椭圆截面圆环和扭圆环的转动惯量

首先建立了椭圆截面的圆环和扭圆环的数学模型,然后根据定义计算绕3个坐标轴的轴转动惯量和惯量积,其间充分利用截面图形的对称性对计算过程简化,得到一些有益的结论和结果.     

Design of a multiband terahertz perfect absorber

A thin-flexible multiband terahertz metamaterial absorber(MA) has been investigated. Each unit cell of the MA consists of a simple metal structure, which includes the top metal resonator ring and the bottom metallic ground plane,separated by a thin-flexible dielectric spacer. Finite-difference time domain simulation indicates that this MA can achieve over 99% absorption at frequencies of 1.50 THz, 3.33 THz, and 5.40 THz by properly assembling the sandwiched structure.However, because of its asymmetric structure, the MA is polarization-sensitive and can tune the absorptivity of the second absorption peak by changing the incident polarization angle. The effect of the error of the structural parameters on the absorption efficiency is also carefully analyzed in detail to guide the fabrication. Moreover, the proposed MA exhibits high refractive-index sensing sensitivity, which has potential applications in multi-wavelength sensing in the terahertz region.     

球状物体作微形变时弹性势能的研究

研究一个弹性球在保持体积不变的前提下,形变为长旋转椭球时的弹性势能.首先通过最小势能原理和物理条件确定位移函数,然后根据弹性势能密度-应变-位移三者之间的关系,通过积分计算得到弹性势能,并且进行了有益的讨论.     

Improvement of memory characteristics by employing a charge trapping layer with combining bent and flat energy bands

Designed ZrxSi1-xO2 films with combining bent and flat energy bands are employed as a charge trapping layer for memory capacitors.Compared to a single bent energy band,the bandgap structure with combining bent and flat energy bands exhibits larger memory window,faster program/erase speed,lower charge loss even at 200℃ for 104s,and wider temperature insensitive regions.The tunneling thickness together with electron recaptured efficiency in the trapping layer,and the balance of two competing electron loss mechanisms in the bent and flat energy band regions collectively contribute to the improved memory characteristics.Therefore,the proposed ZrxSi1-xO2 with combining bent and flat energy bands should be a promising candidate for future nonvolatile memory applications,taking into consideration of the trade-off between the operation speed and retention characteristics.     

太空液桥实验的理论研究——由太空课堂引起的又一教学案例

本文针对天宫课堂第二课中的液桥实验进行理论研究.基于液桥的对称性和体积不变性，根据最小势能原理，我们获得液桥形状的几何方程，据此探讨液桥形状随其长度的变化规律和最大长度.发现一个描述液桥形状的特征参数R,并揭示该参数与液桥内部压强的关系.