高速钢在550~570℃下进行三次回火,回火后的组织为()A.回火马氏体+细粒碳化物

题型:单项选择题

问题:

高速钢在550~570℃下进行三次回火,回火后的组织为()

A.回火马氏体+细粒碳化物+少量的残余奥氏体

B.回火马氏体+细粒碳化物

C.回火马氏体+少量的残余奥氏体

D.回火马氏体

考点:轮机工程工业用钢、合金钢、铸铁工业用钢、合金钢、铸铁题库
题型:单项选择题

已知集合M={x|x>0},N={x|lnx>0},则M∩N=______(填“M”、“N”、“空集φ”)

题型:单项选择题

词汇

1. The children are making so much       (声音) outside. Please tell them to be quiet.

2. As we all have grown up, we should learn to look after       (自己).

3. Your mother is so tired that she fall      (睡着的) sitting in her chair .Don't wake her up.

4. I want to visit the Summer Palace. It's a pleasure to walk slowly around the big lake and feel the       (美丽) of the old park.

5. -Ann, I am worried I'm getting fatter. What shall I do?

    -I think you should eat       (少) food and do more exercise.

6. You'll feel much       if you do more exercise. (健康)

7. His sudden      (死亡) surprised his friends.

8. My office is just on the      (five) floor of the building, so I don't go up and down in a lift.

9. Our government has realized the       (important) of education and decided to spend more money on it year by year.

10. The baby stopped       (cry) at once and began to laugh when she saw her mother.

11. There are so many people in the centre of the city at weekends. I would rather stay at home than    (go) shopping.

12. It's pleasant to live in      houses near the sea.(wood)

13. Thank you for       (agree) to let me go on the trip.

14. Wolves are in danger because of the      (lose) of their living areas.

15. The children screamed with      (excite)when they saw their favourite characters.

题型:单项选择题

如图所示的电路中,各个元件均能正常工作.当开关闭合后,下列说法正确的是(  )

A.两表指针均有明显偏转

B.两表指针均几乎不动

C.电流表指针有明显偏转,电压表指针几乎不动

D.电压表指针有明显偏转,电流表指针几乎不动

题型:单项选择题

个体对学习活动所要达到目标的主观估计称为( )

A.学习兴趣

B.学习期待

C.学习动机

D.学习目的

题型:单项选择题

DD公司对其配送中心第二季度服务质量进行了考评。配送中心第二季度共配送1200次,满足程度90%,其中按交货期交货1008次,则交货水平指标达到( )。

A.76%

B.82%

C.84%

D.93%

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