相关试题
【判断题】
致使机油乳化的原因,主要是机油内含水量较高。
【判断题】
由于喷油器雾化不良,燃油系统有空气,活塞刮油环反装或刮油性能差,均会导致柴油机冒黑烟。
【判断题】
高温水系统水管上的温度控制阀漏油,会造成油水互窜,导致膨胀水箱有油。
【判断题】
当柴油机冷却水温度超过88℃时,水温继电器动作,通过中间继电器2ZJ的作用,柴油机卸载。
【判断题】
柴油机一发电机组的功率输出端通过传动轴与静液压变速箱连接。
【判断题】
回拉手柄时引起柴油机过载的原因是增、减载针阀开度过小。
【判断题】
在正常情况下,联合调节器内的最高转速止钉丢失时,不会造成飞车事故。
【判断题】
主机油泵出口压力为550kPa时,调整阀开启压力为550kPa。
【判断题】
柴油机在空转时转速正常,加载时转速不正常时,多为喷油泵故障或供油齿条卡滞。
【判断题】
柴油机润滑间隙过大或过小,同样会造成轴颈或轴瓦的拉伤。
【判断题】
柴油机放水后再上水时,必须开放有关排气阀。
【判断题】
一个二极管被击穿短路后,1RD将首先熔断,有时出会出现2RD同时熔断现象。
【判断题】
感应子牵引励磁机的感应电动势是由定子上的电枢绕组产生并输出的。
【判断题】
东风4机车启动接触器QC和主发励磁接触器LC,采用CZO-40/20型电磁接触器。
【判断题】
当机车轮对发生空转时,通过空转继电器线圈内的电流达0.1A时,线圈吸合,空转信号灯亮。
【判断题】
空转继电器的构造与接地继电器相同,动作后能自锁。
【判断题】
东风4机车用TQFR-3000型同步牵引发电机,其定子上设励磁绕组,转子上设电枢绕组。
【判断题】
牵引发电机的励磁由励磁机L供给,L发出的三相交流电经2ZL整流输出直流电,向牵引发电机励磁绕组供电。
【判断题】
运行中蓄电池放电,手按2QA,空压机工作正常说明QF发电。
【判断题】
使用接地开关DK及故障开关GK,均无法消除DJ动作时,属主电路瞬间接地。
【判断题】
蓄电池的电解液是浓硫酸与自来水按一定比例配成的稀硫酸液。
【判断题】
方向转换开关1—2HKf在前进位时,两对辅助触头(267-269)串联后控制走车电路,保证该开关均在前进位,才能接通走车电路。
【判断题】
Rlcfl、Rlcf2整定后,Rgt在减载极限位时CF有最大的励磁电流。
【判断题】
磁场削弱开关XKK置于自动位和手动位都不起作用,说明过渡装置GDZ故障。
【判断题】
柴油机运转时,任意一个增压器机油入口处的压力低于78kPa都会使1YJ或2YJ释放。
【判断题】
柴油机启动后,接地试灯的插头插入插座,对电路没有不良影响。
【判断题】
当机车不能换向而用手扳动换向开关手柄时,必须在机车停车时进行,严禁机车运行时扳动换向器进行换向。
【判断题】
无级调速机车主手柄置于升位,5、6、7号触头闭合,柴油机转速上升。
【判断题】
柴油机启动后,如将试灯插头插入插座,当有关电路发生接地后,有可能发生电气误动作。
【判断题】
任一台牵引电动机故障使用电阻制动时,制动电流不应过大。
【判断题】
无级调速机车主手柄的8号触头,在前三位时闭合,后两位时断开。
【判断题】
机车附挂运行时,做电气动作试验时,应与运行方向相同。
【判断题】
1ZJ在走车电路中的主要功能是防止高位起车。
【判断题】
JZ-7型空气制动机紧急限压阀的制动状态与正在缓解状态通路相同,作用不同。
【判断题】
制动管向工作风缸和降压风缸充气是通过分配阀的副阀部实现的。
【判断题】
机车单独缓解时,JZ-7空气制动机各阀之间的控制关系为:单阀一作用阀一机车制动缸。
【判断题】
JZ-7型空气制动机自阀的作用是通过控制均衡风缸的压力变化,经中继阀的作用来控制制动管的充、排气。
【判断题】
JZ-7型空气制动机自阀手柄在紧急制动位时,其放风阀才被推开。
【判断题】
JZ-7型空气制动机自阀手柄置为过充位时,使制动管得到比规定压力高30—40kPa的过充压力。
【判断题】
局减止回阀的作用是再制动时防止局减室内压力空气向制动管逆流。
推荐试题
【单选题】
14. I don’t know the teacher is talking with Miss Wang.
A. what B. whom C. who D. which
【单选题】
15.Millie does __________ that many people are thankful to her.
A. such an important and helpful job B. so important and helpful work
C. a very important and helpful job D. such an important and helpful work
【单选题】
16. I think eating more vegetables is good _______ our health.
—Yes, I agree _______ you.
A. at, to B. for, with C. to, to D. for, to
【单选题】
17. I often go on holiday with my parents _____ summer.
A. in B. at C. on D. of
【单选题】
18. I called you at 4:00 yesterday afternoon, but nobody answered.
Sorry, I ______ with my friends at that time.
A. had swum B. swam C. would swim D. was swimming
【单选题】
19.––Who is on the playground? ---__________.
A. Never B. None C. No one D. A lot
【单选题】
20. The schoolboy ______ a blind man cross the street yesterday.
A. helps B. helped C. will help D. has helped
【单选题】
21. —The 2010 World Expo which will last 184 days will be held in Shanghai on May 1st.
—________exciting news! We shall try our best to support it.
A. How B. How an C. What D. What an
【单选题】
22. They preferred ______ in bed rather than _____ horses.
A. to lie; to ride B. lying; riding C. lying; ride D. to lie; ride
【单选题】
23. —What was Jim wearing at the party?
— Nothing _______. He was in his usual shirt and jeans.
A. special B. simple C. important D. interesting
【单选题】
24. The 2016 Olympic Games ________ in Brazil. Would you like to go there?
Maybe, if possible.
A. are held B. will be held C. were held D. have been held
【单选题】
25. — David, look at the man in white over there.Can you tell me _______ ?
—He is a doctor.
A. who is he B. who he is C.what does he do D. what he does
【单选题】
( ) 26.With help from a Mr. H, you can__________.
A. stop wearing your watch B. get new books and objects
C. finish your homework on time D. know when parents or teachers are near
【单选题】
( ) 27. A PENGO WATCH CONTROL can help you to ______________.
A. repair your TV B. put away your books and objects
C. become a James Bond D. get a daily weather report
【单选题】
( ) 28. You can get your Mr. H for___________.
A. $299 B. $499 C. $199 D. $99
【单选题】
( ) 29. When was canned food invented?
A. In 1870. B. In 1810. C. In 1902. D. In 1926.
【单选题】
( ) 30. After the trip to the Arctic, Clarence Birdseye invented ____________.
A. canned food B. can openers
C. frozen food D. air conditioning
【单选题】
( ) 31. Changes in weather _____________ in Willis Carrier's company.
A. helped to keep food B. made rooms comfortable
C. caused health problems D. hurt printing paper
【单选题】
( ) 32. According to the passage, which of the following may lead to inventions?
A. People's needs. B. Public support.
C. Modern technology. D. Practical suggestions.
【单选题】
( ) 33. What is the writer's main purpose(目的)in writing this passage?
A.To tell the readers his life story.
B.To tell people what kind of person his father was.
C.To tell the readers what present he got from his father.
D. To let people know how poor he was.
【单选题】
( ) 34. Why did the father not ask his son not to do this and do that?
A.Because he felt quite confident of his son.
B.Because he was born from a poor family.
C.Because he was a man of few words.
D.Because he didn't want to be much too strict with his son.
【单选题】
( ) 35. What would someone learn from this passage?
A.How to live by oneself. B.How to stand on one's own feet.
C.What a good father should do. D.What the self-important is like.
【单选题】
( ) 36. What may be the proper Chinese for the underlined part in the passage?
A.闲暇时光 B.学费 C.精神空虚 D.经济不足
【单选题】
( ) 37. The Chinese Yellow Sea Wetlands are in the _______ of China.
A.south B.east C.west D.north
【单选题】
( ) 38. Usually the weather in the wetlands is _______.
A.hot B.pleasant C.cold D.dry
【单选题】
( ) 39. The World Wetlands Day is on _______.
A.February 2 B.June 25 C.April 22 D.March
【单选题】
( ) 40. We must protect wetlands because _______.
A.they are home for wildlife B.they can prevent flood
C.they can offer food to the animals and birds D.all of the above
【单选题】
) 1. —Is it far from here to the bank?
—Not very, only________.
A. 20 minute’s walk B. 20 minutes walk
C. 20 minutes’ walk D. 20 minutes’ walks
【单选题】
2. — After discussing, the students ________ some good ideas to work on the project.
— Thats great!
A. put up B. set up C. caught up with D. came up with
【单选题】
3. Yesterday Tommy walked past my table and ______ my bowls and dishes.
He should be careful next time.
A. knocked off B. took off C. showed off D. turned off
【单选题】
4.We don’t have enough nurses to look after patients.At least ___ nurses are needed.
A. ten another B. more ten C. another ten D. other ten
【单选题】
5. — Zhao Rui, it’s said that many famous singers will come to Yangzhou on April 18th. How about watching the evening show there?
—________! Let’s ask Huang Tao to go with us.
A. Best wishes B. Sounds great C. Good luck D. That’s OK
【单选题】
6.—Hello! This is Henry Speaking.I’d like to speak to your father.
—Sorry, he has Shanghai.
A. been in B. been to C. come to D. gone to
【单选题】
7. — It’s difficult for the village children to cross the river for school.
— I think a bridge ______ over the river.
A. was built B. is being built C. has been built D. should be built
【单选题】
8. —Where would you like to go, Jinan or Qufu?
— .I only want to go to Qingdao.
A. Each B. Either C. Neither D. All
【单选题】
9 — The documentary A Bite Of China II is quite popular around China recently. How do you like it? ______.
A. I think so B. Pretty good C. Its my pleasure D. All right
【单选题】
10. There are three English-books on the shelf, but ______ of them is mine.
A. both B. neither C.all D. none
【单选题】
11. When the parents arrived at the hall, the students _______ their projects.
A. have finish B. finished C. had finished D. are finishing
【单选题】
12. This week, the _______ seems to change every day: one day is hot; the next day is cold.
A. time B. weather C. season D. way
【单选题】
13. He never does his work _______ Mary.
A. as careful as B. so careful as C. carefully as D. as carefully