Electrode with regulated drop-time

Owing to the compensation of different effects, values for the current received with this type of electrode follow the simple equation of Ilkovic more closely than an ordinary electrode. The Smolef-type of electrode represents a new tool in distinguishing diflferent kinds of polarographic currents. Capillary electrodes with an artificially regulated drop-time also have a similar advantage. 

Even when the derivative current drops to practically zero at the limiting current, the oscillations due to the dropping persists and these oscillations interfere in the measurement of small peaks at more negative potentials. This difficulty can be overcome by using an electrode with a regulated drop-time or a Smolef-type electrode. )... 

Deviation of a capillary from a vertical position changes its drop time considerably. The horizontally positioned DME was originally used by Smoler [9]. Shielding and depletion effects are diminished to some extent, and current oscillations are much smaller. Probably the best performance is observed when the electrode position deviates 45° from the vertical however, opinions about such electrodes vary [10]. In some experiments, electrodes with small mercury flow rates are helpful. For these electrodes, the probability of the appearance of polarographic maxima is diminished. When m is very low, the drop time is usually very long. In such cases, artificial regulation of the drop time should be used (see Sec. II.F). 

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