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A study of constraints on the constitutive relationships of electromagnetic medium based on generally acknowledged truths

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Science China(Physics,Mechanics & Astronomy) 2005年第5期48卷 541-548页

作者： GUO Huiping1, LIU Xueguan1,2, YIN Hongcheng2, CHAO Zengming2 & HUANG Peikang2 1. School of Electronics and Information Engineering, Soochow University, Suzhou 215021, China 2. National Electromagnetic Scattering Laboratory, Beijing 100854, China 1. School of Electronics and Information Engineering Soochow University 215021 Suzhou China 2. National Electromagnetic Scattering Laboratory 100854 Beijing China

The study of constraints on the constitutive relationships of electromagnetic media is of great importance in the aspects of the medium characteristics analysis, the new article material synthesis and the medium parameters reconstruction, etc. According to the fact that the constitutive relationships should not conflict with the general physical laws, the constraints that the constitutive relationships of electromagnetic medium must satisfy have been summarized in this paper. These constraints include determinacy principle, objectivity principle, causality principle and permission principle. And the parameter constraints of the arbitrary linear homogenous time-invariant medium are obtained following the minimum energy consumption principle. This work provides a new way of ascertaining the constitutive relationships of the electromagnetic medium.

关键词： electromagnetic medium, medium parameter constraint, generally acknowledged truths, energy conservation principle, minimum energy consumption principle.

New high-velocity bipolar outflows in S39 and IRAS 06306+0232

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Science China Mathematics 2002年第4期45卷 538-544页

作者：秦胜利吴月芳 1. Department of Astronomy Peking University 100871 Beijing China 2. CAS-PKU Joint Beijing Astrophysics Center 100871 Beijing China

Mapping observations in12CO J = 1 - 0 lines were made towards S39 and IRAS 06306 + 0232 with the 13.7 m radio telescope at Qinghai Station of Purple Mountain Observatory. The results showed that both of them have bipolar outflows. We have calculated the outflow parameters. The outflows have significantly more mass and higher mass loss rate than those from low mass YSOs. We also find that although the bolometric luminosities of the associated sources are large, the radiation pressure of wind is not sufficient to drive the observed outflows. There exist several stars of different evolve states in S39. It suggests that the star formation in S39 is in sequence, not in eruption.

关键词： interstellar medium, jets and outflows, star formation.

Rapid transient explosive boiling of binary mixture under pulsed-laser irradiation

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Science China(Technological Sciences) 2003年第5期46卷 490-497页

作者：淮秀兰刘登瀛董兆一金仁喜王国祥 Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100080 China Department of Mechanical Engineering The University of Akron Akron Ohio 44325-3903 USA

Rapid transient explosive boiling of mixed ethanol and acetone of different volume fractions were investigated experimentally. The temperature of the metal film surface irradiated by a pulse laser was measured by a fast-response measurement system with a platinum film resistor. The behaviors of bubbles, including their formation, growth, departure and floating-up, were observed and captured by a microscope camera system. It was found that bubble nucleation temperature depends strongly on the heating rate. Some special characteristics different from those of conventional boiling were revealed, and the factors affecting explosive boiling were studied.

关键词： pulsed laser, mixture medium, explosive boiling, temperature measurement.

Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media(Ⅱ)

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 422-430页

作者： CAI Ruixian1, GOU Chenhua1, 2 & ZHANG Na1 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, China 2. Graduate School, Chinese Academy of Sciences, Beijing 100080, China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Graduate School Chinese Academy of Sciences 10080 Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model―an improved Darcy model―describing the natural convection in porous media. Besides their important theoretical meaning (for example, in analyzing the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions that can promote the development of computational heat and mass transfer. Some solutions considering the anisotropic effect of permeability have been given previously by the authors, and this paper gives solutions including the anisotropic effect of thermal conductivity and the effect of heat sources.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.

Refraction of light in media

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 591-600页

作者： ZHANG Tao Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875, China Beijing Radiation Center, Beijing 100875, China Key Laboratory of Beam Technology Material Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China

The roles of the magnetic field and electric field of the light are investigated when the light is refracted in the medium. The model of the electron cloud conductor is presented. Electron cloud in a molecule is treated as a conductor and the Faraday’s Law is applied to this conductor that is in the alternating magnetic field of the light. dBM/dt of the light gives rise to an alternating induced current on the electron cloud conductor, and the light exchanges energy, i.e. the refractive energy, with the elec- tron cloud conductor. Formulas of refractive index, which is the ratio of light speed in vacuum to that in the medium, are derived with this model. These formulas are tested with several mediums and Langevin’s diamagnetic susceptibility of helium gas, and the results are in good agreement with the measured data. The anisotropy and the nonlinearity of the refractive index are explained with the theory described in this work.

关键词： refractive index, light, speed, medium, propagation

Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media

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Science China Mathematics 2002年第6期45卷 808-816页

作者：蔡睿贤张娜 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model an improved Darcy model describing the natural convection in porous media. Besides their important theoretical meaning (for example, to analyze the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions to promoting the develop ment of computational heat and mass transfer. For instance, we can use them to check the accuracy,convergence and effectiveness of various numerical computational methods and to improve numerical calculation skills such as differential schemes and grid generation ways.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.