退火对PMN—PT系陶瓷电学性能的影响

研究了退火对（１－ｘ）ＰＭＮ－ｘＰＴ（ｘ＝０－０．３４）陶瓷介电和压电性能的影响。分析了机理。结果表明，在ＰＴ含量较低时，退火使介电常数稍有提高；ＰＴ含量较高，接近准同型相界时，退火使介电常数有较大提高，尤其在居里温度附近，介电常数有显著提高。     

Domain behavior in lead zirconate titanate (PZT) thin film capacitors

Abstract

Domain behavior based on surface energy and volumetric free energy was discussed in relation to imprint. Surface enery and volumetric free energy result in net free energy, which determines the critical size for domain growth. If a domain size is greater than the critical size, they will grow spontaneously under a constant electric field or even under zero electric field. Sometimes, they can grow to the extent that they dominate reverse domains. This phenomenon appears to be polarization reversal under zero voltage bias. Spontaneous domain growth either under zero electric field or a constant electric field was demonstratred. This phenomenon can be partly a source of asymmetric imprint mechanism.     

PT断线闭锁保护误动的分析和处理

对变压器PT断线闭锁继电器误动进行分析 ,发现其在原理上存在缺陷 ,提出解决措施。     

核电管道承插焊口的射线透照工艺

承插焊接的连接形式主要用于小口径阀和管道、管件和管道焊接，其结构形式为管道的插入角接型式，接头属于角接接头，由于其厚度的不同和其结构的特殊性，和厚度差变化范围较大，此种接头的内部检验给射线检测带来了一定难度泰文针对承插焊口的拍片过程及其特点，提出了采用自设自装的一种可提高插套拍片效率、准确度的焦距堆直器，在检测过程中，采用背屏及滤光板进行散射线控制，结合透照厚度的计算确定检测工艺参数的透照检测工艺参数，包括曝光时间，曝光，焦距以及胶片尺寸的大小。此种工艺的提出，可适应核电各系统的插套的检测，检测技术及工艺的应用在其他工程建设方面也有较强的借鉴推动作用。     

GIS中电压互感器中性点接地击穿间隙频繁击穿的原因分析及处理方法

针对GIS中电压互感器中性点接地击穿同隙频繁击穿的现象,分析了击穿原因,指出击穿系由隔离开关操作引起的快速暂态过电压通过耦合电容的传遵而造成,并提出了经过实践检验的解决方法。     

PT2262/PT2272编解码IC在视频切换矩阵中的应用

提出了一种用PT2262/PT2272编解码IC制作的16×16视频切换矩阵的设计方案 ,给出了具体的电路图 ,同时在对其原理进行分析的基础上 ,指出了用该方案派生其它规格视频切换矩阵的基本思路。     

70t超高功率电炉节能降耗的技术措施

简要介绍了淮钢70t超高功率电炉应用铁水热装、PTIJetBOx集束射氧喷箱系统、二次燃烧和低纯度氧气炼钢等技术的情况。     

色拉油自动化生产线监控系统研发与应用

色拉油自动化生产线监控系统，借鉴引进世界名的瑞典Alfa Laval自动化生产线运行所显示的功能、性能及其各项技术指标，结合国情别具一格的创新采用高新技术，自行设计研发独具特色的拥有自主知识产权的国产化、智能化、网络化监控系统。具有前瞻性、先进性、新颖性、通用性，且性能可靠、运行稳定、操作灵活、维修方便、性价此优的特点。已在省内外得到推广与应用，并取得令人满意的效果。     

Semiconductor-to-metallic phase transition of VO<Subscript>2</Subscript> by laser excitation

VO₂ thin films deposited on MgO and fused silica glass substrates were prepared by the pulsed laser deposition (PLD) technique, which shows phase transition (PT) from the monoclinic semiconductor phase to a metallic tetragonal rutile structure at temperatures over 68°C. The observed PT is reversible, showing a typical hysteresis. The PT can also be induced through optical pumping by laser excitation. In this case, it was found that the optically induced PT is ultrafast and passive, but not thermally initiated. In order to understand the PT mechanism, a study of transient holography using degenerate-four-wavemixing (DFWM) measurement was conducted. A Nd:YAG pulsed laser with pulse duration of 30 psec operating at 532 nm was employed as the coherent light source. This showed that the observed transient holography in VO₂ thin film is associated with the excited state dynamical process, which essentially causes the structural change, or so-called optically induced PT. The observed extremely large polarizability is believed to relate to the large offset in the potential well minimum between the ground state and excited state. Through an unidentified intermediate state, the transient lattice distortion triggered the structural change.     

小接地系统4PT方式的二次电压分析与建模

中性点不接地系统中4PT接线方式是消除铁磁谐振的一项有效措施。系统分析了4PT方式下正常和故障态时的二次电压特征。之后针对现场经常出现的中性点PT极性反接的问题,总结出随着相PT和中性点PT阻抗比值的变化,二次测量电压的分布规律。最后,建立了基于PSCAD/EMTDC的4PT仿真模型,进行多种工况下的仿真;并结合现场运行实例,验证了理论计算的正确性。的工作给变电所运行和检修人员提供了4PT方式的运行维护提供了参考经验。