题目内容

What will power your house in the future?Nuclear,wind,or solar power?According to scientists at the Massachusetts Institute of Technology (MIT) in the US,it might be leaves — but artificial (人造的) ones.

Natural leaves are able to change sunlight and water into energy. It is known as photosynthesis (光合作用).Now researchers have found a way to imitate this seemingly simple process.

The artificial leaf developed by Daniel Nocera and his colleagues at MIT can be seen as a special silicon chip with catalysts (催化剂).Similar to natural leaves,it can split water into hydrogen and oxygen when put into a bucket of water. The hydrogen and oxygen gases are then stored in a fuel cell,which uses those two materials to produce electricity,located either on top of a house or beside the house.

Though the leaf is only about the shape of a poker card,scientists claimed that it is promising to be an inexpensive source of electricity in developing countries. “One can imagine villages in India and Africa not long from now purchasing an affordable basic power system based on this technology,” said Nocera at a conference of the American Chemical Society.

The artificial leaf is not a new idea. The first artificial leaf was invented in 1997 but was too expensive and unstable for practical use. The new leaf,by contrast,is made of cheap materials,easy to use and highly stable. In laboratory studies,Nocera showed that an artificial leaf prototype (原型) could operate continuously for at least 45 hours without a drop in activity.

The wonderful improvements come from Nocera's recent discovery of several powerful,new and inexpensive catalysts. These catalysts make the energy transformation inside the leaf more efficient with water and sunlight. Right now,the new leaf is about 10 times more efficient at carrying out photosynthesis than a natural one. Besides,the device can run in whatever water is available;that is,it doesn't need pure water. This is important for some countries that don't have access to pure water.

With the goal to “make each home its own power station” and “give energy to the poor”,scientists believe that the new technology could be widely used in developing countries,especially in India and rural China.

1.Which of the following orders correctly shows how the artificial leaf is used to produce electricity?

a.artificial leaves split water into hydrogen and oxygen

b.the hydrogen and oxygen gases are stored in a fuel cell

c.the artificial leaves are put in water

d.the fuel cell uses hydrogen and oxygen to produce electricity

A. c,a,b,d                               B.c,b,a,d  

C.b,c,a,d                 D.c,a,d,b

2.The purpose of the scientists at MIT in developing the new artificial leaf is to________.

A.build up more power stations in the world

B.provide cheaper energy for developing countries

C.offer people in developing countries access to pure water

D.gain a deeper understanding of the photosynthesis process

3.The main idea of this passage is ________.

A.an introduction to the history of artificial leaves

B.a mixture of water power and solar energy

C.giving energy to the poor

D.an invention copying photosynthesis

 

【答案】

 

1.A

2.B

3.D

【解析】

试题分析:本文介绍了一项仿造叶子光合作用的发明—人工叶子的工作原理、工作性能和工作条件,可为发展中国家提供便宜的能源。

1.细节题:根据第三段中“it can split water into hydrogen and oxygen when put into a bucket of water. The hydrogen and oxygen gases are then stored in a fuel cell,which uses those two materials to produce electricity,located either on top of a house or beside the house.”当把它投入一桶水中,可以把水分解成氢和氧。然后把氢和氧气体储存到放置在房间里或房子的旁边的燃料电池中,使用这两个材料来产生电能。由此可知正确顺序是A。故选A。

2.细节题:根据第四段中“scientists claimed that it is promising to be an inexpensive source of electricity in developing countries.”科学家声称,它可为发展中国家提供廉价的电力来源。故选B。

3.主旨题:阅读全文可知本文介绍了一项仿造叶子光合作用的发明—人工叶子的工作原理、工作性能和工作条件,可为发展中国家提供便宜的能源。故选D。

考点:考查科教类阅读

 

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Everyone knows about straight-A students. We see them frequently in TV situation comedies and in movies like Revenge(报复)of the Nerds. They get high grades, all right, but only by becoming dull laborers, their noses always stuck in a book. They are not good at social communication and look clumsy(笨拙的) while doing sports.

How, then, do we account for Domenica Roman or Paul Melendres?

Roman is on the tennis team at Fairmont Senior High School. She also sings in the choral group, serves on the student council and is a member of the mathematics society. For two years she has maintained A’s in every subject. Melendres, a freshman at the University of New Mexico, was student-body president at Valley High School in Albuquerque. He played soccer and basketball well, exhibited at the science fair, and meanwhile worked as a reporter on a local television station. Being a speech giver at the graduation ceremony, he achieved straight A’s in his regular classes, plus bonus points for A’s in two college-level courses.

How do super-achievers like Roman and Melendres do it? Brains aren’t the only answer. “Top grades don’t always go to the brightest students,” declares Herbert Walberg, a professor of education at the University of Illinois at Chicago, who has conducted major studies on super-achieving students. “Knowing how to make the most of your innate(天生的)abilities counts for more. Much more.”

In fact, Walberg says, students with high IQ sometimes don’t do as well as classmates with lower IQ. For them, learning comes too easily and they never find out how to get down.

Hard work isn’t the whole story, either. “It’s not how long you sit there with the books open,” said one of the many-A students we interviewed. “It’s what you do while you’re sitting.” Indeed, some of these students actually put in fewer hours of homework time than their lower-scoring classmates.

The kids at the top of the class get there by mastering a few basic techniques that others can readily learn.

1.The underlined word “nerds” can probably be________ .

A.dull bookworms lacking sports and social skills

B.successful top students popular with their peers

C.students with certain learning difficulties

D.born leaders crazy about social activities

2.What can we conclude from the first paragraph?

A.Most TV programs and films are about straight-A students.

B.People have unfavorable impression on straight-A students.

C.Everyone knows about straight-A students from TV or films.

D.Straight-A students are well admired by people in the society.

3.Some students become super-achievers mainly because_________ .

A.they are born cleverer than others

B.they work longer hours at study

C.they make full use of their abilities

D.they know the shortcut to success

4.What will be talked about after the last paragraph?

A.The interviews with more students.

B.The role IQ plays in learning well.

C.The techniques to be better learners.

D.The achievements top students make.

5.What can we infer from the passage?

A.IQ is more important than hard work in study.

B.The brightest students can never get low grades.

C.Top students certainly achieve all-around developments.

D.Students with average IQ can become super-achievers.

 

You’re rushing to work and a man ahead of you collapses on the sidewalk. Do you stop to help? In a study of by-standers, it was found that some people avert their gaze and keep on  walking rather than stop and get involved.

“There is a tendency to decide that no action is needed.” says a psychologist. “The first thoughts that pop into your mind often keep you from offering help. In order to take action, you have to work against them.” Here are some common thoughts that might prevent you from helping.

● Why should I be the one? I’m probably not the most competent(有能力的) person in this crowd. You might think someone older or with more medical knowledge should offer assistance.

● What if he doesn’t really need my help? The fear of embarrassment is powerful; no one wants to risk looking foolish in front of others.

● No one else looks concerned- this must not be a problem. We can follow the people around us, but most people tend to hold back their emotions in public.

“If you spot trouble and find yourself explaining inaction, force yourself to stop and evaluate the situation instead of walking on,” says the psychologist. “Then retry to involve other people; you don’t have to take on the entire responsibility of being helpful. Sometimes it’s just a matter of turning to the person next to you and saying, ‘It looks like we should do something.’ Or asking someone if an ambulance has been called and, if not, to call for one. Once you take action, most people will follow you.”

1.Which is NOT the common thought that stops you from helping others?

A.I’m not the very person capable of setting the problem.

B.It looks like we should do something.

C.It must not be a problem as no one else is concerned.

D.He doesn’t really need my help.

2.According to a study of by-standers, what will some people do when a man ahead falls down on the sidewalk?

A.They will call for help and then walk away.

B.They will stop and offer help.

C.They will turn away their eyes and go on walking.

D.They will laugh at him.

3.We learn from the last paragraph that if we spot trouble,          

A.we should call the ambulance as soon as we can.

B.we should take on the whole responsibility and do something alone.

C.we should stop and evaluate the situation and try to make other people follow.

D.we should turn to other people and ask them to take on the responsibility

4.In order to offer others your timely help, you need to        

A.ask others for help and call the police

B.get along well with the passers-by who spot the trouble

C.go directly to the police station

D.work against the first thoughts that prevent you offering help

5.The main purpose of the text is to tell readers        

A.to give others a hand                    B.to be more competent

C.not to risk looking foolish                 D.to stop and evaluate the situation

 

As the Internet’s influence grows, the potential for danger also escalates (逐步上升). One of these dangers is from cyber-bullying. Cyber-bullying (网络欺凌) is repeatedly hurting someone else through the use of technology. It consists of sending or posting cruel messages, photos, or videos on the Internet or other electronic media with the intent of damaging the reputation of the target. Imagine being a 13-year-old girl discovering a cell phone picture of her changing clothes for gym class has been sent to all her classmates. Or imagine being an 11-year-old boy who is scared to go to school because an unknown bully sent him an instant message saying that he is so fat that he should kill himself. Cases such as these are happening every day, leading kids to be depressed and unable to concentrate.
Worse yet, parents are oblivious (忽视的) to what is happening. Only 15 percent of parents even know what cyber-bullying is. And anyone who thinks that their child is not a victim or a bully is probably wrong. 90 percent of middle school students have had their feelings hurt online and 75 percent have admitted to visiting a website attacking another student.
Unlike traditional schoolyard bullying, where a bully has a name and a face, cyber-bullying gets much of its power from anonymity (匿名). A cyber bully might design a website posting cruel remarks about a classmate and never tell anyone that he or she was the creator. The cyber-bullying also gets its power from the scope (范围) of its audience. Within seconds, a cyber bully can send an e-mail to everyone he or she knows, inviting them to take part in an online poll (民意测验) of who is the ugliest kid in their class. Victims can be picked on day and night from any place.
The good news is that you can help stop cyber-bullying. By making parents and educators aware of what is going on and encouraging them to take quick and strong action when cyber-bullying cases happen, you can help make technology constructive, not destructive, for young people.

  1. 1.

    What can we learn from the second paragraph?

    1. A.
      Not many students have known of cyber-bullying.
    2. B.
      Parents may not know their child is a victim of cyber-bullying.
    3. C.
      Parents know a lot of cyber-bullying.
    4. D.
      Most of the students have not been hurt by cyber-bullying.
  2. 2.

    What does the author think of the cyber-bullying?

    1. A.
      It is not as harmful as people think.
    2. B.
      It is too complex a problem to settle.
    3. C.
      It will not affect the relationship between classmates.
    4. D.
      It can be stopped through our efforts.
  3. 3.

    What will probably be discussed in the following passage?

    1. A.
      How to prevent cyber-bullying.
    2. B.
      What parents and educators think of cyber-bullying.
    3. C.
      How to make parents aware of cyber-bullying.
    4. D.
      How to make good use of technology.

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