Batteries can power anything from small sensors to large systems. While scientis

Batteries can power anything from small sensors to large systems. While scientis

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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(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.
1. 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.
2. 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.
3. 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.
4. 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.
5. The text is most probably a ________.
A. science news report        B. book review   
C. newspaper ad              D. science fiction story
答案

小题1:C
小题2:B
小题3:D
小题4:C
小题5:A
解析

举一反三

第二部分 阅读理解  (满分35分)
第一节 语篇阅读 (每小题2分)
阅读理解下面的短文,然后根据短文内容,指出能完成所给句子或回答所提问题的最佳答案。
Astronomy (天文学) is the oldest science known to man. Thousands of years ago man looked at the stars and wondered about heavens (天堂). But the six planets that he could see with his eyes alone limited man.
The Greeks studied astronomy over 2,000 years ago. They could see the size, color, and brightness of a star. They could see its place in the sky. They watched the stars move as the seasons changed. But the Greeks had no tools to help themselves study the heavens.
Each new tool added to the field of astronomy helped man reach out into space. Until there were telescopes (望远镜), man did not know much about the moon. He did not know that the planet called Saturn (土星) had rings around it. His sight was so limited that he could not see all the planets. In the early 1700s, people thought there were only six planets. Pluto (冥王星), the last of the nine planets to be discovered was seen until 1930.
Before the spectroscopes (分光镜), man didn’t know what kind of gas was in the sun or other stars, without radio telescopes (射电望远镜), we did not know that radio noise came from far in space.
Today, astronomy is a growing science. We have learned more in the past fifty years than in the whole history of astronomy.
1Thousands of years ago, man watched ____ with his eyes.
A. the moon       B. the stars         C. the universe    D. all the planets
2 When the Greeks watched the stars, they could ____ .
A. know what the stars were made of     B. not see their places in the sky
C. help themselves study the heavens     D. watch the stars move as the seasons changed
3Until there were ____ , man knew very little about the moon.
A. telescopes      B. spectroscopes C. radio telescopes   D. spaceships
3People didn’t know about Pluto until ____ .
A. the 1700s      B. 2,000 years ago   C. 1930             D. thousands of years ago
5____ people began to do research on astronomy.
A. 50 years ago  B. 90 years ago  C. In the early 1700s      D. Over 2,000 years ago
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第三节 完形填空(每小题1分)
阅读下面短文,从短文后各题所给的四个选项中,选出可以填入空白处的最佳选项。
Scientists find that hard-working people live longer than average men and women. Career women are  1  than housewives. Evidence (证据) shows that  2  are in poorer health than the job-holders. A study shows that whenever the unemployment (失业) rate increases by 1%,the death rate increases correspondingly (相应地) by 2%. All this comes down to one point: Work is helpful to heath.
Why is work good for health? It is because work keeps people busy, _3  loneliness and solitude (孤独). Researches show that people feel unhappy,  4  and lonely when they have nothing to do. Instead, the happiest are those who are  5 . Many high achievers who love their careers feel that they are the happiest when they are working hard. Work serves as a  6  between man and reality (真实). By work, people come into contact with each other. By collective (集体的) activity, they find friendship and warmth. This is helpful to health. The loss of work  7_ the loss of everything. It affects man spiritually (在精神上) and makes him liable to (易于)  8 .
9 , work gives one a sense of fulfillment (充实感) and a sense of  10 . Work makes one feel his value and status in society. When a  11  finishes his writing or a doctor successfully operates on a patient or a teacher sees his students grow, they are  12  beyond words (无法用语言表达).
From the above we can come to the conclusion  13  the more you work,  14  you will be. Let us work hard,  15  and live a happy and healthy life.
⒈ A. more healthier        B. healthier      C. weaker         D. worse
⒉ A. career women         B. the busy       C. the jobless   D. the hard-working
⒊ A. up with   B. off         C. in touch with        D. away from
⒋ A. interested       B. joyful    C. concerned   D. worried
⒌ A. busy         B. free      C. lazy      D. empty
⒍ A. river         B. gap       C. channel        D. bridge
⒎ A. means     B. stands C. equals D. matches
⒏ A. success   B. death   C. victory D. disease
⒐ A. Besides   B. Nevertheless       C. However      D. Yet
⒑ A. disappointment      B. achievement        C. regret  D. apology
⒒ A. worker    B. farmer C. writer  D. manager
⒓ A. moved     B. surprised     C. sad       D. happy
⒔ A. that         B. which   C. what    D. when
⒕ A. the lonelier and weaker B. lonelier and healthier
C. happier and healthier D. the happier and healthier
⒖ A. study well        B. studying well        C. study good  D. studying good
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第二部分:阅读理解(共20 小题。第一节共15 小题,每题2分;第二节共5 题,每题2分;共40 分)
阅读下列短文,从每题所给的四个选项  A.B.C.D中选出最佳选项。
A
Unnoticed and unappreciated for five decades,a large female turtle (龟)with a stained(彩色的),leathery(粗而硬的) shell is now a precious commodity(物品)in Changsha’s old zoo.She is fed on a special diet of raw meat.Her small pool has been covered with glass which can defend it from bullets.A special camera monitors her movements.A guard is posted at night.
The purpose is simple:the turtle must not die.
Earlier this year,scientists concluded that she was the planet’s last known female Yangtze giant soft shell turtle.She is about 80 years old and weighs almost 90 pounds.
As it happens,the planet also has only one known male.He lives at a zoo the city of Suzhou.He is 100 years old and weighs about 200 pounds.They are the last hope of saving a species believed to be the largest freshwater turtles in the world.
“It’s a very dangerous situation,” said Peter Pritchard, a famous turtle expert in the United States,who has helped try to save the species.、
For many Chinese people,the turtle is the symbol of health and long life,but the last two Yangtze giant soft-shell creatures show the threatened state of wildlife and biodiversity(生物多样性)in China.Pollution, hunting and over development are destroying natural habitats,and also endangering the plant and the animal population.
China contains some of the world’s richest treasures of biodiversity, yet the latest major survey of plants and animals shows a discouraging picture.Nearly 40 percent of all mammal species in China are now endangered, Scientists say.For plants,the situation is worse;70 percent of all nonflowering plant species and 86 percent of flowering species are considered threatened.
46.Why is the turtle in Changsha specially cared?
A.She has been unnoticed and unappreiated five decades.
B.She can be sold at a high price.
C.She is the planet’s last known female Yangtze giant soft-shell turtle.
D.She is old and heavy.
47.Which of the following statements is TRUE according to the text?
A.The turtle in Changsha is precious because it is the symbol of health and long life.
B.Peter Pritchard believes the female turtle is the largest freshwater turtle in the world.
C.The female turtle is in a dangerous situation where she may be killed.
D.The female turtle in Changsha and the male turtle in Suzhou are the last hope of saving the largest freshwater turtle species in the world.
48.According to the text ________in China.
A.there are the richest species of living things
B.wild plants and animals are becoming fewer
C.turtles are specially protected
D.the situation of plants is better than that of mammal species
49.The last paragraph proves the threatened state of wildlife and biodiversity in China by__________ .
A.facts and numbers                      B.Peter Pritchard’S words
C.teaching theory                        D.telling a story
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The huge explosion at Krakatau was the result of two different factors. One was that the volcano had not broken out for some time and so at the very center of the volcano there was an huge plug of lava, this acted like a cork(塞子) in a bottle, stopping the pressure below from being released(释放). The second factor was that ocean water entered the very centre of the volcano as the explosions became more violent. This caused superheated steam to build up enormous pressure and this was finally released in the largest explosion of all on August 27, 1883. The sudden release of the pressure sent huge amounts of ash, rock and dust into the sky. Some of the ash rose 80km into the air and traveled around the Earth causing brightly coloured sunsets for several years.
Krakatau almost disappeared; for many years after this explosion, it remained very quiet. However, there was still activity going on under the sea and on 25 January, 1925, a small volcanic cone appeared above the surface of the water. This new volcano was named Anak Kmkatau, or Child of Krakatau. Over the following years, the size of the island grew larger, by 1959, the island was 300 metres above the surface of the sea. The volcanic activity has continued and the latest eruptions were in 1995.
There is no doubt Krakatar will continue to grow and there is also strong evidence that at some point in the future there will be another violent explosion. Krakatau is in a part of the world where the surface of the Earth is unstable and is always moving and cracking. If, in the future, another “cork” becomes fixed in the centre of the volcano, the pressure will build up. A series of a smaller explosions will allow sea-water into the centre of the volcano and once again the result will a terribly destructive explosion.
66. The latest eruptions were in_______.
A.1925           B. 1959           C. 1995          D. 1983
67. The pressure under the volcano can not be released because _______
the plug looks like a cork in a bottle
the volcano hasn’t broken out for some time
the center of the volcano is blocked(堵塞) by lava
the temperature of the steam is not high enough.
68. We can infer from the article that Krakatau volcano________
A. has broken out three times               B. never dies but continues to be active
C. will kill many people again in the future    D. is always moving and growing above sea.
69. All of the following results are caused by the explosion at Krakatau EXCEPT that_____
A. ash, rock and dust was thrown high into the air
B. others small volcanoes were soon produced.
C. The island of Kratau was destroyed
D. People saw beautiful sunsets for some years
70. The article is mainly about________
A. the cause of the Krakatau volcano      B. the danger of the Krakatau volcano
C. the history of the Krakatau volcano     D. the future of the Krakatau volcano
题型:不详难度:| 查看答案

American and British researchers have proved that judgments based on how someone looks are important. They found that appearance tells a lot about your personality.
The researchers included Laura Naumann of Sonoma State University in California, and Simine Vazire of Washington University in Saint Louis, Missouri. They were joined by Sam Gosling of the University of Texas at Austin and Peter J. Rentfrow of Britain"s Cambridge University. The results of their study were published in the Personality and Social Psychology Bulletin in December, 2009.
The subjects(接受实验者)were asked to judge the personality of people they had never met. The judges examined pictures of one hundred twenty-three people. The people in the photographs had been told how to stand. They looked into the cameras without showing their feelings. The same people also were photographed the way they themselves wanted to stand. Those who wanted to smile could smile.
Then the judges attempted to decide what the people were like. The researchers compared the judges’ opinions with the way the people who were photographed thought of themselves. Three people who knew those in the photographs well also provided information about their personality and behavior.
The judges looked for ten qualities in the people in the pictures. The qualities included extroversion (having a confident character and enjoying the company of other people) and self-esteem (being satisfied with oneself).
The judges also looked for signs of loneliness, conscientiousness(正义), emotional control and religious and political beliefs.
The researchers said the judges could identify some personalities even when people were pictured in controlled positions. They could recognize personalities like extroversion and self-esteem. But it was hard for the judges to decide about most other personalities under the controlled conditions.
When the people smiled and stood naturally, however, judging their personalities was easy. Then the judges’ choices were correct for nine of the ten personalities.
Researcher Laura Nauman said that we live in the world where first impressions are important.
1. According to the passage, who were the judges?
A. The researchers of the study.                       B. The subjects in the study.
C. Parents and other adults.                               D. People in the photographs.
2. Which of the following qualities could the judges identify even when people were pictured in controlled positions?
A. Extroversion                   B. Religious beliefs              C. Loneliness         D. Emotional control
3. We can infer from the passage that ____________
A. the study was carried out by four researchers from America.
B. in the study126 people were photographed for judges to decide their personalities.
C. the Personality and Social Psychology Bulletin is an official publication(出版物).
D. it was hard to recognize personalities when the people were pictured with natural looks.
4. What will the author most probably talk about next?
A. The quality of the judges.                      B. The personalities of Laura Nauman.
C. Signs of emotional control.                   D. The reason why one’s appearance is important.
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