A Battery’s Nightmare
Portable electronics that can be carried about easily are only as good as their batteries (电池) 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 mobile phone, you just fill up and go.
The engine---about the size of a ten-cent coin---starts with a combustion chamber (燃烧室) that burns hydrogen. Its tiny parts are etched (蚀刻) onto silicon wafers (硅片) in the same manner that computer parts are etched onto integrated circuits (集成电路). 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. Tiny engine parts don’t always behave like the bigger parts of the first engine. Something between the parts can slow down the works, according to Columbia University Professor LucFrechette, 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 operate. 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 likely until at least the end of the next ten years.
【小题1】According to the passage, the title suggests that _______ .

A. The engine in your body.

B. The location, size and heartbeat of a heart.

C. What happens when the heart beats?

D. How does your heart work?

E. How do we know about the heart?

F. What can a doctor tell by feeling your pulse?

71.  

    Your heart is located in your chest, a little to your left. This heart of yours, which is about the size of your two fists held together, beats about 90 times a minute. A grown person's heart beats about 60 to 80 times a minute. The heartbeat is not just the same in all persons, and it is not the same in any one person at all times.

72.  

    When your heart beats, it is pumping blood to all parts of your body. If you could examine your heart closely, you would see that it is really two pumps placed side by side, and working at the same time. Each pump has two parts, the upper part called the auricle (心房), and the lower part called the ventricle (心室). The auricles receive the blood as it comes into them after it has been pumped through the body. The ventricles pump the blood out. The right one pumps the blood to the lungs and the left one pumps the blood to all other parts of the body. At the top and bottom openings of each ventricle are valves (阀门) which make the blood go in only one direction.

73.  

    Your heart is sometimes called the engine or the motor in your body and sometimes called the pump. It works away, both day and night. First it pumps out some blood, rests for a few seconds, and then it pumps some more. In a normal day, the heart pumps about 2,500 gallons of blood from the auricles and ventricles.

74.  

    By using a stethoscope to listen to the heart, the doctor can tell whether your heart is beating evenly and whether the valves are closing tightly. The stethoscope makes these sounds so clear that the doctor can hear them easily. The stethoscope has an earpiece that he places on your chest and tubes that he places in his ear. The earpiece carries the sound or your heart's beating along the tubes to the doctor's ears, and it makes the sound seem much louder than it really is. The doctor could listen to your heartbeat by pulling his ear against your chest.

75.  

An easy experiment can help you understand what happens when the heart beats. You can do this experiment with a hollow rubber ball. Make a small hole in it, and fill the ball with water through the hole. When you squeeze the ball, you will notice how the water comes out in a spurt each time you squeeze. After each spurt the ball comes back to its round shape again. Something like this happens when your heart beats. The muscles in your heart grow smaller, or contract, and squeeze the blood out of the heart. Each time this happens, we say your heart is beating. Perhaps you have noticed that the doctor places his finger on the pulse in your wrist when you are ill. By doing this he can tell how fast your heart is beating.

Pupils work harder in lessons if they are taught by a man, a study has claimed. Male teachers are more likely to improve pupils' self-esteem and are judged by pupils to be more fair, according to a study published by the Department for Education.                                                             
But there is a significant shortage of male teachers, especially in primary schools, with reports last month indicating that almost one in three primaries has an all-female teaching staff. The latest figures heightened fears that schools are becoming dominated (主宰) by women and children are being denied access to male role models in the classroom.                        
Researchers at the London School of Economics and Westminster University conducted an experiment in which each of 1,200 pupils in 29 schools was given £2. They could use the money to "buy" up to 10 questions at a cost of 20p each, which they then had to answer. If they were right they were given an extra 20p, but if they were wrong they lost 20p. Boys and girls who had a male teacher chose on average almost half a question more than those taught by women, indicating that they had a more positive outlook on the rewards of effort, the the study said.                                            
Researchers wrote: "One of the most significant results featured in this experiment is the positive effect of male teachers on effort. The experiment suggests that higher ability pupils either believed that the teacher would reward them more favorably or had a preference for working hard to please the teacher."                                                     
According to the Good Teacher Training Guide, 86 per cent of new teachers entering primary schools are female, along with 62 per cent of those entering secondary schools.                                             
Professor Alan Smithers, of Buckingham University, said: "This is an interesting and somewhat surprising finding, but it does underline the importance of having a good mix of male and female teachers in classes."
【小题1】Which of the following is true of the passage?  

A．Researchers at the London School of Economics and Westminster University conducted an experiment.

B．Students could use the money to "buy" up to 10 questions and then had to answer them.

C．Boys and girls who had a male teacher chose on average almost half a question more than those taught by women.

D．The experiment shows that students taught by male teachers had a more positive outlook on the rewards of effort.

Pupils work harder in lessons if they are taught by a man, a study has claimed. Male teachers are more likely to improve pupils' self-esteem and are judged by pupils to be more fair, according to a study published by the Department for Education.                                                             

But there is a significant shortage of male teachers, especially in primary schools, with reports last month indicating that almost one in three primaries has an all-female teaching staff. The latest figures heightened fears that schools are becoming dominated (主宰) by women and children are being denied access to male role models in the classroom.                        

Researchers at the London School of Economics and Westminster University conducted an experiment in which each of 1,200 pupils in 29 schools was given £2. They could use the money to "buy" up to 10 questions at a cost of 20p each, which they then had to answer. If they were right they were given an extra 20p, but if they were wrong they lost 20p. Boys and girls who had a male teacher chose on average almost half a question more than those taught by women, indicating that they had a more positive outlook on the rewards of effort, the the study said.                                             

Researchers wrote: "One of the most significant results featured in this experiment is the positive effect of male teachers on effort. The experiment suggests that higher ability pupils either believed that the teacher would reward them more favorably or had a preference for working hard to please the teacher."                                                      

According to the Good Teacher Training Guide, 86 per cent of new teachers entering primary schools are female, along with 62 per cent of those entering secondary schools.                                             

Professor Alan Smithers, of Buckingham University, said: "This is an interesting and somewhat surprising finding, but it does underline the importance of having a good mix of male and female teachers in classes."

1.Which of the following is true of the passage?   

A. Male teachers are more fair than female teachers.

B. Now most primary schools are in need of teachers.

C. Most people are afraid that their children can't get access to male teachers.

D. The author thinks that male teachers are better than female teachers.

2.What is the author's attitude to the finding that pupils work harder in lessons if they are taught by a man?    

A. He is for the finding.

B. He is against the finding.

C. He doesn't show his opinion about it.

D. He thinks it’s interesting and somewhat surprising.

3.What does the author mainly tell us in the 3^rd paragraph?    

A. Researchers at the London School of Economics and Westminster University conducted an experiment.

B. Students could use the money to "buy" up to 10 questions and then had to answer them.

C. Boys and girls who had a male teacher chose on average almost half a question more than those taught by women.

D. The experiment shows that students taught by male teachers had a more positive outlook on the rewards of effort.

4.It can be inferred that         .   

A. one third of primaries has an all female staff

B. if a student is taught by a man teacher, he will think that if he works harder he will make greater progress

C. 86 per cent of new teachers entering primary schools are female

D. this finding is interesting and surprising

5.Where can we find the passage?    

A. It is from a PE section on the Internet.

B. It is from an educational magazine.

C. It comes from the social section of a newspaper.

D. It comes from an English teaching book.

Pupils work harder in lessons if they are taught by a man, a study has claimed. Male teachers are more likely to improve pupils' self-esteem and are judged by pupils to be more fair, according to a study published by the Department for Education.                                                             

But there is a significant shortage of male teachers, especially in primary schools, with reports last month indicating that almost one in three primaries has an all-female teaching staff. The latest figures heightened fears that schools are becoming dominated (主宰) by women and children are being denied access to male role models in the classroom.                        

Researchers at the London School of Economics and Westminster University conducted an experiment in which each of 1,200 pupils in 29 schools was given £2. They could use the money to "buy" up to 10 questions at a cost of 20p each, which they then had to answer. If they were right they were given an extra 20p, but if they were wrong they lost 20p. Boys and girls who had a male teacher chose on average almost half a question

more than those taught by women, indicating that they had a more positive outlook on the rewards of effort, the study said.

Researchers wrote: "One of the most significant results featured in this experiment is the positive effect of male teachers on effort. The experiment suggests that higher ability pupils either believed that the teacher would reward them more favorably or had a preference for working hard to please the teacher. "

According to the Good Teacher Training Guide, 86 per cent of new teachers entering primary schools are

female, along with 62 per cent of those entering secondary schools.

Professor Alan Smithers, of Buckingham University, said: "This is an interesting and somewhat surprising finding, but it does underline the importance of having a good mix of male and female teachers in classes."

56. Which of the following is true of the passage?   

A. Male teachers are more fair than female teachers.

B. Now most primary schools are in need of teachers.

C. The author thinks that male teachers are better than female teachers.

D. Most people are afraid that their children can't get access to male teachers.

57. What is the author's attitude to the finding that pupils work harder in lessons if they are taught by a man?    

A. He is for the finding.                                      B. He doesn't show his opinion about it.

C. He is against the finding.                                D. He thinks it’s interesting and somewhat surprising.

58. What does the author mainly tell us in the 3^rd paragraph?    

A. The experiment shows that students taught by male teachers had a more positive outlook on the rewards of effort.

B. Students could use the money to "buy" up to 10 questions and then had to answer them.

C. Boys and girls who had a male teacher chose on average almost half a question more than those taught by women.

D. Researchers at the London School of Economics and Westminster University conducted an experiment.

59. It can be inferred that         .   

A. if a student is taught by a man teacher, he will think that if he works harder he will make greater progress

B. one third of primaries has an all female staff

C. 86 per cent of new teachers entering primary schools are female

D. this finding is interesting and surprising

60. Where can we find the passage?    

A. It is from a PE section on the Internet.                   B. It comes from the social section of a newspaper.

C. It is from an educational magazine.                         D. It comes from an English teaching book.