The push rod was screwed into a miniature piston head . 这根推杆拧紧在一个微型的活塞头上。
High-strength bolts were inserted into the holes and tightened to a high preload level . 把高强度螺栓插入孔洞,同时拧紧螺栓达到高的预加载水平。
Water is collected in the 30ml poly bottles in the field and screw-capped ready for future treatment . 水样用30毫升的聚乙烯瓶的野外采集,拧紧螺旋盖以备进一步处理。
I was to keep the fish before me in a tin tray, and occasionally moisten the surface with alcohol from the jar, and always taking care to replace the stopper tightly . 我必须把鱼放在我面前的一个铁盘内,不时地用瓶中的酒精浸湿它的表面,每次还要把瓶塞拧紧。