混凝土预制板防渗渠道技术探讨

介绍了混凝土预制板防渗渠道施工过程及施工方法,并提出施工中应注意的问题。     

GML在IP网管中实现分域分级管理的方法

提出将网络管理与地理信息系统GIS结合起来，以空间信息管理的观点，利用GML实现IP网管的分域分级管理，并结合天盟网络公司的TBE(天盟宽带引擎)网管系统，讨论了GML实现分域分级管理的关键技术。     

Preparation of nanosized titania powder via the controlled hydrolysis of titanium alkoxide

By controlling the hydrolysis of titanium butoxide, followed with or without an ethanol washing process, the preparation of nanoscale titania powder was studied in detail. The characteristics of different powders produced by the direct precipitation (without an ethanol wash) and ethanol wash processes were studied by X-ray diffraction, transmission electron microscopy, BET, thermogravimetry and differential thermal analysis techniques. By comparison, it was found that both the direct precipitation and ethanol wash methods can obtain slightly agglomerated nanoscale titania powders of less than 15 nm, but the ethanol wash can further reduce the agglomeration. The particle sizes of titania powders can be modified while still retaining the anatase structure.     

Effect of processing history on the properties of Ag-based tapes

The Bi-system tapes and coils were prepared by the powder-in-tube method. The effect of processing and heat treatment on the properties of the tapes and coils was studied. It is found that the shearing stress produced by the rolling process may destroy the 2223 phase, and the destroyed 2223 phase cannot be recovered by heat treatment, whereas the pressing stress produced by the uniaxial pressing process only makes the 2223 phase grains break, and the broken 2223 phase can be closed by the heat treatment. TheJ _c values of the rolling samples, pressing sample, and the coil with a diameter of 35 mm are over 1.3×10⁴, 2.5×10⁴, and 4×10³ A/cm² (77 K, 0 T), respectively.     

造纸机集散控制系统

本文介绍了造纸机集散控制系统．讨论了其硬件的组成和软件结构．研究了ＤＤＳ过程级控制器的功能及对造纸机各分部速度的优化控制．系统投人运行后，取得较好的经济效益．     

一种制备插层和无定形高岭土的新方法

利用甲醇钠强烈的夺氢作用 ,介绍了一种制备插层和无定形高岭土的方法。利用XRD为主要检测手段研究了甲醇钠的质量分数、反应温度等因素对反应的影响。结果表明 :在反应温度较低、质量分数较低的甲醇钠溶液中 ,高岭土容易被插层而膨胀 ,反之高岭土的层状结构被破坏而无定形化。红外光谱分析进一步证明了插层和无定形高岭土结构的变化     

单片机在监控同步电动机运行功率因数中的应用

介绍如何利用单片机自动控制同步电动机运行时的功率因数。