解释为什么钡能形成过氧化物而铍则不能。Explain why barium forms peroxide but beryllium does not.然而铍的毒性限制了它的作用.However the toxic properties of beryllium limit its application.但如果用铝包覆铍,则可避免加工过程中及储存期间的中毒问题.Toxicity problem in manufacturing and...
发动机突然反冲.The engine kicked back.警察再次开火，紧抵着反冲机构，不断向袭击他的人射击。The policeman fires again, tensed against the recoil, unleashing round after round at his assailant.我把家伙组装起来，检查了一下击发和反冲机构，装上子弹。I assembled the weapon, checked the ...