泵在封闭运行时,()会全部转变为热能,对泵内存的少量液体加温,使泵体温度随之迅速上升。
A.轴功率
B.有效功率
C.效率
D.损失功率
参考答案:D
4. It used to ______ that humans and animals were different and had little in common.
A.believing
B.be believed
C.believe
D.Believed
血清铁蛋白减低见于()
A.炎症
B.肿瘤
C.白血病
D.恶性贫血
E.营养不良