导叶开限有哪些作用?
参考答案:
(1)、运行中限制导叶开度。
(2)、用于开、停机。
(3)、用于控制导叶开度,实现手动运行发电。
She doesn't want to fall behind others. She's ______ to catch up with her classmates. [ ]
A. decide
B. make a decision
C. made a decision
冷冻干燥的工艺流程正确的是()
A.预冻→升华→再干燥→测共熔点
B.测共熔点→预冻→升华→再干燥
C.预冻→测共熔点→升华→再干燥
D.预冻→测共熔点→再干燥→升华
E.测共熔点→预冻→再干燥