Variable separation solutions and new solitary wave structures to the (1+1)-dimensional equations of long-wave－short-wave resonant interaction

A variable separation approach is proposed and extended to the (1+1)-dimensional physical system. The variable separation solutions of (1+1)-dimensional equations of long-wave－short-wave resonant interaction are obtained. Some special type of solutions such as soliton solution, non-propagating solitary wave solution, propagating solitary wave solution, oscillating solitary wave solution are found by selecting the arbitrary function appropriately.     

Bound states of two-dimensional relativistic harmonic oscillators

We give the exact normalized bound state wavefunctions and energy expressions of the Klein－Gordon and Dirac equations with equal scalar and vector harmonic oscillator potentials in the two-dimensional space.     

Using symbolic computation to construct travelling wave solutions to nonlinear partial differential equations

Based upon the symbolic computation and the coupled projective Riccati equation, the tanh function method is further improved. As its applications, Wu－Zhang equation (which describes a (2+1)-dimensional dispersive long wave) and the (1+1)-dimensional dispersive long wave equation obtained from Wu－Zhang equation by scaling transformation and symmetry reduction are chosen to illustrate the validity of the proposed approach.     

Analytical model of electron transport characteristics for 4H-SiC material and devices

Based on 4H-SiC material parameters, three different analytical expressions are used to characterize the electron mobility as the function of electric field. The first model is based on simple saturation of the steady-state drift velocity with electric field (conventional three-parameter model for silicon). The second GaAs-based mobility model partially reflects the peak velocity in high electric fields. The third multi-parameter model proposed in this paper is more realistic since it well reproduces the drift velocity－field characteristics obtained by Monte Carlo calculations, revealing the peak drift velocity with subsequent saturation at higher electric fields. Thus, the drift velocity model presented in this paper is much better for device simulation. In this paper, the influence of mobility model on DC characteristics of 4H-SiC MESFET is calculated and the better accordance with the experimental results is presented with multi-parameter model.     

Effect of adiabatic variation of dust charges on dust acoustic solitary waves in magnetized dusty plasmas

The effect of dust charging and the influence of its adiabatic variation on dust acoustic waves is investigated. By employing the reductive perturbation technique we derived a Zakharov－Kuznetsov (ZK) equation for small amplitude dust acoustic waves. We have analytically verified that there are only rarefactive solitary waves for this system. The instability region for one-dimensional solitary wave under transverse perturbations has also been obtained. The obliquely propagating solitary waves to the z-direction for the ZK equation are given in this paper as well.     

A SENSITIVE AND STABLE CONFOCAL FABRY－PéROT INTERFEROMETER FOR SURFACE ULTRASONIC VIBRATION DETECTION

A new confocal Fabry－Pérot interferometer (CFPI) has been constructed. By using both of the conjugate rays, the sensitivity of the system was doubled. Moreover, the negative feedback control loop of a single-chip microcomputer (MCS-51) was applied to stabilize the working point at an optimum position. The system has been used in detecting the piezoelectric ultrasonic vibration on the surface of an aluminium sample.     

Bound states of the Klein－Gordon and Dirac equations for potential V(r)=Ar-2-Br-1

The exact normalized bound-state wavefunctions and energy equations of Klein－Gordon and Dirac equations are given with equal scalar and vector potentials s(r)=v(r)=V(r)/2=(Ar^-2-Br^-1)/2.     

Effects of Acetone,Ethanol, Isopropanol and Dimethyl Sulfoxide on Amylose-Iodine Complex†

Abstract

The amylose-iodine (AI) complex formation was studied by absorption spectra in water and water-containing varying proportions of ethanol, acetone, isopropanol and dimethyl sulfoxide (DMSO). Complex formation is most favored in pure water and decreases as the proportion of nonaqueous solvent is increased. A decrease in the absorbance intensity at around 615 nm (for AI complex) is accompanied by a peak shift towards 550 nm and an increased absorbance at around 350 nm (for unbound iodine). The amount of the nonaqueous solvent added, as well as the order in which it is added relative to amylose and iodine solution; change remarkably the extent of the AI complex formation. A mechanism of the complex formation is proposed.

     

Effects of Acetone,Ethanol, Isopropanol,and Dimethyl Sulfoxide on Amylose-Iodine Complex

ABSTRACT

The amylose-iodine (AI) complex formation was studied by absorption spectra in water and water containing varying proportions of ethanol, acetone, isopropanol and dimethyl sulfoxide (DMSO). Complex formation is most favored in pure water and decreases as the proportion of nonaqueous solvent is increased. A decrease in the absorbance intensity at around 615 nm (for AI complex) is accompanied by a peak shift towards 550 nm and an increased absorbance at around 350 nm (for unbound iodine). The amount of the nonaqueous solvent added, as well as the order in which it is added relative to amylose and iodine solution, change remarkably the extent of the AI complex formation. A mechanism of the complex formation is proposed.     

BaCe0.5Zr0.4La0.1O3－α陶瓷的制备及其电性能

以高温固相反应法合成了BaCe0.5Zr0.4La0.1O3－α陶瓷. 粉末XRD结果表明, 该陶瓷材料为单一钙钛矿型BaCeO3斜方晶结构, 在高温下、CO2或水蒸气气氛中具有较高的稳定性. 以陶瓷材料为固体电解质、多孔性铂为电极, 用交流阻抗谱技术测定了材料在500～900 ℃下, 不同气体气氛中的电导率; 用气体浓差电池方法测定了材料在干燥空气、湿润空气和湿润氢气气氛中的离子迁移数, 研究了材料的离子导电特性. 结果表明, 在500～900 ℃下, 干燥或湿润的气体气氛中, 随着温度升高和氧分压增大, 材料的电导率均增大. 在干燥空气中, 陶瓷材料的氧离子迁移数为0.685～0.147, 是一个氧离子与电子空穴的混合导体. 在湿润空气中, 陶瓷材料的质子迁移数为0.001～0.006, 氧离子迁移数为0.618～0.164, 是一个质子、氧离子和电子空穴的混合导体. 在湿润氢气中, 500～700 ℃温度范围内, 陶瓷材料的质子迁移数为1, 是一个纯的质子导体; 而在800～900 ℃温度范围内, 陶瓷材料的质子迁移数为0.957～0.954, 是一个质子与电子的混合导体, 质子电导占主导.