A Battery’s Worst Nightmare(噩夢)
Portable electronics that can be carried about easily are only as good as their batteries and, let’s face it, batteries aren’t very good, especially when compared with, say, petrol, which packs 100 times a battery’s energy into an equal space. That’s why a large group of mechanical engineers (centered at the Massachusetts Institute of Technology, but with partners at other universities and companies) are hard at work in an effort to replace batteries with a tiny engine that runs on fuel. Imagine a battery-free life!When the fuel runs out in your laptop or mobile phone, you just fill up and go.
The engine, about the size of a ten-cent coin, starts with a combustion chamber (燃燒室) that burns hydrogen (氫). Its tiny parts are etched onto silicon wafers (硅片) in the same manner that computer parts are imprinted onto integrated circuits (集成電路). The first engine is made up of five wafers. And since these wafers could be produced in much the same way as computer chips, they could probably be produced quite cheaply.
But the devil in all this nice detail is efficiency(效率). Tiny engine parts don’t always behave like their scaled-up parts of the first engine. Something between the parts can slow down the work, according to Columbia University professor Luc Frechette, one of the engine’s designers. Extreme heat from the combustion chamber is also a problem, often leaking to other parts of the engine.
The scientists’ goal is to create an engine that will operate 10 times better than batteries do. Frechette says that a complete system, with all parts in place and working, will be set up in the next couple of years, but commercial models aren’t available until at least the end of the next ten years.
【小題1】.
. According to the passage, the title suggests that ________.
A.batteries should be greatly improved | B.petrol will be used instead of batteries |
C.the time of batteries will be gone forever | D.pollution caused by batteries must be prevented |
A.Problem. | B.Advantage. | C.Invention. | D.Technique. |
A.The new invention doesn’t need any fuel. |
B.The new engine has been produced in quantity. |
C.The new invention is much cheaper than the battery. |
D.The new engine needs to be improved before it’s on sale. |
A.To introduce a new invention to readers. | B.To persuade readers not to use batteries. |
C.To show us how the new invention works. | D.To declare when the engine will be on sale. |
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科目:高中英語 來源:2013屆浙江省寧波一中高三12月月考英語試卷(帶解析) 題型:閱讀理解
下面文章中有5處(第61-65題)需要添加小標(biāo)題。請從以下選項(A、B、C、D、E和F)中選出符合各段意思的小標(biāo)題,選項中有一項是多余選項。
A.Structure of a hurricane
B.Preparing for a Hurricane
C. How Hurricanes Move
D. How Hurricanes start
E. Hurricane Names
F. Hurricane Damage
Hurricanes
Hurricanes are gigantic tropical storms that can be hundreds of kilometers wide. They bring along very strong winds and a lot of rainfall. They often cause flooding near the coasts and sea levels rise.
1. __________________________
Hurricanes are born over tropical oceans, usually during late summer and early autumn. They need two things to get them started: heat and moist air. During the summer the ocean surface heats up and warm moist air starts to rise. Cool air sinks down to replace it. This creates an area of low pressure. The rotation of the earth creates winds around the center of such a low-pressure area. In the northern hemisphere the air moves counter clockwise, in the southern part clockwise. Such a system is called a cyclone. When warm air rises, it cools and creates clouds. Soon, thunderstorms form and it starts to rain.
All hurricanes begin as cyclones but not all cyclones become storms or hurricanes. Some die out a few days after they start. They don’t have enough energy to become a hurricane. When winds are stronger than 119 km an hour a storm officially becomes a hurricane.
2. __________________________
The center of a hurricane is called the eye, a calm area with little rainfall. It is about 30 to 50 km wide. Inside the eye the sea can rise up to one meter because the air moves up. The eye wall is around the eye. This is an area of thunderstorms, rain and the strongest winds—up to 300 km an hour. Then come long bands of rain clouds that are curved towards the center of the hurricane.
3. __________________________
In the northern hemisphere hurricanes normally move in a westward direction and then they turn north and northeast. Their path takes them away from the warm tropical water of the equator. When hurricanes move over colder water or over land they lose a lot of their energy. They slow down and as time goes on, they disappear. In the southern hemisphere their path leads them to the south and southeast.
4. __________________________
When a tropical storm forms over the Caribbean Sea it gets a name. Every year the first storm of the season is given a name that starts with the letter A, the second storm gets a name starting with B and so on. Years ago only women’ s names were used for tropical storms. Today male and female names alternate –for example, the first storm is named Alexandra, the second one Billy, then Catherine etc. Each year new names are used so that you can connect a storm to a certain year.
5. __________________________
Hurricanes are causing more and more damage throughout the Gulf Region, mainly because the population is constantly growing. Many things can be done to protect yourself and your property during a hurricane: Keep emergency supplies of food and water; keep a battery-powered radio ready in case the power goes out. Listen to the instructions you get; keep the gas tank of your car full, in case you have to leave quickly; protect your house by nailing plywood over the windows and doors. Tie down loose objects; find out which roads are best to take you away from the storm; leave your house as soon as you are ordered to evacuate, etc.
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科目:高中英語 來源:2014屆重慶市高三第一次月考英語卷(解析版) 題型:閱讀理解
The Healthy Habits Survey (調(diào)查) shows that only about one third of American seniors have correct habits. Here are some findings and expert advice.
1. How many times did you brush your teeth yesterday?
Finding: A full 33% of seniors brush their teeth only once a day.
Step: Remove the 300 types of bacteria in your mouth each morning with a battery-operated toothbrush. Brush gently for 2 minutes, at least twice a day.
2. How many times did you wash your hands or bathe yesterday?
Finding: Seniors, on average, bathe fewer than 3 days a week. And nearly 30%wash their hands only 4 times a day-half of the number doctors recommend.
Step: We touch our faces around 3,000 times a day-often inviting germs (病菌) to enter our mouth, nose, and eyes. Use toilet paper to avoid touching the door handle. And, most important, wash your hands often with hot running water and soap for 20 seconds.
3. How often do you think about fighting germs?
Finding: Seniors are not fighting germs as well as they should.
Step: Be aware of germs. Do you know it is not your toilet but your kitchen sponge (海綿) that can carry more germs than anything else? To kill these germs, keep your sponge in the microwave for 10 seconds.
1.What is found out about American seniors?
A. Most of them have good habits.
B. Nearly 30%of them bathe three days a week.
C. All of them are fighting germs better than expected.
D. About one third of them brush their teeth only once a day
2.Doctors suggest that people should wash their hands .
A. twice a day B. three times a day
C. four times a day D. eight times a day
3.Which of the following is true according to the text?
A. We should keep from touching our faces.
B. There are less than 300 types of bacteria in the mouth.
C. A kitchen sponge can carry more germs than a toilet.
D. We should wash our hands before touching a door handle.
4.The text probably comes from .
A. a guide book B. a popular magazine
C. a book review D. an official document
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科目:高中英語 來源:2011-2012學(xué)年河北省高三高考仿真模擬考試英語試卷(解析版) 題型:閱讀理解
There are two methods by which hydrogen (氫) can be used to power cars. The first way is to use hydrogen to drive the engine, in much the same way as many cars use gas. The second method is to use the reaction of hydrogen with oxygen in a battery, making the car a kind of electric one.
The dream of producing hydrogen in the car while driving along by electrolyzing(電解)water is a long way off, so we are still at the period of batteries and filling the tank with hydrogen gas. This is the difficulty for potential car users and producers. There are only sixteen hydrogen filling stations in Los Angeles and none in 99% of other cities worldwide.
Indeed, some of the big name automobile producers have pulled out of the race to put the first practical hydrogen car on the streets. Ford and GM have announced that they are pulling out in America and so has Renault in France.
However, the Japanese companies are pressing on. In fact, Honda introduced its first hydrogen fuel cell car in 1999. They are now producing second generation hydrogen car known as the FCX Clarity. Guess where they are available for sale? In only one city because of its filling stations.
Honda thinks that they could go into full-scale production of the FCX Clarity by 2020 if the world is prepared for them by then.
Then there are hydrogen-powered buses in several European cities including Amsterdam, Barcelona, Hamburg, London, Luxembourg and Madrid. Lotus, the makers of London taxis, have announced that they propose to manufacture hydrogen-powered taxis in time for the London Olympics.
So, the hydrogen vehicle is out there and the numbers will be growing fairly soon. The buses go back to their bus station, where an electrolyzing machine changes water into fuel for them to fill up on and the same will be the case for many of London’s taxis.
Unfortunately, getting fuel is not the only difficulty for the average motorist, a number of these vehicles cost about $300,000 each.
1.According to the text, hydrogen-powered buses ________.
A.can easily be filled up with gas. |
B.a(chǎn)re likely to sell well in the future. |
C.a(chǎn)re mainly used in the United States |
D.won’t be used in the London Olympics |
2.What does the underlined word “them” in paragraph 5 refer to?
A.Japanese companies |
B.Hydrogen buses |
C.The FCX Clarity |
D.Filling stations |
3.Where are hydrogen cars currently available for sale?
A.In Barcelona |
B.In Hamburg |
C.In London |
D.In Los Angeles |
4.We can learn from the text that ________.
A.there are sixty hydrogen filling stations all over the world |
B.hydrogen vehicles fueled by water will be very expensive |
C.Honda will mass-produce the FCX Clarity by 2012 |
D.Honda produced its first hydrogen car in 1989 |
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科目:高中英語 來源:2014屆陜西省高一下學(xué)期期中考試英語試卷(解析版) 題型:閱讀理解
Because earthquakes happen without warning, it’s important to take measures now to prepare. Because you don’t know where you will be when an earthquake happens, prepare some supplies for your home, workplace, and car.
1. Water
A person needs at least 1/2 gallon(加侖) of water daily just for drinking. Store at least 1 gallon of water per person per day and be prepared for a 72-hour period. It is suggested that you buy bottled water. Keep bottled water in its original container and do not open it until you need to use it. Also, do check the “use by” date.
2. Food
It’s always a practical idea to keep a supply of non-perishable(不易腐爛的) food on hand. Have an enough supply of canned food, powdered milk, dried fruits, non-salted nuts and canned juices for at least 72 hours.
3. Torch(手電筒) and spare batteries (電池)
Keep a torch beside your bed, at your place of work, and in your car. Do not use matches or candles after an earthquake until you are sure that no gas leaks(泄露).Prepare a battery-powered radio and spare batteries. Most telephones will be out of order, so radios will be your best source of information.
4. Clothes
If you live in a cold place, you must think about warmth. You might not have heat after an earthquake. Think about your clothing and bedding supplies.
1.Why should people prepare themselves for an earthquake?
A. Because earthquakes can be known before they happen.
B. Because earthquakes take place without warning.
C. Because earthquakes usually take place in the neighborhood.
D. Because it’s people’s daily work to prepare the earthquakes.
2.You should prepare all of the following except ______.
A. powdered milk B. fresh vegetables C. dried fruits D. canned juices
3.According to the article we know that ______.
A. we need to prepare some supplies only at home
B. a telephone is the most important prepared thing
C. after earthquakes you’d better use torch first but not matches
D. clothes are used to protect your head
4.If you live in a cold place, you should prepare _______.
A. some warm clothes and bedding supplies B. some hot water
C. some batteries D. some torches
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科目:高中英語 來源:20102011江西南昌高三第三次模擬測試英語試題 題型:閱讀理解
Britain's most popular lie has been disclosed, with one in four people admitting using "sorry I had no signal" when returning a missed mobile phone call, a survey found.
Researchers found the average Briton tells on average four lies every day or almost 1500 every year. Almost one in six men admitted they were most likely to lie to their wife or girlfriend, on average at least twice a day.The most popular lie was saying you had no mobile phone signal.with one in four people admitting regularly using the little white He.It usually came after they hit the "ignore" button when their mobile rang.
Three quarters of people think women are better Hare.The research found 46 per cent of girls have been caught lying, compared to 58 of men.
The second most common fib(無關(guān)緊要的謊言) is “I haven't got any cash on me" when asked for money by tramps (流浪者).beggars and Big Issue sellers."Nothing's wrong - I'm fine" came third followed by "You look lovely" and "Nice to see you".
Modern technology turned out to have contributed to many lies with "I didn't get your text" in 18th."Our server was down" in 20th and "My battery died" in 26th place.
Other lies to make the top ten included "I'll give you a ring", "We're just good friends" and "We'll have to meet up soon"."I'm on my way" and "No, your bum doesn't look big in that" completed the top ten.
Men tell the most fibs, coming out with five every day compared to women who lie just three times. In many cases perhaps it is better to flatter with a fib than destroy someone with the truth, according to a spokesman for OnePoll, which carried out the research of 4.300 adults.
1.Whether the person being called has pushed the "ignore" button or _____.the caller at the other end hears the same tone.
A.really has no signal B.can't get the text
C.has a battery failure D.a(chǎn)nswers the call
2.Most people think women are better liars because _____.
A.there're more women liars B.fewer women liars are found out
C.women tell less harmful lies D.women are harder to convince
3."Our server was down" is perhaps a lie told as an excuse for not _____.
A.inviting a friend to dinner B.responding to an e - mail
C.coming to a party on time D.cleaning one's room
4."You look lovely" and "I'm on my way" rank _____ on the popular - lie list.
A.3rd and 8th B.5th and 10th
C.4th and 9th D.5th and 12th
5.The OnePoll spokesman seems to think it's _____ for the British to lie so much.
A.puzzling B.disgusting C.impossible D.reasonable
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