TATB钝感炸药的小角X射线散射实验

在北京同步辐射装置上应用同步辐射X射线小角散射技术研究TATB样品微孔状况，分析了微孔结构参数的变化。采用不同制备工艺(机械研磨、化学合成、气流细化、全结晶、粉碎)和不同存放时间的TATB粉末样品共计7份。     

一般组合弹性结构的数学模型

研究由任意多个体、板、梁构成的一般组合弹性结构静态问题. 通过最小势能原理和虚功原理建立问题在向量表示下的数学模型. 在获得了一般组合弹性结构上的广义Korn不等式后, 利用Lax-Milgram引理证明了模型的唯一可解性. 在对解做合理的正则性假设的条件下, 由相应变分形式导出向量表示下的所有平衡方程, 并得到了一个对该问题进行有限元分析时有重要作用的恒等式.     

Effects of External Electric Field on Ferroelectric Superlattice with Two Alternating Layers

The effects of the external electric field on the ferroelectric superlattice with two alternating layers have been studied using the transverse Ising model based on the effective-field theory with the differential technique. The hysteresis loops and susceptibility of the system have been given. The stronger the external electric field, the smaller the susceptibility, reflecting that the polarization is weaker.     

Recombination Efficiency in Double-Layer Organic Light-Emitting Devices

We analyse the influence of properties of organic/organic interface (OOI) on the characteristics of recombination efficiency of organic double-layer light-emitting diodes. Based on the disordered hopping theory model, spatial and energetic disorder of hopping states are also discussed for the case of space charge limited currents in hole transmitting layers but injection-limited currents in electron transporting layers. The results show that the recombination efficiency increases firstly and then decreases for different OOI parameters, and there is a maximum value changed with different spatial disorder parameters and energetic disorder scale. Different spatial disorder parameters make carrier mobilities change greatly, and the energetic disorder scale causes various localized state densities. Our calculated results are qualitatively in agreement with the experimental data.     

德摩根一致代数的度量化

我们给出了德摩根一致代数可伪度量化的一个充分必要条件。     

高能、超短脉冲、可调谐激光器用掺镱氟磷酸盐玻璃研究进展

Yb^3 与其它稀土离子相比有最简单的能级结构，这使它具有一些独特的性质，如避免激发态吸收，消除上转换和浓度猝灭等，因此它是高能输出激光器介质的理想掺杂离子。氟磷玻璃综合了氟化物玻璃和磷酸盐玻璃的优点，可降低磷酸盐的声子能量，改善其易吸湿性；提高氟化物玻璃的物理化学性能等，这使它成为稀土掺杂可调谐光纤激光器的很好的掺杂介质。众多研究表明，Yb^3 掺杂氟磷玻璃是一种很有前途的激光工作物质。本文总结了Yb^3 掺杂氟磷玻璃的特点，性质，结构及存在的问题。     

利用全息扫描技术实现条码识别

根据条码识别装置的特点，利用全息扫描技术设计条形码扫描器及相应的辅助部件，从而使学生对全息照相及扫描技术有进一步的理解，掌握物理实验设计的一般要求。     

Electron Holography of Barrier Structures in Co／ZrAlOx／Co Magnetic Tunnel Junctions

We investigate the potential profiles and elemental distribution of barriers in Co/ZrAlOx/Co magnetic tunnel junctions (MTJs) using electron holography (EH) and scanning transmission electron microscopy. The MTJ barriers are introduced by oxidizing a bilayer consisting with a uniform 0.45-nm Al layer and a wedge-shaped Zr layer (0-2 nm). From the scanning transmission electron microscopy, AlOx and ZrOx layers are mixed together, indicating that compact AlOx layer cannot be formed in such a bilayer structure of barriers. The Eli results reveal that there are no sharp interfaces between the barrier and magnetic electrodes, which may be responsible for a smaller tunnelling magnetoresistance compared with the MTJs of Co/AlOx/Co.     

Theoretical Analysis of Characteristics of GaxInl—x NyAsl—y／GaAs Quantum Well Lasers with Different Intermediate Layers

Based on the band anticrossing model, the effects of the strain-compensated layer and the strain-mediated layero n the band structure, gain and differential gain of GalnNAs/GaAs quantum well lasers have been investigated. The results show that the GaNAs barrier has a disadvantage in increasing the density of states in the conduction band. Meanwhile, the multilayer quantum wells need higher transparency carrier density than the GalnNAs/GaAs single quantum well with the same wavelength. However, they help to suppress the degradation of the differential gain. The calculation also shows that from the viewpoint of band structure, the strain-compensated structure and the strain-mediated structure have similar features.