根据传热管排列不同分为淋水式冷凝器和螺旋管式淋水冷凝器,其中由无缝钢管弯制成螺旋形管

题型:单项选择题

问题:

根据传热管排列不同分为淋水式冷凝器和螺旋管式淋水冷凝器,其中由无缝钢管弯制成螺旋形管组装而成的称为()冷凝器。

A、螺旋管淋水式

B、淋水式

C、横管淋水式

考点:动力与电气工程制冷与空调设备安装修理技术制冷与空调设备安装修理技术题库
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有关HIV感染的正确概念是()

A.HIV只感染CD4T淋巴细胞

B.HIV侵入人体后不能刺激机体产生抗体

C.要是血清抗-HIV阳性病人就无传染性

D.在血清中有抗体和病毒同时存在的情况下,此血清仍有传染性

E.抗-HIV阳性的血液经过56℃,30分钟处理后,仍然有传染性

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钢轨分级使用包含两个方面的含义:钢轨的二次或多次使用和钢轨在一次使用中的()使用。

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阅读理解。

     There are many idioms in English that are about animals. Today let's chat a little about some of the idioms

about dogs that make English language fun and colorful. We love dogs; they are our best friends. When you

first started to learn English, your teacher might teach you a number of phrases about dogs, such as: "you are

a lucky dog," "I'm dog tired," "every dog has its day," or "our team was the underdog but won the first place

at last."

     When I first got into high school, my English teacher used the idiom "dog-ear", which interested me very

much. This word can be used as a noun, a verb, and an adjective as well. As a noun, it means a turned-down

(折叠的) corner of a page as a bookmark. As a verb, it means someone makes a bookmark by turning down

the corner of a page in the book. And, as an adjective, the word describes an old book with many broken

pages. Examples: John made a dog-ear (noun) of the page he was reading before closing the book. Jane was

reading a book; when the telephone rang, she dog-eared (verb) the page before answering the phone. In the

old room, the children found some dog-eared (adjective) books left there for more than 30 years.

1. Which of the following can be the best title of the passage? [ ]

A. Idioms about colors.

B. Idioms about history.

C. Idioms about animals.

D. Idioms about dogs.

2. How many idioms about dogs are mentioned in this passage? [ ]

A. 3.

B. 4.

C. 5.

D. 6.

3. Which of the following statements is NOT true about the meaning of the idiom "dog-ear"? [ ]

A.It means a turned-down corner of a page as a bookmark..

B.It means someone makes a bookmark by turning down the corner of a page in the book.

C.It means an old book with many broken pages.

D.It means something is short and small ike a dog's ear.

题型:单项选择题

结构相似、在分子组成上相差一个或若干个CH,原子团的物质互称为同系物。( )

题型:单项选择题

《国民经济行业分类》中行业分类标准共分为96个大类,96个大类代码用两位阿拉伯数字01到%表示。

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