Environmental issues such as global warming due to fossil fuel use are now major worldwide concerns, and interest in renewable and clean energy is growing. Of the various types of renewable energy, green hydrogen energy has recently attracted attention because of its eco-friendly and high-energy density. Electrochemical water splitting is considered a pollution-free means of producing clean hydrogen and oxygen and in large quantities. The development of non-noble electrocatalysts with low cost and high performance in water splitting has also attracted considerable attention. In this study, we successfully synthesized a NiCo2O4/NF electrode for an oxygen evolution reaction in alkaline water splitting using a hydrothermal method, which was followed by post-heat treatment. The effects of heat treatment on the electrochemical performance of the electrodes were evaluated under different heat-treatment conditions. The optimized NCO/NF-300 electrode showed an overpotential of 416 mV at a high current density of 50 mA/cm2 and a low Tafel slope (49.06 mV dec-1). It also showed excellent stability (due to the large surface area) and the lowest charge transfer resistance (12.59 Ω). The results suggested that our noble-metal free electrodes have great potential for use in developing alkaline electrolysis systems.

Insect is an important player in the ecosystem as a prey for animals. Moreover, they are a valuable candidate food source for rearing animal. Tenebrio molitor (Coeloptera: Tenebrionidae) larvae are known as a good food source with high protein, unsaturated fatty acid, minerals. Therefore, it has strong potential to substitute the conventional meat consumption. To utilize T. molitor as a feed, the standard mass-rearing protocol is required. To make standard mass-rearing protocol, we tested different temperature(17.5, 20, 22.5, 25, 27.5 and 30°C) conditions for egg, larvae, pupae and adult T. molitor to identify the optimal rearing condition. Hatching was occurred within 15~32.5°C range. However, 17.5~27.5°C was required to get more than 70 % hatching rete. When the eggs were treated in 22.5~27.5°C, all eggs were hatched within 10 days. As larval development, shorter developmental period, higher pupation and eclosion rates were observed within 25~27.5°C temperature range. In addition, we compared the number of egg, oviposition duration and time required to start egg-laying. The minimum egg-laying(258.40±10.86) was observed at 17.5°C, but the maximum(749.10±7.45) was at 27.5°C. The maximum oviposition duration (137.00±12.73 day (mean±S.D.)) was achieved at 27.5°C, but the minimum (87.50±3.54 day (mean±S.D.)) was at 30°C. The time required to start egg-laying was less than 10 days at 17.5, 27.5, and 30°C. To consider all the factors, we concluded that the optimal temperature is 27.5 °C.

This study was performed to investigate the effects of Needle Electrode Electrical Stimulation(NEES) on ischemia-induced cere˗ brovascular accidents. After obstruction and reperfusion of arteries in white mice, the amounts of necrosis and inflammation related sub˗ stances Bax, IL-6, Caspase-3, and COX-2 were measured in neurons of the fore-brain. The following results were obtained. This study used 21 male specific pathogen free(SPF) SD rats, 8 weeks of age and approximately 300g in weight. Each exposed artery was completely occluded with non-absorbent suture thread and kept in that state for 5 minutes. The sutures were then removed to allow reperfusion of blood. Test group is control group(common carotid artery occlusion models), a GI(underwent common carotid artery occlusion), and NEES(underwent NEES after artery occlusion). The GI and NEES groups were given 12, 24, or 48 hours of reperfusion before NEES. NEES device(PG6, ITO, Japan, 9V, current, 2Hz) was used to stimulate the bilateral acupoint ST36 of the SD rats for 30 minutes while they were sedated with 3% isoflurane. An immuno-his˗ tochemistry test was done on the forebrains of the GI induced rats. Both Bax and Caspase-3 immuno-reactive cells, related to apoptosis, were greater in the GI than the NEES group. Cox-2 and IL-6 immuno-reactive cells, related to inflammation, were greater in the GI and NEES groups than the control group. We can expect that applying NEES after ischemic CVA is effective for preventing brain cells from being destroyed. And we can conclude NEES should be applyed on early stage of ischemic CVA.