润滑油变质的现象有哪些?

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问题:

润滑油变质的现象有哪些?

考点:常减压装置考试初级常减压装置初级常减压装置题库
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阅读理解。

     Dick was born in a poor family. His father had a small boat and went fishing in the morning and sold

the fish in the market in the afternoon. Then he bought some food for his family. When winter came, they

were often hungry. One morning the hungry man fell into the river and wasn't found. Dick's mother left

her three-year-old son without saying good-bye. His aunt had to look after him.

     Twenty years passed. Dick became a tall, strong man. He found work on a farm. He worked hard

and wanted to get more money. He often went to see his aunt with some nice presents. The woman was

very happy but one day she died in a traffic accident. The young man was very sad. After he buried her,

he decided to buy a beautiful tombstone(墓碑)for her. He went to town and came in a shop, but all the

tombstones were too expensive. He asked, "Do you sell an old tombstone, sir?" "Yes, we do, sir, "

answered the shopkeeper. "Is it as expensive as the new one?"

     "No, it's much cheaper," said the man. "But another name was engraved (刻) on it." "It doesn't matter,

" said Dick. "My aunt couldn't read. "

1. If     ___ , the family members were hungry.

A. Dick's father could catch no fish in winter  

B. Dick's father had a boat in winter

C. Dick's father had to look after him in winter  

D. no food was sold in winter

2. The woman had to look after Dick because  __     .

A. she was rich            

B. his father asked her

C. she was kind-hearted    

D. the boy loved her

3. Dick wanted to get more money to     __ .

A. marry a wife            

B. give his aunt nice presents

C. buy a farm              

D. build a house

4. Dick often went to see his aunt because       _ .

A. she felt lonely          

B. she was often ill

C. she had no children      

D. with her help he grew up

5.Dick wanted to buy an old tombstone because  __  _ .

A. he had enough money to buy a new one

B. his aunt couldn't read whose name was engraved

C. his aunt wasn't going to mind it    

D. nobody knew what his aunt's name was

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如图3.7.2.8所示,某墙下条形基础,底宽2.5m,板高350mm,埋深1m,fT=1.1N/mm2,相应于荷载效应基本组合时轴向力设计值F=200kN/m,则墙与基础间抗冲切承载力为()kN。()

A.300.3

B.231

C.269.5

D.350.35

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A.乙醇+水

B.乙醇+甲醇

C.乙醇+乙醚

D.乙醚+水

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