Effects of Double Substitution with Ge and Te on Thermoelectric Properties of a Skutterudite Compound

Studies have shown that the thermoelectric properties of CoSb₃ could be improved by the substitution of group IVB or VIB elements for Sb. However, the substitution volume is limited. To get a better picture of the substitution volume in view of thermoelectric properties, Ge and Te double-substituted skutterudite materials were prepared with the nominal composition of Co₄Sb _x Ge_5.9−0.5x Te_6.1−0.5x (x = 11, 10, 9, 8) by the traditional solid-state reaction method and spark plasma sintering, and Rietveld analysis was employed to refine the crystal structure. The results showed that the lattice parameter decreased linearly and the solubility limitations of group IVB and VIB elements were greatly alleviated by the Ge and Te codoping. Besides, the thermoelectric properties were analyzed through measurements of electrical and thermal conductivities as well as room-temperature electrical transport properties. The results showed that the substitution volume of Ge and Te could play an important role in the thermoelectric properties, and a minimum lattice thermal conductivity value of 1.56 W m⁻¹ K⁻¹ was obtained at around 673 K for Co₄Sb₈Ge_1.9Te_2.1. Co₄Sb₁₁Ge_0.4Te_0.6 achieved the best figure of merit of 0.89 at around 773 K, which was remarkably improved over that of untreated CoSb₃.     

基于单片机的智能家庭信息传输与安全防范系统

本系统采用ＭＣＳ－５１单片机控制实现家庭信息的采集与传输和安全防范监控功能,能对家庭的主要信息－每月的用电、用水和用气量自动记录并传输入各小区中心,同时,通对各类敬情监控,可杜绝家庭财产被盗和保障人身安全。本文介绍了系统结构和主要功能能主软硬件的实现。     

光纤干涉测距仪中倍增光纤长度的自标定

介绍了一种利用半导体激光器作光源 ,在光纤干涉测距中标定光纤光程差的自标定方法。它不需要借用外界仪器 ,仅利用自身的测量系统就可以精确地标定两组光纤的光程差。将标定结果引入测量系统 ,就可以实现测量系统的量程倍增 ,从而实现无长导轨的大距离、高精度测量。     

Inverse Filter of Chaos with Applications on Parameter Estimation

Linear filter may hide simple nonlinearity of chaotic dynamics, which would decrease the accuracy of parameter estimation, and reduce the effect of signal processing. Based on theoretical and experimental analysis, this paper provides a method to recover the dynamics. An example of radar data proves that the dynamics hidden in observed data can be found by inverse filter of chaos. It is also pointed out that inverse filter of chaos can be applied to mine inner regulation of some time series and estimate parameters of nonlinear models in data processing for radar. And the method is significant to clutter modeling.     

磷化铟单晶衬底的缺陷控制和高质量表面制备

分析研究了一些缺陷对InP单晶衬底的影响,包括团状结构位错的产生及其对晶格完整性的影响,坑状微缺陷、晶片抛光损伤和残留杂质的清洗腐蚀等.对这些缺陷的形成原因和抑制途径进行了分析.在此基础上获得了"开盒即用(EPI-READY)"、具有良好晶格完整性、表面无损伤的InP单晶衬底抛光片.     

超薄SiO2软击穿后I-V特性的饱和性质

利用电子速度饱和概念和比例差值方法（proportional difference operator, PDO）研究了超薄SiO2在第一次软击穿以后栅电流随着栅电压的变化所呈现的饱和性质. 实验证明了第一次软击穿以后栅电流随着栅电压变化的PDO谱峰位、峰高与电子在第一次软击穿通道中运动的饱和速度及饱和电流密度相关. 基于缺陷散射机制，得到的第一次软击穿通道的横截面积与文献报导的结果一致.     

具有n+浮空层的体电场降低LDMOS结构耐压分析

针对薄外延横向功率集成技术的发展,提出一种降低体内电场REBULF(REduced BULk Field)的新耐压技术,并设计了一例具有n+浮空层的REBULF LDMOS新结构.新耐压机理是通过嵌入在高阻衬底中的n+浮空层的等电位调制作用,提高源端体内低电场而降低漏端体内高电场使纵向电场重新分配,同时使衬底耐压提高.借助二维数值分析,验证了满足REBULF的条件为n+层的位置与衬底浓度的乘积不大于1×1012cm-2;在保证低的比导通电阻条件下,新结构较传统LDMOS结构击穿电压可提高75%以上.     

CO_2激光切雕机及其加工工艺的研究

一种可用于雕刻和切割非金属的新型ＣＯ２激光设备。介绍了这套设备各部分的结构特点、工作原理以及计算机软件的工作原理。并简述了该设备进行雕刻和切割时的工艺参数。     

激光治疗皮肤色素性及血管性病变的疗效观察

本文报告用维纳斯多波长、多功能的固体激光、治疗各种色素性及血管性病变379例。其中对黑兰色素性病变治愈率可达98％以上，对血管性病变治愈好转率可达80％以上。该治疗方法副作用少，目前是治疗色素性疾病及血管性疾病的最好方法。