问题 问答题 简答题

如何消除空压机冷却器内结垢?

答案

参考答案:

空压机冷却器长时间使用后,冷却水中的钙、美等中碳酸盐类物质会在其中形成水垢,水垢会影响冷却器正常的传热,使空压机进、排气温度升高,空气不能被冷却到预定温度,直接影响到生产成本,甚至影响到安全运行。

清洗水垢的办法有两种:一是机械方法,也就是物理清除法;另一种是化学法。

机械方法用铁丝刷或用铁丝扎布条在管内来回的托动,把管内的水垢消除掉。

化学法就是根据水垢一般为碱性物质的特点,用稀盐酸把水垢溶解掉,但是酸的含量不能太高,否则会腐蚀金属。

阅读理解

It seems to be strange to you there is a blind spot(盲点)on the eyes,  Here is an interesting experiment(实验)that can make something disappear, when one eye is open.

Make a card about the size of a postcard and write two English letters L and R on it, Lon the left and R on the right. First, hold the card about 80 cm away and you see both the letters.  Then close your right eye and look at the letter R only with your left eye. And now, as you move the card slowly towards you, you' 11 find the letter L disappearing. But if you move the card nearer to your face, the letter will be seen again. Now do the same experiment with your left eye closed, you'll find the letter R disappearing.

Why does the letter disappear? It is because there is a blind spot on the eye. When the image(影像)of the letter falls on the blind spot,  it won't be seen.  That is why either of the letters disappears.

小题1:The writer of the passage thinks that_______ there is a blind spot on the eye.

A.few people know

B.no one knows

C.only you know

D.all the people know小题2:The word "disappear" in the passage means_______ in Chinese.

A.驱散

B.消散

C.消失

D.遗失小题3:You fail to see the letter L in the experiment because _______.

A.your eyes are poor

B.its image falls on the blind spot

C.your left eye is not open

D.you move it close to your eye小题4:In which order(顺序)should you do the experiment?

①Hold the card ②Move the card nearer ③Close your right eye

④write two English letters ⑤Look at the letter R ⑥Make a card

A.④⑥①②③⑤

B.①③⑥④⑤②

C.⑥①④③②⑤

D.⑥④①③⑤②小题5:The passage mainly tells us_______.

A.how to find the blind spot

B.an interesting experiment

C.where the blind spot is

D.there is a blind spot on the eyes.

单项选择题 A1/A2型题