Scientists from South Korea are trying to convert(转化)sound waves into electricit

Scientists from South Korea are trying to convert(转化)sound waves into electricit

题型:不详难度:来源:
Scientists from South Korea are trying to convert(转化)sound waves into electricity. The research could lead to charging a cell phone from a conversation or providing energy to the nation’s electricity system generated(产生)by the noise during rash-hour traffic.
“Just as speakers transform electrical signals into sound, the opposite process —turning sound into a source of electrical power — is possible,” said Young Jun Park and Sang-Woo Kim, the joint authors of a new article in the journal Advanced Materials.
Harvesting energy from phone calls and passing cars is based on materials known as piezoelectrics. When bent, piezoelectric materials turn that mechanical energy into electricity. Lots of materials are piezoelectric: cane sugar, quartz (石英)and even dried bone which could create an electrical charge when stressed. For decades, scientists have pumped electricity into piezoelectric materials for use in environmental sensors, speakers and other devices.
Over the past few years, however, scientists have made dramatic advances in getting electricity out of piezoelectric devices. In an experiment, by using sound waves, which at 100 decibels(分贝)were not quite as loud as a rock concert (a normal conversation is about 60-70 decibels), the South Korean scientists produced a mild electrical current of about 50 millivolts(毫伏). The average cell phone requires a few volts to function, several times the power this technology can currently produce.
“But the real question is whether there is enough surrounding noise to act as a power source as for a cell phone,” said McAlpine, a leading scientist. A consumer probably wouldn’t want to attend a rock concert or stand next to a passing train to charge his cell phone. The South Korean scientists agree but they expect to get a higher power output as they continue their work.
小题1:According to the two South Korean scientists, ________.
A.sound waves can travel faster than electricity
B.new materials can send cell phone signals better
C.using cell phones adds to heavy traffic in rush hour
D.electricity and sound can be transformed into each other
小题2:We know from the passage that piezoelectric materials ________.
A.can produce electricity when stressed
B.are good at changing electricity into sound
C.can reduce the noise of passing cars
D.have been widely used in phones and cars
小题3:It can be inferred from the South Korean scientists’ experiment that ________.
A.it is hard to change sound into electricity under current conditions
B.it is impossible to make use of loud sound
C.the technology has a long way to go to have a practical use
D.the technology can power cell phones easily
小题4:What McAlpine doubts about the technology is ________.
A.the noise pollutionB.the sound resource
C.the cost of piezoelectricsD.the safety of devices

答案

小题1:D
小题2:A
小题3:C
小题4:B
解析

试题分析:文章介绍韩国科学家的新研究,就是可以把声音转化成电这样就有可能用声音给手机充电,但也存在一些问题,这项研究还需要进一步研究。
小题1:细节题:从第二段的句子:“Just as speakers transform electrical signals into sound, the opposite process —turning sound into a source of electrical power — is possible,”可知电子信号和声音是可以相互转化的。选D
小题2:细节题:从第三段的句子:Lots of materials are piezoelectric: cane sugar, quartz (石英)and even dried bone which could create an electrical charge when stressed.可知答案是A
小题3:推理题:从最后一段的句子:“But the real question is whether there is enough surrounding noise to act as a power source as for a cell phone,”可知这项科技要想有实际用途还有很长的路要走。选C
小题4:细节题:从最后一段的句子:“But the real question is whether there is enough surrounding noise to act as a power source as for a cell phone,”可知McAlpine 对这个科技的怀疑是声音的来源。选B
点评:科普类短文会有一些专业术语,但并不影响做题,在解答这类问题时要求学生抓住题干文字信息,采用针对性方法进行阅读,答案在文章中可以直接找到。
举一反三
I was in my third year of teaching creative writing at a high school in New York, when one of my students, 15-year-old Mikey, gave me a note from his mother. It explained his absence from class the day before.
I had seen Mikey himself writing the note at his desk. Most parental-excuse notes I received were penned by my students. If I were to deal with them, I’d be busy 24 hours a day.
The forged excuse notes made a large pile, with writing that ranged from imaginative to crazy. The writers of those notes didn’t realize that honest excuse notes were usually dull: “Peter was late because the alarm clock didn’t go off.”
Isn’t it remarkable, I thought, how the students complained and said it was hard putting 200 words together on any subject? But when they produced excuse notes, they were brilliant.
So one day I typed out a dozen excuse notes and gave them to my classes. I said, “They’re supposed to be written by parents, but actually they are not. True, Mikey?” The students looked at me nervously.
“Now, this will be the first class to study the art of the excuse note --- the first class, ever, to practice writing them. You’re so lucky to have a teacher like me who has taken your best writing and turned it into a subject worthy of study. ”
Everyone smiled as I went on, “You used your imaginations. So try more now. Today I’d like you to write ‘An Excuse Note from Adam to God’ or ‘An Excuse Note from Eve to God’.” Heads went down. Pens raced across paper. For the first time ever I saw students so careful in their writing that they had to be asked to go to lunch by their friends.
The next day everyone had excuse notes. Heated discussions followed. The headmaster entered the classroom and walked up and down, looking at papers, and then said, “I’d like you to see me in my office.”
When I stepped into his office, he came to shake my hand and said, “I just want to tell you that that lesson, that task, whatever the hell you were doing, was great. Those kids were writing on the college level. Thank you. ”
小题1:What did the author do with the students found dishonest?
A.He reported them to the headmaster.B.He lectured them hard on honesty.
C.He had them take notes before lunch.D.He helped improve their writing skills.
小题2:The author found that compared with the true excuse notes, the produced ones by the students were usually__________.
A.less impressiveB.more imaginativeC.worse writtenD.less convincing
小题3:The author had the students practice writing excuse notes so that the students could learn_________.
A.the importance of being honestB.how to write excuse notes skillfully
C.the pleasure of creative writingD.how to be creative in writing
小题4:The underlined word “forged” in the second paragraph means “______”.
A.formerB.copiedC.falseD.honest
小题5:What did the headmaster think of the author’s way of teaching?
A.Effective. B.DifficultC.Misleading.D.Reasonable

题型:不详难度:| 查看答案
Four decades ago a group of college students visited the mountains of Borneo to examine moth (蛾) populations. Now a team of British scientists, including a member of the original trip, has returned to the same sites to repeat the survey. They have found that, due to rising temperatures, the insects now live 68 meters higher.
Global warming is forcing tropical (热带的) species uphill to escape the rising temperatures at a rate of nearly 2 meters a year, the new study from Borneo suggests.
Since this was the only chance to repeat the original survey, the scientist did everything they could to do it exactly the same way, going at the same time of year, in July and August, using photographs to find the exact original sites of the moth traps.
"While this is the first study of insects, a few other studies of tropical species are starting to appear," said Thomas. "If you look across all those studies, you’ll find the same results, and it’s extremely difficult to think of any other explanation for them."
While some species might survive by finding places on the mountains with temperatures similar to those of their original habitats, others may run out of habitat on the rocky peaks, warns the study.
In a paper in the journal Naturein 2004, Thomas and 13 other experts analyzed the habitats of 1,100 species on five continents, and estimated that on average one quarter were at risk of extinction.
Last year a paper published in the Public Library of Science in the US warned that the risk of extinction in the tropics was becoming more and more serious. The authors, Jana and Steven Vamosi, estimated that 20-45% of tropical species were at risk of extinction.
小题1:If the temperature continues to rise at the same rate for ten years, the insects will live about ______.
A.6.8 meters higherB.19 meters higher
C.34 meters higherD.68 meters higher
小题2:What’s the problem for some species moving up mountains?
A.There’ll be too little space.
B.The temperature will be much too low.
C.They will be at greater risk of extinction.
D.They’ll find it hard to adapt to the environment.
小题3:We can learn from the passage that ______.
A.this survey of moths has been carried out many times
B.some scientists have put forward other explanations for the results
C.scientists tried to repeat the original survey
D.20-45% of tropical species were estimated to be at risk of extinction in 2004
小题4:Which of the following has been mainly discussed in the passage?
A.Climate change forcing moths higher.
B.Protecting moths from extinction.
C.How to research tropical moths.
D.How to study moths living on mountains.

题型:不详难度:| 查看答案
People often hear each others" voices without ever seeing the faces they belong to. "Nowadays we are talking away on the phone without meeting people," says Seung-Jae Moon. And from business conference calls to chat lines, people often imagine they would recognize the speaker if they saw him or her. Seung-Jae Moon, a linguist of Korea found that, under certain conditions, they"re actually right.
Moon decided to see just how close those mental pictures match up with reality and if there was any relation to how people speak rather than what they are saying. He recorded 16 Koreans, half men and half women, reading the same passage, and took a full-body photo and head shot of each speaker. Then he played the tapes for 361 Koreans and 173 Americans who did not speak Korean and asked his subjects to match up voice and picture. The Korean participants viewing full-body photos were quite perceptive. A majority linked 6 of the 8 women to the correct voice and did so for 5 of the 8 men. With the Korean group shown only faces, accuracy plummeted, but more than 20 percent of the subjects selected the same incorrect picture. The Americans showed no accuracy in matching the foreign voices to photos, but they too were consistent in their errors. That disconnection reveals conflicting ideas of physical and vocal beauty. Moon asked people to pick a favorite face and voice. Seventy percent of the Koreans picked one voice, but there was no agreement on a face. Americans didn" t agree on either count. And over 65 percent of both Koreans and Americans did not match their favorite face with their favorite voice.
Moon hopes to use software to break voices into components like pitch and hoarseness to narrow down which elements trigger certain mental pictures. "If we can map which characteristics of the voice triggers what kind of linage, and it doesn"t matter whether that image is the right or wrong one of the actual speaker, then we can create an image through voice," he says. That capacity could help to create computer-synthesized voices tailored to conjure up specific associations — audio books for children that inspire motherly visages, or warning alerts that bring to mind a stern police officer.
小题1:People often think that they would ______ the speaker when they saw the speaker.
A.understandB.recognizeC.likeD.surprise
小题2:Moon decided to do the experiment to ______.
A.see how close mental pictures match up with reality
B.how people speak
C.see if there was any relation to how people speak rather than what they are saying
D.both A and C
小题3:He asked ______ Korean women to speak and recorded their voices.
A.12B.16 C.8D.10
小题4:______ were more perceptive in recognizing full-body photos.
A.The KoreansB.The American women
C.The Korean womenD.The Americans
小题5:______ percent of Koreans and Americans matched their favorite face with their favorite voice.
A.Less than 65B.Less than 35C.Over 65D.About 20

题型:不详难度:| 查看答案
A small town in Tasmania, an island off the south coast of mainland Australia, is making itself an environmental role model by becoming the country"s first plastic bag-free town.
Since April 28, Coles Bay"s population of 175 and its tourist shoppers have been using reusable paper or cloth bags to carry their shopping.
Ben Keamey, a local businessman who supports the bag ban, said it would cut  the amount of waste and prevent damage to native wildlife that try to eat the plastic.
"Most businesses here come from the tourism and that"s all based on the environment, so people were pretty supportive," he said.
Every year Australians use more than six billion plastic bags. More than half of these come from the supermarket. Since it takes years for the bags to biodegrade(生物递减分解), tens of millions end up polluting the environment. They kill about 100,000 sea-birds and animals, which mistake bags for food, every year.
Only in the past few months have major Australian supermarkets begun cutting on their use of plastic bags. Environmental groups are pushing for a plastic bag fee like that in Ireland. There, since plastic bags cost 10 pence (about 1 yuan) each, their use has been cut by 90 per cent.
Pollution caused by plastic bags is a big headache for countries all over the world. As early as 1999, Beijing said that only plastic bags of certain thickness could be used. This was to encourage them to be used again and again, since an average of six million plastic bags are used there every there every single day.
小题1:Which might be the best title for this passage?
A.Deadly Plastic BagsB.The End of Plastic Bags
C.How to Reuse Plastic BagsD.The Present Situation of Plastic Bags
小题2:Plastic bags will not be used by the native people of Coles Bay because they ______.
A.cause the environmental pollutionB.are not easy to be reused
C.are not as good as cloth bagsD.are not strong enough
小题3:Which of the following statements is NOT true?
A.Plastic bags kill many animals in Australia each year.
B.Most Australian supermarkets have begun cutting on their use of plastic bags.
C.People at Coles Bay think poor environment may affect their tourism.
D.You have to pay for the plastic bags if you go shopping in Ireland.
小题4:The example of Coles Bay is to show that ______.
A.people take serious actions to deal with the plastic bag problem
B.people begin to realise the harm of using plastic bags
C.Australia is the first country in solving the plastic bag problem
D.Australians are aware of the importance of protecting the small town
小题5:Which of the following measures on plastic bags is NOT mentioned in the passage?
A.To forbid to use them by law.
B.to charge fee for plastic bags.
C.To make them thick enough to be reuseable.
D.To make them environmentally friendly.

题型:不详难度:| 查看答案
"USA? Britain? Which country is better to study in?" We often hear such discussions. As China opens its doors, studying abroad has become a dream for many Chinese students. They want to learn about the world.
It"s true that studying abroad can help students develop themselves. Language skills will improve and it may be easier to find jobs.
But there are problems that should be considered(考虑). Language is the first. Students must spend a lot of time learning another language and getting used to a different culture.
Students must also learn to live without parents" care and deal with all kinds of things they haven"t had to do before, like looking after themselves. There are reports about Chinese students abroad sinking into an ocean of difficulties and giving up easily. When they have to take care of themselves, it is hard for students to study well.
Finally, studying abroad brings a heavy burden(负担) to the family. For most Chinese parents, the cost of studying abroad is very high. But is it worth it?
We know that there are many famous people who succeed in great things through their hard work in China. Liu Xiang is a good example. Once an American teacher invited him there but he refused. He kept training hard with his Chinese teacher. He surprised the world when he won a gold medal(金牌) at the Athens Olympics. So when you wonder which country is better to study in, consider whether studying abroad is the right choice(选择).
小题1:From the passage, we learn that many Chinese students dream about studying abroad to __________.
A.taste a new lifeB.make a lot of money
C.learn about the worldD.learn to look after themselves
小题2:The writer thinks __________ should be considered first before students study abroad.
A.placesB.timeC.moneyD.language
小题3:The writer mentions Liu Xiang in the passage in order to tell us that __________.
A.Chinese teachers are better than American ones
B.studying abroad is not the right choice
C.people can also be successful in China if they work hard
D.Liu Xiang was a gold medal winner
小题4:Which of the following is NOT true?
A.Studying abroad will cost students" families a lot of money.
B.Studying abroad will make it easy for students to learn well.
C.Studying abroad will help students to improve language skills.
D.Studying abroad will bring students a lot of difficulties in their life.

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