均匀外电场中无限长介质圆柱壳的场分布的计算和讨论

用圆柱坐标系中的分离变量法计算了位于均匀外电场中的无限长介质圆柱壳各区域的电势和电场,由计算结果分析了无限长介质圆柱壳对外电场的屏蔽效果,并指出均匀外电场中的无限长导体圆柱壳、无限长介质圆柱体、无限长导体圆柱及无限大均匀电介质中开有一无限长的圆柱形空腔的电势和电场都可以由均匀电场中的无限长介质圆柱壳电势及电场给出.     

均匀磁场中匀速运动的长直圆柱壳场分布的研究

在柱坐标系中用分离变量法计算了位于均匀磁场中匀速运动的长直圆柱壳内外的电场和磁场的分布情况,讨论了运动的长直圆柱壳对外场的屏蔽作用的影响因素.     

均匀外场和介质球系统的电像法求解

为求解均匀外场和介质球系统的势,可将该系统转化为点电荷和介质球系统,再用电像法求解。     

均匀磁场中超导球的准静态磁化

在普通物理知识范围内,根据超导体的迈纳斯效应和磁场边值条件的唯一性,计算出了均匀外磁场中超导球表面的超导电流和磁场分布.     

均匀带电球壳球面电场强度计算方法的讨论

综述近20年来大学物理教学中,关于均匀带电球壳表面电场强度的讨论,概括出3种常见的解法,探讨了不同解法所得不同结果的本质,确定均匀带电球壳表面电场强度的最佳算法.     

介质球在点电荷电场中产生的电势分布规律

推证了介质球在点电荷电场中产生的电势分布规律;同时由此推出了当介质球的电容率ε→∞时,介质球在点电荷的电场中为等电势体,以及金属导体球在点电荷电场中产生的电势分布规律．     

各向异性电介质中均匀带电矩形线框的空间电势和电场强度

从各向异性电介质中点电荷的电势表达式出发,采取分段计算叠加的方法,首先计算了各向异性电介质中均匀带电矩形线框的空间电势.然后,利用电场强度与电势梯度的关系,导出了各向异性电介质中均匀带电矩形线框电场强度的空间分布表达式.最后,对方形均匀带电线框和中心轴线上的特殊情形进行了简单说明.     

外场中介质球周围电势分布的一种新解法

利用点电荷与介质球系统的镜像电荷分布规律以及对外加电场源的等效,并结合场的叠加原理和连带勒让德函数的性质导出在外加电场中介质球周围电势分布的表达式。在此基础上,讨论了几种特殊情形,从而验证了其正确性。本文方法新颖,对于更好地理解球形介质边界的镜像、场的等效原理以及特殊函数在静电势的求解中的应用具有指导意义。     

电偶极子位于均匀介质球中时球外电场的研究

采用分离变量法求解了电偶极子位于均匀介质球中时复连通域的拉普拉斯方程和泊松方程,求出了球内外两种不同介质的电势分布和球面上的极化电荷分布;通过求解二阶非线性微分方程得到了球外的电场线函数;利用计算软件Math-ematica 5.0,作出了相应的相互正交的等势线簇图形和电场线簇图形,并且进行了必要的讨论.     

关于均匀带电球壳表面场强的研究

众所周知,均匀带电球壳在其内部产生的电场强度为零,在其外表面附近产生的电场强度为kQ/R2.那么球壳上产生的电场强度是多少呢?教学过程中很多学生提出了这个问题,不少学生甚至有的教师都认为球壳上的电场强度和球壳外表面附近是     

在均匀磁场中旋转的导体厚球壳上电荷的分布--证明在磁场中转动的导体表面电荷分布无普遍公式

用简单方法求出了在均匀磁场中旋转的导体厚球壳上电荷的分布,证明了在磁场中转动的导体表面电荷分布无普遍公式。     

Electric field distribution around the chain of composite nanoDarticles in ferrofluids

Composite nanoparticles （NPs） have the ability of combining materials with different properties together, thus receiving extensive attention in many fields. Here we theoretically investigate the electric field distribution around core/shell NPs （a type of composite NPs） in ferrofluids under the influence of an external magnetic field. The NPs are made of cobalt （ferromagnetic） coated with gold （metallic）. Under the influence of the external magnetic field, these NPs will align along the direction of this field, thus forming a chain of NPs. According to Laplace＇s equations, we obtain electric fields inside and outside the NPs as a function of the incident wavelength by taking into account the mutual interaction between the polarized NPs. Our calculation results show that the electric field distribution is closely related to the resonant incident wavelength, the metallic shell thickness, and the inter-particle distance. These analytical calculations agree well with our numerical simulation results. This kind of field-induced anisotropic soft-matter systems offers the possibility of obtaining an enhanced Raman scattering substrate due to enhanced electric fields.     

Dirac equation with vector and scalar cornell potentials and an external magnetic field

The two‐dimensional Dirac equation in the presence of vector and scalar Cornell potentials as well as an external magnetic field by a quasiexact methodology are investigated. The closed form of the eigenfunctions is reported and the energy behavior for different states is numerically discussed.     

Electric field distribution around the chain of composite nanoparticles in ferrofluids

Composite nanoparticles (NPs) have the ability of combining materials with different properties together, thus receiving extensive attention in many fields. Here we theoretically investigate the electric field distribution around core/shell NPs (a type of composite NPs) in ferrofluids under the influence of an external magnetic field. The NPs are made of cobalt (ferromagnetic) coated with gold (metallic). Under the influence of the external magnetic field, these NPs will align along the direction of this field, thus forming a chain of NPs. According to Laplace's equations, we obtain electric fields inside and outside the NPs as a function of the incident wavelength by taking into account the mutual interaction between the polarized NPs. Our calculation results show that the electric field distribution is closely related to the resonant incident wavelength, the metallic shell thickness, and the inter-particle distance. These analytical calculations agree well with our numerical simulation results. This kind of field-induced anisotropic soft-matter systems offers the possibility of obtaining an enhanced Raman scattering substrate due to enhanced electric fields.     

均匀带电非理想介质球对外围另一个非理想介质球壳的放电

通过一个非理相介质球对外围另一个介质球放电过程的研究,剖析了各边界面上的面电荷分布,系统耗损的焦耳热与产一磁场等问题。     

Stationary velocity distribution in an external field: A one-dimensional model

The velocity distribution of a charged hard rod coupled to an external field and moving in a neutral equilibrium hard rod gas is studied on the basis of Boltzmann's equation. The exact stationary solution is found. Above a threshold value the field becomes effective in the high-velocity region slowing down the decay of the velocity distribution. The drift velocity and the mean kinetic energy are discussed as functions of the field.     

三氯甲烷在外电场中的物理性质研究

三氯甲烷是挥发性卤代烃,可通过皮肤接触、呼吸或饮水进入人体,危害人体健康,其物理性质的进一步研究对于保护环境与人体健康十分重要.本文采用DFT(密度泛函理论)计算方法,在B3PW91/6-311G+(2d, p)基组水平下对三氯甲烷分子进行优化,从分子结构角度研究了不同外电场作用下,三氯甲烷分子的总能量,键长,电偶极矩,解离势能面,隧穿电离和红外光谱.计算结果表明,随着外加电场的增大,分子键长逐渐增长,偶极矩也随之增加,然而分子的总能量却逐渐减小.分子的最低空轨道能量与最高占据轨道能量之间的能隙也随着外加电场的增大而降低.分子的解离能在增加的电场条件下逐渐降低,吸收光谱的IR强度也有明显的变化.上述的计算结果为利用电场降解三氯甲烷提供重要的理论参考.     

强磁场环境下铁素体钢矩形流体通道内磁场分布研究

用Ansys静磁模块数值模拟了在外加强磁场环境下铁素体矩形通道管中心磁感应强度分布.与文献结果、解析解及实验数据的对比表明,模拟结果与它们基本一致.进一步的数值模拟还表明,铁素体矩形管对其内部的整体磁场分布影响较大,不同区域内产生不同程度的磁力线扭曲及非均匀的磁感应强度分布效应.该分布可能对管道内磁流体动力学效应产生较...     

在时谐电磁场中用矢量势A直接表达电场强度E的一个显式

根据麦克斯韦方程组和洛伦兹条件,对时谐变场e导出用矢量势A直接表达电场强度E的一个显式,并对它进行了讨论.