凝汽器在排汽口处的若干排冷却水管最好采用()的排列方式,以防止产生过大的汽阻和得到较

题型:单项选择题

问题:

凝汽器在排汽口处的若干排冷却水管最好采用()的排列方式,以防止产生过大的汽阻和得到较好的传热效果。

A.三角形

B.正方形

C.向心辐向

D.转移轴线

考点:汽轮机辅机值班员汽轮机辅机值班员(高级)汽轮机辅机值班员(高级)题库
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用括号里词的适当形式填空:

1. Please remember ______ (close) the doors when you leave.

2. There ______ (be) a fashion show in our school next week.

3. How I wish _____ (be) a scientist when I grow up!

4. Millie always _____ (walk) the dog in the evening.

5. My father likes eating _____ (dry) fish very much.

6. Would you like _____ (swim) with us?

7. A cat is _____ (lie) under the tree.

8. _____ (eat) healthy food makes you keep fit.

9. We go boating _____ (two) a week.

10. Stop _____ (talk), please. Listen to the teacher carefully.

11. One of the boys in our class is _____ (dress) up in white trousers.

12. Don't put these books on those _____ (shelf).

13. She can sing _____ (good) than you.

14. He always spends much time _____ (play) computer games.

15. This football is expensive. Do you have a _____ (cheap) one?

题型:单项选择题

找出南极洲和北冰洋的相同点和不同点

地区纬度位置半球位置跨经度气候特点代表动物
南极洲______________________________
北冰洋______________________________

题型:单项选择题

如图所示,P、Q为水平面内平行放置的光滑金属长直导轨,间距为L1,处在竖直向下、磁感应强度大小为B1的匀强磁场中。一导体杆ef垂直于P、Q放在导轨上,在外力作用下向左做匀速直线运动。质量为m、每边电阻均为r、边长为L2的正方形金属框abcd置于竖直平面内,两顶点a、b通过细导线与导轨相连,磁感应强度大小为B2的匀强磁场垂直金属框向里,金属框恰好处于静止状态。不计其余电阻和细导线对a、b点的作用力。

(1)通过ab边的电流Iab是多大?

(2)导体杆ef的运动速度v是多大?

题型:单项选择题

避免颅内压突然增高的措施有()

A.保持呼吸通畅

B.保持大便通畅

C.控制咳嗽

D.控制癫痫发作

E.妥善保护,加以约束

题型:单项选择题

高层建筑管道施工中,“三具”指的是()。

A.量棒

B.定位模具

C.控制样棒

D.测量工具

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