热分解法制备钛酸铅镧薄膜及其电性能研究

本文研究了用金属有机物热发解法制备ＰＬＴ８薄膜的工艺过程和基片对薄膜结构的影响，并且给出了铁电性能的测量结果。     

用金属有机化合物制备铁电薄膜：工艺及进展

本文概述了以金属有机化合物为原料制备铁电薄膜的工艺过程、工艺特点及最新研究进展，着重介绍了金属有机物化学气相溶积（ＭＯＣＶＤ），金属有机物热分解（ＭＯＤ）以及溶胶－凝胶（Ｓｏｌ－Ｇｅｌ）三种制备技术在铁电薄膜制备领域中的应用。     

Substrate effect on the temperature coefficient of resistance of La0.7Ca0.3MnO3 thin films prepared by metal organic deposition

Epitaxial La_0.7Ca_0.3MnO₃ (LCMO) thin films were successfully prepared by the metal-organic deposition process on various (001) single-crystal substrates: MgO, LaAlO₃ (LAO), SrTiO₃ (STO), and (LaAlO₃)_0.3-(SrAlTaO₆)_0.7 (LSAT). The crystallinity and the epitaxial growth of the LCMO films were characterized by X-ray diffraction (θ − 2θ scans and pole-figure analysis). The temperature dependence of the resistance of the LCMO/LSAT, LCMO/STO and LCMO/LAO films exhibit typical characteristics with a transition from the paramagnetic-insulator state to the ferromagnetic-metallic state at a temperature peak (T _p ) ranging from 258 to 270 K. However, the LCMO/MgO films exhibited a semiconducting behavior without any transition. Based on the R(T) measurement, we calculated the temperature coefficient of resistance (TCR) for a bolometric application and we obtained 22%/K, 10.2%/K and 27.5%/K for the film grown on the LSAT, STO and LAO substrates, respectively. This difference in the TCR properties is related to the strain induced by the lattice mismatch between LCMO and the different substrates.     

基于神经网络的全自动模式识别跟踪系统

建立了一个基于神经网络的全自动模式识别跟踪系统。通过MOD算法提取出各个运动目标的特征向量后，利用神经网络对各个目标自动进行模式分类。文中同时给出了在复杂背景下多个运动目标自动跟踪与识别的实验结果。     

Stress singularity analysis in the restorations of premolar class ii cavities

Abstract

This paper presents the singular stress analysis near the apex of a structure formed during dental restoration of a premolar class II cavity. Based on the elasticity theory, the stresses may go to infinity at the junctions of different materials (e.g. dentine, enamel, restoration materials). Tensions will cause material separation and then material fracture. In order to reduce the failure probability, the degree of stress concentration has to be reduced. The stress singularity order and the stress intensity factor are two parameters, which are often used in fracture analysis. The objective of this paper is to find conditions such that non‐singular stress fields are possible. Three critical positions in the restoration structure are discussed.

They are the tips of interface between (1) enamel and restoration; (2) dentine and restoration; and (3) enamel, dentine and restoration. In the last two cases, the restoration may be bonded or debonded to enamel or dentine. After employing Kolosov‐Muskhelishvili complex functions together with the eigenfunction expansion method, the singularity orders are computed theoretically. Weak stress singularity conditions can be sought by properly selecting cutting angles or restoration materials.     

金属有机物热分解法制备锆钛酸铅薄膜研究

采用金属有机物热分解（ＭＯＤ）法，通过对原料的提纯和合成工艺的优化，消除原料中的微量杂质，控制环境温度，从而获得了透明、稳定的锆钦酸铅先体溶液．锆铁酸铅先体溶液经过多次成膜，在Ｐｔ／ＳｉＯ２／Ｓｉ基片上制备出厚度为０．６ｕｍ，均匀、无裂纹、无针孔的薄膜．经５５０℃保温处理后，得到假立方晶系的钙钦矿结构的薄膜．借助扫描电镜形貌分析表明，其晶粒大小约为２～３μｍ．     

肉豆蔻酸酯的合成

肉豆蔻酸酯是一种国外流行的新型化妆品基质材料。本研究确定了ＭＯＤ合成路线，并探讨了影响产率诸因素。     

CPR1000非能动应急给水系统瞬态特性分析

利用RELAP5/MOD3.4程序对CPR1000压水堆在全厂断电事故下一回路主要参数的瞬态热工水力特性进行分析，验证CPR1000非能动应急给水系统(PEFWS)对事故的缓解能力。计算结果表明，CPR1000在发生全厂断电事故后，PEFWS完全可及时向蒸汽发生器补水，同时导出堆芯余热，保证反应堆处于安全状态，从而验证CPR1000PEFWS的设计成功。     

基于排队论的车站售票系统优化与改善

通过对石家庄站西广场的售票厅在春运时期的运行状况进行调查,发现其售票服务效率不高,影响旅客的满意度.针对上述问题,提出一种排队论和工业工程相结合的改善方案.该方案结合系统成本、服务效率和旅客需求等因素,利用排队理论分析车站在春运期间的负荷状况,运用工业工程中的模特法对问题实施优化改善,最后借助WinQSB软件对比得到车站在春运期间不同客流量下的合适的服务窗口需求量,并进行了敏感性分析.研究表明,工业工程的应用可以很好地提高售票服务效率、旅客满意度和服务质量,有助于合理规划现有资源,降低车站的运营成本,增强铁路部门的综合实力.     

AP1000多根蒸汽发生器传热管破裂分析

利用RELAP5/MOD3程序对AP1000多根蒸汽发生器传热管破裂事故进行了分析。基于最佳估算方法,分析了1~5根蒸汽发生器传热管破裂的工况。分析结果表明:在大气释放阀可用的情况下,主蒸汽安全阀(MSSV)始终保持关闭状态,从而不会旁通安全壳。每个工况的堆芯补水箱水位均未出现下降,不会产生自动卸压信号。即使假设MSSV卡开,堆芯也从未出现裸露,仍保持可冷却状态。