At the moment, there are two reliable ways to make electricity from sunlight. Yo
题型：不详难度：来源：
At the moment, there are two reliable ways to make electricity from sunlight. You can use a panel of solar cells to create the current directly, by liberating electrons from a semiconducting material such as silicon. Or you can concentrate the sun’s rays using mirrors, boil water with them, and employ the steam to drive a generator.
Both work. But both are expensive. Gang Chen of the Massachusetts Institute of Technology and Zhifeng Ren of Boston College therefore propose an alternative. They suggest that a phenomenon called the thermoelectric（热电）effect might be used instead—and they have built a prototype（原型）to show that the idea is practical.
Thermoelectric devices are not new. They are used, for example, to capture waste heat from car engines. They work because certain materials generate an electrical potential difference within themselves if one part is hotter than another. That can be used to drive a current through an external circuit.
The reason thermoelectric materials have not, in the past, been applied successfully to the question of solar power is that to get a worthwhile current you have to have a significant temperature difference. (200℃ is considered a good starting point.) In a car engine, that is easy. For sunlight, however, it means concentrating the heat in some way. And if you are going to the trouble of building mirrors to do that, you might as well go down the steam-generation route, which is a much more efficient way of producing electricity. If the heat concentration could be done without all the equipment of mirrors, though, thermoelectricity’s inefficiency would be balanced by the cheapness of the equipment.
In their view, three things are needed to create a workable solar-thermoelectric device. The first is to make sure that most of the sunlight which falls on it is absorbed, rather than being reflected. The second is to choose a thermoelectric material which conducts heat badly but electricity well. The third is to be certain that the temperature gradient（梯度）which that badly conducting material creates is not wasted by poor design.
小题1:The following methods can be adopted to make electricity from sunlight EXCEPT .
| A．putting a panel of solar cells into use |
| B．concentrating sun’s rays with mirrors |
| C．creating a solar-thermoelectric device |
| D．building a practical solar prototype |
| A．Because it’s hard for them to build enough mirrors to make it work. |
| B．Because 200℃ was hard to reach at that time even in a car engine. |
| C．Because of the failure of having a significant temperature difference. |
| D．Because it was hard to focus the sun’s rays with equipment of mirrors. |
| A．Thermoelectric Device --- the Best Method of All |
| B．A New Method of Making Electricity from Sunlight |
| C．How to Create a Workable Thermoelectric Device |
| D．Solar Power --- a New Energy Trend in the Future |
答案
小题1:D
小题2:C
小题3:B
解析
试题分析：传统的太阳能发电设备都很贵，这篇文章介绍的是太阳光发电的一个新的方法，既可以有效的发电，也可以节约设备的开支。
小题1:细节题：从第一段的句子：You can use a panel of solar cells to create the current directly, by liberating electrons from a semiconducting material such as silicon. Or you can concentrate the sun’s rays using mirrors, 可知用太阳能发电，可以用太阳能光板，用镜子，也可以用太阳能热点技术，没有提到D项。
小题2:细节题：从第四段的句子：The reason thermoelectric materials have not, in the past, been applied successfully to the question of solar power is that to get a worthwhile current you have to have a significant temperature difference. (200℃ is considered a good starting point.) 可知以前的热电材料应用失败的原因是没有有效的温度差，选C
小题3:标题确定题：从整篇文章和第二段的句子：Gang Chen of the Massachusetts Institute of Technology and Zhifeng Ren of Boston College therefore propose an alternative.可知这篇文章讲的是太阳光发电的一个新的方法。选B
举一反三
It doesn’t kill germs better than cooler water, but turning tap temperatures high, the US burns carbon equal to the emissions of Barbados.
People typically wash their hands seven times a day in the United States, but they do it at a far higher temperature than is necessary to kill germs, a new study says. The energy waste is equivalent to the fuel use of a small country.
It’s cold and flu season, when many people are concerned about avoiding germs. But forget what you think you know about hand washing, say researchers at Vanderbilt University. Chances are good that how you clean up is not helping you stay healthy; it is helping to make the planet sick.
Amanda R. Carrico, a research assistant professor at the Vanderbilt Institute for Energy and Environment in Tennessee, told National Geographic that hand washing is often “a case where people act in ways that they think are in their best interest, but they in fact have inaccurate beliefs or outdated perceptions.”
Carrico said, “It’s certainly true that heat kills bacteria, but if you were going to use hot water to kill them it would have to be way too hot for you to tolerate.”
She explained that boiling water, 212°F (99.98°C), is sometimes used to kill germs - for example, to clean drinking water that might be polluted with germs. But “hot” water for hand washing is generally within 104°F to 131°F (40°C to 55°C.) At the high end of that range, heat could kill some germs, but the sustained contact that would be required would scald the skin.
Carrico said that after a review of the scientific literature, her team found “no evidence that using hot water that a person could stand would have any benefit in killing bacteria.” Even water as cold as 40°F (4.4°C) appeared to reduce bacteria as well as hotter water, if hands were scrubbed, rinsed（冲洗）and dried properly.
In fact, she noted that hot water can often have an unfavorable effect on hygiene. “Warmer water can harm the skin and affect the protective layer on the outside, which can cause it to be less resistant to bacteria,” said Carrico.
Using hot water to wash hands is therefore unnecessary, as well as wasteful, Carrico said, particularly when it comes to the environment. According to her research, people use warm or hot water 64 percent of the time when they wash their hands. Using that number, Carrico’s team calculated a significant impact on the planet.
“Although the choice of water temperature during a single hand wash may appear minor, when multiplied by the nearly 800 billion hand washes performed by Americans each year, this practice results in more than 6 million metric tons of CO2 equivalent emissions annually,” she said.
That’s roughly equal to the emissions of two coal-fired power plants, or 1,250,000 passenger vehicles, over the course of a year. It’s higher than the greenhouse gas emissions of small countries like El Salvador or Armenia, and is about equivalent to the emissions of Barbados. If all US citizens washed their hands in cooler water, it would be like eliminating the energy-related carbon emissions of 299,700 US homes, or the total annual emissions from the US zinc or lead industries.
The researchers found that close to 70 percent of respondents said they believe that using hot water is more effective than warm, room temperature, or cold water, despite a lack of evidence backing that up, said Carrico. Her study noted research that showed a “strong cognitive（认知的） connection” between water temperature and hygiene in both the United States and Western Europe, compared to other countries, like Japan, where hot water is associated more with comfort than with health.
The researchers published their results in the July 2013 issue of International Journal of Consumer Studies. They recommended washing with water that is at a “comfortable” temperature, which they noted may be warmer in cold months and cooler in hot ones.
小题1:What does the writer mainly focus on when writing this passage?
| A．Whether hot water helps kill germs effectively in hand washing. |
| B．How hot water contributes to the serious worsening of our planet. |
| C．Why the consumption of hot water is unnecessary and wasteful. |
| D．What the advantages and disadvantages of using hot water are. |
| A．burn | B．improve | C．soften | D．wrinkle |
| A．two coal-fired power plants | B．US zinc or lead industries |
| C．1,250,000 passenger vehicles | D．El Salvador or Armenia |
A. Boiling water at 212°F (99.98°C) works effectively in killing germs.
B. Warmer water can damage the protective layer of the outside skin.
C. There is much difference between cold water and hot water in reducing bacteria.
D. Americans have inaccurate beliefs or outdated perceptions in hand washing.
小题5:Which of the following is the standard of a comfortable water temperature for washing hands?
A. Warmer in winter and cooler in summer.
B. Between 104°F to 131°F (40°C to 55°C).
C. Below 104°F (40°C) or above 131°F (55°C).
D. Warm enough to kill germs and clean up.
小题6: If you want to read stories of this kind afterwards, which of the following magazines will you probably subscribe to?
| A．Universal Science Fiction | B．Science & Discoveries |
| C．Environment & Protection | D．Exploration of America |
GOOD DAD:A man whose wife has died with a young family and a busy job as a lawyer, Gregory Peck"s character in the 1962 film is one of the great heroes of American cinema Firm but fair he teaches his children respect and human decency（正派)．Harper Lee"s novel gets a respectable transposition（转变)to film, thanks to Gregory Peck"s perfect performance.
Jack Torrance in The Shining
BAD DAD: When Jack Torrance ,his wife ,Wendy ,and son, Danny ,escaped from the cold winter to the Overlook Hotel we know that Jack has hardly been a model father But when Jack becomes extremely angry and tries to murder his family with an axe, Danny used his intelligence to defeat him and left him to freeze to death．
George Bailey in It"s a Wonderful life
GOOD DAD: James Stewart"s character is a father-of-four who is saved from the edge of suicide (自***)and realizes his positive effect on others lives．Much of the film is unpleasant, with George shouting at his children as he faces financial problems. But finally the lovable father realizes the worth of his own life, the value of friendship and the importance of being a loving dad
Darth Vader in The Empire Strikes Back（帝国大厦）
BAD DAD: When the unfriendly cyborg（半机器人）told Luke Skywalker that he was his father ,the son"s reaction says it all: "No! No!" It"s hardly a joyful welcome to the family. For most of his son"s life, Darth Vader has been an absent dad—and he has just cut off Luke"s hand You can understand why Father"s Day cards might not be available.
小题1:Who is Harper Lee?
| A． An actor. | B． A novelist | C． A movie director. | D． A translator. |
| A． Jack Torrance | B． Wendy | C． Danny | D． Darth Vader |
| A．To kill a Mockingbird | B．The Shining |
| C．It"s a Wonderful Lift | D．The Empire Strikes Book |
| A．He lost his hand in an accident |
| B．His father changed him into a cyborg. |
| C．He discovered that he had a cruel father: |
| D．His father lived with him for most of his life. |
If you go to sleep on your back, you’re a very open person. You normally trust people and you are easily influenced by fashion or new ideas. You don’t like to displease people. So you never express your real feelings. You’re quite shy and you aren’t quite sure of yourself.
If you sleep on your stomach, you are a rather secretive person. You worry a lot and you’re always easily upset. You always stick to your own opinions or judgment, but you don’t raise your hopes too much. You usually live for today not tomorrow. This means that you enjoy having a good time.
If you sleep curled up, you are probably a very nervous person. You have a low opinion of yourself and so you’re often defensive. You’re shy and you don’t normally like meeting people. You prefer to be on your own. You’re easily hurt.
If you sleep on your side, you have usually got a well—balanced personality. You know your strengths and weakness. You’re usually careful. You believe in yourself. You sometimes feel anxious, but you don’t often get sad. You always insist on what you think even if it makes people rather angry.
小题1:According to the passage, a person, who is not willing to change his mind and hard to deal with, probably sleeps .
| A．on his side | B．on his back | C．curled up | D．on his stomach |
| A．do things personally. | B．stay alone |
| C．keep things secret | D．trust others easily |
| A．The people sleeping on their stomachs and those sleeping on his backs. |
| B．The people sleeping on their sides and those sleeping curled up. |
| C．The people sleeping on their backs and those sleeping on their sides. |
| D．The people sleeping curled up and those sleeping on their stomach. |
| A．one’s sleeping position has something to do with one’s character. |
| B．everyone has got both real and secret personalities. |
| C．the position in which one goes to sleep is the most important one. |
| D．when awake, one does not show one’s secret personality. |
Scientists note that babies are strongly influenced by their environment. They say a baby will smile if her mother does something the baby likes. A baby learns to get the best care possible by smiling to please her mother or other caregiver. This is how babies learn to connect and communicate with other human beings.
One study shows that babies can learn before they are born. The researchers placed a tape recorder on the stomach of a pregnant woman. Then, they played a recording of a short story. On the day the baby was born, the researchers attempted to find if he knew the sounds of the story repeated while in his mother. They did this by placing a device in the mouth of the newborn baby. The baby would hear the story if he moved his mouth one way. If the baby moved his mouth the other way, he would hear a different story. The researchers say the baby clearly liked the story he heard before he was born. They say the baby would move his mouth so he could hear the story again and again.
Another study shows how mothers can strongly influence social development and language skills in their children. Researchers studied the children from the age of one month to three years. The researchers attempted to measure the sensitivity of the mothers. The women were considered sensitive if they supported their children’s activities and did not interfere unnecessarily. They tested the children for thinking and language development when they were three years old. Also, the researchers observed the women for signs of depression.
The children of depressed women did not do as well in tests as the children of women who did not suffer from depression. The children of depressed women did poorly in tests of language skills and understanding what they hear.
These children also were less cooperative and had more problems dealing with other people. The researchers noted that the sensitivity of the mothers was important to the intelligence development of their children. Children did better when their mothers were caring, even when they suffered from depression.
小题1:According to the passage, which of the following is NOT the factor that influences intelligence development in babies?
| A．The environment. | B．Mother’s sensitivity. |
| C．Their peers (同龄人) | D．Education before birth. |
| A．To prove that babies can learn before they are born. |
| B．To prove that babies can learn on the first day they are born. |
| C．To show mothers can strongly influence intelligence development in their babies. |
| D．To indicate early education has a deep effect on the babies’ language skills. |
| A．The children of depressed mothers who cared little for their children. |
| B．The children of women who did not suffer from depression. |
| C．The children of depressed but caring mothers. |
| D．Children with high communication abilities. |
| A．Scientific findings about how babies develop before birth. |
| B．Scientific findings about how the environment has an effect on babies’ intelligence. |
| C．A study shows babies are not able to learn things until they are rice or six months old. |
| D．Scientific findings about how intelligence develops in babies. |
● To save time and money, use the college’s bus system. Taking the bus to school is quick, easy and free in most college towns. You won’t have to locate or afford a place to park either. It’s also a good way to be environmentally aware.
● Save pennies on books by waiting until class starts. You might not even need all of the recommended books. New textbooks cost an arm and a leg. Try buying used textbooks — it’s a surefire way to save money and serves the purpose as well.
● Do never look at college life as an endless series of parties and social activities. But there is a whole lot more to college if you’re serious about graduating. Having a good college experience is all about balancing work and fun.
● Be aware that your living environment can largely affect your academic success. If the dorm doesn’t suit you, consider living at home with your family or renting your own apartment. The best location for your studies isn’t always your dorm. Find a quiet area, like the library, to do your work. Alternatively, buy some headphones that block out noise.
● Be mindful of your diet. Make healthy food choices and watch what you eat. Avoid foods that are processed or high in sugar. The “freshman 15” is real. Many college students gain at least 15 pounds during their freshmen year.
● While electives (选修课) can be helpful when figuring out your major, you shouldn’t entirely rely on them. Clubs and other organizations exist around. Get involved. Make sure, though, that you still have time to study. Having too much on your plate can hurt your grades.
小题1:Which of the following ideas can be financially wise?
| A．Driving your own car. | B．Buying used books. |
| C．Renting an apartment. | D．Attending activities. |
| A．academic failures | B．physical problems |
| C．traffic accidents | D．social activities |
| A．attend limited activities on campus |
| B．have little regular physical exercise |
| C．focus less on their academic work |
| D．take relaxed attitudes to their diets |
| A．using too much money for meals |
| B．eating too many unhealthy foods |
| C．taking part in too many after-class activities |
| D．taking an elective that has too many students |
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