DDS—1型多功能电子实验箱

在进行各种电子实验、研制电子产品的过程中 ,信号源及各种测量仪表是必不可少的。DDS- 1型多功能电子实验箱即可满足这方面的需要。它自备 5路电源 ,能产生多种标准的模拟信号和数字信号 ;同时可方便地用来对各种信号的幅度、频率、工作状态等进行测量和显示 ;具有宽阔的实验操作平台、手提式机箱及组装式平面结构 ,使用、维护、携带均很方便。本文介绍该实验箱的功能、原理及设计特点。     

埋地管道不开挖地面腐蚀检测技术在胜利油田纯梁采油厂的应用

综合利用管道探测、防腐保温层破损点定位、防腐保温层性能检测评价、管道阳极倾向点识别和管壁剩余厚度检测评价等技术对胜利油田纯梁采油厂的纯梁首站—史南站19.92km输油管道进行了不开挖腐蚀检测。通过检测评价,对被检管道的走向与埋深进行了精确定位,并确定了需更换、维修及重点监控与维护的具体部位,为被检管道的更换、维修及维护提供了科学依据,对保障管道安全运行具有重要意义。     

自锁式景观砌块加筋挡土结构的设计与应用

介绍砌块仿花岗岩挡土结构的特点和砌块形状,针对砌块挡土结构在我国刚开始应用,没有设计、施工规范的现状,依托可以借鉴的加筋挡土结构和浆砌块石挡土结构设计规范,提出了自锁式砌块加筋挡土结构设计中的地面荷载强度及土压力计算方法、砌块层间稳定验算方法、加筋长度和间距验算方法、挡土结构整体稳定验算方法和施工过程中需要注意的主要问题,为自锁式砌块加筋挡土结构设计人员提供了设计验算内容、验算方法和安全系数取值范围,为现场施工和监理人员提供参考,并为该类型的挡土结构推广应用提供技术支持。     

The development of MHD cold wall channels in the oil-fired condition

The durability of a cold wall MHD generator consisting of metal electrodes and alumina-coated peg insulators was experimentally examined in the oil-fired MHD condition with the additive of SO₂ corresponding to S = 0.54 wt%. The structure of the electrode wall and various anode and cathode materials were tested, with particular reference to developing long-life electrodes. It was clarified that Pt, SHOMAC (28.8 Cr−1.9 Mo) and SUS-304 as anodes and W---Cu (70 W−30 Cu) and WC---Ag (60 WC−40 Ag) alloys as cathodes were promising for durability and that the structure of an anode divided into two elements connected to each other with an SnO₂ resistor was very useful for uniformity of the anode corrosion pattern and the inter-anode voltages. It is reasonable to expect, from the test results, that the lifetime of a cold wall MHD generator in an oil-fired commercial plant will be over 4000 h, and therefore, a foundation for its commercial use has been established.     

A protein which masks galactose receptor mediated phage susceptibility in Lactococcus lactis subsp. lactis MPL56

A 28.5-kb plasmid, isolated from Lactococcus lactis subsp. lactis MPL56, causes complete inhibition of four lactococcal phages. Cell wall characteristics of wild-type strain MPL56 were compared with its 28.5 kb plasmid-cured, phage-sensitive derivative MPL56-22. After proteolytic enzyme treatments, adsorption of phages occurred at high levels, an example is 94.6–98.5% in MPL56 cells. Analysis of cell wall extracts of MPL56-22 by sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) indicated that the only difference between strains was the 55.4 kDa band in protein patterns of MPL56. Adsorption of the four phages was completely inhibited when MPL56-22 cells were subjected to SDS, Triton-X-100, HCl and NaOH treatments. Lectins that were specific for glucose/mannose and N-acetylglucosamine did not prevent adsorption of phages in cell wall extracts of MPL 56-22. However a lectin specific for galactose (MCA; Momordica charantia ) completely inhibited adsorption of these phages in cell wall extracts of MPL56-22. HPLC patterns of cell wall carbohydrates of MPL56-22 and its HCl treated preparations showed that the most prevalent difference was the galactose on untreated MPL56-22 cell wall chromatograms.     

用瑞利波检验高喷防渗墙的施工质量及地层分布特征

本文阐述了瞬态多道瑞利波探测的原理和方法，并将其应用到大堤高喷防渗墙施工质量的检验中，取得一定成效，测试结果与测压管观测结果对比，相互吻合，为类似工程的质量检验提供了一种可采用的检测手段。     

一种系统信息提示的方法及其在汇编程序设计中的实现

本文介绍了系统信息提示的一种方法，井重点讨论了用８０８８汇编语言实现的方法。它采用基本信息串表和索引表，对于使用频度较高的系统，可以大大节约系统内存，具存较好的实性用。     

住宅室内材质的合理运用

分析了住宅室内材质的功能与表现，介绍了室内材质的设计原则以及室内材质协调的基本规律，例举了住宅室内材质的合理运用，以展现出人性化的居住空间。     

串行接口LED数码管及键盘管理器件ZLG7289A的原理与应用

介绍了LED数码管及键盘管理器ZLG7289A的原理与应用。该芯片具有SPI串行接口，可同时驱动8位共阴式数码管(或64只独立LED)，还可连接多达64键的键盘矩阵，单块芯片即可完成LED显示、键盘接口等全部功能。文章给出了ZLG7289A的特点、引脚功能、指令说明和经典电路．并以单片机AT89C51为例，给出了其接口电路及相应源程序。     

Aggregate States and Energetic Disorder in Highly Ordered Nanostructures of para‐Sexiphenyl Grown by Hot Wall Epitaxy

We report on photoluminescence (PL) and thermally stimulated luminescence (TSL) in highly ordered nanostructures of para‐sexiphenyl (PSP) grown by hot wall epitaxy (HWE). A low‐energy broad band is observed in the PL spectra that can be attributed to the emission from molecular aggregates. While the intrinsic exciton emission in steady‐state PL dominates at low temperatures, the emission from aggregates increases with elevating temperature and its magnitude depends sensitively on film preparation conditions. Time‐resolved PL measurements showed that the aggregate emission decays with a life‐time of ≈ 4 ns, which is approximately an order of magnitude larger than the lifetime of singlet excitons. TSL data suggests the presence of an energetically disordered distribution of localized states for charge carriers in PSP films, which results from an intrinsic disorder in this material. A low‐temperature TSL peak with the maximum at around 30 K evidences for a weak energy disorder in PSP films, and has been interpreted in terms of a hopping model of TSL in disordered organic materials.