以小论文进行有机化学考试的尝试

本科三年级有机化学以写小论文进行考试 ,提供了操作的雏形。试验表明 ,有利于培养学生的综合能力及科学素质 ,作法可行     

旋波媒质中谱域电并矢Green函数的分解

介绍了一种推导无耗、互易和无界旋波媒质中谱域并矢Green函数表达式的新方法·　这种方法以Hemholtz定理以及并矢Diracδ函数的无散和无旋分解为基础,首先将电矢量的并矢Green函数方程分解成无散电矢量的并矢Green函数方程和无旋电矢量的并矢Green函数方程,然后经Fourier变换导出了旋波媒质中谱域电并矢Green函数的无散分解表达式和无旋分解表达式·　用这种方法推导旋波媒质中并矢Green函数就可以避免必须用波场的分解法和并矢Green函数的本征函数展开法·     

SPLITTING OF THE SPECTRAL DOMAIN ELECTRICAL DYADIC GREEN’S FUNCTION IN CHIRAL MEDIA

IntroductionAchiralmediumisanewtypeofspecialmediummaterial.Broadapplicationprospectsforchiralmediainmicrowaves,millimeterwaves,electronicdevices,integratedoptics,andsoonfieldhaveattractedconsiderableattention .Theelectromagneticproblemwithchiralmediahasbeenahotresearchtopicoftheelectromagnetictheory .TheeigenfunctionexpansionproblemofthedyadicGreen’sfunctionfortheelectromagneticwavefieldinchiralmediahasbeendeeplyinvestigatedinRefs [1～ 6] .FromHelmholtztheorem ,anarbitraryvectorfieldfcouldb…     

SPLITTING OF THE SPECTRAL DOMAIN ELECTRICAL DYADIC GREEN’S FUNCTION IN CHIRAL MEDIA

A new method of formulating dyadic Green‘s functions in lossless , reciprocal and unbounded chiral medium was presented. Based on Helmholtz theorem and the nondivergence and irrotational splitting of dyadic Dirac delta-function was this method, the electrical vector dyadic Green‘s function equation was first decomposed into the nondivergence electrical vector dyadic Green‘s function equation and irrotational electrical vector dyadic Green‘s function equation, and then Fourier‘s transformation was used to derive the expressions of the non-divergence and irrotational component of the spectral domain electrical dyadic Green‘s function in chiral media. It can avoid having to use the wavefield decomposition method and dyadic Green‘s function eigenfunction expansion technique that this method is used to derive the dyadic Green‘s functions in chiral media.