由一种固体金属在恒温条件下,同时生成两种不同化学成分的新固相,这种转变称为()转变。

题型:单项选择题

问题:

由一种固体金属在恒温条件下,同时生成两种不同化学成分的新固相,这种转变称为()转变。

A、共晶

B、共析

C、包晶

D、化合物分解

考点:热处理工考试热处理工考试题库
题型:单项选择题

需要证单名称:按需要检验检疫机构出具的证单,在对应的窗口打(),并应注明所需证单的正副本的数量。

A.*

B.×

C.√

D.以上都不对

题型:单项选择题

下列物质互为同分异构体的是(  )

A.2,2­二甲基丙烷和新戊烷

B.间二甲苯和1,3­二甲苯

C.2­甲基­1­丁烯和3­甲基­1­丁炔

D.1­丁醇和2­丁醇

题型:单项选择题

阅读理解。

     People constantly focus on wealth and winning as the most important parts of life. But we shouldn't forget

that life is too short not to live a little.

     At high school, the pressure of trying to get excellent grades can be very great. Sometimes it seems like I

live at school! When I am home all my time is spent doing homework in my room.

     I have a younger sister. We used to see a lot of each other, but after I graduated from the school she

attends, I see less and less of her.

     Then one day I came home to an empty house and found a note from my mom saying that my sister was

at her friend's and would be dropped off (送回).

     At five o'clock I saw my sister walking toward the door with her friend and her friend's father. I heard

them talking.

      "Is anyone home?" the father asked.

      "Just my mean big sister, and she's probably in her room as always,"my sister replied. I couldn't believe it.

I opened the door, thanked the father for bringing her home, shut the door and started to cry.

     A huge fight followed and it ended with me driving my sister to her room. When my mom got home, I told

her what had happened, and I realized what was worse than the fight was that I really hadn't been a good big

sister… I had lost track of what was important, what really mattered.

      I had fallen into a whirlpool of competition, and it took my sister's honest observation to show me that the

grades I got didn't matter to everyone-certainly not to her. All that matters to her is that I'm her big sister, and

that's what matters to me, too.

1. The underlined sentence in the first paragraph probably advised us _____.

A. to work hard and be successful

B. to enjoy the pleasure of life

C. to take our time in daily life

D. to live like rich people

2. What kind of life did the author live at high school?

A. Happy and active.

B. Peaceful and comfortable.

C. Busy and competitive.

D. Wild and empty.

3. Why did the author's sister consider her as a mean sister?

A. Because she didn't take her sister home after school.

B. Because she didn 't do well in her schoolwork.

C. Because she always fought with her sister at home.

D. Because she didn't care more about her sister.

4. What lesson did the author learn from her experience?

A. It is love rather than grades that matters in life.

B. Winning at school can win you respect from others.

C. One shouldn ' t compete with one ' s sister for parents' love.

D. There is no end in looking for what really matters.

题型:单项选择题

增加小麦出粉率,何种营养素的损失尤为明显()

A.碳水化合物

B.脂肪

C.水分

D.无机盐

E.B族维生素

题型:单项选择题

气质类型一定程度上会影响我们品德的好坏和成就。

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