安全轮胎及其在军车上的应用

概述安全轮胎的历史和发展趋势,重点介绍安全轮胎的类型、优缺点及其在军车上的应用情况.安全轮胎始于20世纪初期,我国于20世纪中期开始研制安全轮胎,安全轮胎主要有自封型安全轮胎、自体支撑(胎侧补强)型安全轮胎和加物支撑(内支撑)型安全轮胎等.目前我军发展安全轮胎应以橡胶充气轮胎为基础开发加物支撑型安全轮胎,同时应及早规划安全轮胎系列,协调制定相关技术标准.     

Developments of the electrochemical noise method (ENM) for more practical assessment of anti-corrosion coatings

The electrochemical noise method (ENM) has particular attractions because of its non-intrusive nature, quickness in gathering data and ease of interpretation. The electrode arrangement for the standard (“Bridge”) method of conducting ENM requires two separate working electrodes, e.g. two painted Q panels and a reference electrode. Although satisfactory for laboratory use, it is not so suitable for monitoring or quality control. An improved experimental configuration is the single substrate (SS) method but this still requires the metal to be connected to the measuring instrument. This is avoided in the most recent development which needs no connection to substrate (NOCS). Results will be given for immersed low VOC samples monitored using the ENM NOCS arrangement and compared with the standard (“Bridge”) method and DC resistance. Results will also be presented for work done using several different electrodes (platinum, calomel and silver/silver chloride). It is accepted that, because of the very small voltages and currents involved, ENM data can sometimes be affected by extraneous signals (although normally the results are changed by only a factor of two or less) and it may be that NOCS is more sensitive to interference of this type than the standard bridge arrangement. A simple data analysis package checking on the Gaussian nature of data enables the operator to have confidence in the R_n value. This has been applied to NOCS data. Further work is required to make ENM attractive enough to be employed as the electrochemical method of choice by users, specifiers and producers of organic anti-corrosive paints.     

Developments in separator technology for electrochemical reactors

Some of the most important electrochemical processes are performed in so-called “divided cells”. These take their name from the presence of a separator dividing the cell into an anodic and a cathodic compartment, with the purpose of improving product purity and current efficiency. One can distinguish two main classes of separators, according to the physico-chemical constitution and mode of action, ie porous diaphragms and ion-selective membranes. This review outlines the developments accompanying the progress of materials science, to meet the ever more exacting requirements of electrochemical engineering in several fields, such as chlorine-caustic production and water electrolysis.     

芳基取代香豆素合成方法的研究进展

本文综述了在香豆素母体环上具有不同取代基的3-位和4-位芳基取代化合物的合成进展。其中Perkin反应以水杨醛和芳基乙酸为原料，在有机碱和醋酸酐存在下反应，而对于有N，N-二乙氨基取代的香豆素则需要用Knoevenagal反应在催化量的有机碱存在下由N，N-二乙氨基取代的水杨醛与芳基乙腈反应制得。由于一些取代水杨醛的合成比较困难，这时可利用Pechmann反应在路易斯酸催化下由取代酚直接反应制备香豆素化合物，以上这三种制备芳基取代香豆素的方法一般收率都较高，可应用于工业化生产，另外，在Vilsmeier-Haack反应中可用Vilsmeier试剂来制备芳基香豆素化合物。该反应副产物反物很少，条件比较温和，利用钯金属等催化合成的4-芳基香豆素化合物反应中，避免了常用的Pechmann反应中使用等当量的矿物酸或路易斯酸。可减少对环境带来的污染。     

Developments in direct dyes for cellulosic materials

Single crystal data and the X-ray powder pattern are reported for CI Solvent Yellow 2 (l-phenylazo-4-NN-dimethylamine). The powder pattern has been indexed from cell dimensions given by single crystal measurements. The problems of multiple indexing have been reduced by comparing the powder data with observed single crystal intensities.     

Developments in Coloration for the Carpet Industry

Meeting of the Bradford Junior Section, held in Bradford Technical College, on 13 October 1969, Mr R. S. Stringer in the chair The improvement in wet fastness of anionic dyes, e.g. C.I. Acid Blue 25, on nylon fibres by aftertreatment with natural tannins is attributable mainly to modification of the substrate by the tannin, which lowers the rates of diffusion of the dye (a) out of the dyed fibre and (b) into undyed adjacent nylon. Ultraviolet spectroscopy of solutions of tannic acid (a polygalloylated glucose) has given indications of the alkaline oxidative degradation of the tannin believed to be responsible for the discoloration of backtanned dyeings. Tartar emetic increases the effectiveness of backtanning by formation of a less soluble complex with tannic acid which is more resistant to alkaline oxidation. Formic acid increases the rate of diffusion and the equilibrium uptake of tannic acid on nylon. The adsorption and diffusion behaviour of several related anthraquinone acid and disperse dyes on nylon is discussed and possible explanations are advanced of the low effectiveness of backtanning in preventing loss of dye by dyed nylon 6 and staining of undyed wool. No conclusive evidence has been obtained of interaction between C.I. Acid Blue 25 and tannic acid or tartar emetic in aqueous solution.     

车用甲醇燃料裂解催化剂及其研究概况

氢是一种洁净的能源，是未来最有希望的车用高能燃料。甲醇裂解是H2和CO的主要来源。重点综述了甲醇裂解催化剂体系的研究状况，并介绍了各类催化剂的催化性能以及制备工艺和操作条件对其催化活性、选择性和稳定性等的影响，对甲醇裂解催化剂体系今后的发展前景做了展望。     

Self-healing coatings for steel

The efficacy of a “self-healing” corrosion protection coating system for use on steel enclosures for outdoor equipment has been investigated using urea formaldehyde microcapsules (50–150 μm in diameter) containing several types of film forming compounds (healants) and corrosion inhibitors mixed into commercially available coatings systems. Five different types of inhibitors/film formers were tested, and three different techniques for application of the coatings with microcapsules were evaluated. Laboratory tests showed that when the coating system was damaged by abrasion, the microcapsules released the film forming and corrosion inhibiting compounds. Steel substrates coated with these self-healing systems were scribed and laboratory tested according to ASTM D 5894. Undercutting at the scribe (ASTM D 1654) was reduced by using microcapsules containing self-healing compounds. Growth of coating damage at the scribe was arrested in self-healing coatings with all microcapsule formulations compared to control samples. The performance of some microcapsules evaluated in this study was found to be dependent on the method of application.