再谈"三维导体"的自感系数

由公式ε＝Ｌ│ｄＩ／ｄｔ│出发，只要求出“三维导体”中的等效自感电动势，即可求得自感系数Ｌ，并以无限长同轴电缆自感系数的求解为例加以证明。     

稳恒和交变电流系的矢势多极展开

以矢量分析和张量分析为基础，给出了小区域内稳恒电流系和交变电流系矢势多极展开的共同方法。     

对柱对称电流分布磁矢势问题的讨论

采用柱对称性和叠加原理讨论了均匀载流圆环、圆筒、圆盘的矢势问题．     

利用磁矢势求解涡旋电场

给出了一种利用磁矢势计算涡旋电场的一般方法,并结合实例验证,以深化学生对磁矢势和涡旋电场概念的理解.     

也谈“三维导体”的自感系数

读了颜家壬同志《求三维导体自感系数的另一方法》一文[1],颇受启发,也想就此问题发表一些议论. 文[1]中所谓“三维导体”是指“有一定横截面积的导体回路”,本人更倾向用这后一名称. 严格地说,“自感系数”的概念只适用于似稳电路.在似稳条件下,电流密度j与磁感强度B一样,形成无散的矢量场,即电流线(管)和磁力线(管)都是闭合的.它们之中有的相互链结,有的则不然,在空间交织成复杂的图象. 如[1]所述,有横截面积的导体回路自感系数的“计算方法”(更确切地,也许应该说是“定义”)有三: (1)磁能法,即通过下式计算自感系数L;积分遍及有磁场的…     

在电磁学课程中引入磁矢势的做法和体会

在普通物理电磁学教学中，从来就重视电势与能量的讨论，一般局限于标势，对磁矢势介绍得很少．而在赵凯华，陈熙谋教授编写的《新概念物理教程》电磁学中，从磁高斯定理的积分形式出发，引入了磁矢势的概念，并且给出了计算磁矢势的一些特殊的例子．然而在课堂教学中要不要引入磁矢势，如何取材，学生能否接受，效果如何等，却是我们必须面对的问题．     

无限长载流薄板磁场的矢势与磁感应强度计算及可视化

推导了无限长均匀薄板电流磁场的矢势和磁感应强度的解析式,将公式无量纲化,计算矢势和磁感应强度,画出中垂面上和板平面上矢势和磁感应强度曲线,并与直线电流磁场的矢势和磁感应强度进行比较,画出矢势和磁感应强度两个分量以及合磁场和方向曲面,画出了二维磁感应线,显示了磁感应强度分布规律.     

利用磁矢势计算分离均匀载流薄圆筒周围的磁场强度

根据一对反平行无限长载流直导线周围等磁矢势线的特点,与分离载流薄圆筒表面的等磁矢势线进行类比,采用等效替代法方便地得到分离载流薄圆筒周围的等磁矢势线函数与磁场强度函数.     

电磁场矢势和标势的规范变换及规范不变性的一个实例

在电磁学中,当考虑由电荷电流分布激发电磁场的问题时,引入标势（？）与矢势A给求解电磁场问题带来很大的方便,且标势（？）与矢势A满足规范变换与规范不变性.近代物理学中,规范变换是作为基本方法而引入的,     

On the formation of a potential well for a nonferromagnetic conductor in a variable magnetic field

We consider the nonlinear ponderomotive effect produced by a phase shift between rapidly oscillating magnetic-field components. It is shown that the superposition of the fields leads to the formation of a potential well and to a significant increase in the force acting on a nonferromagnetic conductor.M. V. Lomonosov Moscow State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 93–98, September, 1994.     

磁矢势的边值关系和物理中的无穷大

就稳恒磁场矢势边值关系的一些意见提出质疑,肯定了正统证法的正确性.并从数学角度阐明了物理中碰到的无穷大的性质.此外对矢势切向分量的关系提出了更一般的公式,也给出了所有边值关系的数学本质.     

The premelt dynamics of an exploding conductor circuit

The system of nonlinear differential equations that model a simple exploding conductor circuit in its initial stages up to the melting point of the conductor is analyzed. Using the method of variation of parameters, approximate analytical solutions are derived that reflect the role of the circuit parameters and initial conditions in shaping the dynamics. A comparison with solutions obtained by numerical integration shows that the approximate solutions are quite accurate over the entire domain of validity of the mathematical model     

Local density of states of a three-dimensional conductor in the extreme quantum limit

The electronic structure of the narrow gap semiconductor InAs is investigated by scanning tunneling spectroscopy and magnetotransport measurements in the extreme quantum limit. The well-known oscillations of the Hall coefficient are reproduced and the last, most pronounced oscillation is shown to be correlated with the appearance of corrugations in the local density of states. While the increasing part of the Hall constant corresponds to the existence of isolated patterns indicating magnetic field induced localization, the decreasing part correlates with the development of a network which most likely consists of one-dimensional channels. We conclude that the decrease of the Hall constant in the extreme quantum limit is caused by a transition from a purely three-dimensional to a partly one-dimensional transport regime.     

The toroidal decomposition of the vector potential of a magnetic field and its applications

The toroidal (orthogonal) decomposition of the vector potential of a magnetic field is proposed. Based on this decomposition, equations of electrodynamics of non-varying and varying electromagnetic fields are derived. Applications of the developed theory to natural phenomena and laboratory experiments are discussed.     

导体对磁场的屏蔽作用分析

分析了导体球壳对静磁场和对交变磁场的屏蔽作用,讨论了影响导体球壳对静磁场和对交变磁场的屏蔽作用的因素.     

Rippled graphene in an in-plane magnetic field: effects of a random vector potential

We report measurements of the effects of a random vector potential generated by applying an in-plane magnetic field to a graphene flake. Magnetic flux through the ripples cause orbital effects: Phase-coherent weak localization is suppressed, while quasirandom Lorentz forces lead to anisotropic magnetoresistance. Distinct signatures of these two effects enable the ripple size to be characterized.     

导磁导电球体在均匀谐变磁场中产生的磁场分布规律

从求解导磁导电各向同性球体的赫兹矢量π*出发,推导出了导磁导电球体置于均匀谐变低频弱磁场中球体产生的磁场分布规律和球频率函数.