问题 问答题 简答题

影响煤变质的因素有哪些?他们对煤的变质作用产生哪些影响?

答案

参考答案:

影响煤变质的因素有:温度、压力和时间。

(1)温度:温度是影响煤变质的主要因素。地温增高,煤化程度增高。

(2)压力:压力也是引起煤变质的因素之一。由于上覆岩层沉积厚度不断增大,使地下的岩层、煤层受到很大的静压力,导致煤和岩石的体积收缩,在体积收缩的过程中,发生内摩擦而放出热量,使地温升高,间接地促进煤的变质。此外在地壳运动的过程中,还会产生一定方向的构造应力,在构造应力的作用下,形成断裂构造,断裂两侧岩块相对位移时,放出热量,也可引起煤变质。

(3)时间:时间是影响煤变质的另一重要因素。在温度、压力大致相同的条件下,煤化程度取决于受热时间的长短,受热时间越长,煤化程度越高,受热时间短,煤化程度低。

阅读理解

阅读理解

                                                        Crossing the Rubicon

     The march to Italy was began.The soldiers were even more enthusiastic than Caesar (恺撒) himself.

They climbed mountains,  waded rivers,  endured tiredness,  and faced all kinds of danger for the sake

of their great leader.

     At last they came to a little river called the Rubicon (卢比孔河). It was the boundary line of Caesar's

Province of Gaul;  on the other side of it was Italy.Caesar paused a moment on the bank.He knew that

to cross it would be to declare war against Pompey and the Roman Senate;  it would involve all Rome in

a fearful battle,  the end of which no man could foresee.

     But he did not hesitate long.He gave the word,  and rode boldly across the shallow stream.

     "We have crossed the Rubicon,  " he cried as he reached the farther shore."There is now no turning

back." Soon the news was carried to Rome "Caesar has crossed the Rubicon" and there was great fear

among those who had planned to destroy him.Pompey's soldiers deserted him and hurried to join

themselves to Caesar's army.The Rome senators and their friends made ready to escape from the city.

     "Caesar has crossed the Rubicon!" was shouted along the roads and byways leading to Rome;  and

the country people turned out to meet and hail with joy the conquering hero.

     The word was carried a second time to the city "Caesar has crossed the Rubicon" and the wild fight

began.Senators and public officers left everything behind and hurried away to seek safety with Pompey.

On foot,  on horseback,  in litters,  in carriages,  they fled for their lives-all because Caesar had crossed

the Rubicon.Pompey was unable to protect them.He hurried to the seacoast,  and,  with all who were

able to accompany him,  sailed away to Greece.

     Caesar was the master of Rome.

1. Which of the following can NOT be used to describe Caesar's army?

A. Enthusiastic in the march.

B. Not afraid of tiredness.

C. Brave in the march.

D. Eager to be great leaders.

2.  According to the passage,  crossing the Rubicon meant all of the following EXCEPT that______.

A. Caesar declared war against Pompey and the Roman Senate

B. Caesar would involve all Rome in the battle

C. Caesar would be defeated in the war

D. Caesar was determined to carry out the battle

3. What happened when the news was first carried to Rome that Caesar had crossed the Rubicon?

A. The people who had been against Caesar felt very frightened.

B. The people who had turned traitor to Caesar were wild with joy.

C. The public officers and soldiers fought bravely against Caesar.

D. The Rome senators and their friends had already escaped.

4. What did Pompey do after Caesar crossed the Rubicon?

A. He rode to the bank of the Rubicon hurriedly.

B. He fled to Greece by sea with all his companions.

C. He had all his relatives and soldiers stay with him.

D. He kept calm and stayed in Rome,  defeating his enemies.

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