题目内容

When coal is burned in a boiler, two kinds of ash by-products are produced: a heavy bottom ash and a fine-as-powder fly ash. About 10 to 15 percent of the coal by-product is bottom ash which is used like sand on streets and highways covered with ice, and also on highways as paving material.

It is the fly ash, however, that is receiving much attention. Once considered a waste, fly ash is now regarded as a natural resource in the United States. It can be placed in some lower places, where it is compacted and covered with soil, for the seeds of various grasses and plants to be placed in the soil to make the land productive.

Fly ash may be added to concrete to build roads and other kinds of buildings, taking the place of the cement up to 20 percent. As a by-product of burned coal, fly ash requires no extra energy to be produced, while cement production requires great amounts of energy.

Besides, the technology is able to take out some useful minerals from the fly ash, which is still a very expensive process today. But the time may come when it is cheaper to take out these products from ash than to mine new supplies.

The bottom ash can be put on icy streets________.

       A. in order to rebuild them          B.  in order to make them colourful

       C. so that people can walk on them   D. so that cars can run faster

The fly ash_______ bottom ash.

       A. has the same use as             B.  is more expensive than

       C. has more uses than    D. is much cheaper than

The fly ash can be used to________.

       A. grow various plants   B.  take the place of soil

       C. cover productive land       D. make more productive land

Which of the following is right?

       A. To produce fly ash, some extra coal is to be burned.

       B.  Fly ash is made while producing cement.

       C. It takes less energy to produce fly ash than cement.

       D. Fly ash is a costless by-product.

The word “mine” in the last sentence of the passage means_______.

       A. to buy things from other countries

       B.  to search for useful materials in the mountains

       C. to dig deeply into the ground to get useful materials

       D. to take out certain materials from other things

【小题1】C【小题2】C【小题3】D【小题4】D【小题5】C


解析:

略

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Each year, road accidents kill a million people and injure millions more . The economic costs are greatest for developing countries . Earlier this year , the United Nations called for a campaign to improve road safety .

     One way to avoid accidents is better driving . Another is better roads and bridges . Engineers in the Unites States have designed ten new concrete mixtures that they think could make bridges last longer .

     Professor Paul Tikalsky leads the experiments by a team at Pennsylvania State University . He says bridges made of concrete now last about twenty-five to thirty-five years . But he says the new mixtures might extend that to seventy –five or even one-hundred years .

     Concrete is made of stone , sand , water and cement(水泥). The materials in the cement hold the concrete together . Ancient Romans built with concrete . Yet strengthened concrete bridges did not appear until the late 1800s . People keep looking for new ways to improve concrete . Professor Tikalsky says it is one of the most complex of all chemical systems .

     The new mixtures designed by his team contain industrial waste products . He says these make the concrete better able to resist damage from water and salt over time . One of the products is fly ash . This is released into the air as pollution when coal is burned .

     Professor Tikalsky says particles (颗粒)of fly ash are almost exactly the same size and chemical structure as Portland cement . This is the most costly material in concrete . So using fly ash to replace some of it would save money .

     The federal government is paying for part of the research . Engineers anywhere can use the technology . Professor Tikalsky says some of the ideas have already been put to use in China , the Philippines and other countries .

Why did the United Nations launch the campaign ?

  A. Because the United Nations wanted to reduce road accidents and economic costs

  B. Because two million people were killed in the accidents .

  C. Because engineers wanted to design ten new concrete mixtures .

  D. Because the United Nations made bridges of the new mixtures which could last for about 20 to 35

   years .

What does the underlined word “ this ” in the sixth paragraph refer to ?

  A. Fly ash      B. Portland cement      C. Sand       D. Chemical

Which of the following statements is TRUE ?

  A. Ten new concrete bridges have already been built in the United States .

  B. A new concrete bridge could last 50 more years than an ordinary concrete one .

  C. People didn’t know how to build with cement until the late 1800s .

  D. Water and salt won’t do any damage to bridges over time .

What does the passage mainly tell us ?

  A. The causes of road accidents .             B. The advantages of fly ash

  C. The measures of avoiding road accidents    D. Latest information about long-life concrete bridges

With the average temperature for January standing at －50 ℃，it is no wonder the Russian village of Oymyakon is the coldest permanently inhabited settlement in the world.Known as the“Pole of Cold”，the coldest ever temperature recorded in Oymyakon is －71.2 ℃.This is the lowest recorded temperature for any permanently inhabited location on Earth and the lowest temperature recorded in the northern hemisphere(北半球)．

Ironically，Oymyakon actually means“non?freezing water”due to a nearby hot spring.Most homes in Oymyakon still burn coal and wood for heat and enjoy few modern conveniences.

Nothing grows there so people eat reindeer(驯鹿)meat and horsemeat.A single shop provides the town's bare necessities and the locals work as reindeer?breeders，hunters and ice?fishermen.

There are few modern conveniences in the village—with many buildings still having outdoor toilets—and most people still burn coal and wood for heat.When coal deliveries are irregular，the power station starts burning wood.If the power ceases，the town shuts down in about five hours，and the pipes freeze and crack.

Daily problems that come with living in Oymyakon include pen ink freezing，glasses freezing to people's faces and batteries losing power.Locals are said to leave their cars running all day for fear of not being able to restart them.Even if there was coverage for mobile phone reception，the phones themselves would not work in such conditions.

Another problem caused by the frozen temperatures is burying dead bodies，which can take anything up to three days.The earth must first have thawed(融解)sufficiently in order to dig it，so a bonfire is lit for a couple of hours.Hot coals are then pushed to the side and a hole couple of inches deep is dug.The process is repeated for several days until the hole is deep enough to bury the coffin.

Travel companies offer tourists the opportunity to visit the village and sample life in the freezing conditions.

1.From the passage we can infer that people in Oymyakon ________.

A．prefer meat to any other kind of food

B．seldom have fresh vegetables and fruits

C．can buy anything in the shop

D．might row a boat to catch fish

2.Which of the following is the first step when burying a dead body?

A．The coffin must be put in place.

B．A bonfire has to be lit first.

C．Hot coals have to be pushed to the side.

D．A hole couple of inches deep is dug.

3.Mobile phones would not work in Oymyakon because ________.

A．the batteries are of poor quality

B．there was no coverage for phone reception

C．batteries can't be charged in such conditions

D．the extreme coldness makes the batteries lose power

4.Why do the locals have their cars running all day?

A．They are afraid they can't get the car started.

B．They want to keep warm in the car.

C．They have abundant oil resources.

D．They have little awareness of saving.

 

.

When coal is burned in a boiler, two kinds of ash by-products are produced: a heavy bottom ash and a fine-as-powder fly ash. About 10 to 15 percent of the coal by-product is bottom ash which is used like sand on streets and highways covered with ice, and also on highways as paving material.

It is the fly ash, however, that is receiving much attention. Once considered a waste, fly ash is now regarded as a natural resource in the United States. It can be placed in some lower places, where it is compacted（压实） and covered with soil, for the seeds of various grasses and plants to be placed in the soil to make the land productive.

Fly ash may be added to concrete (混凝土）to build roads and other kinds of buildings, taking the place of the cement(水泥) up to 20 percent. As a by-product of burned coal, fly ash requires no extra energy to be produced, while cement production requires great amounts of energy.

Besides, the technology is able to take out some useful minerals from the fly ash, which is still a very expensive process today. But the time may come when it is cheaper to take out these products from ash than to mine new supplies.

49. The bottom ash can be put on icy streets________.

A. in order to rebuild them          B. in order to make them colorful

C. so that people can walk on them   D. so that cars can run faster

50. The fly ash can be used to________.

A. grow various plants   B. take the place of soil

C. cover productive land       D. make more productive land

51. Which of the following is right?

A. To produce fly ash, some extra coal is to be burned.

B. Fly ash is made while producing cement.

C. It takes less energy to produce fly ash than cement.

D. Fly ash is a costless by-product.

52. The word “mine” in the last sentence of the passage means_______.

A. to buy things from other countries

B. to search for useful materials in the mountains

C. to dig deeply into the ground to get useful materials

D. to take out certain materials from other things

 

When coal is burned in a boiler, two kinds of ash by-products are produced: a heavy bottom ash and a fine-as-powder fly ash. About 10 to 15 percent of the coal by-product is bottom ash which is used like sand on streets and highways covered with ice, and also on highways as paving material.

It is the fly ash, however, that is receiving much attention. Once considered a waste, fly ash is now regarded as a natural resource in the United States. It can be placed in some lower places, where it is compacted and covered with soil, for the seeds of various grasses and plants to be placed in the soil to make the land productive.

Fly ash may be added to concrete to build roads and other kinds of buildings, taking the place of the cement up to 20 percent. As a by-product of burned coal, fly ash requires no extra energy to be produced, while cement production requires great amounts of energy.

Besides, the technology is able to take out some useful minerals from the fly ash, which is still a very expensive process today. But the time may come when it is cheaper to take out these products from ash than to mine new supplies.

1. The bottom ash can be put on icy streets________.

A．in order to rebuild them

B． in order to make them colourful

C．so that people can walk on them

D．so that cars can run faster

2.The fly ash_______ bottom ash.

A．has the same use as

B． is more expensive than

C．has more uses than

D．is much cheaper than

3.The fly ash can be used to________.

A．grow various plants

B． take the place of soil

C．cover productive land

D．make more productive land

4. Which of the following is right?

A．To produce fly ash, some extra coal is to be burned.

B． Fly ash is made while producing cement.

C．It takes less energy to produce fly ash than cement.

D．Fly ash is a costless by-product.

5.The word “mine” in the last sentence of the passage means_______.

A．to buy things from other countries

B． to search for useful materials in the mountains

C．to dig deeply into the ground to get useful materials

D．to take out certain materials from other things

 

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