关于钢铁及制品的说法错误的是( ) A.含有某些金属和碳元素的铁合金,其性能比纯

题型:选择题

问题:

关于钢铁及制品的说法错误的是(  )

A.含有某些金属和碳元素的铁合金,其性能比纯铁更优良

B.高炉中炼铁的主要反应可表示为:Fe2O3+3CO

 高温 
.
 
2Fe+3CO2

C.其它金属单质与铁一样,都能与盐酸反应得到氢气

D.家用菜刀经洗净擦干后可防止生锈

考点:合金金属的化学性质金属的冶炼(铁的冶炼)金属的锈蚀与防护
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两车同向行驶间距不得小于();防爆胶轮车在井下运行过程中,禁止(),严禁()风门。

题型:选择题

阅读理解。

    A recent study, which was published in last week's Journal of the American Medical Association,

offers a picture of how dangerous it is to get a lift from a teenage driver. Indeed, a 16-year-old driver

with three or more passengers has three times the possibility of a serious accident, compared with a

teenager driving alone.

     The authors also found that the death rates for teenage drivers increased greatly after 10 p.m., and

especially after midnight. With passengers in the car, the driver was even more likely to die in a late-night

accident.

     Robert Foss, a scientist at the University of North Carolina Highway Safety Research Center, says

the higher death rates for teenage drivers have less to do with "really stupid behavior" than with just a lack of driving experience. "The basic issue is that adults who are responsible for giving out licenses fail to

recognize how complex and skilled driving is." he says.

     Both he and the author of the study believe that the way to mitigate (使缓解) the problem is to have

states set up so-called graduated licensing systems, in which getting a license is a process with several

stages. A graduated license requires that a teenager first prove himself able to drive in the presence(在场)

of an adult, followed by a period of driving with night of passenger restrictions (限制) before graduating

to full driving rights.

     Graduated licensing systems have reduced teenage driver crashes, according to recent studies.

1.Which of the following situations is most dangerous according to the passage?

A. Adults giving a lift to teenagers on the highway after 10 p.m.

B. A teenager driving after midnight with passengers in the car.

C. Adults driving with three or more teenage passengers late at night.  

D. A teenager getting a lift from a stranger on the highway at midnight.

2. According to Robert Foss, the high death rate of teenage drivers is mainly due to _____.

A. their lack of driving experience

B. their frequent driving at night

C. their wrong way of driving    

D. their driving with passengers

3. According to Paragraph 3, which of the following statements is TRUE?

A. Teenagers should spend more time learning to drive.

B. Driving is a skill too complex for teenagers to learn.

C. Restrictions should be forced on teenagers demanding to take driving licenses.  

D. The licensing department is partly responsible for teenagers' driving accidents.

4. A suggested measure to be taken to reduce teenagers' driving accidents is that _____.

A. the licensing system should be improved

B. they should be forbidden to take on passengers

C. they should not be allowed to drive after 10 pm

D. driving in the presence of an adult should be made a rule

题型:选择题

断肢再移植术:()

A.原位移植

B.异位移植

C.结构移植

D.细胞移植

E.组织移植

题型:选择题

免疫荧光标记技术与酶免疫组织化学技术比较具有的优点()。

A.敏感性更高

B.可用电镜观察

C.便于对细胞微细结构的分辨

D.可同时检测多种抗原

E.染色标本可长期保存

题型:选择题

有关过期妊娠的描述正确的是:

A.平素月经规律,从末次月经第1天起超过40周末临产者

B.平素月经规律,从末次月经第1天起达到或超过40周末临产者

C.平素月经规律,从末次月经第1天起超过42周末临产者

D.平素月经规律,从未次月经第1天起达到或超过42周末临产者

E.以上都不是

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