A New Technique for Following the Attack of Metallic Mirrors by Free Radicals

Abstract

The removal of metallic mirrors is a well-established technique for the detection and identification of free radicals produced in the decomposition of organic compounds. The rate of removal of mirror is usually followed by photometric means, in which the opacity of the mirror is matched against that of a standard. In the course of an investigation into the attack of free radicals on coal and coal by-products at high temperatures, it was found that the evolution of smoke and tarry material tended to make the use of optical methods somewhat unreliable. It was thought that measurement of the electrical conductivity of mirrors could be applied to the problem and, in particular, glass elements of the type used in the measurement of the dewpoint of combustion gases containing sulphur oxides¹ seemed to be ideal for this purpose.