Boundary value problems of a class of nonlinear partial differential inclusions

This paper deals with the boundary value problems of nonlinear partial differential inclusions, driven by a negative Laplacian, and with the multivalued term which contains the gradient. It is proved the existence of solutions for the inclusions with the convex and nonconvex valued perturbations. The existence of extremal solutions and a strong relaxation theorem are also obtained.     

Propagation of a pair of vortices through a tilted lens

The propagation of a pair of vortices nested in a Gaussian beam through a tilted lens is studied. It is shown that after passing through the tilted lens, the relation between the transverse position of vortices and the tilt coefficient is linear in the propagation for isopolar vortex pair and vortex dipole, and in the three-dimensional (3D) case the vortex trajectories are sometimes like U or X shapes. With increasing the orientation angle of the vortex pair, the trajectories of vortices are circles for the both cases. The overlap of vortices may take place for the isopolar vortex pair, while the annihilation and revival of vortices occur for the vortex dipole in the propagation.     

Research about properties of beam optical focusing structures with double subwavelength metal slits

In this work, beam optical focusing structures capable of double side beam focusing are proposed. The relationships between focal intensity, focal length, focal width and the distance from optical source to lens structure are investigated and numerically simulated. Furthermore, a novel structure that is steadily operating in large wavelength domain is presented, whose properties are well described by comprehensive numerical simulations.     

Structure, spin reorientation and M(o)ssbauer effect studies of Tb0.3Dy0.7(Fe1-xAlx)1.95 alloys

The effect of Al substitution for Fe on crystal structure, magnetostriction and spontaneous magnetostriction, anisotropy and spin reorientation of a series of polycrystalline Tb0.3Dy0.7(Fe1-xAlx)1.95 alloys (x = 0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, 0.35) at room temperature and 77 K was investigated systematically. It was found that the primary phase of Tb0.3Dy0.7(Fe1-xAlx)1.95 is the MgCu2-type cubic Laves phase structure when x < 0.4 and the lattice constant a of Tb0.3Dy0.7(Fe1-xAlx)1.95 increases approximately and monotonically with the increase of x. The substitution of Al leads to the fact that the magnetostriction ( inceases slightly in a low magnetic field (H ≤ 40 kA/m), but decreases sharply and is easily close to saturation in a high applied field as x increases, showing that a small amount of Al substitution is beneficial to a decrease in the magnetocrystalline anisotropy. It was also found that the spontaneous magnetostriction (ζ)111 decreases greatly with x increasing. The analysis of the M(o)ssbauer spectra indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the changes of composition and temperature, namely spin reorientation. A small amount of non-magnetic phase exists for x = 0.15 in Tb0.3Dy0.7(Fe1-xAlx)1.95 alloys and the alloys become paramagnetic for x > 0.15 at room temperture, but at 77 K the alloys still remain magnetic phase even for x = 0.2. At room temperature and 77 K, the hyperfine field decreases and the isomer shifts increase with Al concentration increasing.     

PREPARATION OF ACTIVATED CARBON FIBERS AND THEIR XENON ADSORPTION PROPERTIES (I)-PREPARATION AND PORE STRUCTURE CHARACTERIZATION

1. INTRODUCTION Xenon isotopics are products of nuclear fission. The nuclear plant operation may release radioactive xenon to environment, thus result in serious damage to the environment and human health. Therefore, the adsorption and concentrating of x…     

提高双参量光纤传感器精度的一种方法

分析了光纤传感器进行双参量测量时，系数矩阵的态性对待测量精度的影响，提出采用对系数矩阵进行预处理的方法，使得处理后的矩阵由病态变成良态。用方法对文献「４」和文献「５」给出的系数矩阵分别进行了处理。处理后，文献「４」系数矩阵的条件数从３４２降低到４，文献「５」系数矩阵的条件数从１６１降低到３，传感器输出不确定主降低了两个数量级。     

Investigations on the process of dissolution and transformation of chloropinnoite in boric acid aqueous solution at 303 K by kinetics and Raman spectroscopy

Kinetics of dissolution and transformation of chloropinnoite (2MgO·2B₂O₃· MgCl₂·14H₂O) in 4.5% (wt%) boric acid aqueous solution at 303 K had been studied, and the kinetic process and mechanism were investigated by the Raman spectroscopy. According to the kinetic curve, the process of dissolution and phase transformation can be divided into three stages: dissolution stage, phase transformation induction period, and crystallization stage. The experimental results showed that when chloropinnoite dissolved in boric acid aqueous solution, MgCl₂ was removed and midproduct (MgB₂O(OH)₆·H₂O) dissolved at the same time, which was different from that of in water. Kurnakovite was a final product. The experimental data of the crystallization process have been fitted with the following mathematical modification with the aid of simplex optimum method and Runge–Kutta digital solution of differential equation system: ?dc/dt = 6.31(c?0.3906)² + 0.975(c?0.3906). Based on our experimental results and the Raman spectroscopy, kinetics and mechanism of dissolution, phase transformation, and crystallization of borate in chloropinnoite–boric acid water system are discussed. © 2005 Wiley Periodicals, Inc. Int J Chem Kinet 38: 136–143, 2006     

Structure, spin reorientation and M?ssbauer effect studies of Tb0.3Dy0.7(Fe1?xAlx)1.95 alloys

The effect of Al substitution for Fe on crystal structure, magnetostriction and spontaneous magnetostriction, anisotropy and spin reorientation of a series of polycrystalline Tb_0.3Dy_0.7(Fe_1−x Al_x)_1.95 alloys (x = 0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, 0.35) at room temperature and 77 K was investigated systematically. It was found that the primary phase of Tb_0.3Dy_0.7(Fe_1−x Al_x)_1.95 is the MgCu₂-type cubic Laves phase structure when x < 0.4 and the lattice constant a of Tb_0.3Dy_0.7(Fe_1−x Al_x)_1.95 increases approximately and monotonically with the increase of x. The substitution of Al leads to the fact that the magnetostriction λ inceases slightly in a low magnetic field (H ⩽ 40 kA/m), but decreases sharply and is easily close to saturation in a high applied field as x increases, showing that a small amount of Al substitution is beneficial to a decrease in the magnetocrystalline anisotropy. It was also found that the spontaneous magnetostriction λ ₁₁₁ decreases greatly with x increasing. The analysis of the M?ssbauer spectra indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the changes of composition and temperature, namely spin reorientation. A small amount of non-magnetic phase exists for x = 0.15 in Tb_0.3Dy_0.7(Fe_1−x Al_x)_1.95 alloys and the alloys become paramagnetic for x > 0.15 at room temperature, but at 77 K the alloys still remain magnetic phase even for x = 0.2. At room temperature and 77 K, the hyperfine field decreases and the isomer shifts increase with Al concentration increasing.     

Construction of Quasi-Periodic Breathers¶via KAM Technique

By developing a KAM theorem which involves an infinitely multiple normal frequency, it is shown that there are plenty of breathers, quasi-periodic in time and super-exponentially localized in space, for the networks of weakly coupled oscillators. This answers an open problem by Aubry [A2] in case the linearized system has no continuous spectrum. Received: 29 March 2001 / Accepted: 10 October 2001     

煤炭低位发热量快速计算新公式

本文介绍的一组计算煤炭低位发热量公式，是在收集了我国各个不同地区、不同煤种的煤样３０００多个的基础上，对其进行分类，采用回归分析的方法得到。与国内外现行公式比较，具有使用简单，计算快捷，更为精确的特点。