Abstract: The semiintegral and semidifferential technology was applied to process cyclic oscillochronopotentiometric signal in this paper.The instrument of 3.5th order differential cyclic oscillographic chronopotentiometry has been designed. The experimental results of determination for Cd, In, Rh and Pb in pH=10 HAc-NaAc-0.06% HCup solution show that the method has three advantages: (a) compared with the classifical oscillographic method based on dE/dt～E curve, the sensibility of the new method is increased about 5～10 times; (b) better resolving power; (c) the peak height caused by depolarizer on Y^3.5～E curve is easy to be measured. As a result, 35th order differential cyclic oscillographic chronopotentiometry will become a really feasible analytical method.

Key words: Semidifferential, Oscillographic analysis, Cyclic oscillographic chronopotentiometry