V K Venkatesan
Articles written in Proceedings – Section A
Volume 49 Issue 3 March 1959 pp 129-135
The effect of sodium dioctysulphosuccinate on the differential capacity of dropping mercury electrode in 0.1 M KCl solution is studied. It is observed that at the desorption potential, vigorous directed movement of liquid occurs at the mercury-aqueous interface. This movement is shown to be responsible for the desorption peak in the differential capacity-potential curve.
The cause of the directed movement is further examined. Arguments are given to support the ideas of Doss and Kalyanasundaram, that the movement is caused by the emerging surface of mercury having a different interfacial tension from that of the older surface, and that the shielding effect of the capillary postulated by Stackelberg does not appear to play an important part either in the production of the desorption peak or the polarographic maxima.
It is found that the directed movement of liquid occurs although to a less extent at potentials far removed from the desorption potential. This results is of great significance in that it points at the importance of looking for such movements before interpreting quantitatively the data obtained with a dropping mercury electrode.
Volume 50 Issue 4 October 1959 pp 272-281
The study of adsorption by the alternating current polarographic method is known as ‘tensammetry’. This technique has been extended to the study of the adsorption characteristics of organic corrosion inhibitors with a view to elucidate the mechanism of inhibition by such compounds. The usefulness of such studies in elucidating the mechanism of inhibition by dicyclohexylamine nitrite, which is now widely used as a vapour phase corrosion inhibitor, is brought out. For this purpose, results obtained by tensammetric studies have been compared with potential measurements on the one hand and direct corrosion tests on the other and discussed.
Volume 54 Issue 2 August 1961 pp 109-115
Adsorption of thiourea and some of its derivatives at the mercurysolution interface has been studied by the tensammetric technique. It has been found that adsorption of thiourea increased the differential capacity rather than decreasing it. However the adsorption of S-methyl derivative of thiourea decreased the differential capacity. The N-substituted derivatives depressed the tensammetric curve of the supporting electrolyte to a greater extent than the N, N1-substituted derivatives. The different behaviours of thiourea and its derivatives are discussed.