问题 问答题 简答题

简述冷烧结矿筛分用的固定筛的结构及特点。

答案

参考答案:

固定筛由筛框和一组平行排列的钢制筛板构成。位置固定不动,一般筛子与水平呈35°~40°倾角,倾角可调,筛条间隙为50mm、40mm或35mm等。固定筛的优点是坚固、简单、投资少而且不用传动设备和动力。缺点是筛分效率低(60%~70%),如筛分烧结矿时在成品中夹杂有大量粉末,筛下返矿中含有一定数量大颗粒烧结矿,条筛易堵塞,设备占地面积和净空高度都大。

阅读理解

Popular music in America is what every student likes. Students carry small radios with earphones and listen to music before class, after class, and at lunch. Students with cars buy large speakers and play music loudly as they drive on the street. Adult drivers listen to music on the car radio as they drive to work. They also listen to the news about sports, the weather, and the life of American people. Most of the radio programmes are music.

Pop or popular music singers make much money. They make CDs or tapes which radio stations in many places broadcast(广播). Once the popular singer is heard all over the country, young people buy his or her tapes. Some of the money from these tapes comes to the singer. Wherever the singer goes, all the young people want to meet him or her. Now the singer has become a pop star.

There are other kinds of music that are popular among Americans. One is called folk music. It tells stories about the common life of Americans. Another is called western or country music. This was started by cowboys who would sing at night to the cows they were watching. Today, any music about country life and the love between a country boy and his girl is called western or country music.

小题1:________ kinds of music are mentioned(提到) in this passage.

A.Two

B.Four.

C.Three

D.Five小题2:When pop singers ________, they are regarded as pop stars.

A.become popular with their fans

B.make a CD or tape

C.make much money

D.are wanted to sing on the radio小题3:From the passage we know that country music is about ________.

A.the common life of Americans

B.the life of cowboys

C.the country life and love stories

D.the school life in America小题4:What would be the best title for this passage?

A.Western Music

B.Popular Music

C.History of Music

D.American Music

单项选择题