压力容器封头较多,下列叙述正确的有:()A.凸形封头包括半球形封头、椭圆形封头、碟形

题型:多项选择题

问题:

压力容器封头较多,下列叙述正确的有:()

A.凸形封头包括半球形封头、椭圆形封头、碟形封头、球冠形封头和锥壳。

B.由筒体与封头连接处的不连续效应产生的应力增强影响以应力增强系数的形式引入厚度计算式。

C.半球形封头受力均匀,因其形状高度对称,整体冲压简单。

D.椭圆形封头主要用于中、低压容器。

考点:机械工程过程设备设计过程设备设计题库
题型:多项选择题

下面短文中共有10个错误, 请找出并按要求在文中标记并改正在短文下。

如多一个词:把多余的词用斜线(/)划掉。

如缺一个词:在缺词处加一个漏字符号(∧), 并在下边写出该加的词。

如错一个词:在错的词下划一横线, 并在下边写出改正后的词。

Dear Peter,

I’m glad to know what you have been studying Chinese in an university in Beijing for about one month. Just as you have found, Chinese differ from English greatly. The pronunciation and the spelling of the Chinese words are very complicated, and so is the sentence structures. That is because many people, especially the foreigners, have great difficulty in learning Chinese.

However, practice makes perfect. If you can read and write Chinese as many as you can, you have a good command of it. In addition, you should look for more opportunities to communicate with the native people to get familiar to different accents as well as our cultures, which will help you a lot.

Don’t give up. I’m sure you can learn Chinese well. I can offer you some help if it necessary.

Best wishes!

Yours

Li Hua

题型:多项选择题

肝片形吸虫对牛羊等动物的感染性阶段是:()(767-12)

A、囊蚴

B、尾蚴

C、霄蚴

D、胞蚴

E、毛蚴

题型:多项选择题

万有引力常量G=6.67×10-11______,由万有引力定律可知,两个质量分别为50kg的人,相距2m时的万有引力为______.

题型:多项选择题

大肠癌好发部位是()

A.直肠

B.升结肠

C.横结肠

D.降结肠

E.盲肠

题型:多项选择题

C++ fully supports (73) programming.

A.visual

B.object-oriented

C.logic

D.natural language

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