发电机的外特性是指在发电机的励磁电流、转速和功率因数为常数情况下,()电流和发电机()电压之间的关系曲线。
参考答案:定子、端
The conference will begin in an hour; ,let's have a rest. [ ]
A.on the meantime
B.in the meantime
C.in the meantimes
D.in meanwhile
进口涂料需备案的范围是《商品名称及编码协调制度》中编码为6801.6802项下的商品。 ( )