double double iron  八叠板

“double-seat double-vote” system  双议席双票制

ball mill with double-inlet and double outlet  双进双出钢球磨煤机

cationic double-chamber double-layer float bed  阳双室双层浮动床

COAL PULVERIZER WITH DOUBLE INLET AND DOUBLE OUTLET  双进双出磨煤机

double blind double dummy  双盲双模拟

Double blind double dummy randomized controlled clinical trial  随机双盲双模拟对照试验

double bus bar with double sectionalized bus bars  双母线双分段接线

Double Busbar and Double Segment  双母线双分段

Double Chambers and Double Layers  双室双层

Double chambers double layers floating bed  双室双层浮动床

double column and double FID  双柱双检测器

Double columns and double FIDs  双柱双检测器

Double Connecting Rods and Double Crankshafts  双连杆双曲轴

double engine and double oar  双机双桨

double entry and double exit  双进双出

double ether double sulfonate  双醚双磺酸钠盐

Double frequency pulsation double vertical ring high gradient magnetic separator  双频脉冲双立环高梯度磁选机

Double Inlet and Double Outlet Coal Mill  双进双出磨煤机