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问题 单项选择题

真空管道进行气压试验时，其试验压力应为( )。

A．设计压力的1.0倍

B．设计压力的1.15倍

C．设计压力的1.25倍

D．0.2 MPa

答案

参考答案：D

解析：
[考点] 第二章安装工程施工技术第七节压力试验：管道压力试验
[思路] 真空管道进行气压试验是，其压力规定为0.2 MPa
[易错] 设备压力试验时，气密性试验压力为设计压力的1.0倍；管道气压试验时，承受内压钢管及有色金属管的试验压力应为设计压力的1.15倍；设备压力水压试验时，当设计温度≥200℃时，内压容器的试验压力按Pt＝Ps[σ]/[σ]t计算，其中低、中压设备， Ps按1.25倍的设计压力计算。
[拓展] 考生要熟悉各种压力试验的压力要求。

问答题

右图为某市售盐酸试剂瓶标签上的部分数据．通过计算回答：

（1）求该浓盐酸的物质的量浓度．

（2）用上述浓盐酸和二氧化锰加热反应制取氯气，若生成氯气的体积在标准状况下为4.48L时，则被氧化的HCl的质量为多少克？
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单项选择题

Visitors to this country are normally admitted for six months, but foreign students can usually stay for one year. They must (52) an educational institution, and they are required to study for a minimum of fifteen hours a week on a (53) course. Prospective students have to show that they can afford their studies, and that they have sufficient (54) resources to support themselves (55) in this country.

In order to work here the foreigner needs a work permit, (56) must be applied for by his prospective employer. The problem here is that the Department of Employment has the right to grant or (57) these permits, and there is little that can be done (58) it; it would be extremely unwise for a foreign visitor to work (59) a permit, since anyone doing so is liable to immediate deportation (驱逐出境). There are some people from the Common Market countries, who are often given (60) residence permits of up to five years. Some other people, such as doctors, foreign journalists, authors and others can work without permits, and foreign students are normally allowed to (61) part-time jobs while they are studying here.

52().

A.establish 

B.purchase 

C.prove 

D.attend
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