电弧游离方式的热电发射是触头分断电流时,阴极表面由于大电流逐渐收缩集中,而出现炽热的

题型:判断题

问题:

电弧游离方式的热电发射是触头分断电流时,阴极表面由于大电流逐渐收缩集中,而出现炽热的光斑,温度很高,触头表面分子外层电子吸收足够的热能,发射到触头间隙,形成自由电子。

考点:工厂供电考试工厂供电考试题库
题型:判断题

以下对生活中的一些事实解释不合理的是 [ ]

A.铁栏杆上涂油漆是为了防止生锈

B.油锅着火时盖上锅盖是为了隔绝空气

C.热水器安装烟囱是为了防止CO2中毒

D.汽车燃料使用乙醇汽油可以减少空气污染物的排放

题型:判断题

患者男,48岁,1年来每于剧烈活动时或饱餐后发作剑突下疼痛,向咽部放射,持续数分钟可自行缓解。2周来发作频繁且有夜间睡眠中发作,就诊前2h疼痛剧烈,不能缓解,向胸部及后背部放射,伴憋闷,大汗。

该患者首先考虑的诊断是()

A.主动脉夹层分离

B.自发性气胸

C.急性胰腺炎

D.急性肺动脉栓塞

E.急性心肌梗死

题型:判断题

What is your favorite English letter?  Many of you may say Q. Why?  Because

so many of you chat with your friends on QQ. What do you like about QQ?  What do you talk about?  The CCTV reporter,  Miss Wang,  interviews three kids. Let’s listen to what they say.

When do you chat on QQ?  What do you talk about?

 Lin Yuhan,  Xi’an:  On weekends. We talk about homework and chat with each other.

  Tang Xuting,  Shanghai:  At weekends and when I don’t have much homework. We exchange test answers and chat.

Yang Yuhang,  Dalian:  Our class goes online together at 4: 00~6: 00pm on weekends. We complain about homework,  chat and talk about computer games.

  What do you put on your QQ blog(博客)?

  Lin: I put good articles I have found online on my blog. I also write articles myself. They are about funny things that have happened in my class.

 Tang: I put pictures on my blog. Not my own photos,  but pictures from my favorite Japanese cartoons(动画片)like Tennis Prince Conan.

  Yang: I put DV films on my blog. I shoot(拍摄)them during sports meetings and school parties. The most popular one is about a dancing teacher,   he is so funny that everyone watches it.

   How do you like QQ?

 Lin: It’s a good space for us to make a record of our lives of both good times and sad times.

  Tang: My friends and I may not have time to chat at school. But we can do it on QQ. It’s very helpful to our friendships.

  Yang: If you chat with friends on the telephone,  your parents sometimes listen to your conversation. There’s no such problem with QQ. You can relax and talk freely.

小题1:What does Yang Yuhang talk about on QQ on weekends?

①homework     ②chat

③test answers   ④computer games

A.①②

B.②③

C.①②④

D.②③④小题2:What does Lin Yuhan put on her QQ blog?

A.Some pictures.

B.Good articles.

C.DV films.

D.Japanese cartoons.小题3:Which one is TRUE according to this article?

A.Lin says QQ is very helpful to their friendships.

B.Yang says he can chat freely with many friends and relax on QQ.

C.Tang says QQ is a good space for them to make a record of their lives.

D.Tang says he chats on QQ on weekends though he has lots of homework.

题型:判断题

重症肌无力()

A.血清钾降低

B.眼外肌麻痹为首发症状

C.血清肌酸激酶异常增高

D.蓬毛样红纤维

E.皮肤牛奶咖啡斑

题型:判断题

我市医疗保险制度,目前,所有参保人员都享有以大病为主的住院保障和以小病为辅的门诊保障,在全国率先实现了“人人享有医疗保障”的目标,到2011年底,参保人数达到()多万人。

A.300

B.600

C.980

D.800

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