closed in封闭, 包围closedadj.关闭的；封闭的；停业的动词close的过去式和过去分词.closed-celladj.独立气泡的; 密闭气泡的closed vessel[化] 密闭容器closed subset闭合子集closed mining封闭开采closed-loop封闭环Closed colong封闭群closed reflux闭管回流closed filter封闭式滤池,闭滤子closed-down停机closed mixing密炼