非平衡磁控溅射系统磁场的半解析法

应用电磁场分析中的一种新方法——半解析法，对一种典型的非平衡磁控溅射系统进行了磁场分析. 结果表明，应用半解析法计算,求解变量少、方法简单，而且计算精度高，该方法相对于等效源法有严密的理论依据，标量位函数的表达式为级数解析式，有利于场强的计算，更有利于优化设计.     

非平衡磁控溅射系统磁场的半解析法

应用电磁场分析中的一种新方法——半解析法,对一种典型的非平衡磁控溅射系统进行了磁场分析. 结果表明,应用半解析法计算,求解变量少、方法简单,而且计算精度高,该方法相对于等效源法有严密的理论依据,标量位函数的表达式为级数解析式,有利于场强的计算,更有利于优化设计. 关键词： 非平衡磁控溅射 半解析法 标量磁位 磁场强度     

静电偏转型摄像管聚焦偏转系统设计Ⅰ-场的计算

磁聚焦静电偏转(MS)和静电聚焦静电偏转(SS)型摄像管具有图像失真小,分辨率高且均匀,电子束易于垂直上靶,阴影小等优点,所以受到人们的重视。但图案偏转电极的形状复杂,非对称场的计算较困难。本文对静电偏转型聚焦偏转系统的结构作了分析研究,远用分离变量法给出了圆柱坐标中静电聚焦(旋转对称)场和静电偏转(非旋转对称)场的解析解,并给出了计算实例。     

脉冲涡流检测瞬态涡流场的时域解析模型

应用Laplace反变换技术建立脉冲涡流检测瞬态涡流场的时域解析模型.首先,基于电磁波的反射与透射理论,应用截断区域特征函数展开式法建立瞬态涡流场的复频域模型,然后通过求解模型极点及其留数应用部分分式展开法求解复频域模型的Laplace反变换,从而建立阶跃型和指数型电流激励下瞬态涡流场的时域解析模型.所建模型具有实现简单、效率高、模型精度不受吉布斯效应影响等优点.最后应用基于Fourier反变换的探头瞬态感应电压模型对本文所建模型,实验结果验证了本文所建模型的正确性.     

线极化摇摆场中的束流动力学

对线极化摇摆场中,在有引导磁场或四极磁场时的电子轨迹特性、束流包络特性进行了解析分析和数值分析,推得了线极化摇摆场中的梯度漂移解析表达式,借助于Bogoliubov的非线性渐近法和奇异摄动法得到的解析分析结果与数值分析结果很好地吻合。     

谐振腔链色散关系及场分布的解析研究

从圆柱坐标系下的Borgnis位函数的齐次标量Helmholtz方程出发,引入慢波驻波概念及其场 表达式,利用Borgnis位函数的边界条件及相邻子区公共界面上的场匹配条件,导出了整腔 结尾的谐振腔链内角向均匀TM模的色散关系及场分布的解析表达式.运用该解析法对实际器 件——四腔渡越管振荡器进行了求解,求得的谐振频率与实验中测得的微波频率一致,求得 的场分布与数值法得到的场分布十分符合. 关键词： 谐振腔链 色散关系 场分布 解析法     

实际大气中平面波声场的计算

本文应用先前工作中关于运动分层介质中平面波反射和折射的一般理论,来解决实际大气中声场的问题。提出计算存在温度梯度和风梯度的多层大气中声场的解析法和图解法。前者给出声场WKB近似及其各次修正项的级数表达式,后者给出直观的图象表示。这些结果具有明晰的物理意义,并且在大多数情形下都可以通过简单的计算得到具体结果,同时也可以作为进一步进行数值计算的基础,这比用直接的数值法求解要简捷得多。     

高压脉冲电场保鲜技术中两半圆柱面形电极的电场分布

高压脉冲电场保鲜技术是利用强电场进行杀菌，可以在不破坏食品的营养结构与原有风味的基础上起到杀菌保鲜作用．实验表明，杀菌的效果与电场有关，本文求出了两半圆柱面形电极间的场强分布，对实验将具有指导作用。     

确定微型圆柱腔回音廊模式共振峰位置的方法

本文介绍了微型圆柱腔中回音廊模式共振峰位置的两种确定方法,即数值计算法和解析近似公式求解法。用两种方法对回音廊模式的共振峰位置进行了计算比较,结果表明:精确的数值计算结合简便的解析近似公式求解方法,为快速、精确地确定回音廊模式的共振峰位置提供了一种方便和可靠的途径。     

对称場的測定——电解槽模拟法

一、引言在电子器件中,要想知道电极系统的光学性质,就必须知道电子在给定电极系统的场中的运动轨迹;为了求得电子的运动轨迹,就必须首先知道场的分布。因此对任何电子光学系统的理论研究或实验工作,都必须从确定该系统的场的分布开始,在关于确定已知电极的形状、大小及其上所加的电压或磁极的形状、大小及安培匝数的场的分布情况,目前有三种方法:(a)解析法。这种方法是用解析函数来表达场,故最精确;但并不是所有的情况都可以应用,它仅能在少数比较简单的系统的条件下才可以写出解析函数,故在解决实际问题上应用不广。(b)数值计算法。这种方法具有实用意义,在原     

Design of correction electrodes for high-voltage vacuum-dielectricinterfaces

High-voltage vacuum insulators often set the limits on energy transfer in pulsed power systems. The ideal vacuum interface has a uniform electric field distribution on the insulator well below breakdown levels and an impedance matched to the pulse generator. This paper describes a procedure to design correction electrodes for the dielectric region of a cylindrical interface using a numerical field solution code. The approach has application to both pulsed and steady-state systems. The method is illustrated with a design for a 10 TW, 6.5 MV pulsed power generator using six correction electrodes. The design minimizes the interface impedance and gives less than 10% field variation along the insulator surface     

兰州彭宁阱核心电极的最优电压幅值计算

彭宁阱是用于直接测量原子核质量的精确设备。为了保证彭宁阱的测量精度,需在阱中心产生精准的四极静电场,而四极静电场是通过对彭宁阱的核心电极施加合适的电压产生的。采用公式推导法和最小二乘法两种方法计算得到了LPT核心电极需加电压幅值。对于公式推导法,电压值完全从理论出发,经公式推导后计算得到;最小二乘法的出发点是使取样偏差的平方和最小,且通过仿真模拟考虑了电极的实际几何形状。由这两种方法得到的非四极项系数C4 和C6,可用于估算因偏离理想四极电场所产生的实验误差。虽然这两种方法的出发点不同,但都可以在阱中心产生需要的四极电场。Penning trap mass spectrometry is one of the direct methods and maybe the most accurate tool for atomic mass measurements. The quadrupole electric eld produced in the trap should be very accurate in order to ensure the precision of measurements. The optimal amplitudes for the key electrodes of the Lanzhou Penning Trap(LPT) have been calculated by two methods|formula derivation and least-squares tting. For formula derivation method, the optimal values are based on the theory and deduced from the formulas. Least-squares tting method is to minimize the quadratic sum of sampling deviations, where the actual geometry of the electrodes has been considered by the simulation. The obtained C4 and C6 values can be used to estimate the experimental error produced by the deviation from the ideal quadrupole electric eld. The expected quadrupole electric led could be gotten by both methods.     

Breakdown in the transverse magnetic field

The breakdown between coaxial cylindrical electrodes in the homogeneous axial magnetic field in the pressure range around the Paschen minimum is studied. On the right of this minimum the breakdown voltage is not practically influenced by a weak magnetic field. On the left of this minimum the breakdown U-B curves can be divided into two branches: the upper ones can be approximated by the magnetron cut-off parabola, the lower ones correspond qualitatively in some cases to the second solution of the equation for breakdown in the inhomogeneous electric field corrected with respect to the losses of electrons caused by recapturing on the cathode.     

Axially symmetrical stresses measurement in the cylindrical tube using DIC with hole-drilling

In this paper, a new method combining the digital image correlation (DIC) with the hole-drilling technology to characterize the axially symmetrical stresses of the cylindrical tube is developed. First, the theoretical expressions of the axially symmetrical stresses in the cylindrical tube are derived based on the displacement or strain fields before and after hole-drilling. Second, the release of the axially symmetrical stresses for the cylindrical tube caused by hole-drilling is simulated by the finite element method (FEM), which indicates that the axially symmetrical stresses of the cylindrical tube calculated by the cylindrical solution is more accuracy than that for traditionally planar solution. Finally, both the speckle image information and the displacement field of the cylindrical tube before and after hole-drilling are extracted by combining the DIC with the hole-drilling technology, then the axially symmetrical loading induced stresses of the cylindrical tube are obtained, which agree well with the results from the strain gauge method.     

超越曲面电极结构电光偏转器研究

采用有限元法对几种不同电极结构下电光偏转器的电场分布进行研究.设计出一种具有较大偏转角度的超越曲面电极结构电光偏转器，与圆柱电极结构和双曲面电极结构电光偏转器的性能对比，可知此种电光偏转器的偏转角度更大，电场梯度线性度更高.     

Spatial harmonics of the field in a quadrupole mass filter with circular electrodes

The amplitudes of the spatial harmonics of the field are calculated for given displacements of the electrodes in a quadrupole mass filter relative to their optimum positions. The cases of radial and angular displacements of the electrodes, asymmetries in voltage supplied to the electrodes, and nonidentical rod diameters are considered. These data are required for calculating the actual shape of the mass peaks and will be useful in designing mass filters. Zh. Tekh. Fiz. 69, 96–101 (October 1999)     

Field-cycling method with central transition readout for pure quadrupole resonance detection in dilute systems

We present a modification of a field-cycling method which uses the NMR signal of the central transition at high field to indirectly detect zero-field quadrupole transitions. The quadrupole transitions at zero-field are detected as changes in the overall intensity of the central transition signal after the field cycle, and the method is relatively immune to lineshape distortions of the central transition caused by receiver dead time, frequency response of the probe, longer pulse lengths, etc. Cross-polarization with protons is used to enhance the central-transition signal and to increase the recycling rate of the experiment. The technique is especially useful when mixtures of several species are present. In a frozen solution of phenylboronic acid, 11B quadrupole signals of the tetrahedral species at 600 kHz and planar-trigonal species at 1450 kHz are clearly resolved. The field-cycling approach allows high-sensitivity detection of low-frequency quadrupole transitions; the experiment is sensitive enough to study boronic-acid protease inhibitors bound to proteins and may possibly be extended to lower sensitivity nuclei. The experiments are performed using a low-temperature field-cycling apparatus, operated at 10-30 K, capable of pneumatically moving the sample from the high field of a commercial 500 MHz magnet to the area above the top of the magnet where the low field is controlled by a pair of Helmholz coils.     

Exterior and interior metrics with quadrupole moment

We present the Ernst potential and the line element of an exact solution of Einstein’s vacuum field equations that contains as arbitrary parameters the total mass, the angular momentum, and the quadrupole moment of a rotating mass distribution. We show that in the limiting case of slowly rotating and slightly deformed configuration, there exists a coordinate transformation that relates the exact solution with the approximate Hartle solution. It is shown that this approximate solution can be smoothly matched with an interior perfect fluid solution with physically reasonable properties. This opens the possibility of considering the quadrupole moment as an additional physical degree of freedom that could be used to search for a realistic exact solution, representing both the interior and exterior gravitational field generated by a self-gravitating axisymmetric distribution of mass of perfect fluid in stationary rotation.     

Electric Field-Induced Fluid Velocity Field Distribution in DNA Solution

We present an analytical solution for fluid velocity field distribution of polyelectrolyte DNA. Both the electric field force and the viscous force in the DNA solution are considered under a suitable boundary condition. The solution of electric potential is analytically obtained by using the linearized Poisson-Boltzmann equation. The fluid velocity along the electric field is dependent on the cylindrical radius and concentration. It is shown that the electric field-induced fluid velocity will be increased with the increasing cylindrical radius, whose distribution also varies with the concentration     

Diffraction of a convergent sound wave by an elastic cylindrical shell with a longitudinal fixation

The problem of the diffraction of a zero-order convergent cylindrical wave by a cylindrical shell with a longitudinal fixation along one of its generatrices is considered. The problem is solved on the basis of using the so-called helical waves, which are aperiodic eigensolutions to the equations of the shell motion. The diffraction field is represented in the form of a convergent series in cylindrical harmonics. The method of the solution allows for a generalization to several cases of longitudinal fixation with conditions of different forms. The calculation of the scattering amplitude of the diffraction field is carried out for various frequencies and shell parameters.