飞秒脉冲的远场反射谱特性

从平面波的角谱表示出发,得到了超短脉冲光束由分层介质表面反射的频谱特性,数值计算给出了飞秒高斯脉冲经自由空间中介质薄膜反射的远场谱分布.由于光与介质的相互作用,反射谱呈现谱线变窄、红移、蓝移以及出现旁瓣而分裂成多重谱线的现象.     

TWISTING STATICS AND DYNAMICS FOR CIRCULAR ELASTIC NANOSOLIDS BY NONLOCAL ELASTICITY THEORY

The torsional static and dynamic behaviors of circular nanosolids such as nanoshafts, nanorods and nanotubes are established based on a new nonlocal elastic stress field theory. Based on a new expression for strain energy with a nonlocal nanoscale parameter, new higher-order governing equations and the corresponding boundary conditions are first derived here via the variational principle because the classical equilibrium conditions and/or equations of motion can- not be directly applied to nonlocal nanostructures even if the stress and moment quantities are replaced by the corresponding nonlocal quantities. The static twist and torsional vibration of circular, nonlocal nanosolids are solved and discussed in detail. A comparison of the conventional and new nonlocal models is also presented for a fully fixed nanosolid, where a lower-order governing equation and reduced stiffness are found in the conventional model while the new model reports opposite solutions. Analytical solutions and numerical examples based on the new nonlocal stress theory demonstrate that nonlocal stress enhances stiffness of nanosolids, i.e. the angular displacement decreases with the increasing nonlocal nanoscale while the natural frequency increases with the increasing nonlocal nanoscale.     

Boundary derivatives of the phases of inner and outer functions and applications

We prove that boundary derivatives of the phases of inner functions exist and are positive almost everywhere, but those of outer functions, on the other hand, have zero mean on the boundary. The concepts and results have definitive applications to the definitions of instantaneous frequency and mono‐components complying with requirements in physics and contemporary study of analytic signals. Copyright © 2008 John Wiley & Sons, Ltd.     

塞曼谱线的偏振特性

根据光子角动量的量子数等于1，以及光子角动量的方向与光的偏振态的关系，详细地解释了塞曼谱线的σ偏振和π偏振是如何形成的。     

Precise potential harmonic approach to directly solving Schrodinger equations of helium-like three-body systems

A complete potential harmonic scheme is presented,including the linked coupled hyperradial ordi nary differential equations and the secular equation of eigencnergy It has been used to directly solve the Scchrodinger equations of helium-like three-body systems (nuclear charge Z=1-9),and very accurate ground state eigonenergies as well as low-lying singlet excited state ones have been obtained     

电子束参量对轫致辐射照射量角分布的影响

本文研究了电子束半径,发射度及能量等参量对闪光X射线照射量在1m处角分布的影响。求得了使中心照射量最大,束半径与发射度之间应满足的拟合关系,表明了电子束能量越高,发射度越小,那么中心照射量就越大,照射量的空间分布就越理想。对电子细束入射位置和入射方向使用了解析法和随机抽样法求出,两种方法的数值计算所得的照射量分布符合得比较好。     

角急动度与单摆的受迫振动

本文用四维相空间和四阶自洽常微分方程描写了单摆的受迫振动．     

含G对费米子动力学对称SP(10)模型的Dyson玻色子实现

将费米子动力学对称模型包含G费米子对能够构造出SP(10)或SO(12)动力学对称群.本文用GeneralizedDyson玻色子映射方法求出SP(10)对称群精确的玻色子映像,其子群SU(5)生成元的玻色子映像与sdg相互作用玻色子模型(IBM)SU(5)生成元相同,唯象sdgIBMSU(5)极限能谱公式可由费米子动力学对称模型的微观参数描述.     

各向异性内包层对双包层光纤特性影响的分析

提出了单轴各向异性材料为内包层，且其主轴沿光纤轴线（z轴）方向的双包层光纤模型，推出了矢量模特征方程，重点研究了主轴折射率比kcl对波导色散的影响，针对从矢量模特征方程求解波导色散因表达式极为复杂而无法直接求解的困难，提出了一种求解波导色散的有效方法，研究结果发现可以在不改变光波导结构参量的条件下，通过改变kcl可有效地改变光纤的波导色散，也分析了kcl、几何参量S、光学参量R对低次模的传输和截止特性的影响。研究结果为获得更为理想的色散补偿、色散平坦光纤及设计新型无源光器件提供了重要的依据。     

中子与90,91,92,94Zr反应的理论计算和分析

根据中子与天然Zr及其同位素反应的总截面,去弹截面和弹性散射角分布的实验数据,得到一组普适的光学模型势参数;应用得到的光学模型势参数,光学模型,Hauser-Feshbach理论,预平衡反应的激子模型和扭曲波玻恩近似理论,系统计算和分析了中子与^90,91,92,94Zr反应的非弹散射角分布和双微分截面,理论结果与实验很好的一致.