Lie bialgebra structures on the Lie algebras of generalized Witt type are considered. It is proved that, for any Lie algebra W of generalized Witt type, all Lie bialgebras on W are the coboundary triangular Lie bialgebras. As a by-product, it is also proved that the first cohomology group H1(W, W (x) W) is trivial.SONG Guang’ai & SU Yucai College of Mathematics and Information Science, Shandong Institute of Business and Technology, Yantai 264005, China Department of Mathematics, University of Science and Technology of China, Hefei 230026, China Department of Mathematics, Shanghai Jiaotong University, Shanghai 200240, China 2006Science China Mathematics2006,49,4:22
6Global optimization of tool path for five-axis flank milling with a cylindrical cutter显示文摘In this paper, optimum positioning of cylindrical cutter for five-axis flank milling of non-developable ruled surface is addressed from the perspective of surface approximation. Based on the developed interchangeability principle, global optimization of the five-axis tool path is modeled as approximation of the tool envelope surface to the data points on the design surface following the minimum zone criterion recommended by ANSI and ISO standards for tolerance evaluation. By using the signed point-to-surface distance function, tool path plannings for semi-finish and finish millings are formulated as two constrained optimization problems in a unified framework. Based on the second order Taylor approximation of the distance function, a sequential approximation algorithm along with a hierarchical algorithmic structure is developed for the optimization. Numerical examples are presented to confirm the validity of the proposed approach.DING Han1 & ZHU LiMin2 1 State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China 2 School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China 2009Science China(Technological Sciences)2009,52,8:23
7Third-order point contact approach for five-axis sculptured surface machining using non-ball-end tools(II): Tool positioning strategy显示文摘Based on the mathematical model describing the third-order approximation of the cutter envelope surface according to one given cutter location(CL),a tool positioning strategy is proposed for efficiently machining free-form surfaces with non-ball-end cutters.The optimal CL is obtained by adjusting the inclination and tilt angles of the cutter until its envelope surface and the design surface have the third-order contact at the cutter contact(CC)point,which results in a wide machining strip.The strategy can handle the constraints of machine joint angle limits,global collision avoidance and tool path smoothness in a nature way,and can be applied to general rotary cutters and complex surfaces.Numerical examples demonstrate that the third-order point contact approach can improve the machining strip width greatly as compared with the recently reported second-order one.ZHU LiMin 1 ,DING Han 2 &XIONG YouLun 2 1State Key Laboratory of Mechanical System and Vibration,Shanghai Jiao Tong University,Shanghai 200240,China 2State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and Technology,Wuhan 430074, China 2010Science China(Technological Sciences)2010,53,8:23
8Strong law of large numbers for Markov chains indexed by an infinite tree with uniformly bounded degree显示文摘In this paper,we study the strong law of large numbers and Shannon-McMillan (S-M) theorem for Markov chains indexed by an infinite tree with uniformly bounded degree.The results generalize the analogous results on a homogeneous tree.HUANG HuiLin~1 YANG WeiGuo~(2+) 1 Department of Mathematics,Shanghai Jiaotong University,Shanghai 200240,China 2 Faculty of Science,Jiangsu University,Zhenjiang 212013,China 2008Science China Mathematics2008,51,2:23
9Metal chlorides loaded on activated carbon to capture elemental mercury显示文摘Activated carbon (AC) was considered to be an effective sorbent to control mercury in combustion systems. However, its capture capacity was low and it required a high carbon-to-mercury mass ratio. AC loaded with catalyst showed a high elemental mercury (Hg 0 ) capture capacity due to large surface area of AC and high oxidization ability of catalyst. In this study, several metal chlorides and metal oxides were used to promote the sorption capacity of AC. As a result, metal chlorides were better than metal oxides loaded on AC to remove gaseous mercury. X-ray diffractometer (XRD), thermogravimetric analyzer (TGA) and specific surface area by Brunauer- Emmett-Teller method (BET) analysis showed the main mechanisms: first, AC had an enormous surface area for loading enough MClx; second, Cl and MxOy were generated during pyrogenation of MClx; finally, there were lots of active elements such as Cl and MxOy which could react with elemental mercury and convert it to mercury oxide and mercury chloride. The HgO and HgCl 2 might be released from AC's porous structure by thermo regeneration. A catalytic chemisorption mechanism predominates the sorption process of elemental mercury. As Co and Mn were valence variable metal elements, their catalytic effect on Hg 0 oxidization may accelerate both oxidation and halogenation of Hg 0 . The sorbents loaded with metal chlorides possessed a synergistic function of catalytic effect of valence variable metal and chlorine oxidation.Zhemin Shen,Jing Ma,Zhijian Mei,Jianda Zhang School of Environmental Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China 2010Journal of Environmental Sciences2010,22,11:18
10Biosorption of Cu(Ⅱ) on extracellular polymers from Bacillus sp.F19显示文摘Biosorption can be an effective process for the removal of heavy metals from aqueous solutions.The adsorption of Cu(Ⅱ) from aqueous solution on the extracellular polymers (EPS) from Bacillus sp.(named MBFF19) with respect to pH,incubation time,concentration of initial Cu(Ⅱ),and biosorbent dose was studied.Biosorption of Cu(Ⅱ) is highly pH dependent.The maximum uptake of Cu(Ⅱ) (89.62 mg/g) was obtained at pH 4.8.Biosorption equilibrium was established in approximately 10 min.The correlation coeffcient of more than 0.90 turned out that the adsorption process of Cu(Ⅱ) on MBFF19 was in accordance with both Langmuir and Freundlich isotherms.The pseudo-first and second order models were applied to examine the kinetics of the adsorption,whereas the latter was found to be in harmony with the kinetic data better.Because of the outstanding uptake capacity of Cu(Ⅱ),MBFF19 produced by Bacillus sp.was proved to be an excellent biosorbent for removing Cu(Ⅱ) from aqueous solutions.ZHENG Yan,FANG Xuliang,YE Zhilong,LI Yahong,CAI weimin School of Environmental Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China. 2008Journal of Environmental Sciences2008,20,11:15
11Flow visualization of silicon-based micro pulsating heat pipes显示文摘Two sets of silicon-based micro pulsating heat pipes(SMPHPs) with trapezoidal cross section having hydraulic diameters of 352 μm(#1) and 394 μm(#2) respectively were fabricated for the first time using MEMS technology.With FC-72 as the working fluid,the start-up,steady operation state,as well as flow patterns were investigated using a CCD camera.It was found that the start-up process of these two SMPHPs was rather rapid.At the start-up period,no nucleation was observed,and the vapor plugs at the evaporator U-bends were formed mainly due to the breakup of liquid slugs.At the steady operation state,self-sustained oscillation with large amplitudes dominated the flow behavior when the inclination angle varied from 10° to 90°,but the nucleate boiling and bulk circulation were observed only in SMPHP #2.While bubbly,slug/plug,annular/semi-annular,and wavy-annular flows were observed in both two SMPHPs,the injection flow only appeared in SMPHP #2.QU Jian & WU HuiYing Key Laboratory for Power Machinery and Engineering of Ministry of Education,School of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 200240,China 2010Science China(Technological Sciences)2010,53,4:13
12AN APPROACH IN MODELING TWO-DIMENSIONAL PARTIALLY CAVITATING FLOW显示文摘An approach of modeling viscosity, unsteady partially cavitating flows around lifting bodies is presented. By em ploying an one-fluid Navier-Stokers solver, the algorithm is proved to be able to handle two-dimensional laminar cavitating flows at moderate Reynolds numbe r. Based on the state equation of water-vapor mixture, the constructive relatio ns of densities and pressures are established. To numerically simulate the cavi ty wall, different pseudo transition of density models are presumed. The finite-volume method is adopted and the algorithm can be extended to three-dimensional cavitating flows.Wu Lei, Lu Chuan-jing, Xue Lei-ping (Department of Engineering Mechanics, Shanghai Jiaotong Un iversity, Shanghai 200240, China) 2002Journal of Hydrodynamics2002,14,1:12
13Wholly smoothing cutter orientations for five-axis NC machining based on cutter contact point mesh显示文摘Cutting forces with respect to different cutter orientations are analyzed for five-axis NC machining of a ball-end cutter.A measure is then defined to quantify the effects of cutter orientation variation.According to the measure,a novel model and algorithm are proposed to wholly optimize cutter orientations based on a cutter contact(CC) point mesh.The method has two advantages.One is that the cutter orientation smoothnesses along the feed direction and pick-feed direction are both wholly optimized.The other is that only the accessibility cones of mesh points are required to compute and the computation efficiency is improved.These advantages are shown by simulating the machining efficiency,the stability of feed velocities and the smoothness of cutting force.A computational example and a cutting experiment are finally given to illustrate the validity of the proposed method.BI QingZhen,WANG YuHan,ZHU LiMin & DING Han State Key Laboratory of Mechanical System and Vibration,School of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 200240,China 2010Science China(Technological Sciences)2010,53,5:12
142-Cocycles of original deformative Schrdinger-Virasoro algebras显示文摘Both original and twisted Schrdinger-Virasoro algebras, and also their deformations were introduced and investigated in a series of papers by Henkel, Roger and Unterberger. In the present paper we aim at determining the 2-cocycles of original deformative Schrdinger-Virasoro algebras.LI JunBo1, 2 , SU YuCai3 & ZHU LinSheng21 Department of Mathematics, Shanghai Jiao Tong University, Shanghai, 200240, China 2 Department of Mathematics, Changshu Institute of Technology, Changshu 215500, China 3 Department of Mathematics, University of Science and Technology of China, Hefei 230026, China 2008Science China Mathematics2008,51,11:12
15AtMYB103 is a crucial regulator of several pathways affecting Arabidopsis anther development显示文摘Previous reports indicated that AtMYB103 has an important role in tapetum development,callose dissolution,and exine formation in A.thaliana anthers.Here,we further characterized its function in anther development by expression pattern analysis,transmission electron microscopy observation of the knockout mutant,and microarray analysis of downstream genes.A total of 818 genes differentially expressed between ms188 and the wild-type were identified by global expression profiling analysis.Functional classification showed that loss-of-function of AtMYB103 impairs cell wall modification,lipid metabolic pathways,and signal transduction throughout anther development.RNA in situ hybridization confirmed that transcription factors acting downstream of AtMYB103 (At1g06280 and At1g02040) were expressed in the tapetum and microspores at later stages,suggesting that they might have important roles in microsporogenesis.These results indicated that AtMYB103 is a crucial regulator of Arabidopsis anther development.ZHU Jun1,ZHANG GuoQiang2,CHANG YuHua2,LI XiaoChuan2,YANG Jun2,HUANG XueYong2,YU QingBo2,CHEN Hui3,WU TianLong1* & YANG ZhongNan2* 1College of Agriculture and Biotechnology,Shanghai Jiao Tong University,Shanghai 200240,China 2College of Life and Environmental Sciences,Shanghai Normal University,Shanghai 200234,China 3Shanghai Institute of Plant Physiology and Ecology,Chinese Academy of Sciences,Shanghai 200032,China 2010Science China(Life Sciences)2010,53,9:10
16Advanced technology for functionalization of carbon nanotubes显示文摘Functionalization of carbon nanotubes (CNTs) has attracted considerable interest in the fields of physics, chemistry, material science and biology. The functionalized CNTs exhibit improved properties enabling facile fabrication of novel nanomaterials and nanodevices.Most of the functionalization approaches developed at present could be categorized into the covalent attachment of functional groups and the non-covalent adsorption of various functional molecules onto the surface of CNTs. This review highlights recent development and our work in functionalization of carbon nanotubes, leading to biocompatible CNTs, fluorescent CNTs and transition metal functionalized CNTs. These novel methods possess advantages such as simplified technical procedures and reduced cost of novel nanomaterials and nanodevices fabrication.Lingjie Meng, Chuanlong Fu, Qinghua Lu School of Chemistry and Chemical Technology, Shanghai Jiaotong University, Shanghai 200240, China 2009Progress in Natural Science:Materials International2009,19,7:10
17NUMERICAL SIMULATIONS OF CAVITATING FLOWS显示文摘A new model, which involves viscous and multi-phase effects, was given to study cavitating flows. A local compressible model was established by introducing a density-pressure function to account for the two-phase flow of water/vapor and the transition from one phase to the other. An algorithm for calculating variable-density N-S equations of cavitating flow problem was put forward. The present method yields reasonable results for both steady and unsteady cavitating flows in 2D and 3D cases. The numerical results of unsteady character of cavitating flows around hydrofoils coincide well with experimental data. It indicates the feasibility to apply this method to a variety of cavitating flows of practical problems.Ph.D.Candidate:Wu Lei School of Civil Engineering and Mechanics, Shanghai Jiaotong University, Shanghai 200240, China Supervisor:Lu Chuan-jing (Shanghai Jiaotong University) Xue Lei ping (Shanghai Jiaotong University) Members of Dissertation Defense Committee:Dong Shi-tang (China Ship Scientific Research Center),Chairman Dai Shi-qiang (Shanghai University) Zhang Hui-sheng (Fudan University) Miao Guo-ping (Shanghai Jiaotong Universi ty) He You-sheng (Shanghai Jiaotong University)Liu Hua (Shanghai Jiaotong University) Lu Chuang-jing (Shanghai Jiaotong Universi ty) 2003Journal of Hydrodynamics2003,15,4:9
18Identification of an avirulence gene,avrxa5,from the rice pathogen Xanthomonas oryzae pv.oryzae显示文摘Xanthomonas oryzae pv.oryzae,the causal agent of bacterial blight in rice,interacts with rice plants in a gene-for-gene manner.The specificity of the interaction is dictated by avirulence(avr) genes in the pathogen and resistance(R) genes in the host.To date,no avr genes that correspond to recessive R genes have been isolated.We isolated an avrBs3/pthA family gene,avrxa5,from our previously isolated clone p58,which was originally from strain JXOIII.The avrxa5 gene converted the PXO99A strain from compatible to incompatible in rice cultivars containing the recessive xa5 gene,but not in those containing the dominant Xa5 gene.Sequencing indicated that avrxa5,which is highly similar to members of the avrBs3/pthA family,encodes a protein of 1238 amino acid residues with a conserved carboxy-terminal region containing three nuclear localization signals and a transcription activation domain.It has 19.5 34-amino-acid direct repeats,but the 13th amino acid is missing in the fifth and ninth repetitive units.Domain swapping of the repetitive regions between avrxa5 and avrXa7 changed the avirulence specificity of the genes in xa5 and Xa7 rice lines,respectively.This indicates that avrxa5 is distinct from previously characterized avrBs3/pthA members.The specificity of avrxa5 toward recessive xa5 in rice could help us better understand the molecular mechanisms of plant-pathogen specific interactions.ZOU HuaSong1,ZHAO WenXiang2,ZHANG XiFu3,HAN YangChun2,ZOU LiFang2 & CHEN GongYou1,2* 1School of Agriculture and Biology,Shanghai Jiaotong University,Shanghai 200240,China 2College of Plant Protection,Nanjing Agricultural University/Laboratory for Monitoring and Management for Plant Pests and Diseases,Chinese Ministry of Agriculture,Nanjing 210095,China 3Department of Agronomy,Henan Vocation-Technical Teachers College,Xinxiang 453003,China 2010Science China(Life Sciences)2010,53,12:9
19Approximate homotopy symmetry method:Homotopy series solutions to the sixth-order Boussinesq equation显示文摘An approximate homotopy symmetry method for nonlinear problems is proposed and applied to the sixth-order Boussinesq equation,which arises from fluid dynamics.We summarize the general formulas for similarity reduction solutions and similarity reduction equations of different orders,educing the related homotopy series solutions.Zero-order similarity reduction equations are equivalent to the Painlevé IV type equation or Weierstrass elliptic equation.Higher order similarity solutions can be obtained by solving linear variable coefficients ordinary differential equations.The auxiliary parameter has an effect on the convergence of homotopy series solutions.Series solutions and similarity reduction equations from the approximate symmetry method can be retrieved from the approximate homotopy symmetry method.JIAO XiaoYu1,GAO Yuan1 & LOU SenYue1,2,3 1 Department of Physics,Shanghai Jiao Tong University,Shanghai 200240,China 2 Department of Physics,Ningbo University,Ningbo 315211,China 3 School of Mathematics,Fudan University,Shanghai 200433,China 2009Science China(Physics,Mechanics & Astronomy)2009,52,8:8
20Coupled modeling of tumour angiogenesis, tumour growth,and blood perfusion显示文摘This paper proposes a more realistic mathematical simulation method to investigate the dynamic process of tumour angio-genesis by fully coupling the vessel growth,tumour growth and associated blood perfusion.The tumour growth and angiogenesis are coupled by the chemical microenvironment and the cell-matrix interaction.The haemodynamic calculation is carried out on the new vasculature,and an estimation of vessel collapse is made according to the wall shear stress criterion.The results are consistent with physiological observations,and further confirm the application of the coupled model feedback mechanism.The model is available to examine the interactions between angiogenesis and tumour growth,to study the change in the dynamic process of chemical environment and the vessel remodeling.Y.Cai,1,2 S.X.Xu,1,a) J.Wu,3 and Q.Long 2,b) 1) Department of Mechanics and Engineering Science,Fudan University,Shanghai 200433,China 2) Brunel Institute for Bioengineering,School of Engineering and Design,Brunel University,Uxbridge,Middlesex,UK 3) School of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiaotong University,Shanghai 200240,China 2011Theoretical & Applied Mechanics Letters2011,1,4:8
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