Rehearsal and verbal reminders in facilitating compliance with safety rules

Accidents and incidents often occur, because a basic and seemingly simple rule is ‘forgotten’, either unintentionally (error, lapse) or with some degree of deliberate negligence (violation). The present experiment examined the utility of a rehearsal and a last-minute reminder in reducing the magnitude of deviations from an important safety rule by qualified, but relatively inexperienced pilots, specifically, remaining above an altitude of 500-ft. A single rehearsal flight entailing a search for a target on the ground increased the minimum altitude in later flights, but this positive effect did not completely generalize when the target on the ground was changed. These results suggest that the rehearsal flight was encoded in a context-specific manner. The addition of an explicit, last minute reminder about the mandated minimum altitude just before each test flight failed to significantly alter the pilots’ behavior. The results are discussed with respect to their theoretical and practical implications.     

Effects of poisoning gases on and restoration of PdCuSi metallic glass in a capacitive MEMS hydrogen sensor

We investigated the effects of poisoning and restoration of PdCuSi-metallic glass (MG), which is a sensing material that offers low power consumption and fast response times when used in capacitive MEMS hydrogen sensors. Four poisoning gases were used: hexamethyldisilazane (HMDS), H₂S, SO₂, and NO₂. Exposure to H₂S resulted in metal sulfide forming at the surface of the PdCuSi-MG, although the sulfur did not diffuse into the PdCuSi-MG. Exposure to NO₂ only resulted in the nitrogen being adsorbed without bonding to metals. The poisoning elements were desorbed by heating. Exposure to H₂S and SO₂ degraded the hydrogen sensitivity in terms of resistance of the PdCuSi-MG, although exposure to HMDS and NO₂ only slowed down the response time. These degradations were recovered by heating. We next examined forming a refresher layer under PdCuSi-MG in a hydrogen sensor. The hydrogen sensitivity of the H₂S-exposed hydrogen sensor was restored by performing a refresh operation for a few minutes.     

生物化学“知识竞赛式”课程教学实践与体会

本文根据举办生物化学趣味知识竞赛复习课的教学实践,分析了知识竞赛集知识性、趣味性、挑战性等于一体特点,指出它能大大激发学生的学习热情,引导学生愉快地进入自主探索复习状态,是一种新型实用的复习教学方式,并进一步对趣味知识竞赛的组织、实施过程及其应用前景进行了较为详细的介绍和描述。