多用电表欧姆挡工作原理的理解和分析

论述了多用电表欧姆挡的工作原理.     

铁电钨青铜型晶体SBN和KNSBN的Raman谱研究

测得了Sr_1-xBa_xNb₂O₆(SBN)和(K_1-yNa_y)_z(Sr_1-xBa_x)_l-zNb₂O₆(KNSBN)晶体的Raman谱,并用群论和晶格动力学观点进行了讨论.为其掺杂改性提供了科学依据. 关键词：     

TI基高温超导单晶的生长与研究 *

在计算机控制的封闭式单晶生长炉内,采用自助熔剂法生长出最大尺寸2.0mm×2.0mm×O.3mm,典型尺寸1.0mm×1.0mm×O.1mm的TI-2223,TI-2212单晶,T_c分别达到119 K和110 K.TI的含量对晶体生长的大小、相的形成及T_c均有重要影响.TI-2212单晶的交流磁化率的虚部峰值温度 T_p和外场 H_D 的关系为(1-T_p/T_c)∝H_D^0.71(H_D//C轴)TI-2223单晶可见光区的光反射谱存在强烈的各向异性.     

Preparation and Annealing—Induced Structural Transition of Self—Organized Nanostripes on the Electropolished Aluminium Surface

Self-organized nanostripe patterns with a wavgelength of 100 nm and an amplitude of 4-5 nm were formed on the surface of high-purity aluminium by electropolishing.The thermal stability of the nanostripe patterns was investigated experimentally by using a needle-sensor atomic force microscope in an ultra-high vacuum after annealing the sample in a high vacuum.We found that the originally highly ordered nanostripe structures transformed into many domains separated by various boundaries,and different nanostripe patterns formed,the belt-like boundaries especially formed “cross” patterns on the surface.We also found that the vacuum annealing had the tendency to efface the nanostripe structures.     

微型液晶彩电的选用

微型液晶彩电的选用胡连义这两年市场上出现了几种大小和随身听差不多的微型液晶彩电。由于它图像逼真、色彩鲜艳和携带方便，受到了消费者的青睐。其实，液晶已被人类发现１００多年，它是一种具有光电效应和液体流动性的化学物质。人们最初用它做数字手表的显示屏、计算...     

Phase Diagrams and Tricritical Behaviour of the Spin-2 Ising Model in a Longitudinal Random Field

Within the framework of the effective-field theory with correlations,we study the ferromagnetic spin-2 randomfield Ising model (RFIM) in the presence of a crystal field on honeycomb (z=3),square(z=4) and simple cubic(z=6) lattices.The effects of the crystal field and the longitudinal random field on the phase diagrams are investigated.Some characteristic features of the phase diagrams,such as the tricritical phenomena,reentrant phenomena and existence of two tricritical points,are found.     

RS—232与RS—485接口转换器的设计

文章针对普通计算机的ＲＳ２３２串行接口与带有ＲＳ４８５串行接口的智能仪表、监控系统的通信，提出了ＲＳ２３２与ＲＳ４８５接口转换器的设计方案，具有一定的实用价值。     

Hubbard-Hirsch模型中的电子相关效应

基于同一格点的电子相关，把局域方法用于Ｈｕｂｂａｒｄ－Ｈｉｒｓｃｈ模型铁磁相。在二阶计算中使用Ｒ＝０，ａ近似，仔细研究了电子相关效应对基态相图的影响．由于计及了密度矩阵非对角元，其影响与Ｒ＝０近似相比变弱。     

一步彩虹全息术

提出利用透镜成象与孔径共轭技术制作大面积彩虹全息图的一步记录技术,进行了理论分析并给出了实验结果。