问题 问答题 简答题

简述蒸汽加热式汽化器的工作原理。

答案

参考答案:

是由蒸汽作为加热剂的汽化设备,从结构上看它由液相段、列管段和气象段3部分组成,是一种列管式设备。壳程的介质为蒸汽,管程介质为液化石油气,其工作原理是液化气由浸没在温水中的不锈钢钢管内通过,吸收蒸汽的热量后汽化并过热,经过气液分离器脱去重组分后输入管网。

单项选择题

I was a single parent of four small children, working at a low paid job. Money was always tight, but we had a (1) over our heads, food on the table, clothes on our backs, and if not a lot, always (2) . Not knowing we were poor, my kids just thought I was (3) . I’ve always been glad about that.

It was Christmas time, and although there wasn’t (4) for a lot of gifts, we planned to celebrate with a family party. But the big (5) for the kids was the fun of Christmas (6) .

They planned weeks ahead of time, asking (7) what they wanted for Christmas. Fortunately, I had saved MYM120 for (8) to share by all five of us.

The big (9) arrived. I gave each kid a twenty-dollar bill and (10) them to look for gifts of about four dollars each. Then everyone scattered. We had two hours to shop; then we would (11) back at the "Santa’s Workshop"

Driving home, everyone was in high Christmas spirits, (12) my younger daughter, Ginger, who was unusually (13) She had only one small, flat bag with a few candies—fiftycent candies I was so angry, but I didn’t say anything (14) we got home. I called her into my bedroom and closed the door, (15) to be angry again. This is what she told me.

"I was looking (16) thinking of what to buy, and I (17) to read the little cards on the ’Giving Trees’. One was for a little girl, four years old, and all she (18) for Christmas was a doll. So I took the card off the tree and (19) the doll for her. We have so much and she doesn’t have anything. "

I never felt so (20) as I did that day.

3().

A.made 

B.searched 

C.bought 

D.fetched

单项选择题