问题 问答题 简答题

交换器内树脂层失水后在启动前应该如何进水?为什么?

答案

参考答案:

应先由交换器上部进水至水位高于树脂层后,改由底部进水至空气阀溢水为止。因为由交换器上部进水时,树脂颗粒间夹杂的空气不能排除,因此必需采用底部进水将空气随上升的水流同时排除。但当交换器树脂层内无水时,由交换器底部进水会因树脂颗粒间的摩擦力使树脂层成一个整体上抬,此时会造成中排装置的弯曲或断裂。

听力题

根据短文内容填写表格(所填内容可能是单词、短语或句子)

March 25 is the 17th National Day of Education on the Safety of Elementary and Middle School Students. The theme (主题)of the day this year is to give students more knowledge about how to keep safe.

How can you keep yourselves safe? Here are some suggestions.

When there is a fire: Shout out “Fire”! Call 119! Try to find a safe exit(出口) and get away quickly. Don’t use a lift. Use a piece of cloth to cover your mouth and nose.

When there is an earthquake at school: Stay calm. Follow the teachers’ instructions. Quickly move under the desk. Don’t jump out of windows or run out.

When you are on the street: Wait for the green traffic light. Look left and right before crossing the street. Don’t run across the street.

When you are eating: Wash fruits and vegetables carefully before eating them. Check the expiration dates(保质期) of the food. Don’t eat the food if it looks or smells bad.

When you are at school: Take care not to fall down or hurt yourself. Don’t run, jump or push while going upstairs or downstairs. Take care of yourself all the time.

Suggestions on      小题1:   

Situations

What you should do

What you shouldn’t do

Be on fire

Shout out “fire”!    小题2:   ! Find a safe exit. Get away quickly. Use a piece of cloth to cover your mouth and nose.

Take a lift.

Have an earthquake

Stay calm. Follow the teachers’

instructions.    小题3:    .

Jump out of windows.

Run out.

Be on the street

Wait for the green traffic light. Look left and right before crossing the street.

     小题4:      .

While eating

Wash fruits and vegetables carefully. Check the expiration dates.

Eat bad food.

While at school

    小题5:   at any time.

Jump, run or push while going upstairs or downstairs.

填空题