一维双原子链中杂质引起的局域振动模

对含杂质的一维双原子链,在链中所有原子之间近邻相互作用力常数均相等的情况下,数值求解晶格振动的运动方程组,得到不同局域振动模的振动图像和产生条件,给出了局域模关于杂质原子质量和原胞中两种晶格原子质量比分布的相图．     

热电材料研究进展

在介绍热电材料制冷工作原理,分析热电材料优值系数的基础上,介绍了300K以下热电材料的研究进展,以及热电材料制冷特点、现状和应用前景．     

Small-angle X-ray analysis of the effect of grain size on the thermal damage of octahydro-1, 3, 5, 7-tetranitro-1, 3, 5, 7 tetrazocine-based plastic-bounded expolsives

The microstructure evolution of plastic-bonded explosives(PBXs) after thermal stimulus plays a key role in PBX performance. In this paper, the nanoscale pores of thermal-treated octahydro-1,3,5,7-tetranitro-1,3,5,7 tetrazocine(HMX)-based PBXs with different HMX particle sizes [approximately 40(FHP) and 100 μm(LHP)] were measured using smallangle X-ray scattering(SAXS). No obvious pore variations were found in the LHP samples heated at 160℃ for 6 h,whereas the amount of pores of FHP decreased when subjected to 160℃ for 6 h. At 180℃, the average pore radii of FHP and LHP decreased from approximately 45 nm to 25 nm, and the total pore volume increased distinctively because of phase transformation. The LHP sample reached a high level of pore content after being held at 180℃ for 1 h, whereas FHP required 3 h. Both FHP and LHP had relatively high pore volumes when subjected to 200℃ for 1 and 3 h.     

三明治结构量子阱的维数

讨论了无限深和有限深量子阱电子系统的维数.在无限深量子阱中,随着阱宽由大减小到零,量子阱的维数由3单调减小到2;有限深量子阱中,在阱宽较大或阱宽趋于零时,量子阱电子系统的维数都趋近于3,随着阱宽的减小,量子阱的维数呈现出先减小后增大的情况,存在一个维数极小值.     

Different Kinds of Discrete Breathers in Three Types of One-Dimensional Models

The dynamics of different kinds of discrete breathers in three types of one-dimensionai monatomic chains with on-site and inter-site potentiais are investigated. The existence and evolution of symmetric breather, antisymmetric breather, and multibreather in one-dimensionai models are proved by using rotating wave approximation, local anharmonic approximation, and the numerical method. The linear stability of these breathers is investigated by using Lyapunov stable anaiysis. The localization and stability of breathers in three types of models correlate closely to the system nonlinear parameter β.     

肠易激综合征治疗药匹维溴铵的合成

肠易激综合征(irritable bowel syndrome,IBS)是与肠道动力学和内脏感觉异常有关的功能性疾病,是指一组包括排便习惯改变(腹泻或便秘)、粪便性状异常(稀便、黏液便或硬结便)、腹痛、腹胀等临床表现的症候群,持续存在或间歇发作,但无器质性疾病的证据.     

晶格振动简正坐标的具体表述及其讨论

在明确简正坐标定义的基础上，分析了一维单原子链简正坐标的具体表述，并给出了一种新的表达式。     

Existences and stabilities of bright and dark breathers in a general one-dimensional discrete monatomic Chain

A general one-dimensional discrete monatomic model is investigated by using the multiple-method. It is proven that the discrete bright breathers (DBBs) and discrete dark breathers (DDBs) exist in this model at the anti-continuous limit, and then the concrete models of the DBBs and DDBs are also presented by the multiple-scale approach (MSA) and the quasi-discreteness approach (QDA). When the results are applied to some particular models, the same conclusions as those presented in corresponding references are achieved. In addition, we use the method of the linearization analysis to investigate this system without the high order terms of $\varepsilon$. It is found that the DBBs and DDBs are linearly stable only when coupling parameter $\chi$ is small, of which the limited value is obtained by using an analytical method.     

光频支格波对晶格热容的贡献

讨论晶格的光频支格波对晶格热容的贡献，得到了这部分的热容的表达式。在低温极限情况下,光频支格波对晶格热容的贡献很小，可以忽略，只有频率较低的声频支格波对晶格热容有重要贡献；在高温情况下，复式 和中光频支格波对晶格热容有重要贡献，高温情况下的结果与杜隆－珀蒂定律给出的经典数值一致，该定律在高温时与实际实验符合得很好。     

异常霍尔效应和自旋霍尔效应

异常霍尔效应和自旋霍尔效应是在常规霍尔效应的基础上引发出的2种新现象.本文介绍了这2种现象及其原理和潜在的应用.