Every day 25 million U.S. children ride school buses. The safety record for these buses is much better than for passenger cars; but nevertheless, about 10 children are killed each year riding on large school buses, and nearly four times that number are killed outside buses in the loading zones. By and large, however, the nation’s school children are transported to and from school safety.

  Even though the number of school bus accidents is not large, the safety of children is always of intense public concern. While everyone wants to see children transported safely, people are divided about what needs to be done--particularly whether seat belts should be compulsory.

  People in favour of seat belts on school buses--many of them parents and medical organizations--argue that seat belts are necessary not only to reduce fatality and injury, but also to teach children lessons about the importance of using them routinely in any moving vehicle. A side benefit, they point out, is that seat belts help keep children in their seats, away from the bus driver.

People who object to seat belt installation suggest that children are already well protected by the school buses that follow the National Highway Traffic Safety Administration’s (NHTSA) safety requirements set in 1977. They also believe that many children won’t wear seat belts anyway, and that may damage the belts or use them as weapons to hurt other children.

  A new Research council report on school bus safety suggest that there are alternate safety devices and procedures that may be more effective and less expensive. For example, the study committee suggested that raising seat backs four inches may have the same safety effectiveness as seat belts.

  The report sponsored by the Department of transportation at the request of Congress, reviews seat belts extensively while taking a broader look at safety in and around school buses.

1. Each year, children killed outside buses in the loading zones, are about_____.

  A. 10      B. 40      C. 30      D. 50

2. According to the passage, who has the greatest degree of control of the school buses “safety”?

  A. A new Research Council.         

B. The Department of Transportation.

  C. The Medical Organization.    

D. National Highway Traffic Safety Administration.

3. It may be inferred from this passage that_____ .

  A. many of the opponents(反对者) of seat belt installation are parents and officials of the

   Department of Transportation

  B. proposals of seat belts on school buses would be seriously considered

  C. an alternate safety device (raising seat backs four inches) may be taken into consideration

  D. The Department of Transportation may either take the idea of seat belts or other measures

  when it reviews the whole situation

4. The title below which best expresses the idea of the passage is“_____”.

  A. Making School Buses Even Safer for Children 

  B. Seat Belts Needed on School Buses

  C. Alternate Safety Devices and Procedures   

D. Safety in and around School Buses

 

Broken rubber bands and flat tires requiring replacement could soon be a thing of the past.

French researchers have developed a new kind of rubber that can repair itself when broken.The new rubber is made from widely available materials including vegetable oil and a common industrial chemical.All the materials are considered safe to the environment and can be easily reused.

The best part is that the new rubber can be repaired and used again and again without losing its strength or ability or stretch.When cut, the rubber can be made new again, simply by pressing the two broken ends back together.

The product can be repaired at room temperature, around twenty degrees Centigrade;other self-healing materials require higher temperatures for repair.

Traditionally, rubber substances are made from huge molecules(分子)connected by strong chemical links, or bonds.The new rubber is made of smaller molecules.The molecules are linked together using hydrogen bonds.When connected in this way, the molecules act like one long molecule, forming what is called supramolecular networks(超分子网).When the rubber is cut, the molecules attempt to connect with whatever molecule is near them.When pressed together, the molecules are able to repair themselves at the molecular level, making the repaired rubber like new.

However, time is an important element in the process.If the broken ends are not brought together quickly, a repair is not possible.This is because molecules will form bonds with molecules on their own side.The inventors say the surfaces of the rubber can be repaired within a week of being separated.

The rubber is the creation of scientists at the Industrial Physics and Chemistry Higher Education Institution in Paris.The organization is part of France's National Center for Scientific Research.The new material is described in greater detail in the research publication Nature

1.According to the introduction, which of the following is NOT the advantage of the new rubber?

A.It can be made as easily as common rubber.

B.It is environmentally-friendly.

C.It can repair itself at room temperature.

D.It is made of smaller molecules.

2.What does the 5th paragraph mainly tell us?

A.Why the new rubber is unique.

B.Why the new rubber can repair itself.

C.The new rubber is made from huge molecules.

D.The new rubber is different from the common rubber.

3.If we want to know more about the technology of this kind of new rubber, where can we get the information?

A.In the researchers' diary.  B.In a guide book.

C.In a research magazine.    D.In a newspaper

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