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 (半導體). 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 (晶體結構) of the solid semiconductor," Kwon said, "By using a liquid semicon
ductor, 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.
優等生題庫系列答案科目：高中英語 來源：黑龍江省2010屆高三下學期第四次模擬考試試題（英語） 題型：閱讀理解
第三部分 閱讀理解 (共20小題；每小題2分，滿分40分)
第一節 (共15小題；每小題2分，滿分30分)
閱讀下列短文，從每題所給的四個選項（A、B、C和D）中，選出最佳選項，并在答題卡上將該項涂黑。
When I was at university, I studied very hard. But a lot of my friends did very little work. Some did just enough to pass exams. Others didn't do quite enough. Fred Baines was one of them. He spent more time drinking in the Students' Union than working in the library.
Once, at the end of the term, we had to take an important test in chemistry. The test had a hundred questions. Beside each question, we had to write "True" or "False". While I was studying in my room the night before the test, Fred was watching television. Fred usually worried a lot the night before a test. But on that night he looked perfectly calm. Then he told me of his plan.
"It's very simple. There are a hundred questions and I have to get fifty correct to pass the test. I'll take a coin into the examination room. I haven't studied a chemistry book for months, so I'll just toss the coin. That way, I'm sure I'll get half the questions right."
The next day Fred came cheerfully into the examination room. He sat tossing a coin for half an hour as he marked down his answers. Then he left, half an hour before the rest of us.
The next day, he saw the chemistry professor in the corridor .
"Oh, good," he said. "Have you got the result of the test? What mark did I get?"
The professor looked at him and smiled.
"Ah, it's you, Baines. Just a minute."
Then he reached into his pocket and took out a coin. He threw it into the air, caught it in his hand and looked at it.
"I'm terribly sorry, Baines," he said, "you failed."
1. Fred Baines _______.
A. spent quite some time working in the Students' Union
B. worked hard at his lessons but he failed again and again
C. often failed his tests
D. wouldn't work hard so long as he could pass a test
2 Fred looked perfectly calm before the chemistry test because _______.
A. he was already well prepared for it
B. he didn't think the test was so important for him
C. someone had promised to help him out
D. he believed he had found out a way to pass the test without any difficulty
3. The professor told Baines the result of the test by tossing a coin because _______.
A. he hadn't marked all the papers yet
B. he couldn't remember the mark Baines got
C. he wouldn't hurt Baines' feeling by telling him the truth
D. he wanted to teach Baines a lesson
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科目：高中英語 來源：湖南省2010屆高三下學期第二次模擬考試英語試卷 題型：閱讀理解
第三部分 閱讀技能 (共三節，滿分35分)
閱讀理解 （共12小題；每小題2分，滿分24分）
閱讀下列短文，從每題所給的A、B、C、D四個選項中，選出最佳選項，并在答題卡上將該項涂黑。
I am an e-mail user. When I first started to use the e-mail system, I used to read all my e-mail. I didn’t have much mail. I gave my friends my e-mail address. Soon I had more mail than I wanted. Some of the mail was junk mail. I was worried. I didn’t want my mail to control me.
I’ve tried some methods to help me get control of my mail. First, I check my mail at the same time every day. Also I try to allow myself only 15-20 minutes every day to process my e-mail. This doesn’t always work, but I try. Sometimes I save the messages. Sometimes I just read them, maybe answer a few, and then delete（刪除）them.
Sometimes I’m not at all interested in a message, so I don’t even open it. I delete it right away. This is very much the way I go through the mail that the postal service delivers to my home.
These methods are very simple. I have some friends who are very clever with computers. From time to time, they teach me new tricks for managing my e-mail. I’m still amazed at what e-mail can do for me! I’m still worried, however, about having too much to read.
1. The writer used to read all his e-mail because _______.
A. he didn’t have much mail B. he had nothing else to do
C. he didn’t know how to read mail D. he was forced to do that
2. Which of the following does NOT belong to the ways of the writer’s dealing with his mail?
A. Saving the messages. B. Just reading some.
C. Deleting some. D. Passing some on to friends.
3. What does the underlined word “they” in the last paragraph refer to?
A. messages B. friends C. computers D. methods
4. What’s the purpose of the writer to write this passage?
A. To share happiness in using mail with us.
B. To share some worries in using mail with us.
C. To share some methods of using computer with us.
D. To persuade us out of using mail.
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科目：高中英語 來源：湖南省20092010學年度高一下學期期末考試試卷（英語） 題型：閱讀理解
第三部分閱讀技能 (共三節，滿分35分)
閱讀理解（共12小題；每小題1.5分，滿分18分）
閱讀下列短文，從每題所給的A、B、C、D四個選項中，選出最佳選項，并在答題卡上將該項涂黑。
TEENAGERS lead an exciting life in high school, making friends and dreaming about the future. However, as all young people know, teenagers have plenty of worries too.
Do you know what British teenagers worry about most? A survey by the UK's Department of Health shows that the top worries are losing weight (減肥) and fitting in (適應). Over 100,000 teenagers took part in the research.
Losing weight is a big concern among teenagers. This may be an effect of famous people with perfect bodies around them.
Adolescence is a physically and emotionally difficult time. Teenagers want to feel good about their bodies.
It's also important for them to be accepted. Many teenagers were picked on (作弄) in high school. “Who should I eat lunch with?” “Who should I hang out with?” “Will I be accepted?” These questions are troubling many UK teenagers, according to the survey.
It's interesting to see that family background has an effect on teenagers' worries. Teenagers from low-income families worried more about losing weight and bullying (欺凌弱小). Teenagers from higher income families were more likely to worry about fitting in and peer pressure (同輩壓力).
49 According to the survey, British teenagers are most worried about ______.
A. fitting in and making money B. finding jobs and making friends
C. losing weight and being accepted D. making money and losing weight.
50. Many teenagers are concerned about losing weight because ______.
A. they see thin famous people B. they care a lot about health
C. they don't have much money D. they face problems in life
51. The word “adolescence” in the fourth paragraph means ______.
A.幼兒期 B.青春期 C.青年期 D.老年期
52. Suppose Jack is from a poor family; what do you think he may worry more about?
A. fitting in and losing weight B. fitting in and peer pressure
C. losing weight and bullying D. losing weight and peer pressure
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科目：高中英語 來源：河南商丘市2010年高三第三次模擬考試英語試題 題型：閱讀理解
第三部分 閱讀理解（共20小題；每小題2分，滿分40分）
閱讀下列短文，從每題所給的四個選項（A、B、C和D）中，選出最佳選項，并在答題卡上將該項涂黑。
A new study suggests that the more teenagers watch television, the more likely they are to develop depression （沮喪；抑郁）as young adults.
The researchers used a national long - term survey of adolescent health to investigate（調查）the relationship between media use and depression. They based their findings on more than four thousand adolescents who were not depressed when the survey began in 2000.
As part of the survey, the young people were asked how many hours of television or videos they watched daily. They were also asked how often they played computer games and listened to the radio. Media use totaled an average of five and one - half hours a day. More than two hours of that was spent watching TV.
Seven years later, in 2007, more than seven percent of the young people had signs of depression. The average age at that time was twenty -one.
The study didn’t explore if watching TV causes depression. But one possibility is that it was taking time away from activities that could help prevent depression.
Previous study found that people who describe themselves as happy spend less time watching television than unhappy people. The study found that happy people are more likely to be socially active to read, to attend religious services and to vote.
1. The result of the research seems to prove ________.
A. teenagers are more likely to develop depression than adults
B. other media uses do no harm to adolescents
C. TV probably causes teenagers to grow up with depression
D. those who don’t watch TV will not develop depression
2. We can learn from the survey that of all the media use ________.
A. computer games are teenagers’ favorite
B. most teenagers prefer to listen to the radio
C. teenagers enjoy watching TV very much
D. newspaper is not included in the survey
3. According to the passage, what kind of activity may help prevent depression?
A. Playing computer games. B. Taking part in sports.
C. Listening to the radio. D. Watching movies.
4. We can conclude that a teenager should ________.
A. play more video games instead of watching TV
B. be active in taking part in outdoor activities
C. be more active in watching educational TV programmes
D. attend religious services and care for politics
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科目：高中英語 來源：江蘇省2010屆高三考前模擬訓練英語試卷 題型：閱讀理解
第三部分 閱讀理解（共15小題，每小題2分，滿分30分）
請認真閱讀下列短文，從短文后各題所給的A，B，C，D 四個選項中，選出最佳選項，并在答題卡上將該項涂黑。
Britons stranded（擱淺）at sea or in flooded homes could find a real-life prince riding to their rescue. Prince William announced on Monday that he is to train to be a full-time pilot with the Royal Air Force's Search and Rescue Force (SARF).
William, who is currently a Lieutenant（中尉）in the Army's Household Cavalry Regiment（皇家騎兵團）, will transfer to the RAF and begin an 18-month training course in January 2009.
If successful, he will become a fully operational Search and Rescue pilot in 2010, flying Sea King helicopters at one of the six SARF units based in Britain.
"The time I spent with the RAF earlier this year made me realize how much I love flying," the prince, who spent two weeks with a SARF team while on work experience in 2005, said in a statement.
"Joining Search and Rescue is a perfect opportunity for me to serve in the Forces operationally, while contributing to a vital part of the country's Emergency Services."
It means he will follow a similar career to that of his uncle, Prince Andrew, who was a Sea King helicopter pilot during the 1982 Falklands war.
The Search and Rescue teams' main duty is to recover RAF personnel but in peacetime they mainly respond to civilian emergencies, dealing with more than 1,000 calls a year.
The units deal with incidents ranging from helping those trapped by sudden major floods to rescuing people lost while out walking on hills
William, who has spent the last year on secondment（借調）to the various branches of the military to prepare for his future role as head of the armed forces, received his RAF wings （飛行勛章）following a four-month stint（持續的工作）with the service earlier this year.
However, his time with the RAF was clouded when the Defense Ministry was forced to fend off (擋開) criticism for allowing the prince to fly military helicopters to a bachelor party for his cousin and to the family home of his girlfriend Kate Middleton.
1. Prince William wanted to be a full-time pilot because _______.
A. he liked flying
B. he would like to do something in the country’s Emergency Services
C. many Britons were in danger at sea waiting for rescue
D. he had much experience in flying
2 According to the passage, _______
A. the Falklands war broke out in 2005
B. Prince William served in the Army’s Household Cavalry Regiment in 1982
C. Prince Andrew is serving in SARF now
D. William would finish his training course in June 2010
3 The author’s opinion on William’s joining RAF is _______.
A. enthusiastic B. doubtful C. negative D. pessimistic
4. What is the purpose of the author by mentioning what the prince had done before in the last
paragraph?
A. The author wants to say that Prince William pays much attention to his family and friends
B. The author suggests that the Defense Ministry was criticized when William flew for his
private business
C. William had a hard time when he went against his leaders
D.The author has the worry that Prince William is likely to get the Defense Ministry into
trouble again.
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