问题 问答题 简答题

取样的概念、目的和一般程序?

答案

参考答案:

(1)概念:取样是指从矿体或近矿围岩和堆积物中采集一小部分有代表性的样品用以进行各种分析、测试、鉴定与实验,以研究确定矿产质量、物化性质及开采加工技术条件的专门性工作。

(2)目的:是查明矿石和围岩的质量、矿物成分、化学成分、分带性和内部结构、技术和工艺性质的唯一有科学依据的方法。

(3)一般程序:

样品的采集→加工处理→化学分析、测试鉴定、试验等→结果的检查与评定。

阅读理解

阅读理解。

     I heard the bees long before I saw them.

     It was a very hot afternoon, and we decided to cool off in the river near my home. As we climbed

down a small rocky (石头的) hill toward the water, my boyfriend John suddenly started to shout then

jumped into the water below. Peter and Mary quickly followed but I was too far away to jump. I was

trapped.

    I heard a low hum (嗡嗡声),which was growing louder. From a distance (距离), the group of bees

looked almost like a cloud of smoke. As it got closer, I knew it was thousands of bees flying towards

me.

     All I could do was cover my face with hands. Crazily, I thought that if I sat very still, the bees would

think I was just another rock.

     After a few minutes, I  knew  my  plan  didn't work. The bees were attacking me. I  could hear my

friends shouting at me to get down to the pool fast.

     But it wasn't so easy. I was in great pain (疼痛) and the only way I could get away was to use my

hands to climb down the rocks. However, I was afraid to do that at first because  my  face would be

unprotected. The noise the bees made was so loud and frightening, but I had no way. I rushed down

the rocks and jumped into the pool, but  I don't remember doing it. I was just so  happy to  be  free

from the pain. I was safe, and the water felt wonderful.

     But we still weren't out of danger. Every  time  we  tried to  climb out  of  the pool, the bees flew

back over our heads. We spent the next three hours in the water, putting our heads under the water

from time to time to keep away the bees until they finally lost interest.

1. How many people went swimming that day?  

A. Two.    

B. Three    

C. Four    

D. Five

2. The underlined word "it" (in Paragraph 3) refers to        .

A. a rock    

B. the group of bees    

C. a hill    

D. the river

3. At first why didn't the writer want to climb down the rocks?

A. She was afraid she would fall.

B. She was too far away from pool.

C. She thought the bees would follow her.

D. She didn't want her face to be unprotected.

4. How did the writer escape (逃离) the bees?

A. She covered her face with her hands.

B. She hid behind the rocks.

C. She jumped into a water pool.

D. She pretended (假装) to be a rock.

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