CORROSION RESEARCH ROUND‐UP

U.S.A. Atmospheric conversion of SO2 to SO3. In the gaseous state, the sulphur dioxide is only very slowly oxidised to sulphur trioxide. It has been recently suggested that in the presence of fog and particulate‐matter catalysts, this oxidation may be greatly accelerated. If oxidation does occur, both sulphate and acidity of the particulate matter should increase. Because nitrate is frequently also present in significant quantities, its relationship to acidity should also be known.