射频板条CO_2激光器并联谐振技术的研究

本文利用周期性网络模型计算了射频板条CO2激光器电极的纵向电压分布．探讨了并联谐振技术在板条器件中获得成功运用的原因．提出了利用并联谐振技术进一步提高电压分布均匀性的两个途径．     

一种新颖的表面等离子谐振效应光波导水质传感技术

光学表面等离子谐振（ＳＰＲ）效应是一种很有效的水质检测技术，经过详细的理论推导，同了ＳＰＲ反射光强的普遍适用公式。在纯水与受污染水两种情况下，根据一些已知参数计算出结果。由计算结果数据一出的曲线比较表明，ＳＰＲ效应在两种情况下有明显差别，这也正是ＳＰＲ效应用于水质检测的理论根据。     

DIRECT RESONANCE OF TURBULENT BOUNDARY LAVER OVER COMPLIANT WALLS

１．　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍａｉｎｇｏａｌｏｆｔｈｉｓｐａｐｅｒｉｓｔｏｅｘｐｌｏｒｅｔｈｅｐｏｓｓｉｂｉｌｉｔｙｔｏｌｅａｒｎｍｏｒｅａｂｏｕｔｔｈｅｍｅｃｈａｎｉｓｍｏｆｔｕｒｂｕｌｅｎｔｂｏｕｎｄａｒｙｌａｙｅｒｆｌｏｗｉｎｔｅｒａｃｔｉｏｎｓａｎｄｉｔｓｅｆｆｅｃｔｓｏｎｃｏｍｐｌｉａｎｔｗａｌｌｐｅｒｆｏｒｍａｎｃｅ．Ｔｈｅｒｅａｒｅｃｅｒｔａｉｎｐｒｅｒｅｑｕｉｓｉｔｅｃｏｎｄｉｔｉｏｎｓｔｏｆｕｒｔｈｅｒｔｈｅｓｔｕｄｙｏｎｔｈｅｍｅｃｈａｎｉｓｍ，ｉ．ｅ．ｔｈｅｃｏ…     

用核磁共振测井确定渗透率的原理和方法分析

对常规测井和核磁共振测井的渗透率公式进行了比较 ,发现各渗透率公式存在相互联系。几种核磁共振测井渗透率公式的计算结果和实验室渗透率的对比表明核磁共振参数和渗透率有很好的相关性 ;改进的渗透率公式可以准确地求取岩心和地层的渗透率。     

Cif2000平台下的核磁共振测井解谱方法研究

介绍了在Cif2000多井解释平台下的核磁共振解谱方法与编程实现。解谱采用加入平滑因子后在特征矩阵的奇异值分解中截去小的非零奇异值的方法，可以在低信噪比时得到稳定的弛豫谱，在油田实际应用中证明了该方法的有效性。根据该方法在Cif2000平台上编制了完整的解谱处理程序，可以直接用于油田的生产实际。     

Influence of accelerated ageing on methacrylate‐based denture resins heterogeneity as viewed by ESR‐spin‐probe method

The electron‐spin‐resonance (ESR) spin‐probe method, was used to study the heterogeneity of denture resins based on poly(methyl methacrylate). Results for three resins processed by microwave energy, conventional curing and cold curing (depending on the curing procedure and exposed to ageing in various environmental conditions) were compared. All three cured resins were stored over the same time (1200 h) in distilled water at ambient temperature and in artificial saliva at 348 K. The temperature‐dependent ESR spectra of a spin probe dispersed in the denture resins are analyzed in terms of line‐shapes and line‐widths. The appearance of two spectral components was taken as an indication of resin heterogeneity. The results reveal that the cold‐cured resin has a lower local density in comparison with microwave and conventionally cured resin. The amount of residual monomer also contributes to the local motion of polymer segments. The change of denture resins exposed to ageing is influenced both by the structure of the original resin and the ageing conditions. Restricted motion of a spin probe incorporated into the acrylic resins exposed to accelerated ageing suggests additional crosslinking of polymer chains. The differences are observed for all the investigated resins, but the highest change is observed with the cold‐cured resin. The ESR results are accompanied by T_g and T_m measurements. Copyright © 2005 Society of Chemical Industry     

天津独流减河工程监控系统现地通信单元设计

提出一种配电网电容电流测量的新方法，在零序电压互感器的开口三角侧串联一个可调电感，通过注入一个变频恒流信号寻找配电网的谐振频率，改变可调电感的数值后寻找另一谐振频率，联立2个谐振方程求解电容电流，该方法消除了电压互感器漏抗对测量的影响。开发了配电网电容电流测量仪，经模拟试验和现场测试表明，该方法具有安全、快捷、准确等特点，适用于中性点不接地或经随调式消弧线圈接地配电网。     

铁路桥梁横向振动模拟及适应快速行车结构型式的研究

针对铁路提速后出现的上承式简支钢板梁桥跨中横向振幅过大的问题,以羊楼司桥(L=32m单跨上承式简支钢板梁桥)为例进行实桥检测和数值模拟,建立车辆、线路、桥梁三者的联合模型,考虑轮轨接触力,应用MSC/DYTRAN大型结构分析程序进行车线桥动力相互作用的仿真分析。研究揭示我国用量最多的C62型货车以70∽80km/h的速度空载通过时,该跨度的钢板梁桥发生横向谐振的机理。此外,用该方法对32m跨长的组合梁结构进行桥梁动力特性及列车走行性分析,表明该结构满足提速货车和高速电动旅客列车走行的要求。研究结果对我国高速铁路桥梁建设和既有桥梁的改造具有积极意义。     

行波管放大器相位噪声的分析及其抑制

主要分析规则调相信号对行波管放大器频谱纯度的影响,并且根据行波管放大器相位噪声产生的过程和原因,提出两种抑制相位噪声的方法.     

p-Si薄膜生长的ECR-CVD等离子体系统的结构设计

提出了一种生长p-Si薄膜的ECR-PECVD等离子体系统。系统采用永磁铁和线圈相结合，改善反应室磁场的均匀性；微波窗口设计成多层结构．避免窗口污染；衬底托架移动和旋转利于改善生长膜的均匀性。