问题 问答题 简答题

采用充填采矿法开采时,充填井的位置选择应符合那些条件?

答案

参考答案:

(1)布置在矿体中央位置;若矿体分布范围大或有几个矿体,则按区域或按矿体布置几个充填井,务使充填料到运输功最小;

(2)由采石场(或尾矿库)至充填井再达所辖充填采空区或采场,构成顺向运输,尽量减小充填料的运输功;

(3)地面地形条件应对运送充填料有利;

(4)直接借充填料重力溜放的废石井或借水力运输砂石、尾砂的充填钻孔,要求其所通过的岩层坚硬、稳固、无裂隙,工程地质条件良好;

(5)地下各阶段间转运充填料的充填井,可利用岩层整体性好、耐磨性强调探矿天井;

(6)各采空区或采场的充填井,一般靠近其中央位置。

阅读理解

阅读理解。

     It's easy to see how to help others, but what about those whose needs aren't so obvious? This story

may have happened a while back, but it was a lesson which has stayed with me and helped me ever since.

It was Thanksgiving and I was volunteering with my parents at a shelter for the poor. We stood behind

the counter dishing out hot food to whoever came in. most of our dinners looked like they had been

having hard times, their clothes old, worn and dry. In short, they looked poor!

     Then, a man came in, who looked anything but poor. He was well dressed, wearing an expensive suit.

I wondered what he was doing there and my jaw dropped in amazement when he joined the line for food. The closer he came to my service station, the more I muttered. What was this man doing? I wanted to

know. Surely he wasn't gong to take food.

     Then my mother quietly took me to one side. She said, "You have assumed that the needs of the

people who come here must be purely physical: hunger, inadequate shelter and needs are emotional?

What if he needs comfort, friends, or just to be among other human beings?" her words hit me like a ton

of bricks! I felt like I should apologize to the man, but I didn't.

     About a week later the shelter received a large donation from an anonymous source. I can't help but

wonder if it came from that man.

     Now, whether I meet others, I remember my mother's words and try to send kindness and blessings

to them, regardless of how they look.

     Needs aren't always visible. But kindness always makes a difference.

1. The task of the author at the shelter was to_______.

A. decide whether dinners looked poor      

B. learn life experience there

C. serve hot food to the poor                

D. help parents order dishes

2. When the man waited in line, how did the author feel?

A. Surprised        

B. Pitiful            

C. Excited      

D. Angry

3. The author felt he should apologize to the man, because he_______.

A. was asked to do so by his mother  

B. gave the man food much less than others

C. realized something was wrong with the man

D. knew later that the man went there to donate

4. What can we infer from the last paragraph?

A. We should show others kindness whatever their needs are  

B. Some needs can't be known clearly at times

C. Needs can always be met by kindness

D. We should find out others' needs 

单项选择题