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1.
谭康伯  路宏敏  苏涛 《物理学报》2018,67(20):209401-209401
基于系统性电磁兼容的考虑,对等离子环境中在轨航天器导体充放电现象中的能量特征进行了变分研究.通过电磁Collin原理,对等离子环境中导体系统几何尺度与所带电能的变分联系进行了理论分析.在此基础上,推广了更具一般性的数值估值分析方法,并对复杂导体系统电磁参数、等离子环境特征与系统能量间的关系进行了实例分析.研究结果对于等离子环境中复杂带电体的能量控制及相关的电磁环境效应与防护等研究具有积极意义.  相似文献   

2.
由矢势分析了"三维导体"的自感电动势,利用■=L︳I/t︳给出了"三维导体"无限长同轴电缆的自感系数.直观地说明了自感的成因.  相似文献   

3.
以圆盘电容为参照,从等值电容的角度研究孤立导体平板电容的近似计算,并给出了一些计算实例。  相似文献   

4.
曹鹤飞  刘尚合  孙永卫  原青云 《物理学报》2013,62(14):149402-149402
航天器内部孤立导体充放电对航天器的影响更为隐蔽, 造成直接和潜在的伤害更加严重. 综合考虑航天器内部环境中粒子参数及材料二次电子特性等因素, 基于气体动理论, 结合粒子的麦克斯韦速度分布函数, 得出孤立导体球充电电位一般表达式. 利用电位表达式推导得出孤立导体球净电荷量及静电场能量与导体面积关系表达式. 讨论了特殊情况下孤立导体静电场能量与面积及空间环境的关系, 与地面电子元器件电磁脉冲放电损伤值进行了对比, 总结出孤立导体表面带电面积效应规律. 关键词: 孤立导体 表面带电 静电场能量 面积效应  相似文献   

5.
电容是导体的一个重要特征,是表示导体容纳电荷多少的物理量.孤立导体的电容就是远离其他物体的导体的电容.对于孤立导体,公式(如球形孤立导体的电位U=Q/4πεR),和实验结果说明,导体所带的正电荷越多,其电位越高(本文以导体带正电为例进行讨论).那么.是不是导体电位的高低由带电荷的多少来决定呢?  相似文献   

6.
曹鹤飞  刘尚合  孙永卫  原青云 《物理学报》2013,62(14):149401-149401
航天器在等离子体环境下的表面充放电受到多种因素影响, 其中充电时间是影响静电放电频次的一个重要因素. 本文从等离子体的微观结构出发, 同时考虑材料参数特性, 在对每个粒子运用力学原理的基础上, 以统计方法 推导出孤立导体球表面充电电位时域表达式. 利用电位时域表达式推导出孤立导体球净电荷量时域表达式及静电场能量时域表达式. 以较低非极地地球轨道和较高地球同步轨道为例对孤立导体球电位、 净电荷量及静电场能量的时域特性进行了讨论, 分析了空间环境参数和导体球半径大小对表面充电的影响, 总结出等离子体环境下孤立导体表面充电时域特性规律. 关键词: 等离子体 孤立导体 表面带电 时域  相似文献   

7.
严雪飞 《大学物理》2011,30(3):44-47
推广了一般导体和点电荷电像,用迭代电像法计算了两个导体球之间的作用力与电容,并做了推广以及精确性分析.进一步给出了多个导体球的一般计算方式.作为多导体球问题的例子给出了第三个无静电荷的导体球对两导体球体系的影响.给出了导体作用数值计箅的具体方式,并且为导体相互作用实质提供了清晰的物理图像.  相似文献   

8.
电导率是表示导体导电能力强弱的度量,离子导体的电导率可以通过平均漂移速度求得.文中通过对离子导体的分析,给出一种基于熵的新的推导方法.首先分析系统熵和环境熵的竞争关系,其次运用熵最大原理求出最概然电流,进而导出电导率公式.最后将基于熵的推导方法与漂移速度方法加以区别和对比,并推广到一般导体电导率公式的推导.  相似文献   

9.
在"电场中的导体"这部分内容的教学过程中,常遇到这类问题: [问题1]如图1所示,在孤立的正电荷Q的电场中放入不带电的金属导体棒AB后,将B端接地后又拆去接地线,最后移开Q,问AB棒带何种电荷?  相似文献   

10.
两个接触球孤立导体   总被引:1,自引:0,他引:1  
童国平 《大学物理》1991,10(8):13-14,F003
本文利用电象法研究了两个接触球孤立导体的电容、电势及面电荷密度分布,并对所得结果进行了一些讨论.  相似文献   

11.
The variety of bi-confluent Heun potentials for a stationary relativistic wave equation for a spinless particle is presented. The physical potentials and energy spectrum of this wave equation are related to those for a corresponding Schrödinger equation in the sense that all the potentials derived for the latter equation are also applicable for the wave equation under consideration. We show that in contrast to the Schrödinger equation the characteristic spatial length of the potential imposes a restriction on the energy spectrum that directly reflects the uncertainty principle. Studying the inversesquare- root bi-confluent Heun potential, it is shown that the uncertainty principle limits, from below, the principal quantum number for the bound states, i.e., physically feasible states have an infimum cut so that the ground state adopts a higher quantum number as compared to the Schrödinger case.  相似文献   

12.
We show that techniques suitable for studying the bound state problem for the linear Schrödinger equation are also applicable to certain nonlinear generalizations. A sufficient condition for the absence of bound states and a family of lower bounds on the eigenvalues are derived.  相似文献   

13.
We prove two bounds on the value of renormalized Euclidean Feynman graphs. One is a relatively crude but widely applicable bound; the other a finer bound applicable to 4 4 -like models.  相似文献   

14.
It is shown that the potential perturbation that shifts a chosen standing wave in space is a block of potential barrier and well for every wave bump between neighbouring knots. The algorithms shifting the range of the primary localization of a chosen bound state in a potential well of finite width are as well applicable to the scattering functions if states of the continuous spectrum are considered as bound states normalized to unity but distributed on an infinite interval with vanishing density. The potential perturbations of the same type on the half-axis concentrate the scattering wave at the origin, thus creating a bound state embedded into the continuous spectrum (zero width resonance).  相似文献   

15.
场协同理论在脉管制冷机研究中的推广   总被引:2,自引:1,他引:1  
本文采用理论分析和数值计算的方法,确认由过增元教授等提出的强化换热的场协同理论同样可以应用到能量转换过程。文中用场协同理论揭示了脉管制冷机发展过程中几次重大改进的实质,并以此理论指导改进脉管制冷机的结构参数,发现了脉管的最佳长径比。  相似文献   

16.
An iterative method of solution of the Lippmann-Schwinger-type equation is proposed. This method is applicable to the bound state energy calculations of strongly coupled particles and can also be applied to the Faddeev equations. The convergence of this method is tested on the Lippmann-Schwinger equation.  相似文献   

17.
The tunnel ionization, induced by a weak electrostatic field, of a particle bound in an attractive one-dimensional power-law singular potential is analysed. An accurate approximation applicable for the general case of non-fractional power exponent is suggested.  相似文献   

18.
开关型霍尔传感器的原理与工程实现   总被引:3,自引:1,他引:2  
介绍了开关型霍尔传感器的工作原理,设计了适用于工程测量的具体线路,并分析了该线路的特点。  相似文献   

19.
We use quasiparticle tunneling across La2-xCexCuO4 grain boundary junctions to probe the superconducting state and its disappearance with increasing temperature and magnetic field. A zero bias conductance peak due to zero energy surface Andreev bound states is a clear signature of the phase coherence of the superconducting state. Hence, such a peak must disappear at or below the upper critical field Bc2(T). For La2-xCexCuO4 this approach sets a lower bound for Bc2(0) approximately 25 T which is substantially higher than reported previously. The method of probing the superconducting state via Andreev bound states should also be applicable to other cuprate superconductors.  相似文献   

20.
In order to alter a typical molecular aptamer beacon (MAB) to detect a different analyte there is currently a need to change the whole sensor unit including the expensive labeling fluorophores. In this work a DNA-based reconfigurable molecular aptamer beacon was developed. It is composed of two parts: a variable part and a constant part. The variable part comprises an aptamer strand and its complementary strand while the constant part is an oligonucleotide doubly labeled with a Förster Resonance Energy Transfer (FRET) pair and the two parts become joined via DNA hybridization. The sensor exists in two conformations: a folded (high FRET) and an unfolded (low FRET) in the absence and presence of the aptamer-target binding respectively. This sensor can be reconfigured by washing away the aptamer and the complementary strand using proper complementary strands, called washers. As a proof of the principle, a sensor that bound the enzyme thrombin, an analyte with a strong binding, was first constructed and then reconfigured to bind adenosine, selected as an analyte with a weak binding. We believe that the design is of universal use applicable to many types of aptamers.  相似文献   

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