Batteries can power anything from small sensors to large systems. While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves. University of Missouri(MU) researchers are developing a nuclear energy source that is smaller, lighter and more efficient.

  “To provide enough power, we need certain methods with high energy density(密度)”,said Jae Kwon, assistant professor of electrical and computer engineering at MU. “The radioisotope(放射性同位素) battery can provide power density that is much higher than chemical batteries.”

  Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro/nanoelectromechanreal systems (M/NEMS). Although nuclear batteries can cause concerns, Kwon said they are safe.

  “People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems.”

  His new idea is not only in the battery’s size, but also in its semiconductor(半导体). Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor.

  “The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure(晶体结构) of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem.”

  Together with J. David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery. In the future, they hope to increase the battery’s power, shrink its size and try with various other materials. Kwon said that battery could be thinner than the thickness of human hair.

Which of the following is true of Jae Kwon?

A. He teaches chemistry at MU.    

B. He developed a chemical battery.

C. He is working on a nuclear energy source.

D. He made a breakthrough in computer engineering.

Jae Kwon gave examples in Paragraph 4_________.

A. to show chemical batteries are widely applied.  

B. to introduce nuclear batteries can be safely used.

C. to describe a nuclear-powered system.         

D. to introduce various energy sources.

Liquid semiconductor is used to _________.

A. get rid of the radioactive waste       

B. test the power of nuclear batteries.

C. decrease the size of nuclear batteries  

D. reduce the damage to lattice structure.

According to Jae Kwon, his nuclear battery _______.

A. uses a solid semiconductor        B. will soon replace the present ones.

C. could be extremely thin            D. has passed the final test.

The text is most probably a ________.

A. science news report        B. book review   

C. newspaper ad           D. science fiction story

Sometimes we rarely make eye contact or make small talk with the people who are just beside or around you, so we act sometimes as if they don’t exist.

Here is an example. At nine most mornings the same scene is repeated in office buildings around the world. An employee walks into the elevator with his boss and apart from a mumbled “good morning” the junior is lost for other words. “That’s an opportunity missed”, says experts, who believe that such an obviously dull 30 – second conversation can be invaluable for those who want to climb the career ladder.

“Small talk can help build relationship on which you can build,” says Dusseldorf communication advisor Thorsten Knobble, whose company customizes curriculum vitae(个人简历) and job references.

As a matter of fact, the importance of small talk goes far beyond the relationship to one’s boss. People who fail the art of speaking a lot without actually saying anything find it harder to cultivate relationships in the workplace, believes Levy, director of the senior management association.

“Small talk is an essential part of networking,” he says.

Virtually every conversation begins and ends with small talk, according to Wolf Lasko, who has written a book on the topic and its bearing on career prospects.

Not everyone is good at small talk. It takes skill to pick the right moment and the right topic with which to start a conversation. There are plenty of topics although some are not suitable for informal chat. “Anything to do with sex is taboo,” cautions Knobble. “Care is needed with politics, religion, money, health or personal feelings or lives.” Safe topics include weather, holidays, movies, jobs, sports or past experiences.

Which of the following might be the best title for the text?

    A. Small Talk Difficult to Start    B. Small Talk and Safe Topics

    C. Small Talk Easy Or Not   D. Small Talk Essential to Your Career 

Small talk can do all the following except that _________.

    A. it can be an important part of the Internet

    B. it can make you successful in your career

    C. it can help you get along with the people you work with

    D. it can be an opportunity to start your relationship with your boss

Which of the following is True according to the passage?

    A. Try to avoid the embarrassing time of meeting your boss.

    B. Small talk takes place every morning at nine in office buildings.

    C. All the people can start a conversation with the right topic at the right moment.

    D. Everyone is not skilled at small talk.

What word do you think can replace the underlined word “taboo”?

    A. allowed         B. attracted          C. forbidden        D. discussed

Smoking, which may be a pleasure for some people, is a series of discomfort for their fellows. Medical scientists have expressed their concern about effect of smoking on the health not only of those who smoke but also those who do not smoke. In fact, non-smokers who take in the air polluted by tobacco smoke suffer more than the smokers themselves. A great number of students are trying to persuade the university to forbid smoking in classrooms. Believe they are completely right in their aim. However, I think it more important to achieve this by calling on the smokers to use good judgment and to show concern for others. Smoking is not allowed in theaters, cinemas and in other public places. Therefore, smoking must be forbidden in our classroom. Although many people have passed away for having smoked a lot and we call on people to give up smoking, yet many more that are following will turn down what we say every day, above all, the young people smoke a lot more.

In the writer’s opinion, smoking does good to ________.

A. nobody B. some people C. smokers D. young people

The phrase “pass away” probably means ________.

A. leave one’s home B. lose one’s life C. pass by D. go away

According to the selection, which of the following is true?

A. Smokers suffer from the polluted air more than the non-smokers.

B. Non-smokers suffer from the polluted air more than the smokers.

  C. Non-smokers suffer as much from the polluted air as the smokers.

D. Non-smokers don’t suffer so much from the polluted air as the smokers.

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