抽气泵的排气管应该导向室外空旷处或导向一座通风橱.The pump exhaust should lead to the open air or a fume hood.设计了一套硅片专用真空夹紧装置,包括夹紧装置和微型无油真空抽气泵.A vacuum clamp equipment used for holding Si wafer is designed in this paper....
小儿子是天生的流浪儿.The youngest is a born rider of the rails.小儿子是个天生的流浪儿.The youngest is a born rider of rails.这个流浪儿以前从没听过这样的话, 这也是他有生以来听到的最快乐的话.These were strange words to the vagabond boy's ears, and the pleasantest he ha...