铁磁/有机半导体/铁磁系统的电流自旋极化性质研究

根据有机半导体中的电流自旋极化注入和输运实验现象，理论上研究了铁磁/有机半导体/铁磁系统的电流自旋极化性质.考虑到有机半导体的具体特性，从自旋扩散理论和欧姆定律出发，得到了系统的电流自旋极化率.假设自旋极化子和不带自旋的双极化子为有机半导体中的载流子.通过计算发现，极化子为实现有机半导体中电流极化注入和输运的有效自旋载流子，即使它只占总载流子很少一部分.还进一步研究了自旋相关界面电阻和电导率匹配以及有机半导体长度等因素对系统电流自旋极化的影响. 关键词： 自旋电子学 自旋注入 有机半导体 极化子     

卷云短波红外辐射特性

 采用离散纵标法耦合大气分子吸收，模拟计算了卷云大气的反射特性。研究了在短波波段卷云辐射性质随波长、卷云光学厚度、卷云有效尺度、云高和卷云中冰晶粒子形状等的变化关系，分析了卷云对大气红外背景辐射的影响。结果表明：在2.7 μm的水汽强吸收带上，卷云的出现明显增强了该波段的大气背景辐射，反射率随光学厚度和云高增大而增大。     

半圆和四分之一圆二维弹子球的量子谱分析

采用近来提出的量子谱函数,我们把闭合轨道理论应用到半圆和四分之一圆弹子球系统,这种量子谱函数的傅利叶变换包含了连接任意两点的许多经典轨道的信息.计算表明量子谱的傅立叶变换和经典轨道的长度符合的很好.从这两个体系可以看出半经典理论为经典和量子力学提供了很好的桥梁作用.     

The separation of out-of-plane displacement from in-plane components by fringe carrier method based on large image-shearing ESPI

A fringe carrier method for separating out-of-plane displacement from in-plane components based on large image-shearing electronic speckle pattern interferometry (ESPI) is presented. If the test object is respectively illuminated by two expanded symmetric illuminations in large image-shearing ESPI, two interferometers are formed. Carrier fringe patterns can be introduced by tilting reference surface a small angle. The carrier fringe patterns are demodulated after deformation of the object. Two phase maps, which include out-of-plane and in-plane displacement, can be obtained by using Fourier transform. Then out-of-plane displacement can be easily separated from in-plane displacement by simple operation between two unwrapped phase distributions. The principle of spatial carrier frequency modulation in large image-shearing ESPI is discussed. A typical three-point-bending experiment is completed. Experimental results are offered. The results show that the method offers high visibility of carrier fringes. And the system presented does not need a special beam as a reference light and has simple optical setup.     

Fresnel diffraction of truncated Gaussian beam

We study the Fresnel diffraction of Gaussian beam truncated by one circular aperture, and give the general analytic expression of the Fresnel diffraction of truncated Gaussian beam denoted by Bessel functions. Then the characteristic of the axial diffraction fluctuation and the influence of the caliber of the circular aperture and the wave waist of Gaussian beam on the diffraction distributions are discussed, respectively. Through the numerical calculations, the characteristics of the transverse diffraction are presented and the relationship of the fluctuation of the transverse diffraction profile and the position of the axial point is shown. The physical origin of the fluctuation of Fresnel diffraction intensities of truncated Gaussian beam is expressed in terms of Fresnel half-zone theory. These phenomena and the conclusions are important for the measurement of the parameters of the beam and its applications.     

4 ,4′-二巯基二苯醚分子的电子输运性质研究

利用从头算方法和弹性散射格林函数理论,研究了4 ,4′-二巯基二苯醚分子的电输运性质.计算表明,当外加偏压少于0 .9 V时,该分子器件不导电.当外加偏压进一步增加时,该分子器件的电导呈现出平台特征.由于中间氧原子的存在,相对于4 ,4′-二巯基联苯分子来说,该分子的导电特性较差.     

高碘酸钾法测钢铁及合金中锰的改进建议

试样经酸溶解后,以磷酸-高氯酸混合酸(4 1)或(9 1)氧化至冒烟.在硫酸、磷酸介质中,用高碘酸钾将锰氧化到七价,测其吸光度.     

COD速测仪测定工业废水中CODCr

采用标准回流法和仪器法（用ＣＯＤ速测仪）对工业废水化学需氧量进行对照测定，结果发现，用ＣＯＤ速测仪测定工业废水，简便、快速、精密度好、准确度高。     

The construction of Lyapunov functions with sign-definite derivative for systems satisfying the Barbashin–Krasovskii theorem

The asymptotic stability of the zero solution of autonomous systems of differential equations is considered. For systems satisfying the Barbashin–Krasovskii theorem positive-definite functions are constructed having a negative-definite derivative. The investigation is based on the method of invariant relations.     

The impact of other-regarding tendencies on the spatial vaccination game

Using the evolutionary game framework to describe the vaccination behaviors of individuals, this work focuses on the impact of other-regarding tendencies on collective decision-making of vaccination. With extensive computational simulations, we find that when the vaccination cost is small or moderate, the variance of vaccination coverage as well as epidemic size is monotonically depending on the other-regarding effect. However, with a high price of vaccine, a moderate deviation from being entirely self-centered results in a poor communal vaccination benefit. In addition, we also find that the other-regarding effect may lead to an optimal total social cost.