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Higher order bulk characteristic parameters of asymmetric nuclear matter

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 124-129页

作者： chen liewen1,2.1department of Physics,{2., shanghai 2.02.0, china 2.enter of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, china 1. department of Physics Shanghai Jiao Tong University Shanghai 200240 China 2. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China

The bulk parameters characterizing the energy of symmetric nuclear matter and the symmetry energy defined at normal nuclear density ρ0 provide important information on the equation of state (EOS) of isospin asymmetric nuclear matter. While significant progress has been made in determining some lower order bulk characteristic parameters, such as the energy E0(ρ0) and incompress ibility K0 of symmetric nuclear matter as well as the symmetry energy Esym(ρ0) and its slope parameter L, yet the higher order bulk characteristic parameters are still poorly known. Here, we analyze the correlations between the lower and higher order bulk char acteristic parameters within the framework of Skyrme Hartree-Fock energy density functional and then estimate the values of some higher order bulk characteristic parameters. In particular, we obtain J0 = (-355±95) MeV and I0 = (1473±680) MeV for the third order and fourth-order derivative parameters of symmetric nuclear matter at ρ0 and Ksym = (-100 ± 165) MeV, Jsym = (2.4 ± 385) MeV, Isym = (-1309 ± 2.2.) MeV for the curvature parameter, third-order and fourth-order derivative parameters of the symmetry energy at ρ0, using the empirical constraints on E0(ρ0), K0, Esym(ρ0), L, and the isoscalar and isovector nucleon effective masses. Furthermore, our results indicate that the three parameters E0(ρ0), K0, and J0 can reasonably characterize the EOS of symmetric nuclear matter up to 2.0 while the symmetry energy up to 2.0 can be well described by Esym(ρ0), L, and Ksym.

关键词： equations of state of nuclear matter forces in hadronic systems and effective interactions symmetry energy nuclear density functional theory and extensions asymmetric matter neutron matter

PROPERTIES OF NATURAL CAVITATION FLOWS AROUND A 2.D WEDGE IN SHALLOW WATER

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Journal of Hydrodynamics 2011年第6期23卷 730-736页

作者： chen Xin LU Chuan-jing LI Jie chen Ying department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China department of Engineering Mechanics and State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

When a body navigates with cavity in shallow water, both flexible free surface and rigid bottom wall will produce great influences on the cavity shape and hydrodynamic performances, and further affect the motion attitude and stability of the body. In the present work, characteristics of the natural cavitating flow around a 2.D symmetrical wedge in shallow water were investigated and the influences of two type boundaries on the flow pattern were analyzed. The Volume Of Fluid （VOF） multiphase flow method which is suitable for free surface problems was utilized, coupled with a natural cavitation model to deal with the mass-transfer process between liquid and vapor phases. Within the range of the cavitation number for computation （0.07-1.81）, the cavity configurations would be divided into three types, viz., stable type, transition type and wake-vortex type. In this article, the shapes of the free surface and the cavity surface, and the hydrodynamic performance of the wedge were discussed under the conditions of relatively small cavitation number （〈0.2.6）. The present numerical cavity lengths generally accord with experimental data. When the cavitation number was decreased, the cavity was found to become longer and thicker, and the scope of the deformation of the free surface also gradually extends. The free surface and the upper cavity surface correspond fairly to their shapes. However, the lower side of the cavity surface was rather leveled due to the influence of wall boundary. The lift and drag coefficients of this 2.D wedge basically keep linear relations with the natural cavitation number smaller than 0.157, whereas direct proportion for drag and inverse proportion for lift.

关键词： shallow water natural cavitation boundary effect multiphase flow

Traveling－Wave　Electrooptical　Modulator　on　Polymeric　Film　with　Reversal　Poling　Structure

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Chinese Journal of Lasers 1994年第1期B3卷 57-61页

作者： ZHOU Yi chen Yixin(department of Applied Physics,{2., shanghai2.0030, china)SUN Shiping(department of Electronical Engineering ,shanghai jiao tong university , shanghai 2.0052. china) shanghai jiao{2. Univ Shanghai China

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关键词： reversal poling Electrooptical effect modulator

Study of poly-disperse aerosols deposition in turbulent flow with different Reynolds numbers

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Particuology 2024年第6期89卷 32-43页

作者： Zhichao Gao Yongzheng chen Dandi Zhang Peng chen Lili {2. Xuewu Cao School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China china Nuclear Power Technology Research Institute Co. Ltd.Shenzhen518000China

The turbulent deposition mechanism is one of the main mechanisms of aerosol deposition in nuclear power plant *** experimental study of poly-disperse aerosol deposition in a horizontal tube is conducted,where the nominal Reynolds number(Re)is in a range of 3600–2.0,*** aerosol deposition velocity first increases and then decreases with the increase of Res,and at high Re,particle rebound occurs during aerosol deposition in the *** the Re is low,the aerosol deposition velocity increases with the increase of aerosol *** the Re is greater than 60,000,the deposition velocity first increases and then decreases with the increase of aerosol diameter due to particle surface rebound.A new aerosol deposition model has been developed by establishing the energy conservation equation of the rebounded particles in the viscous *** calculated results of the new model are in good agreement with these experimental results,and the error between the aerosol deposition velocity calculated by the model and experimental results is between−60%and 150%.

关键词： Aerosol Turbulent deposition Rebound High Reynolds number

Computer Simulation of the Structure and Propertiesof Nanocrystals

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Journal of Materials Science & Technology 1994年第6期10卷 418-424页

作者： Da chen(Dept. of Materials Science, shanghai jiao tong university, {2., 2.0030, china) shanghai jiao {2. Univ Shanghai China

This paper provides a computer modeling method for the study of nanocrystals. Structural features,such as the boundary component proportion, the reduced density proportion, the excess lattice parameter, and the radial distribution function, have been atomistically simulated. The energy and elastic properties also have been investigated. Simulation results indicate that the structure of grain boundaries in nanocrystals is different from those of the amorphous and the gas, or rather, it is a special structure with some degree of short-range order. Moreover, the structure of crystallites is not entirely the same as that in the perfect crystal lattice. The present simulation method may become one of the foundations of the theoretical study of nanocrystals.

关键词： Simulation Computer Simulation of the Structure and Propertiesof Nanocrystals BDV

Induced electromagnetic stirring behavior in a resistance spot weld nugget

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Science china(Technological Sciences) 2010年第5期53卷 1271-1277页

作者： LI YongBing1,LIN ZhongQin1,2.LAI XinMin1,2.chen GuanLong1,2.& ZHANG Ke3 1 shanghai Key Laboratory of Digital Autobody Engineering,shanghai jiao tong university,shanghai 2.02.0,china 2.State Key Laboratory of Mechanical System and Vibration,shanghai jiao tong university,shanghai 2.02.0,china 3 Welding Engineering Institute,shanghai jiao tong university,shanghai 2.02.0,china 1. shanghai Key Laboratory of Digital Autobody Engineering Shanghai Jiao Tong University Shanghai 200240 China2. State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China3. Welding Engineering Institute Shanghai Jiao Tong University Shanghai 200240 China

A multi-physics hybrid numerical model,which couples electric,magnetic,thermal and flow fields,was used to investigate electromagnetic stirring behavior in a resistance spot weld *** differences of two kinds of different excitation inputs,i.e.,a sinusoidal current and its root-mean-square(RMS) value,were studied to examine if they could produce equivalent electromagnetic stirring effects in the weld *** showed that the two types of current inputs could produce almost identical fluid flow and heat transfer patterns and consistent evolution of flow and thermal fields in the *** the end of the welding cycles,the maximum flow velocity and temperature between the two inputs differed by 11.6% and 0.3%,***,the RMS current can be assumed to produce an approximately equivalent electromagnetic stirring effect with the sinusoidal current,and can be used in the future research to greatly improve the solution efficiency of the electromagnetic stirring behavior in the resistance spot weld nugget.

关键词： induced magnetic field electromagnetic stirring resistance spot welding fluid flow heat transfer

Beyond 600G fiber-THz wireless seamless integration system employing cascaded MIMO equalizers

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Science china(Technological Sciences) 2024年第7期67卷 2274-2276页

作者： DING JunJie tong WeiDong LI Xintong ZHANG Zheng ZHANG {2. CAI Yuancheng LEI MingZheng HUA BingChang chen XingYu YU JianJun ZHU Min Purple Mountain Laboratories Nanjing 211111China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Fudan university Shanghai 200433China

Terahertz(THz)-wave communication, with sufficient spectrum resources(0.3 THz~10 THz), can meet the needs of future 6G large-capacity mobile communication services[1-9]. Recently, the seamless integration of existing ... 详细信息

关键词： communication fiber wireless

INTERFERENCE OF SIDE STRUT WITH THE NATURAL CAVITATING FLOWS AROUND A SUBMERGED VEHICLE IN WATER TUNNEL EXPERIMENTS

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Journal of Hydrodynamics 2011年第5期23卷 554-561页

作者： chen Xin YAO Yan. LU Chuan-jing chen Ying CAOJia-yi department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China department of Engineering Mechanics and State Key Laboratory of Ocean Engineering Shanghai Jiao TongUniversity Shanghai 200240 China department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China

To apply the measurements of model experiment in water tunnel to the actual sailing condition, it is necessary to know accurately the strut effect and its rule. In the present work, the corresponding interferences of one-side strut and two-side strut on the natural cavitating flows around a submerged vehicle in water tunnel were investigated numerically, using the homogeneous equilibrium two-phase model coupled with a natural cavitation model. The numerical simulation results show that the strut types have distinct effects on the hydrodynamic properties. For the same given upstream velocity and downstream pressure, the existence of the strut leads to an increment of natural cavitation number, reduces the low-pressure region and depresses the pressure on the vehicle surface near the sides of strut. In the case of given cavitaiton number, the influences of the two-side strut on the drag and lift coefficients are both enhanced along with the increment of attack angle, however the influence of the one-side strut gradually gets stronger on the drag coefficient but weaker on the lift coefficient contrarily. In addition, based on the present numerical results, a correction method by introducing the sigmoidal logistic function is proposed to eliminate the interference from the foil-shaped strut.

关键词： strut effect natural cavitating flow submerged vehicle water tunnel experiment

Performance Investigation of Square Concrete-filled Steel Tube Columns

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Journal of Wuhan university of Technology(Materials Science) 2011年第4期26卷 730-736页

作者：陈兵 department of Civil Engineering Shanghai Jiao Tong University

The behaviour of square concrete-filled steel tube columns under concentrical loading was studied. More than one hundred specimens were tested to investigate the effects of thickness of steel tube on the load carrying capacity of the concrete-filled tubular columns （CFTs）. The effect of the grade of concrete and content of expansive agent were also investigated. The effect of these parameters on the confinement of the concrete core was studied as well. From the experimental study it was found that for both CFTs with different strength grade concrete core, the ultimate load carrying capacity increases with the increase in percentage of expansive agent up to 2.% but it again decreases at 2.% of expansive agent content. It was also shown that the failure mode of CFTs depends on the strength grade of concrete core.

关键词： concrete filled steel tubes concrete columns ultimate capacity expansive agent