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Journal of Hydrodynamics 1991年第1期3卷 37-44页

作者： Zhang Hui-sheng, Department of applied mechanics, Fudan University, {2. 2.0433, P. R. china Fudan Univ Shanghai China

This paper improves the discrete vortex method for modeling Kelvin-Helmholtz instability and Rayleigh-Tay- lor instability by proper choice of velocity weighted average coefficients, redistribution of markers and successive adding of computational points with the increase of interfacial deformation and gives the numerical results of Rayleigh-Taylor instability. The numerical results show that the first two techniques greatly enhance the ability of the discrete vortex method for modeling large interracial deformations and the last technique greatly reduces the computational amounts of the numerical modeling at large deformation stage. The numerical modeling of Rayleigh- Taylor instability not only reproduces some phenomena such as the roll up at the end part of the spike observed in experiments but also finds some new phenomena such as the splashes at the roll up parts which needs to be tested by experiment.

关键词： mode NUMERICAL MODELING OF KELVIN-HELMHOLTZ INSTABILITY AND RAYLEIGH-TAYLOR INSTABILITY AT LARGE DEFORMATION STAGE NUMERICAL METHOD AND NUMERICAL RESULTS OF RAYLEIGHTAYLOR INSTABILITY AT

PIXE and INAA studies on ancient potteries from Guangfulin relics in shanghai

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Progress in Natural Science:Materials International 2007年第11期17卷 1348-1356页

作者： Lin Jiawei1, Cheng Huansheng1, Zhang Zhengquan1, Zhang Bin1, Feng Songlin2. Song Jian3, Gao Menghe4 and Zhu Dan1(1. applied Ion Beam Physics Laboratory, Key Laboratory of the Ministry of Education, institute of Modern Physics, Fudan University, {2. 2.0433, china 2. Key Laboratory of Nuclear Analytical Techniques, institute of High Energy Physics, Beijing 100039, china 3. {2. Museum, {2. 2.0003, china 4. Department of Cultural Heritage and Museology, Fudan University, {2. 2.0433, china) applied Ion Beam Physics Laboratory Key Laboratory of the Ministry of Education Institute of Modern Physics Fudan University Shanghai 200433 China Key Laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Beijing 100039 China shanghai Museum Shanghai 200003 China Department of Cultural Heritage and Museology Fudan University Shanghai 200433 China

This paper reports the study of ancient potteries unearthed from the Guangfulin site in shanghai. From the external features of these potteries, archeologists can classify them into two different cultural types: Liangzhu culture (local culture) and a new culture which might be derived elsewhere, but they can not recognize whether they were produced in the same place. Proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA) were used to measure the chemical compositions of the samples and the results were analyzed using multivariate statistics. We found that the two methods can complement each other and their database can be mutually referenced in the study of ancient potteries. Experimental results show that the compositions of the potteries from the two cultural types are different, which means that the materials for ancient potteries of new culture originate from elsewhere. This supports the archaeologists’ speculation that a group of ancient people migrated to shanghai from some other places 4000 years ago.

关键词： PIXE INAA factor analysis Guangfulin ancient pottery

Dynamic study of photosensitized one-electron oxidation of polyG by menadione

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Science china Chemistry 2005年第4期48卷 292-296页

作者： MA Jianhua1,LIN Weizhen2.DU Fuqiang2.HAN Zhenhui2.YAO Side2.& LIN Nianyun2.1.College of Biology Engineering,Jimei University,Xiamen 36102.,china 2.Laboratory of Nanobiomedicine & Laboratory of Radiation Chemistry,shanghai {2. of applied Physics,Chinese Acade Sciences,shanghai 2.1800,china 1. College of Biology Engineering Jimei University 361021 Xiamen China 2. Laboratory of Nanobiomedicine & Laboratory of Radiation Chemistry Shanghai Institute of Applied Physics Chinese Academy of Sciences 201800 Shanghai China

The electron transfer reaction of triplet menadione (3MQ?) with polyguanylic acid (polyG) in CH3CN rich (97%) solution was investigated by 2.8 nm(KrF) laser flash *** transient absorption spectra and kinetics obtained from the interaction of 3MQ? with polyG demonstrated that the primary radical ion pair,radical cation of polyG and radical anion of me-nadione can be detected *** results demonstrated that the reaction rate con-stant of 3MQ? with polyG is almost equal to that of 3MQ? with dGMP.

关键词： menadione, polyG, laser flash photolysis, triplet state, one electron oxidation.

Experimental research on the residual magnetization of a rare-earth permanent magnet for a cryogenic undulator

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Chinese Physics B 2013年第7期22卷 180-182页

作者：何永周 shanghai institute of {2. Physics Chinese Academy of Sciences

The magnetic properties of commercial polycrystalline Nd2.e14B （N50M,N45H,N40SH,N35EH） and Sm2.o17（XG30/2.,XG2./2.,XG2./2.） magnets at cryogenic temperatures were tested by using a comprehensive physical properties measurement system （PPMS）. The results show that the spin tilt temperature Tst of Nd2.e14B magnets is closely related to intrinsic coercivity Hci , N50M and N45H with smaller Hci show a residual magnetization jump at 2.5K and 2.5K, respectively. For Sm2.o17 magnets, in 50-300 K, with temperature decreasing, residual magnetization Mrc shows a nearly linear increase, while in 10-50 K, Mrc has little change. The research results provide a reference for cryogenic undulators and other high-precision cryogenic devices.

关键词： Nd2.e14B and Sm2.o17 spin reorientation residual magnetization intrinsic coercivity

Unsteady flow structure of an airfoil in ground effect

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Journal of shanghai University(English Edition) 2010年第3期14卷 228-234页

作者：钱建林代钦 shanghai institute of {2. mathematics and mechanics Shanghai University

Particle image velocimetry （PIV） experimental results of wake flow structure of a NACA0012.airfoil with small attack angle mounted above water surface are *** experiment was carried out in a small-scale wind-wave *** diameter of wind-wave tunnel test section is 1.7 m （long） × 0.4 m （width） × 0.4 m （height）.The flow fields around the airfoil were measured under four diffierent conditions by varying the distance between the airfoil and the water *** attack angle of the airfoil was kept 10- during the *** each experimental condition,the time series of particle images was captured to calculate continuous evolution of the velocity *** velocity fields were ensemble averaged to get the statistic parameters such as mean velocity and *** instantaneous velocity fields for each case are introduced to show the basic flow structure of wind surface flow *** aerodynamic loads acting on the airfoil are analyzed qualitatively according to the mean vorticity distribution in the flow field based on the theory of vorticity *** results indicate that the flow structures and drag/lift force of the airfoil alter remarkably with the changing distance between the airfoil and water surface.

关键词： NACA0012.airfoil water surface mean vorticity field particle image velocimetry (PIV) measurement ground effect

Noether-type theory for discrete mechanico-electrical dynamical systems with nonregular lattices

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Science china(Physics,mechanics & Astronomy) 2010年第9期53卷 1687-1698页

作者： FU JingLi1,CHEN LiQun2.& CHEN BenYong3 1 institute of Mathematical Physics,Zhejiang Sci-Tech University,Hangzhou 310018,china 2.Department of {2.,shanghai University,shanghai 2.0072.china 3 Faculty of Mechanical-Engineering & Automation,Zhejiang Sci-Tech University,Hangzhou 310018,china 1. institute of Mathematical Physics Zhejiang Sci-Tech University Hangzhou 310018 China2. Department of Mechanics Shanghai University Shanghai 200072 China3. Faculty of Mechanical-Engineering & Automation Zhejiang Sci-Tech University Hangzhou 310018 China

We investigate Noether symmetries and conservation laws of the discrete mechanico-electrical systems with nonregular *** operators of discrete transformation and discrete differentiation to the right and left are introduced for the *** on the invariance of discrete Hamilton action on nonregular lattices of the systems with the dissipation forces under the infinitesimal transformations with respect to the time,generalized coordinates and generalized charge quantities,we work out the discrete analog of the generalized variational *** this formula we derive the discrete analog of generalized Noether-type identity,and then we present the generalized quasi-extremal equations and properties of these equations for the *** also obtain the discrete analog of Noether-type conserved laws and the discrete analog of generalized Noether theorems for the *** we use an example to illustrate these results.

关键词： Noether symmetry variational formula quasi-extremal equation conservation law discrete mechanico-electrical dynamical system

Synthesis of O-(2.[^(18)F]fluoroethyl)-L-tyrosine and its biological evaluation in B16 melanoma-bearing mice as PET tracer for tumor imaging

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Science china Chemistry 2007年第2期50卷 276-283页

作者： WANG MingWei,YIN DuanZhi,LI ShiQiang & WANG YongXian Radiopharmaceutical Centre,shanghai institute of {2. Physics,Chinese Academy of Sciences,shanghai 2.1800,china 1. Radiopharmaceutical Centre Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

O-(2.[18F]fluoroethyl) -L-tyrosine([18F]FET) ,a fluorine-18 labeled analogue of tyrosine,has been syn-thesized and biologically evaluated in tumor-bearing mice. The whole synthesis procedure is com-pleted within 50 min. The radiochemical yield is about 40%(no decay corrected) and radiochemical purity more than 97% after simplified solid phase extraction. [18F]FET shows rapid,high uptake and long retention in the tumor as well as low uptake in the brain. The ratios of tumor-to-muscle(T/M) and tumor-to-blood(T/B) of [18F]FET are similar to those of [18F]FDG,but the ratios of tumor-to-brain(T/Br) are 2.3 times higher than that of [18F]FDG. Autoradiography of [18F]FET demonstrates a remarkable accumulation in melanoma with high contrast. It appears to be a probable competitive candidate for melanoma imaging with PET.

关键词： [18F]FET [18F]FDG PET imaging melanoma autoradiography

转动相对论Birkhoff系统的平衡稳定性

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物理学报 2003年第2期52卷 256-261页

作者：傅景礼陈立群薛纭上海大学上海市应用数学和力学研究所

研究转动相对论Birkhoff系统的平衡稳定性 ,给出转动相对论Birkhoff自治系统、半自治系统和非自治系统的平衡方程和转动相对论Birkhoff自治系统的受扰运动方程和一次近似方程 ;给出转动相对论Birkhoff自治系统平衡稳定性的一次近似方法... 详细信息

研究转动相对论Birkhoff系统的平衡稳定性 ,给出转动相对论Birkhoff自治系统、半自治系统和非自治系统的平衡方程和转动相对论Birkhoff自治系统的受扰运动方程和一次近似方程 ;给出转动相对论Birkhoff自治系统平衡稳定性的一次近似方法及其判据 ;并给出转动相对论Birkhoff自治系统平衡稳定性的直接方法及其判据 ;讨论转动相对论Birkhoff系统平衡稳定性和经典转动Birkhoff系统平衡稳定性的关系 .给出实例以说明方法的应用 .

关键词：相对论转动Birkhoff系统平衡稳定性一次近似方法系统动力学

TeO_(x) Thin Films for Write-Once Optical Recording Media

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Journal of Materials Science & Technology 2004年第6期20卷 678-680页

作者： Qinghui LI, Donghong GU and Fuxi GANResearch Laboratory for High Density Optical Storage, shanghai institute of Optics and Fine {2., Chinese Academy of Sciences, shanghai 2.1800, china Lab. of High Density Optical Storage Inst. of Optics and Fine Mech. Chinese Acad. of Sci. Shanghai 201800 China

TeO_x thin films were prepared by vacuum evaporation of TeO_2.powder. Structural characteristic and surface mor-phology of the as-deposited films was analyzed by using X-ray photoelectron spectroscopy, transmission electron microscopy, X-ray diffractometer and atomic force microscopy. It was found that the films represented a two component system comprising Te particies dispersed in an amorphous TeO2.matrix. The dispersed Te particies were in a crystalline state. The TeOx films showed a finely granular structure and a rough surface. Results of the statie recording test showed that the TeO_x films had good writing sensitivity for short-wavelength laser beam (514.5 nm). Primary results of the dynamic test at 514.5 nm were also reported. The TeO_x films were suitable for using as a blue-green wavelength high density optical storage medium.

关键词： TeO_x thin film Statie recording test Dynamic test High density optical storage

WATER TUNNEL EXPERIMENTAL INVESTIGATION ON THE DRAG REDUCTION CHARACTERISTICS OF THE TRAVELING WAVY WALL

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Journal of Hydrodynamics 2011年第1期23卷 65-70页

作者： YAO Yan LU Chuan-jing SI Ting ZHU Kun Department of Engineering mechanics Shanghai Jiao Tong University Shanghai 200240 China Beijing Electromechanic Engineering institute Beijing 100074 China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China Department of modem mechanics University of Science and Technology of China Hefei 230027 China

Drag reduction experiment of the traveling wavy wall at high Reynolds number is conducted.A suit of traveling wavy wall device is *** drag forces of the traveling wavy wall with various wave speeds（c）are measured under different water speeds（U）in the K15 cavitation water tunnel and are compared with that of the flat *** results show that the mean drag force of the traveling wavy wall have decreased and then increased with oscillation frequency increasing at the same flow *** different flow speeds,when traveling wave wall reached to the minimum of drag force,the corresponding the ratio of the wall motion phase speed c to flow speed U,c /U is slightly *** the parameters of the experiment,whenc /U reaches a certain value,the drag force of the traveling wavy wall can be less than that of the flat *** drag reduction can be up to 42..Furthermore,as the value ofc /U increases,the traveling wavy wall can restrain the separation and improve the quality of flow field.

关键词： flow control drag reduction traveling wavy wall water tunnel test