问题 问答题

硅酸盐水泥的矿物组成有哪些

答案

参考答案:硅酸盐水泥的矿物组成,即主料在煅烧过程中其各种原料首先逐步分解为氧化钙、氧化硅、氧化铝及氧化铁。在更高的温度下,这些氧化物相化合,形成以硅酸钙为主要成分的熟料矿物。为得到具有合理矿物组成的水泥熟料,这四种主要的化学成分应控制在如下范围:
氧化钙(CaO) 64%~67%
氧化硅(SiO) 21%~24%
氧化铝(Al203) 4%~7%
氧化铁(Fe203) 2%~5%
此外,熟料中的有害成分游离氧化镁的含量不得超过5%。

阅读理解

When Kyle walked into Ernie’s Pet World, he looked very anxious. The shop owner, Ernie, jumped out of his seat to greet Kyle. He was the shop’s first customer of the day.

“Good morning, sir!”Ernie said,“What can I help you with?”

“Well, I……”Kyle started to say.

“Wait, don’t tell me,”Ernie stopped him.“You’re looking for a …a little dog… for your daughter’s birthday, Right?”

“Not really, I just….”

Ernie didn’t let him finish. “Ah, I’ve got it, You just moved to a new office, and you want some fish for it, I have some very nice fish bowls over here.”

“In fact, I…”Kyle was starting to look very nervous and strange.

“No fish? Ah, a cat! You look like a cat person. At Ernie’s Pet World, we have the best cats. Take a look at this lovely one with long, white hair, She’s looking at you. She’s thinking,‘Take me home. Take me home.’Would you like some cat food and toys, too?”

“No,thank you,”Kyle said.By this time, he was walking up and down. He had a terrible look on his face.“Really, I’m not interested in cats or fish or little dogs.”

“What do you want, then?”Ernie asked.

Kyle looked like he was going to cry.“I just want to know if I can use your toilet!”he said at last.

小题1:Which is TRUE about Ernie’s Pet World?

A.It has many workers.

B.Kyle goes there often.

C.It sells school things.

D.Ernie is the owner of the shop.小题2:What kind of person is Ernie?

A.Very lazy.

B.Rather shy.

C.Over warm-hearted.

D.Not friendly.小题3:Kyle went into the Ernie’s Pet World to          

A.buy a little dog

B.take fish home

C.meet the shop owner

D.look for a washroom小题4:What does the underlined word“anxious”mean?

A.焦急的

B.兴奋的

C.生气的

D.失望的小题5:What is the best title(标题) of the story?

A.Kyle and Ernie

B.Pet or Toilet

C.A Pet Lover

D.A Busy Pet Shop

单项选择题