单元式机组通风机高速运转,但车内风量较小是什么原因?
参考答案:
(1)空气过滤网脏堵;
(2)蒸发器表面结冰或脏堵;
(3)风机反转。
(4)软风道漏风
X和Y均为短周期元素,已知aXn-比bYm+多两个电子层,则下列说法正确的是( )
A.b>5
B.X只能位于第三周期
C.a+n-b+m=10或16
D.Y不可能位于第二周期
If the survival craft is not loaded to full capacity,the personnel should be().
A.loaded more on the port side forward
B.loaded equally on both sides with more forward
C.loaded equally on both sides with more aft
D.allowed to sit anywhere