题目内容

【题目】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 / nanoelectromechanical 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 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.

1Which of the following is true of Jae Kwon?

A. He teaches chemistry at MU.

B. He is working on a nuclear energy source.

C. He developed a chemical battery.

D. He made a breakthrough in computer engineering.

2Jae Kwon gave examples in Paragraph 4_________.

A. to introduce nuclear batteries can be safely used

B. to show chemical batteries are widely applied

C. to introduce various energy sources

D. to describe a nuclear-powered system

3Liquid semiconductor is used to _________.

A. get rid of the radioactive waste

B. test the power of nuclear batteries.

C. reduce the damage to lattice structure.

D. decrease the size of nuclear batteries

【答案】

1B

2A

3C

【解析】本篇为科普短文,介绍由美国密苏里大学研究者所开发的核能电池的情况。

1B细节理解题。根据第一段的University of Missouri(MU) researchers are developing a nuclear energy source that is smaller, lighter and more efficient及第三段的叙述可知,Kwon在研究一种核能电池故选B。

2A细节理解题。根据文章第四段可知,Kwon举例的目的是为了说明核能电池是安全的。故选A。

3C细节理解题。根据倒数第二段中“part of the radiation energy can damage the lattice structure(晶体结构) of the solid semiconductor,”“By using a liquid semiconductor, we believe we can minimize that problem.”可知,通过使用液态半导体材料,可减少对晶体结构的破坏。故选C。

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【题目】Looking for a great summer read? Kid reporters from Time For Kids have reviewed the season's hottest new books. They have recommended a list of kid-approved page-turners (令人爱不释手的书) to our readers. Whether you’re fond of mysterious, fantastic or realistic fictions, there’s always one that suits you.

ThreeBirdSummer

BySaraSt.Antoine

Genre:RealisticFiction

Numberofpages:256

What’sthebasicstoryline?

Forhisentirelife,12-year-old Adam has spent summers at his grandma’s cabin in Minnesota. But this year things are different. His parents have divorced. Apart from that, Adam’s cousins won’t be vacationing at the cabin with him. Also, Grandma seems to be acting differently. At first, she’s just a bit more forgetful than usual. But after spending more time with her, Adam realizes Grandma is “slipping.”

There are new neighbors at the cabin this summer, including a girl at Adam’s age named Alice. At first, Adam isn’t interested in spending time with her. But as time goes by, their friendship flourishes(繁荣). Throughout this unusual summer, Adam searches for hidden treasure with his new friend and begins to uncover family secrets as well.

Are the characters believable?

The characters are believable because they don’t have cookie-cutter(千篇一律的) personalities. Adam is quiet and shy and finds girls difficult to understand. Alice is adventurous and unlike any girl he has ever met. Readers will likely see aspects of their personalities in the characters and recognize their friendship too.

Who would like this book?

Anyone who appreciates memories of family vacations or summertime in general will enjoy the vivid imagination that fillsThreeBirdSummer. Readers will fall into the story, almost as if they’re actually spending the summer exploring ThreeBird Lake with Adam and Alice.

1】【1While spending his summer at his grandma’s cabin this year, Adam ________.

A. became friends with his cousins

B. developed a friendship with a little girl

C. annoyed his grandma occasionally

D. played with Alice in the fields nearby

2】【2The book is likely to appeal to kids because _______.

A. it describes country life. B. it talks about school life.

C. it related to their experience. D. it is written in simple words.

3】【3The text is written to __________.

A. praise a writer for his great work.

B. discuss how to spend summer holidays.

C. encourage readers to do more reading

D. recommend a good book to readers.

【题目】Hoverboards are quite convient for people to carry or ride on the busy street, especially in college camps, more and more students choose to ride a hoverboard to class.

So hoverboards(电动滑板)were among the most popular Christmas gifts of 2015. They may have also been most dangerous gifts of 2015.

A true hoverboard looks like a skateboard without wheels. To “hover” means to float in the air without moving much in any direction. The popularity of hoverboards began in the 1980s, with the “Back to the Future” movies. Characters in the second and third films used hoverboards as transportation.

This year’s popular hoverboards, however, do not actually hover. They have wheels. And? as it turns out, they are not easy to use.

Adults and children around the world suffered hoverboard-related injuries over the weekend. Many posted pictures of the damage on social media. Twitter user David Douglas posted a pho to of both him and a young girl with the broken arms they suffered on Christmas Day. And another user Erin Rafferty uploaded a video of her mother falling off a hoverboard, with the caption, “Who let mom on the hoverboard?”

Falling is not the only risk with some hoverboards. They are also a fire risk. At one store in Texas, an employee tried to fix a hoverboard a customer brought in. The hoverboard then caught fire.

Studies suggest that some hoverboard brands have defective batteries o r plugs.

Many major airlines worldwide have banned hoverboards because of the fire risk. But some passengers did not hear the news. Australian actor Russell Crowesaid on Monday about his disappointment that Virgin Australia Airlines did not permit his children to take their hoverboards on the plane.

Major retailers (零售商)are also taking steps to improve the safety of the hoverboards they sell. Amazon in the United States now only sells hoverboards from brands that have submitted safety standard documents. The UK’s Amazon no longer sells hoverboards. It has also advised customers who bought unsafe brands of hoverboards to throw them away.

1What’s the problem with this year’s hoverboards?

A. They don’t have wheels. B. They are difficult to handle.

C. They catch fire in the sun. D. They can’t move in any direction.

2We can infer from the passage that.

A. hoverboards are still enjoying equal popularity as before.

B. hoverboards are still sold on Amazon in the United States.

C. passengers are forbidden to get on planes with hoverboards.

D. the number of hoverboard-related injuries is declining.

3The underlined word “defective” in the sixth paragraph probably means _____.

A. dead B. faulty

C. dry D. spare

4We can probably read this passage in a.

A. science fiction B. magazine

C. newspaper D. moviereview

【题目】Hey there

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Relax.You’re making the right decision.First of allyou’ll discover what interests you by taking courses in many subjects.For exampleit’s hard to decide if you want to be a painter if you’ve never painted any picturesonce you’re in a drawingroom on campusyou’ll know one way or the other.College is also a lot of fun—after you graduateyou’ll be working every weekday for 50 or so years.And remember that college graduates earn about twice the income of those who never attend college.

Finding the right college can be difficult.FortunatelyJohnson Review is here to help you every step of the way.

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For more informationcall 6003681 or visit JohnsonReview.com.Wherever you gohave a nice trip!

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Founder and CEO

Johnson Review

1The author thinks you should choose the college that is ________.

A. wellequipped B. competitive

C. suitable D. famous

2What does the author advise you to do to pay the high cost of college?

A. To ask the family for help.

B. To make a study of financial courses.

C. To do research on the price of college.

D. To get to know how to ask for financial aid.

3What’s the author’s purpose of writing this text?

A. To suggest ways to prepare for college learning.

B. To help readers find the right college.

C. To make Johnson Review popular.

D. To introduce college life.

4Where may the text be taken from?

A. A journalist book. B. A travel book.

C. A grammar book. D. An advice book.

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