The forced contact tests at 54mg/m2 showed that KT50 was 6.2 min for Periplaneta americana and 6.0 min for Blattella germanica.是什么意思_The forced contact tests at 54mg/m2 showed that KT50 was 6.2 min for Periplaneta americana and 6.0 min for Blattella germanica.在线翻译_英语_读音_用法_例句