问题 问答题 简答题

为什么停车后要立即关闭CO2进口大阀和油冷器冷却水进口阀?

答案

参考答案:

由于压缩机汽缸温度很高,尤其二段温度达215℃以上,当停车以后,如不及时关闭CO2进口大阀,冷CO2进入缸体,将使转子、叶轮等部件产生急剧收缩,同时潮湿的CO2也会给碳钢设备和管道带来危害。

在机组运行时,轴和轴瓦工作在较高温度下。停车后,如不关闭油冷器的冷却水进口阀,将使油温骤降,轴瓦急剧收缩,而轴收缩较慢,会产生抱死现象,而损坏轴瓦。

阅读理解

阅读理解。

     You're sitting on the train home and the person opposite you yawns (打哈欠). Suddenly, you're

yawning with him, though you're not tired.

     This phenomenon confused scientists for years until a recent study found that people tend to

sympathize with fellow humans. Supporting this claim was the discovery that those children who were

unable to form normal emotional ties with others did not experience contagions (有感染力的) yawning,

which showed that humans communicate regularly without words.

     Hogo Critchley, a neuroscientist, has conducted an experiment recently, which will prove that

happiness and sadness can spread like the common cold. According to Critchley, our mind and body

are in constant exchange about how we're feeling. "Emotions are closely linked with states of internal (内

部的)responses, "he explained. "There are also more visible changes in our gesture and facial expressions. When we're in a group, these signals can spread to another person. For example, there's the obvious

tendency to smile when smiled at and there are less obvious changes that reflect emotions of surprise,

anger or sadness such as a change in our heart rate and blood pressure. "

     Hugo Critchley further explained, "Our bodies synchronize and when we like the other person, we

even copy his behivour. Next time you chat with a friend, take note of how you're sitting-it's pretty likely

that you will be the same. Scientists believe it's our way of telling each other that we're partners. Through

body language, humans give each other very subtle (微妙的) but clear signals that show emotions. "

So, what lessons can we learn from this? "Spend time with happy people-otherwise your health could

suffer, " said Critchley. "When we're sad, our body goes into fight or flight mode. But when we're happy,

our body works normally and we feel relaxed and positive. So we look bright, our skin glows, we feel

healthy and it affects everyone around us. "

1. According to Hogo Critchley, _________.

A. emotions are as visible as facial expressions

B. we yawn more frequently when we have a cold

C. emotions are connected with states of internal responses

D. the change of blood pressure is not linked with the change of emotions

2. The underlined word "synchronize" in paragraph 4 means "_________".

A. move slowly    

B. change rapidly  

C. relax temporarily  

D. respond accordingly

3. From the passage we can learn ______.

A. sadness is as contagious as happiness

B. anger is less contagious than friendliness

C. surprise is more contagious than smile

D. surprise is the most contagious among emotions

4. Which of the following statements is true according to the passage?

A. Emotions have delicate influence on fellow humans.

B. Children like copying the actions of the fellow humans.

C. Scientists are still confused about contagious yawning.

D. People tend to communicate more with body language.

单项选择题