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 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
科目：高中英語 來源： 題型：閱讀理解
B This wireless transmitter allows you to listen to music from your iPod/MP3 player, on your home or car stereo --- without any wires.
It acts like a miniature radio station, transmitting your music via the FM frequency to the nearest radio.
Simply plug the transmitter into the headphone hole of your MP3 player, select a frequency on the transmitter and then set your radio to that same frequency.
Then sit back and enjoy your digital music in full stereo sound wherever you are.
It Can be used with iPods, MP3 players, portable CD players, cassettes players, games consoles（控制臺）or even your laptop computer whenever you want to hear full stereo sound from your radio. Features include:
·LCD display with background lighting （shows time/date/ temperature）
·Full FM frequency range, so you can select the best performing frequency
·Choose from 2 power supplies: 2 AAA batteries or car charger（adaptor provided）
·4 memory channels for storing best performing FM frequencies
·Frequency response: 100Hz – 15000Hz
The unit is wireless so there are no disorganized cables.It is lightweight and easy to carry.
Adds a whole new part to your MP3 experience!
Takes 2 AAA batteries（not supplied）.Click here to buy batteries for this product…
GIFT STATS: iPod/ MP3 Transmitter
Measures: 7.5 x 4.5cm
Packaging: Gift pack
We can deliver this item to the UK, Europe, and North America.
56. You may find the above advertisement __________.
A. in a newspaper B. in a store window
C. in a website D. on a company notice-board
57. What is iPod/MP3 Transmitter?
A. An MP3 player which allows you to enjoy music wherever you are.
B. A kind of equipment that allows you to enjoy music from your iPod/MP3 player.
C. A mini radio station transmitting your music via the FM frequency to the nearest radio.
D. A radio that receives music from your MP3 player.
58. From the advertisement above, we can learn that __________.
A. the product can be used with a lot of electronic equipment
B. the transmitter can only be powered by 2 AAA batteries
C. the unit has organized cables so it is light and easy to carry
D. this item can be delivered to any place around the world
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科目：高中英語 來源： 題型：閱讀理解
For those who are conditioned to think that learning only happens in a classroom, the world of self-learning can be a little daunting. How do we best take 1 of these new opportunities?
Your interest in the subject is the essential driver of success. You can’t learn what you do not want to learn. Emotion is an important part of the learning 2 . If you are even moderately interested in a subject, give yourself a chance. The key is to get started. If you can create some pleasurable 3 , you may find that the subject grows on you.
Don’t expect to understand things, much less remember them, the first time you study them. Trust that things will get clearer 4 your brain comes to grips with new information. It is like a cross-word puzzle. As you start to put the pieces together, or string the words together, the full picture becomes clearer. The brain learns all the time, but 5 its own schedule. Learning does not take place according to a schedule laid down by a curriculum or teacher. Some things are easier to learn than others. Some things just take 6 to click in. Keep at it, and you will gradually find that things that seem difficult at first , will become easy with time.
Your brain is struggling to form patterns to 7 new input from your learning activities. Sometimes, no matter how long you focus on one subject, your brain is not going to pick it up. If you are stuck, move 8 . Then cover the same general information from a different source, a different book, or a podcast, or an online lecture or a video. Try to become a grazing learner, roaming the countryside, 9 a feedlot learner, just standing there in one spot. The broader your base, the easier it is to learn. Just as the “rich get richer”, the more you know, 10 you can learn.
Take full advantage of the Internet, iTunes, and 11 mobile devices, not to mention good old-fashioned books and magazines. Learn during “dead time”. Listen in your car, on the train, or 12 jogging. Have your learning with you while waiting in the doctor’s office, or listen while checking out at the supermarket. Anytime is 13 time. Remember, you are learning through exposure, not by nailing things down. It is more like moisture accumulation in a 14 , rather than building a brick wall.
The more varied your learning content, and the more varied the ways in which you learn, the 15 the puzzle will become. Different learning activities suit different people, at different times of the day. Vary your activities in order to keep your interest level 16 . Even if listening and reading work best for you, treat yourself to the odd video lecture, or get-together with other learners. This will renew your batteries.
The “l(fā)oneliness of the distance learner” is a thing of the 17 . Join a learning community on the web, where members share their knowledge and experience. Search for the communities that suit your interests and learning style. You will find encouragement, advice and stimulus from fellow learners, 18 from tutors, teachers and coaches. In these communities, you can measure your progress against your own goals, or compare your experience 19 that of other learners. You can even teach and help others, which is a great way to learn.
Never has it been easier nor more exciting to be a learner. Let constant learning be a major part of your life-style. The 20 will be constant, personally, socially, and professionally.
( ) 1. A. advantage B. place C. possession D. example
( ) 2. A. progress B. process C. pressure D. proposal
( ) 3. A. roads B. streets C. routines D. building
( ) 4. A. with B. if C. unless D. as
( ) 5. A. on B. to C. with D. for
( ) 6. A. shorter B. sooner C. longer D. lower
( ) 7. A. take with B. com with C. go with D. cope with
( ) 8. A. down B. on C. away D. off
( ) 9. A. more than B. less than C. rather than D. other than
( ) 10. A. less B. quicker C. lower D. more
( ) 11. A. same B. similar C. familiar D. various
( ) 12. A. while B. before C. after D. if
( ) 13. A. playing B. learning C. talking D. speaking
( ) 14. A. cloud B. sky C. earth D. sea
( ) 15. A. cleaner B. clearer C. harder D. lower
( ) 16. A. down B. up C. in D. out
( ) 17. A. present B. day C. past D. night
( ) 18. A. as long as B. as far as C. as well as D. as soon as
( ) 19. A. without B. with C. to D. beyond
( ) 20. A. awards B. words C. remarks D. rewards
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科目：高中英語 來源：2013屆山西省太原市第五中學高三4月月考英語試卷（帶解析） 題型：閱讀理解
China_is_going_green. In order to reduce air pollution and oilshortages, automobile manufacturers have announced their plans to develop hybrid vehicles (混合燃料汽車) for the Chinese market. Toyota's hybrid car Prius will be ready to drive in China this week. Let's have a look at the new car.
Any vehicle is a hybrid when it combines two or more sources of power. Hybrid cars run off a rechargeable battery and gasoline. Hybrid cars have special engines, which are smaller than traditional gasoline engines. They run at 99 percent of their power when the car is cruising (勻速行駛). A specially designed battery motor provides extra power for running up hills or when extra acceleration is needed.
Step into a Prius, and turn on the engine. The first thing you notice is how much quieter it is than a traditional car. At this point, the car's gasoline engine is dormant (休眠). The electric motor will provide power until the car reaches about 24 km/h. If you stay at a low speed, you are effectively driving an electric car, with no gasoline being used, and no waste gas gives off.
The onboard(車載的) computer makes the decision about when to use a gas engine, when to go electric, and when to use a combination of the two. If you go over 24 km/h, when you step on the gas pedal (油門), you are actually telling the computer how fast you want to go.
The electronic motor recharges automatically using a set of batteries. When driving at high speed, the gasoline engine not only powers the car, but also charges the batteries. Any time you use the brake, the electric motor in the wheels will work like a generator and produce electricity to recharge the batteries. As a consequence, the car's batteries will last for around 200,000 miles.
【小題1】The author writes this passage mainly to________.
| A．teach people how to drive a hybrid car |
| B．introduce a new kind of “green” car |
| C．show how to save their gasoline when driving a car |
| D．a(chǎn)nnounce plans to develop hybrid vehicles for China |
| A．there will be more and more green land in China |
| B．China is still young and lacking experience |
| C．China's new cars are combinations of different green models |
| D．China has started producing environmentally friendly cars |
| A．The hybrid cars reduce air pollution and oilshortages. |
| B．The car's gasoline engine doesn't work until it reaches about 24 km/h. |
| C．This kind of car is completely controlled by an onboard computer. |
| D．A specially designed battery motor provides extra power when needed. |
| A．They are powered by both a rechargeable battery and gasoline. |
| B．They are much quieter than traditional cars. |
| C．They only use 99 percent of their power to run up hills. |
| D．They have smaller engines than traditional gasoline ones. |
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科目：高中英語 來源：2012-2013學年福建省師大附中高二上學期期末考試英語試卷（帶解析） 題型：閱讀理解
From school to band practice, the Venturi Eclectic is an Earth-friendly way to get where you want to go. This battery-powered, zero-emission (meaning it doesn't pollute the air) vehicle runs mainly on renewable energy. Solar panels on the Eclectic's roof absorb sun rays when you're driving. On windy days, you can connect a machine to the car's roof that collects energy from the wind while you're parked. The Eclectic's top speed is 28 miles an hour; the battery lasts for 31 miles before it needs to be recharged. Zipping (迅速行進) around the neighborhood has never been better.
Here's an eco-friendly way to tell time: Simply fill the Bedol Water-powered Clock's tank (箱) with water, add some lemon juice, and the clock will display the time without the need for environmentally harmful batteries. There are two sets of metal electrodes(電極) inside the water tank. Water contains ions (離子) that carry negative and positive charges. These ions complete a charge between the electrodes, creating enough energy to power the clock. Just refill the tank every few weeks, and this clock will keep on ticking.
You’re having a blast at your friend’s birthday party. But when it's time to bring out the cake, everyone crowds around, blocking your view. No worries. Throw the Triops into the air, and this clever camera catches the view from above. The Triops can take three pictures at once, each from different angles. You can also record sounds and command the Triops to start shooting (拍攝)whenever it hears that noise. That's one smart camera.
【小題1】According to the passage, the Venturi Eclectic .
| A．is popular with businessmen |
| B．is suitable for a long trip |
| C．has only a little gas emission |
| D．can turn wind into energy |
| A．They don't need batteries. |
| B．They can be powered by water. |
| C．They are difficult to operate. |
| D．They are environmentally friendly. |
| A．looking at a picture | B．recording sounds |
| C．enjoying yourself | D．blowing out a candle |
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科目：高中英語 來源：2012-2013學年江蘇省啟東中學高一下學期期中考試英語試卷（帶解析） 題型：閱讀理解
Froli Cat Dart While cats require less attention compared to dogs, that doesn’t mean you can just leave them at home all day long. No sir, they too, need some level of attention and will have to keep themselves occupied mentally and physically too. Well, FroliCat Dart makes it possible. Just what is the FroliCat Dart all about? Well, for starters, this device delivers 360° rotation (旋轉) that will project laser patterns on the floor, letting your feline (貓科動物) friend chase after it. |
Portable USB Power Supply With modern gadgets, running out of juice happens to some of us more often, simply because today’s devices seem to suck up more juice than before. That’s why the Portable USB Power Supply comes in handy, being a best emergency charger for cell phones and other devices. Capable of holding a charge for up to three months when in standby, it will ship with adapter tips that cater for a certain variety of cell phone brands. |
Battery Powered Gloves For those living in the northern hemisphere(半球)，we are pretty sure that you have already stocked up on your winter supplies to make sure you remain nice and warm throughout the upcoming freezing months. Well, wearing a pair of the Battery Powered Hand Warming Gloves is necessary so as to keep your palms and fingers warm. These gloves come with battery-powered integral (不可缺的) heating elements which is capable of keeping your hands nice and warm for up to eight hours. It requires a quartet of AA batteries in each glove, and since both gloves are fully lined with a waterproof, breathable material, they might just come in handy during your next snowball fight. Too bad it comes only in one color—black. |
| A．It can make cats run around your house. |
| B．It can project laser patterns to make cats chase. |
| C．It can make cats much sleepier than before. |
| D．It can provide food and drink for cats. |
| A．Lack of power happens to some of us less often than before. |
| B．The adapter tips cater for all kinds of cell phone brands. |
| C．The Portable USB Power Supply can charge for some phones. |
| D．The Portable USB Power Supply can only last for three months. |
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