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 ones.Natur 题目和参考答案——青夏教育精英家教网—

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

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相关题目

随着科技的进步，多媒体已走进很多学校的课堂。课间休息时，有些学校利用它来播放音乐。假如昨天你班就“课间是否要播放音乐”展开了讨论。请你根据以下信息用英语写一篇短文，陈述讨论结果。

[写作内容]

1.讨论的时间和讨论的问题；

2.学生们的观点：

大多数学生认为：活跃气氛，放松，带来快乐，学习效率高。

部分学生认为：时间短，没效果；课间太吵，需要安静。

3.达成的共识：最好播放柔和并适合于中学生的音乐。

参考词汇：the class break, efficiency(效率), relaxation(放松), agreement(共识)

[写作要求] 句子结构准确，信息内容完整，篇章结构连贯

_______________________________________________________________________________

________________________________________________

阅读下面材料，在空白处填入适当的内容（1个单词）或括号内单词的正确形式。

There’s no one reason why women return to school. Going back to school provides private and public benefits. College graduates, generally enjoy higher salaries, 1. (employ) more consistently, and work in nicer conditions. College-educated people vote more, give more to charity, and rely 2. (little) on government support.

Making the switch from 3. (support) to supporting oneself can be a challenge, 4. often a necessary one. Financial 5. (dependent) for women is key, says Nancy Schlossberg, professor at University of Maryland. “I think 6. important for women to do some direct achievement, because chances are that women will live alone in later life, either divorced 7. never married.”

To Schlossberg, education is critical in the long run. She says, “ You are going to do much better than before 8. you have a good education; you are going to be happier than before on condition that you have 9. education that enables you to do what you have to do in life. The question is 10. you are ready at this time to go for it.

阅读下面材料，在空白处填入适当的内容（不多于3个单词）或括号内单词的正确形式。

How do learning habits influence learning results? It’s useful and necessary to discuss learning habits. There is a famous 1. (say) “Good habits lead to good endings”, which shows the importance of habits.

“An apple a day keeps the doctor away” also 2. (show) a healthy everyday habit helps to build up our body, Thus, good learning habits can help us gain great learning results, high scores and abundant knowledge 3. (include). At first, learning habits form our ways of thinking and attitude 4. the content of our learning. 5. (obvious), a good habit can help us to speed up to reach our destinations. As we can see, developing a good habit is so important that I would like to introduce one kind of good learning habits— keeping 6. learning diary every day. We can start the habit by 7. (write) a learning summary and remember to record something impressive and meaningful. Keep it in mind, 8. gradually we can gain this good learning habit and benefit from it.

What’s 9. (much), I find out that I still have some bad learning habits 10. well. I can only concentrate on reading for a short time, and I will conquer this problem by spending more efforts on concentration practice.

I believe that through my efforts, I can gain good learning results by having good habits.

书面表达

假如你是李华，你的外国笔友Mark 想了解你校的近况。正好你校正在开展“提倡节约、反对浪费”的活动。请根据下文的提示给Mark写一封电子邮件。

★节约用纸，废纸回收；

★节约用水，珍惜水源；

★节约用电，按时熄灯；

★节约用餐，不乱花钱。

注意：1. 词数100左右；

2. 可以适当增加细节，以使行文连贯；

3. 参考词汇：launch vt. 开展； thrift n. 节俭。

短文改错

本文中共有10处语言错误,每句最多有两处.错误涉及一个单词的增加,删除和修改.增加:把缺词处加一个漏字符号(∧),并在其下面写出该词.删除:把多余的词用斜线(＼)划掉.修改:在错的词下划一横线,并在该词下面写出修改后的词. 注意: 1.每处错误极其修改均限一词.2.只允许修改10处,多者从第11处不记分.

Mr. Smith had a 8-year-old son named Tony, who enjoyed listening to music very much. So he bought a piano to Tony, hoping that he can become a famous pianist one day. The little boy put her heart into practising the piano day after day and seemed enjoy every minute of it. However, half a year later, he told his father that he was tiring of practising the piano. Heard this, Mr. Smith said, “Tony, it is one thing to be fond of listen to music, but it is another thing to perform skillful by yourself. You can never play the piano well even if you don’t practise more.”

I was in a terrible mood. Two of my friends had gone to the movies the night before and hadn’t invited me. I was in my room thinking of ways to make them sorry when my father came in. “Want to go for a ride, today, Beck? It’s a beautiful day.”

“No! Leave me alone!” Those were the last words I said to him that morning.

My friends called and invited me to go to the mall with them a few hours later. I forgot to be mad at them and when I came home to find a note on the table. My mother put it where I would be sure to see it. “Dad has had an accident. Please meet us at Highland Park Hospital”.

When I reached the hospital, my mother came out and told me my father’s injuries were extensive. “Your father told the driver to leave him alone and just call 911, thank God! If he had moved Daddy, there’s no telling what might have happened. A broken rib（肋骨）might have pierced（穿透）a lung...”

My mother may have said more, but I didn’t hear. I didn’t hear anything except those terrible words: Leave me alone. My dad said them to save himself from being hurt more. How much had I hurt him when I hurled those words at him earlier in the day?

It was several days later that he was finally able to have a conversation. I held his hand gently, afraid of hurting him.

“Daddy… I am so sorry…”

“It’s okay, sweetheart. I’ll be okay. ”

“No,” I said, “I mean about what I said to you that day. You know, that morning?”

My father could no more tell a lie than he could fly. He looked at me and said. “Sweetheart, I don’t remember anything about that day, not before, during or after the accident. But I remember kissing you goodnight the night before. ”He managed a weak smile.

My English teacher once told me that words have immeasurable power. They can hurt or they can heal. And we all have the power to choose our words. I intend to do that very carefully from now on.

1.The author was in bad mood that morning because _______.

A. he couldn’t drive to the mall with his friends.

B. his father had a terrible accident

C. his father didn’t allow him to go out with his friends

D. his friends hadn’t invited him to the cinema

2.Why did the author say sorry to his father in the hospital?

A. Because he was rude to his father that morning.

B. Because he didn’t get along with his father.

C. Because he failed to come earlier after the accident.

D. Because he couldn’t look after his father in the hospital.

3.The reason why the author’s father said he forgot everything about that day is that _____

A. he had a poor memory

B. he didn’t hear what his son said

C. he lost his memory after the accident

D. he just wanted to comfort his son

4.What lesson did Beck learn from the matter?

A. Don’t hurt others with rude words.

B. Don’t treat your parents badly.

C. Don’t move the injured in an accident.

D. Don’t be angry with friends at small things.

完形填空

请阅读下面短文，从短文后各题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。

Years ago, a critical event occurred in my life that would change it forever. I met Kurt Kampmeir of Success Motivation Incorporation for breakfast. While we were ___ ,Kurt asked me, “ John, what is your for personal growth?

Never at a loss for words, I tried to find things in my life that might for growth. I told him about the many activities in which I was . And I went into a about how hard I worked and the gains I was making. I must have talked for ten minutes. Kurt patiently, but then he smiled and said, “You don’t have a personal plan for growth, do you?”

“No, I .

“You know,” Kurt said simply, “growth is not a(n) process.”

And that’s when it me. I wasn’t doing anything to make myself better. And at that moment, I made the : I will develop and follow a personal growth plan for my .

That night, I talked to my wife about my with Kurt and what I had learned. I her the workbook and tapes Kurt was selling. We that Kurt wasn’t just trying to make a sale. He was offering a for us to change our lives and achieve our dreams.

Several important things happened that day. First, we decided to the resources. But more importantly, we made a commitment to together as a couple. From that day on, we learned together, traveled together, and sacrificed together. It was a decision. While too many couples grow apart, we were growing together.

1.A. workingB. preparingC. thinkingD. eating

2.A. suggestionB. demandC. planD. request

3.A. appealB. lookC. callD. qualify

4.A. involvedB. trappedC. lostD. bathed

5.A. lectureB. speechC. discussionD. debate

6.A. calculatedB. listenedC. drankD. explained

7.A. eagerlyB. graduallyC. gratefullyD. finally

8.A. admittedB. interruptedC. apologizedD. complained

9.A. automaticB. slowC. independentD. changing

10.A. confusedB. informedC. pleasedD. hit

11.A. on loanB. on purposeC. on saleD. on balance

12.A. commentB. announcementC. decisionD. arrangement

13.A. lifeB. progressC. performanceD. investment

14.A. contractB. conversationC. negotiationD. argument

15.A. lentB. soldC. showedD. offered

16.A. recalledB. definedC. recognizedD. declared

17.A. toolB. methodC. wayD. rule

18.A. provideB. buyC. giveD. deliver

19.A. growB. surviveC. moveD. gather

20.A. difficultB. randomC. firmD. wise

In many ways , the education system in the US is not very different from ____in the UK.

A. that B. this C. one D. it

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