Abstract
Impedance measurements were performed on Na-form cation-exchange resin particles under circulating high-purity water between a pair of platinum electrodes, across which an alternating current was applied. The impedance was measured for frequencies between 1MHz and 20Hz and plotted on a complex plane to produce a straight line with a slope of 45° in the high frequency range. At approximately 60Hz, the impedance suddenly showed an abrupt transition to a second impedance path with a slope larger than 45°. When the impedance was measured by increasing the frequency above 20Hz, the impedance changed along the second path until 150Hz, beyond which frequency it made an abrupt transition to the first impedance path; that is, hysteresis was observed. The effective voltage Eeff of the alternating current was changed from 10mV to 800mV in order to investigate the effects of Eeff on both impedance paths. The results suggest that the second impedance path might be related to a positive feedback process.
