double tapph.doubleadj.双重的；成双的；两倍的v.翻一番；使 ... 加倍n.两倍；双份double cotton-covered wire双纱包线double-optimization design双重优化设计double conical rotary vessel双锥转鼓double threshold alternating双阈值交替double axle ditching machine双轴开沟机double-hybrid rice strains两系法杂交水稻double outlet left ventricle左心室双出口double-base junction diode单结晶体管double-circular-arc gear双圆弧齿轮double-coated X-ray film双涂层X射线照相片