三分法    threefold division

三次对称    threefold symmetry

三指数标志法    three-index notation

三层粘土矿物    three-layer clay mineral

三层问题    three-layer problem

三级定址    three-level addressing

三用的    three-operating

三上四下罗拉牵伸    three-over-four roller drafting

三元系统    three-part system

三相边界    three-phase boundary

三相交流电动机    three-phase current motor

三相感应电动机    three-phase induction motor

三相界线    three-phase interline

三相接触点    three-phase junction

三相接触线    three-phase line of contact

三相径向锥进    three-phase radial coning

三相饱和度    three-phase saturation

三相电源    three-phase supply

三相电压    three-phase voltage

三加一地址指令    three-plus-one address instruction

三点定位    three-point fix

三点交会    three-point intersection

三点反演    three-point inverse

三点调平装置    three-point leveling system

三点算子    three-point operator

三牙轮扩眼器    three-point roller reamer

三足支架    three-point support

三脚井架    three-pole derrick

三螺杆泵    three-screw pump

三分眼器    three-slot receptacle

三级分离    three-stage separation

三头螺纹    three-start screw

三态的    three-state

三态缓冲器    three-state buffer

三投开关    three-throw switch

三管泵    three-tube pump

三效尾气净化催化剂    three-way catalyst

三通换向阀    three-way diverter valve

三通电磁阀    three-way solenoid valve

苏氨酸    threonine

极限老化期    threshold aging period

门限钻压    threshold bit weight