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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
The text is most probably a ________.

A.science news report B.book review
C.newspaper ad D.science fiction

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

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
科目 英语   题型 阅读理解   难度 中等
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B
WASHINGTON – It’s a great achievement that inspires notions of robots with consciousness and independent minds.
When people or animals get hurt, they can usually compensate for minor injuries and keep limping along, but for robots, even slight damage can make them stumble and fall. However, a recently made robot has demonstrated a novel ability: it can heal its own damage.
The new robot, which looks like a splay – legged, four – footed starfish can sense injury to itself and adapt. That ability sets the new robot apart from earlier machines. Because the robot can recover from unfamiliar places. “There is a need for planetary robotic rovers to be able to fix things on their own,” says Josh Bongard, a professor in the University of Vermont, who is one of the device’s creator. “Robots on other planets must be able to continue their mission without human help if they are damaged and cannot communicate their problem back to Earth.”
A typical robot functions according to a computer program, but the new robot works differently. First, sensors in its four legs observe the robot’s movements and signals to its built – in computer. From the formation it collects, the robot creates its own programs that allow it to adapt to different situations. For example, when the researchers shortened one of the robot’s legs, the smart machine simply adjusted its way of walking – it used three legs instead of four.
The researchers are looking for other places to put the resilient robot to work. One pellicle spot is the ocean floor. That dark and dangerous undersea terrain might be a good choice for a robot the scientists call the Starfish. “We never officially named the robot, but we usually refer to it as the Starfish, even though a real starfish has five rather than four legs,” says Bongard. “Also, a real starfish is much better than our robot at recovering from injury, because it can actually grow its legs again.” Scientists have created robots that help humans in many ways: by exploring space, fighting fires, and even performing surgery.
46.The newly designed robot distinguishes itself from the former ones because it___________
A.can communicate with people on the earth about their problems
B.works according to a certain computer program
C.can find its problems and solve them automatically
D.can explore unfamiliar places
47.An example is given in the fourth paragraph in order to explain that the robot ___________
A.is used to create new programs
B.has typical robot functions
C.has sensors to observe its movements
D.can gather information and adapt to new conditions
48.The underlined word “resilient” in the last paragraph means the robot is ___________.
A.creative B.newly made C.able to recover D.informative
49.Which of the following is TURE about the robot “Starfish”?
A.It was spoken highly of by people for its special ability?
B.It will stumble and fall if damaged.
C.It can grow its legs again once they are broken.
D.It has started to work on the ocean floor.
50.What might be the best title of the passage?
A.How does the Starfish Robot work
B.Do – It – Yourself Robot Repair
C.Robots Designed to Work On Other Planets
D.New Robot Helping Us In Many Ways

III.阅读(共两节,满分40分)
第一节阅读理解(共15小题;每小题2分,满分30分)
阅读下列短文,从每题所给的A、B、C和D项中,选出最佳选项,并在答题卡上将该项涂黑。
A
Can you imagine a stranger will read your e – mails without your permission or scan the website you’ve visited or perhaps someone will casually glance through your credit card purchases or cell phone bills? All of the things may happen to you one day.
In fact,it’s likely that some of these things have already happened to you. Who would watch you without your permission? It might be a spouse, a girlfriend, a marketing company, a boss, a cop or a criminal. Whoever it is,they will see you in a way you never intended to be seen or even do something that may bring a disaster to you.
Psychologists tell us boundaries are healthy, and that it's important to reveal to friends, family and lovers at appropriate times. But few boundaries remain nowadays. The digital bread crumbs (碎屑) you leave everywhere make it easy for strangers to know who you are, where you are and what you like. In some cases, a simple Google search can leak the deepest thought in your mind. Like it or not, increasingly we live in a world where you simply cannot keep a secret.
The key question is:Does that matter? For many Americans, the answer apparently is “no”.
When opinion polls ask Americans about privacy, most of them say they are really concerned about losing it. And 60 percent of the respondents say they feel their privacy is “slipping away, and that bothers me”.
But people say one thing and do another.Only a small of Americans change any behaviors in an effort to preserve their privacy.Few people turn down a discount attollbooths (收费站)to avoid using the EZ—Pass system that can track automobile movements. Privacy economist Acquisti has run a series of tests that reveal people will give up personal information such as telephone number, address, or social security numbers just to get their hands on a pitiful 50-cents-off coupon(优惠券). But privacy does matter—at least sometimes.It's like health;when you have it,you don’t notice it.Only when it’s gone do you wish you’d done more to protect it. Without privacy, one will be naked in front of others.
41.What would psychologists advise on the relationships between friends?
A.Friends should open their hearts to each other.
B.Friends should always be faithful to each other.
C.There should be a distance even between friends.
D.There should be fewer quarrels between friends
42.Why does the author say “we live in a world where you simply cannot keep a secret”?
A.Modern society has finally developed into an open society.
B.People leave traces around when using modern technology.
C.There are always people who are curious about others’ affairs.
D.Many search engines profit by revealing people’s identities.
43.What do most Americans do about privacy protection?
A.They change behavior that might disclose their identity.
B.People turn down a discount at tollbooths to avoid using the EZ – Pass system.
C.They rely more and more on advanced technology.
D.They talk a lot but hardly do anything about it.
44.According to the passage,privacy is like health in that___________.
A.people will make every effort to keep it
B.its importance is hardly understood
C.It is something that can easily be lost
D.people don’t value it until they lose it
45.What would be the best title for the passage?
A.No privacy, no health.
B.Treasure your privacy.
C.Boundaries are important between friends.
D.The information age has its own shortcomings.

E
Computer mouse is no longer so strong. A Canadian engineer has invented a system that enables a computer user to push a cursor(光标)across a screen simply by moving his or her nose .He calls his nose-driven mouse a mouse.
The inventor ,Dmity Gorodnichy ,came up with the idea for the mouse while building computer software that would help astronauts operate the Canadarm—a long robotic arm on the U.S. space shuttle .His system employs a web-camera that recognizes a computer user’s nose from 25 pixels ,or points of light. Dmity chose the nose because its position remains relatively constant no matter which way the head moves .The system keeps track of the pixels, and the user matches the movements of his or her nose with the progress of the cursor across the screen.
The mouse keeps track of the eyes too. Two blinks(眨眼)are a “double click,” which turns the mouse on or off.
The mouse has received mixed comments from those who hold opposite opinions. One called it “a pointless waste of technology” . Another predicted that the nouse will fail to catch on because it makes users “look silly.” Dmity has already adapted the nouse for NousePong, a video game ,and NousePaint ,a drawing program.
He also predicts that the mouse will attract the people who have suffered from specific disease-pain ,senselessness ,or trembling in the hand caused by the frequent repetition of movements of the wrist and fingers ,such as typing at a computer keyboard .His next plan is to adapt the nouse for use by paralyzed(瘫痪)patients in hospitals .With two blinks of the eyes ,patients could double-click for help.
72.The best title for this passage is probably.
A.Mouse Driven by Nose
B.Cursor Moved Without fingers
C.New Computer System for Astronauts
D.New Type of Mouse for Patients
73.The nouse is a system working by means of .
A.keeping track of the points of light
B.moving one’s nose or blinking
C.moving cursor across the screen
D.matching the user’s nose with eyes
74.The underlined phrase “catch on” means “”.
A.become popular B.be used C.get improved D.be made
75.Dmity predicts that the nouse will be more used to help .
A.those who have eye trouble
B.develop a video game and drawing program
C.those traveling in space
D.the disabled with the hand and paralyzed patients

D
If you have a chance to go to Finland, you will probably be surprised to find how “foolish” the Finnish people are.
Take the taxi drivers for example. Taxis in Finland are mostly high-class Benz with a fare(车费) of two US dollars a kilometer. You can go anywhere in one, tell the driver to drop you at any place, say that you have some business to attend to, and then walk off without paying your fare. The driver would not show the least sign of anxiety.
The dining rooms in all big hotels not only serve their guests, but also serve outside diners. Hotel guests have their meals free, so they naturally go to the free dining rooms to have their meals. The most they would do to show their good faith is to wave their registration(登记) card to the waiter. With such a loose check, you can easily use any old registration card to take a couple of friends to dine free of charge.
The Finnish workers are paid by the hour. They are very much on their own as soon as they have agreed with the boss on the rate. From then on they just say how many hours they have worked and they will be paid accordingly.
With so many loopholes (漏洞)in everyday life, surely Finland must be a heaven to those who love to take “petty advantages”. But the strange thing is, all the taxi passengers would always come back to pay their fare after they have attended to their business; not a single outsider has ever been found in the free hotel dining rooms. And workers always give an honest account of the exact hours they put in. As the Finns always act on good faith in everything they do, living in such a society has turned everyone into a real “gentleman”.
68. The underlined words in this passage means to “______”。
A. be ready to help othersB. make good use of one’s friends
C. be a little ahead of others D. gain something at other’s loss
69. Which of the following is NOT true according to the passage?
A. While taking a taxi in Finland, you can get off without first paying your fare.
B. In a big hotel in Finland, you can enjoy free meals if you’re living in the hotel.
C. The bosses in Finland pay the employees according to registration of their working hours.
D. The workers are always honest with their working hours.
70. We can infer from the passage that ______.
A. the Finnish society is of very high moral level
B. there are many loopholes in everyday life in Finland
C. in Finland, most taxi drivers will not charge you anything
D. everyone in Finland is like a gentleman, for they have faith in themselves
71. Which of the following is the best title of the passage?
A. Life in Finland B. A Society with “Foolish” People
C.What a Life D. Honest accounts of the Finns

C
Perhaps you have a big test coming up and you are feeling nervous. You know you have got to do well. The pressure is on, so you may be losing sleep and the ability to concentrate. How can you deal with the stress, study effectively, and take the test with confidence? Maybe you should try meditation(沉思).
When people think about meditation, many pictures of old men’s sitting cross-legged on remote mountaintops will appear in mind. People describing meditation frequently mention elements such as relaxation and “thinking about nothing”.
It is not necessary to travel to a mountaintop to enjoy the benefits of meditation because it is actually more about awareness than just relaxation. The secret of meditation is breathing.
To star meditating, find a place where you can sit or stand comfortably for a little while and concentrate. Close your eyes and start taking slow breaths. Focus on the air moving in and out of your body. If your mind starts to wander and you begin to think about something else, refocus your attention on your breathing.
Meditation has little to do with escaping problems or thinking about nothing. Instead, the breathing techniques help you calm down and think more clearly about your feelings. The issues on your mind unfold clearly, as if they were in slow motion.
This clarity(清晰)is called “mindfulness”. Being mindful means that you are aware of what you are thinking without becoming caught up in your thoughts. It takes practice, but with time, that big test will not scare you anymore. You will realize through meditation that fear is just a product of not being mindful.
64. What is the best way to reduce the pressure if one faces a big test?
A. To climb up to the top of a mountain for a rest.
B. To sit on the top of a mountain without thinking anything.
C. To sit or stand comfortable and begin to meditate.
D. To sit quietly with one’s legs crossed.
65. What should a person do if his mind begins to wander while meditating?
A. Stop meditating.
B. Concentrate on breathing again.
C. Involve himself in his thoughts.
D. Close eyes immediately.
66. From the passage we can learn that by practicing meditation we’ll__________.
A. not be stuck in our thoughts
B. pass the examinations easily
C. realize fear is a product of too much thought
D. never be afraid of big tests
67. From the passage we can know the writer’s purpose is to let the readers know__________
A. how to deal with the stress before a big test
B. what is meditation
C. how a big test scares the students
D. where is the best place to relax

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