摘要:

AbstractA brief description of the electron‐transfer processes involved in the corrosion of metals is given. The relationship between the stable species formed in corrosion reactions, the pH of the aqueous solution involved, and potential of the metal, is referred to and the potentiostatic and galvanostatic methods of assessing electron‐transfer are contrasted.The development of various forms of potentiostat and the scope of the instruments are discussed, and examples given of their fields of use. The experimental techniques adopted to obtain current‐potential curves and to assess the rate of cathodic and anodic reactions are illustrated by reference to appropriate diagrams.A short section deals with the use of current/time transients for obtaining kinetic data especially for film growth and formation of

ISSN:0021-8871    

DOI:10.1002/jctb.5010130201

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractSolutions of sodium cyanide and solutions containing the complex cyanides of copper, cadmium and zinc have been electrolysed with anodes of graphite or platinised titanium at temperatures in the range 50–90°, and at anode current densities of 0–88 A/ft.2Cyanide was destroyed at rates of 14.0–15.9 g. of HCN/Faraday (0.5–0.6 mole/Faraday), 1 kWh electricity destroying 146–201 g. of HCN. The rate of destruction was directly proportional to current passed and increased with increase in temperature. Increase in the electrolyte pH decreased the rate of destruction of cyanide. The chief reaction products were ammonium carbonate, and cyanate ions and urea. Stainless steel (EN 58A) was not an efficient anode material. A method for the continuous destruction of solid cyanide waste, on a laboratory scale, by electrolytic oxidation is described. The only products of the process are gaseous (ammonia, carbon dioxide and hydrogen) and solid (sodium carbonate containing 0.05% cyanide and 0.26% sodium oxalate), 1 kWh of electricity destroying 111–1

ISSN:0021-8871    

DOI:10.1002/jctb.5010130202

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractMethods are described for estimating the total content of natural (unvulcanised) rubber in a rubber‐bitumen and the effective rubber content; the latter is defined as the concentration of a standard rubber which would give a specific viscosity equivalent to that of the rubber in the test sample. The total rubber content is calculated from the iodine value of a solution, in carbon tetrachloride, of the acetone‐insoluble fraction of the rubber‐bitumen. The effective rubber content is determined by a measurement of the specific viscosity of a benzene solution of the acetone‐insoluble fraction of the rubber‐bitumen. The effective rubber content has been shown to be related to the elastic recovery of the binder.Both analytical techniques have been used to follow the effect of heating on rubber‐bitumens and recommendations are given on the conditions of temperature and duration of heating in the preparation of rubberised binders f

ISSN:0021-8871    

DOI:10.1002/jctb.5010130203

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractAn ultra‐violet spectroscopic method is described for the determination of the antioxidant Topanol OC (2,6‐di‐t‐butyl‐4‐methylphenol) in stabilised Lanolin. The determination is based on the corrected absorbance at 283.5 mμ and the interfering absorptions arising from the Lanolin are removed by compensation with a standard Lano

ISSN:0021-8871    

DOI:10.1002/jctb.5010130204

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractThe condensation of acetone at room temperature leads chiefly to the formation of diacetone alcohol, a small proportion of symmetrical triacetone dialcohol also being formed.Indications have now been found of the presence of a further compound in the condensation product. It is almost certainly unsymmetrical triacetone dialcohol, an unstable substance previously reported solely by Bayer&Co. in 1914.This second trimer has not been isolated and direct evidence of its existence by the infra‐red examination of distillation residue fractions has not so far been obtained. The trimer, however, dehydrates readily to a mixture of two ‘unsymmetrical phorones’. This dehydration product has been isolated in quantity from large‐scale fractions and has been e

ISSN:0021-8871    

DOI:10.1002/jctb.5010130205

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractThe products in the range C4to C10obtained from a series of coals by heating in stages from ambient temperature up to 700° have been analysed by gas‐liquid chromatography. Aliphatic and aromatic compounds are evolved even below 100°. The rates of evolution do not increase regularly with temperature, but show two distinct maxima. Coals of different rank, and different macerals of the same coal, are compa

ISSN:0021-8871    

DOI:10.1002/jctb.5010130206

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

摘要:

AbstractFrom a study of the melting behaviour of binary mixtures of glycerides it is possible to predict the properties of some of those fats and oils which contain such glycerides. The results can be useful in margarine formulation, dry fractionation, and solubility problems connected with the preparation of novel fat blends.The phase behaviour of six binary mixtures of palmito‐oleo triglycerides has been studied. The techniques used included the microscopical observation of melting behaviour,X‐ray powder photography, and differential thermal analysis. In two of the systems, particularly the mixture of 2‐oleodipalmitin and 1, 3‐dioleopalmitin, evidence was found of favourable steric factors leading to closer association of unlike molecules at about 50% concentration. This fact can be used to explain certain phenomena in fat systems such as mixtures of palm oil and lard which contain significant amounts of these two glycerides. ‘Graininess’ and enhanced crystallisation at certain concentration levels are two suc

ISSN:0021-8871    

DOI:10.1002/jctb.5010130207

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY

ISSN:0021-8871    

DOI:10.1002/jctb.5010130208

出版商:John Wiley&Sons, Ltd    

年代:1963

数据来源: WILEY