As a sterilization method for a food, heat sterilization, chemical sterilization and the like are available. However they cause the change of the quality and flavor of the food. As the solution, the sterilization method by intense pulsed high electric field (IPEF) has been studied. IPEF sterilization are possible to do non-thermal sterilization of the foods since it destroys the cell membrane of bacteria physically. In this study, we have attempted to apply the IPEF sterilization for green juice. The development of a circulation sterilization system for a practical test was carried out. It was confirmed that enzyme included in the green juice was not deactivated when IPEF was applied. As a result, at applying 20-minute pulse electric field in 30 and 40 kV/cm, survival ratios of viable bacteria in the green juice were reduced to about 40% and 12%, respectively. Also deactivation of Superoxide dismutase (SOD) did not occur when the bacteria were sterilized.

In order to investigate a material transformation of alumina (Al₂O₃) and an influence on leakage current by application of high DC voltage at high temperatures, the leakage current of two alumina samples were measured for 100 hours and the elemental analyses were carried out. The leakage current tended to decrease, and the electrical conductivity decreased with increasing applied voltage. The activation energies of electrical conduction of two samples were nearly equal. Thus, the reproducibility of these results was confirmed. After the experiments, deposits of impurities contained in alumina were observed in the surrounding area of the positive electrode. Furthermore, Na, which was contained in Pt paste used for preparing the electrodes, can be a charge career of alumina because it was detected from only negative electrodes. Therefore, the reason why the leakage current decreased is the decrease in the amount of charge careers because of the deposits of impurities.

Recently, smartphones and tablets are increasingly used instead of desktop computers to access web-pages. This paper discribes the development of cross-platform e-learning system for electric circuits. The implementation is done by HTML5 and JavaScript which is available on web browsers.