Estimation of the degree of asphericity of a glass sphere using a vectorial shearing interferometer

The degree of asphericity is estimated by determining the average radius of curvature in different sections, at various points on the surface of a sphere, and the deviation from it. We employ the vectorial shearing interferometer (VSI) as the instrument to determine the radius of curvature from two subapertures of the transparent glass sphere. We incorporate the sphere as a thick lens into the interferometric setup, illuminating it with an expanded beam. The spherical aberration, introduced by the sphere in the wave front, depends on the local sphere radius, on the refraction index of the glass, and on the cone angle of the source. The wave front aberrated by the sphere impinges on the VSI. Here, the wave front is divided in two in amplitude, it is sheared vectorially, and it is superimposed with itself. The fringe pattern is formed in the intersection of the wave fronts. The shape of the resulting fringe pattern is directly related to spherical aberration. We estimate qualitatively the degree of asphericity, comparing the phase gradients in different sections of the sphere. Here, we report on the experimental setup to test the asphericity, the results with different vectorial shearing (magnitude and direction). Finally, we perform a comparison with the theoretical predictions.     

Existence of kink and unbounded traveling wave solutions of the Casimir equation for the Ito system

This paper study the traveling wave solutions of the Casimir equation for the Ito system. Since the derivative function of the wave function is a solution of a planar dynamical system, from which the exact parametric representations of solutions and bifurcations of phase portraits can be obtained. Thus, we show that corresponding to the compacton solutions of the derivative function system, there exist uncountably infinite kink wave solutions of the wave equation. Corresponding to the positive or negative periodic solutions and homoclinic solutions of the derivative function system, there exist unbounded wave solutions of the wave function equation.     

Equation of motion for a radiating charged particle in classical electrodynamics

We propose classical equations of motion for charged particles in an electromagnetic field. These are general formulas for the particle acceleration that take the radiation-induced deceleration into account and contain no second derivatives of the particle velocity. In several particular cases considered, the new equations yield results coinciding with those known in the literature and experimentally verified. We show that in the range of ultrahigh energies, classical electrodynamics does not lead to inherent inconsistencies and in principle allows particle motion with energies exceeding the Pomeranchuk limit.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 143, No. 1, pp. 112–130, April, 2005.     

极谱催化波测定脉络宁口服液中的肉桂酸

应用线性扫描极谱法(LSV)、循环伏安法(CV),在1.0 mol/L HAc-NaAc(pH 4.1)含溶解氧的支持电解质中,对肉桂酸的电化学行为进行了研究。在该支持电解质中于-1.50 V(vs.SCE)处发现肉桂酸产生一灵敏的催化极谱还原峰,其峰电流与肉桂酸的浓度在2.5×10-6~7.5×10-4mol/L范围内呈良好的线性关系(r=0.999 1);检出限为8.0×10-7mol/L,对8.0×10-5mol/L的肉桂酸溶液进行11次平行测定,RSD为1.4%。并采用循环伏安法对肉桂酸的电极反应机理进行了探讨,结果表明该电极反应过程为不可逆过程。该方法已用于测定脉络宁口服液中的肉桂酸。     

纳米Zn-Co铁氧体的固相合成及电磁损耗特性研究

采用NH₄HCO₃与FeCl₃·6H₂O，Zn(NO₃)₂·6H₂O，Co(NO₃)₂·6H₂O进行室温固相反应制得前驱物，经微波加热处理后，进而热分解分别制得复合氧化物ZnFe₂O₄、CoFe₂O₄和Co_0.5Zn_0.5Fe₂O₄。由激光粒度分析仪、XRD和SEM表征：获得了颗粒分布比较均一、平均粒度为65 nm左右、立方晶系尖晶石结构的纳米铁氧体粉体。经测试样品的相对介电常数和相对磁导率后，研究了它们的电磁损耗特性。结果表明：Co_0.5Zn_0.5Fe₂O₄在100～1 800 MHz内比另外两种铁氧体具有更好的电磁损耗特性。     

带开口磁环的周期永磁聚焦系统的2维模拟

 由于目前常用的磁聚焦系统设计方法不能直接计算带有非轴对称开口磁环的磁系统,因此在行波管磁系统实验测试基础上,提出了双面带极靴的开口磁环体积等效概念：将开口磁环等效为相等体积磁性材料的2维轴对称磁环,两者都双面带极靴时轴上的磁场值相等。使用2维电磁计算软件FEMM计算了采用该等效模型后的周期磁聚焦系统的轴上磁场值,计算结果与带有开口磁环的实际系统测试值符合良好,两者相差仅3×10^-3 T。该2维等效模型能代替开口磁环进行计算。     

Nonlinear wave interactions in patterned Silica and AlGaAs waveguides

We study nonlinear interactions between discrete optical solitons that propagate in different regimes of diffraction, and the nonlinear scattering of dispersive waves by local optical potentials. It is well known in optics that when linear coherent waves meet, they interfere without interactions. Linear waves also scatter through local optical structures not exchanging any power with the guided modes of these structures. As a focusing Kerr nonlinearity is present, such linearly-inhibited phenomena can exist. Our studies are performed in silica and AlGaAs nonlinear waveguides, excited by ultra-short pulses in the near infrared. Presented at 9-th International Workshop on Nonlinear Optics Applications, NOA 2007, May 17–20, 2007, Świnoujście, Poland     

THz波的产生及探测技术

THz技术是20世纪90年代发展起来的一门新兴学科,本文较为详细地介绍了目前产生THz波的主要方法、原理以及探测THz波的主要手段和机理.     

高阶非线性薛定谔方程的一个新型孤波解

给出了高阶非线性薛定谔方程的一个新型孤波解, 该解描述了满足一定参数条件时光纤中超短光脉冲的传输, 解的表达式可以表示为亮孤子和暗孤子和的形式. 同时利用分步傅里叶方法在一定微扰条件下对脉冲传输进行了数值模拟.     

麦迪霉素-H2O2缔合/平行催化氢波的研究及其应用

报道了有机化合物极谱催化波的一种新类型--缔合/平行催化氢波.研究麦迪霉素-H₂O₂体系缔合/平行催化氢波的结果表明,质子化麦迪霉素与H₂O₂形成缔合物,引起峰电位负移;麦迪霉素催化氢波被H₂O₂还原中间产物羟基自由基进一步催化,使峰电流显著增加.求得麦迪霉素-H₂O₂缔合物的缔合比为1:1,表观缔合常数为7.18.在0.15 mol·L^-1 KH₂PO₄-NaOH (pH 7.4)-0.02 mol·L^-1 H₂O₂支持电解质中,-1.59 V (vs. SCE)处的缔合/平行催化氢波二阶导数峰峰电流与麦迪霉素浓度在2.0×10^-8～1.0×10^-5 mol·L^-1范围内呈线性关系,检测限为6×10^-9 mol·L^-1.与麦迪霉素的催化氢波相比,该缔合/平行催化氢波提高分析灵敏度两个数量级.