On Sunday Cohen lay around the house all day.科恩星期天一整天都在家无所事事。I didn't so much as catch sight of him all day long.我一整天都没见他人影。All day she had fought off the impulse to telephone Harry.她一整天都在克制自己想给哈里打电话的冲动。...
当压力改变时,阀帽容易上下移动.Bonnet tendency to move up or down as pressure changes.阀帽: 不需要将阀门从管路中拆除,就可以进入维护铰链和阀瓣.Cap: permits access to hinge and disc without removing valve from line.止回阀标签通常安置在阀帽的边缘上.Check valve tags are typically ...