Electrochenucal methods were followed m the preparatron of a-and p-PbO, by super-"nposmg ac on dc. The samples obtained wtth dttferent proportrons of ac were analysed chemrcally, therm0 vunetrtcally and by X-ray d&a&on. In t!za e case of /I-PbO, the percentage ac supernnposed increases the formation
Effect of superimposition of ac on dc in the anodic polarization of cadmium in potassium hydroxide solution
โ Scribed by K.P. Rao; P.V.V. Rao; H.V.K. Udupa
- Publisher
- Elsevier Science
- Year
- 1967
- Tongue
- English
- Weight
- 250 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0013-4686
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โฆ Synopsis
Considerable work on the anodic polarization of cadmium by potentiostatic and galvanostatic techniques has been reported in the literature. Th.e effect of ac superimposed on dc in such a study has now been carried out. The results show that ac superimposition lowers the passivation time as well as the passivation potential; and at the same time the weight loss is lowered. An explanation is given for the passivation observed under (conditions of ac superimposition.
R&urn&-Un nombre considerable de travaux sur la polarisation anodique du cadmium par des techniques potentiostatiques et galvanostatiques se trouvant dans la litterature. L'effet d'un courant altematif superpose au courant direct dans une telle etude est ici envisage. Les resultats montrent que la superposition dun ca diminue le temps de passivation aussi bien que le potentiel de passivation; en mCme temps, la perte de poids est diminuee. Une explication est propode pour la passivation observee dans de telles conditions de superposition d'un courant alternatif. Zusammenfassung-In der Literatur tindet sich eine ansehnliche Zahl von Arbeiten tiber die anodische Polarisation von Kadmium mittels potentiostatischer und galvanostatischer Methoden. In der vorliegenden Arbeit wurde der Einfluss von dem Gleichstrom tiberlagertem Wechselstrom bei diesem System untersucht. Die Ergebnisse zeigen, dass die Ueberlagerung von Wechselstrom sowohl die Passivierungszeit als such das Passivierungspotential erniedrigt; gleichzeitig nirnmt der Gewichtsverlust ab. Man gibt eine Erkllrung ftir die bei Wechselspannungstiberlagerung vorkommenden Passivierungsphanomene.
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