为什么说铝在很多介质中耐腐蚀,而在强碱性溶液中不耐腐蚀?

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问题:

为什么说铝在很多介质中耐腐蚀,而在强碱性溶液中不耐腐蚀?

考点:电力生产“1000个为什么”化学运行与检修化学运行与检修题库
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若A点坐标为(1,1),F1是5x2+9y2=45椭圆的左焦点,点P是椭圆的动点,则|PA|+|P F1|的最小值是_______    ___

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设双曲线C:
x2
a2
-y2=1 (a>0) 与直线 l:x+y=1
相交于两个不同的点A、B.
(1)求a的取值范围:(2)设直线l与y轴的交点为P,且
PA
=
5
12
PB
.求a的值.
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阅读理解。

     Narcissus was a beautiful looking boy. He had long, flowing, blond hair, beautiful, bright, blue eyes and

even, white teeth. Many young ladies fell in love with him including the nymph (女神): Echo.

     Nymphs were lively spirits who lived near streams and lakes and protected trees in the forest. Echo had

upset the Queen of the Gods: Hera. As a punishment Hera made Echo unable to speak except to repeat the

last three words of the person she was talking to.

     Poor Echo fell in love with Narcissus but could never tell him how she felt. Narcissus teased her and she

ran away with tears pouring down her face. Aphrodite, the goddess of love saw what happened and decided

to punish Narcissus. As he came to a pool of water Narcissus saw his reflection (影子) and fell in love with

the vision he saw. It was of course his own reflection.

     Poor Narcissus watched his own reflection, but every time he tried to touch the face of the vision he loved

it broke up on the shimmering surface of the water. Narcissus stopped eating, lost his beautiful looks and

desired to get his love. In the end he anguished gradually and died.

     Aphrodite took pity on him and made a flower grow in his place on the bank of the lake. Narcissus flowers

(水仙花) can be found to this day growing wherever you can find water and trees.

1. Echo fell in love with Narcissus because _____.

A. Narcissus was good-looking

B. Echo was a lively spirit

C. Narcissus loved her, too

D. Echo took pity on Narcissus

2. Why did Aphrodite, the goddess of love, punish Narcissus?

A. Aphrodite envied Echo because she loved Narcissus.

B. She thought Narcissus didn't respect and made Echo sad.

C. Narcissus fell in love with the vision, not Echo.

D. Echo was trapped in love and didn't protect trees in the forest any longer.

3. What does the underlined word "anguished" in the fourth paragraph mean?

A. Become increasingly thin and weak.

B. Become very hungry.

C. Become very fat.

D. Become out of mind. 

4. What is the main purpose of writing the passage?

A. To tell people a sad love story.

B. To tell people how Narcissus flowers came.

C. To tell the true meaning of beauty and ugliness.

D. To tell people not to affect others' love.

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《本安体系》库房的管理规定:有()记录,定期进行巡查。

A、库房巡查

B、库房检查

C、库房盘查

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