Microwaves may be great at warming up food, but what about warming people?
Using microwaves to directly heat owners of a room would save much of the energy wasted by heating walls and furniture. And despite popular ideas about microwaves, this technique would be safe, according to Charles R. Buffler of the Microwave Research Center in Marlborough, New Hampshire. Low-power microwaves only penetrate (貫穿) the skin (low-power microwave penetration in a ham is about 0.2 inches, for example) and with no negative effects.
To test this idea, Buffler subjected himself to microwaves in a special room using a standard 500-watt, 2459 MHz magnetron (磁控管). He found that a person will start to feel warmth at about 20 milliwatts per square centimeter (mw. /sq.cm.); a satisfactory feeling of warmth occurs between 35 and 50 mw./sq.cm. By comparison, a person standing in noonday summer sun feels the amount of 85 mw./sq.cm. And a frozen meat pie in your microwave oven receives about 1000 mw./sq. cm.
In houses of the future, each room could be provided with its own magnetron, says Buffler. When you stepped into the living room, for example, a motion detector would turn on the magnetron, filling the room with low-power microwaves. In the same way that a microwaves oven heats up a hamburger, but not the plate it’s on, you would feel warmth from the microwaves without changing the temperature of your coffee table. (You could, however, make your favorite easy chair even more comfortable by treating it with a radiation-absorbing chemical.)
While it might be some time before homeowners are comfortable enough with the idea to set up whole body microwave heaters in houses, Buffler says microwaves may attract livestock farmers. Lambs that are born outdoors in winter, for example, are frequently lost to cold. Microwaves could warm the lambs safely and quickly.
小題1: Which of the following can tell the main idea of the passage?
A．A new heating system. B．A new microwave oven.
C．A popular technique.D．The magnetron.
小題2: The test conducted by Buffler shows that when a person feels comfortable warmth, he receives about ____.
A．20 mw. / sq. cm.B．40 mw. / sq. cm.
C．60 mw. / sq. cm.D．85 mw. / sq. cm.
小題3: According to paragraph 4, which of the following fills the room with low-power microwaves?
A．The magnetron.B．The motion detector.
C．The microwave oven.D．The radiation-absorbing chemical.
小題4: Which of the following statements about microwave heaters would Buffler most probably agree with?
A．Microwave heaters will soon be widely used by homeowners.
B．Microwave heaters sometimes make people feel uncomfortable.
C．Microwave heaters will be probably first used by livestock farmers to protect their lambs in winter.
D．Microwave heaters cannot be accepted by the public because they are somewhat unsafe.
小題1:A小題1:B小題1:A小題1:C
略
練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

科目：高中英語 來源：不詳 題型：完形填空

完形填空（共15小題；每小題1分，滿分15分）
閱讀下面短文，掌握其大意，然后從下列各題所給的四個(gè)選項(xiàng)（A、B、C和D）中，選出最佳選項(xiàng)。
“Where is the bus? Why is it always late?” I asked myself. I was going to be late ___36___ the manager wasn’t going to be pleased. “Thank God, here it is!” The bus came round the corner and I got on. Ten minutes later I was walking into the ___37___ where I work. “Twenty-five past nine. I ___38___ the manager doesn’t notice.” But I was not ___39___.
“Smith!” shouted the manager. “Late again. What’s your ___40___ this time?” “I am afraid the bus was late, Mr. Brown.” “___41___ up earlier tomorrow! Anyway, go to your place at the counter. We’ll be opening in a few minutes.”
My first customer was a pretty girl wearing a red dress. ___42___ her was a young man of about 25. He seemed very ___43___, and every few seconds he looked towards the main entrance. The girl drew some money and ___44___ about opening an account. I gave her necessary ___45___ and she went out. ___46___, I noticed a tall man by the door, carrying something ___47___ with brown paper. Turning to my next customer, I was frightened to see a gun sticking out of his coat. The next moment a loud noise ___48___ my ears. Everything went black. I was falling… It seemed to be a long time ___49___ I opened my eyes and I found myself in bed! ___50___ shaking from the memory of this terrible dream, I got dressed and ran out of the house. ___51___, the bus wasn’t on time, and I got to the bank at 9:25.
“Smith!” the manager cried out in a voice like thunder. “___52___ of your excuses! Start work at once!” To my ___53___, the first customer was a girl ___54___ a red dress and behind her stood a man carrying something wrapped in brown paper. The ___55___! Sometimes life is full of coincidences (巧合)!
小題1:
A．a(chǎn)sB．butC．a(chǎn)ndD．or
小題2:
A．hotelB．shopC．bankD．restaurant
小題3:
A．believeB．thinkC．guessD．hope
小題4:
A．luckyB．happyC．sorryD．a(chǎn)ngry
小題5:
A．excuseB．ideaC．causeD．a(chǎn)nswer
小題6:
A．HurryB．SetC．CatchD．Get
小題7:
A．BeforeB．BehindC．BeyondD．Against
小題8:
A．nervousB．shyC．calmD．a(chǎn)ngry
小題9:
A．caredB．talkedC．a(chǎn)skedD．worried
小題10:
A．informationB．offerC．introductionD．support
小題11:
A．AgainB．ThenC．ThusD．However
小題12:
A．hiddenB．filledC．decoratedD．covered
小題13:
A．tookB．closedC．filledD．came
小題14:
A．beforeB．a(chǎn)fterC．whenD．that
小題15:
A．EvenB．StillC．JustD．Ever
小題16:
A．As usualB．For one thingC．In factD．In general
小題17:
A．LessB．PlentyC．MoreD．None
小題18:
A．pleasureB．surpriseC．joyD．regret
小題19:
A．ofB．withC．onD．in
小題20:
A．dreamB．storyC．a(chǎn)ffairD．incident

查看答案和解析>>

科目：高中英語 來源：不詳 題型：完形填空

Any housewife who went to the new supermarket wished to be the lucky customer who did not have to pay for her shopping. This was what the 　21　just inside the entrance 　22　.It said: “Remember,　23　,one of our customers gets 　24　goods. THIS MAY BE YOUR LUCKY DAY!” For quite a long time Mrs. Edwards　25, like many of her  26, to be the lucky customer. Unlike her friends, she never　27　hoping. The 　28　in the kitchen was full of things which she did not need. Her husband tried to advise her 　29　buying so many things but failed. She 　30　dreamed of the DAY when the manager of the supermarket would come up to her and say, “Madam, THIS IS YOUR LUCKY DAY. Everything in your 　31　doesn’t need to be paid!” One Friday afternoon Mrs. Edwards shopped  32　.But she was not the lucky customer. No sooner had she just put the things inside her 　33　than she found that she had forgotten to 　34　tea. She dashed back to the 　35　, got some tea and went towards the　36　.As she did so, she saw the 　37　came.　38　his hand he said, “I want to 　39　you. You are our LUCKY CUSTOMER this week! Everything you have in your basket　40　 !”
小題1:
A．noticeB．report C．boardD．newspaper
小題2:
A．didB．promisedC．madeD．a(chǎn)greed
小題3:
A．every day B．every monthC．twice a weekD．once a week
小題4:
A．excellent B．free C．extraD．unexpected
小題5:
A．waited B．came C．hoped D．went
小題6:
A．friends B．neighbors C．relatives D．customers
小題7:
A．got rid of B．got along with C．gave up D．gave out
小題8:
A．counterB．cushion C．food D．cupboard
小題9:
A．a(chǎn)gainst B．for C．with D．a(chǎn)bout
小題10:
A．often B．a(chǎn)lways C．usually D．seldom
小題11:
A．billB．handC．car D．basket
小題12:
A．a(chǎn)nxiously B．seriously C．crazily D．wonderfully
小題13:
A．pocketsB．car C．basket D．house
小題14:
A．buy B．find C．take D．have
小題15:
A．shop B．counterC．department D．supermarket
小題16:
A．door B．entrance C．cash-desk D．shelves
小題17:
A．secretary B．policeman C．manager D．salesman
小題18:
A．Putting out B．Holding out C．ShakingD．Waving
小題19:
A．congratulateB．tell C．informD．thank
小題20:
A．is yoursB．means nothingC．belongs to youD．costs nothing

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

Conjoined twins lead separate but active lives.
Lori and Reba have never been alone and they want to keep it that way.
The 40-year-old conjoined twins in Pennsylvania,US,have read about others locked together by an accident of birth who have been medically separated.But they insist only death can part them.
“We’ve never imagined a life divided,”Lori said.
Lori and Reba are joined together at the side of their heads,facing in opposite directions.Their blood supply is partly linked,but each has a separate brain.
Reba suffers from a disease which has left her completely dependent on her sister.
Lori wheels her everywhere they go in different professional directions.Lori worked in a laundry room at a hospital for six years before giving that up to allow Reba to try to become a country singer.
Her first song is called “The Fear of Being Alone”,which was inspired by Reba and Lori’s desire for togetherness.
Reba’s career has taken her across the United States, Europe and parts of Asia.
While the twins receive some money from the government, the earning from Reba’s concerts go to AIDS and cancer charities(慈善機(jī)構(gòu)).
The sisters have set goals for themselves. Reba looks forward to a successful career as a country singer, while Lori says she hopes to get married and have children.Lori said,”So when it comes, it comes. Meanwhile, I live wonderfully from day to day.”
小題1:When Lori said “We’ve never imagined a life divided”,she meant that       .
A．they don’t wish to be made separate
B．they think their case is beyond medical help
C．independent life would be too good to think of
D．they would die once separated
小題2:By leading separate lives,the topic means that       .
A. either of the two can look after herself       B .the twins do different things
C. they face in opposite directions       D. they are no longer conjoined now
小題3:When Reba gives performances as a country singer,Lori       .
A．works in a hospitalB．continues her college education
C．brings up her childrenD．looks after her sister
小題4:The twins lead active lives because they       .
A．a(chǎn)re tired of staying at home doing nothing
B．need more money
C．want to prove themselves as useful citizens
D．have to earn their own bread
小題5:From the last paragraph we can understand that Lori       .
A. thinks it’s too late for her to have children  
B. is sure she’ll get married and have children

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

“Dr.Papaderos,what is the meaning of life?”
The usual laughter followed,and people stirred(騷動(dòng))to go.Papaderos held up his hand and stilled the room and looked at me for a long time,asking with his eyes if I was serious and seeing from my eyes that I was.
“I will,answer your question.”
Taking his wallet out of his hip pocket,he fished into a leather billfold and brought out a very small round mirror,about the size of a quarter.And what he said went like this:
“When I was a small child,during the war,we were very poor and we lived in a remote village.One day,on the road,I found the broken pieces of a mirror.A German motorcycle had been wrecked in that place.
I tried to find all the pieces and put them together,but it was not possible,so I kept only the largest piece.This one,and,by scratching it on a stone.I made it round. I began to play with it as a toy and became fascinated by the fact that I could reflect light into dark places where the sun would never shine——in deep holes and crevices(裂縫)and dark closets. It became a game for me to get light into the most inaccessible places I could find.
I kept the little mirror,and,as I went about my growing up,I would take it out in idle moments and continue the challenge of the game.As I became a man,I grew to understand that this was not just a child’s game but a metaphor for what I might do with my life.I came to understand that I am not the light or the source of light.But light——truth,understanding,knowledge——is there,and it will shine in many dark places only if I reflect it.
I am a fragment(碎片)of a mirror whose whole design and shape l do not know.Nevertheless,with what I have I can reflect light into the dark places of this world——into the black places in the hearts of men—and change some things in some people.Perhaps others may see and do likewise.This is what I am about.This is the meaning of my life.”
小題1:On hearing the author’s question,Dr.Papedotes       at first.
A．laughed at his foolishnessB．wasn’t sure of the answer
C．doubted his seriousnessD．wasn’t interested at all
小題2:How did Dr.Papaderos get the small round mirror when he was a child?
A．He found it on the road and made it round.
B．A dying German soldier gave him as a present.
C．He chanced to find it in the street while playing.
D．He put the broken pieces together and made it.
小題3:Why did Dr.Papaderos like the small round mirror so much as a child?
A．Because he was too poor to afford other toys.
B．Because it could shine the places where tke sun couldn’t reach.
C．Because he believed it would bring good luck to him.
D．Because it tofd him a lot about what life really meant to him.
小題4:The underlined“metaphor”in the 7th paragraph most probably means       .
A．symbolB．sourceC．lightD．purpose
小題5:Which of the following might be the best title for the passage?
A．A Special Game in the ChildhoodB．A Broken Piece of Mirror
C．Dr.Papaderos’ExperienceD．The Meaning of Life

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

There are three branches of medicine. One is called “doctor medicine” or “scientific medicine”. Scientific doctors try to observe sickness, look for logical pattern, and then find out how the human body works. From there they figure out what treatments may work. This kind of medicine is believed to date from the 4th century BC. Although nowadays it is successful, in the ancient this approach(方法) probably did not cure many patients.
The second kind of medicine is called “natural cures” or “folk medicine”, in which less educated people try to cure sickness with various herbs. These folk healers also use observation and logic, but they are not so aware of it. They try things until they find something that seems to work, and then they keep doing that. Folk medicine flourished(興起) long before the development of scientific medicine and was more successful in ancient times.
The third kind is called “health spas（水療）” or “faith healing”. Sometimes this may be as simple as touching the holy man and being immediately healed. Other times, a magician may make you a magic charm, or say a spell(咒語), to cure you. Some religious groups organize healing shrines(圣壇) for the sick. In these places people rest, get plenty of sleep, eat healthy food, drink water instead of wine, and exercise in various ways. They also talk to the priests(牧師) and pray to the gods. If you are feeling depressed or you have been working too hard, going to these places may be just the right thing to make you feel better.
小題1:Doctor medicine _________.
  1. has a longer history than folk medicine
  2. has been practiced for around 2,400 years
  3. bases its treatments on observation and logic
  4. was very successful in curing sicknesses in ancient times
小題2: According to the passage, which of the following is NOT used in health spas?
A．Magic powerB．Various herbsC．Religious faith D．A healthy life style
小題3:According to the passage, which of the following statements is true?
  1. Folk healers choose different herbs to cure diseases without any sound basis.
  2. People who practice folk medicine need lots of formal education on herbs.
  3. The success of folk medicine led to the development of doctor medicine.
  4. Natural cures worked better than scientific medicine in ancient times.
小題4: The author’s primary purpose in this passage is to_______________.
  1. describe different types of medicine
  2. argue for the importance of medicine in health care
  3. show the important role religion plays in medical treatments
  4. compare the educational background of three different types of patients
 

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

How the Americans view love
An old song says that " love makes the world go around" If you watch Americans on Valentine's Day, you can believe it. The whole country breaks out with little red hearts. Lovestruck people give cards, flowers and candy to their sweethearts.
The American concept of love and romance begins with dating. Young people date in several ways. At first they might have group dates with several boys and girls together. Later, they start going on single date - just one boy and one girl.
When two couples go out together, it's called double dating. A friend might even arrange a blind date for you with someone you don't know who your partner will be until the time of the date.
American young people see a date as a time just to have fun. They don't always have a romantic interest in mind. Someone may go out with one person this week, and another the next. After a while, a boy and a girl may decide they want to go steady. This means they think of each other as boyfriend and girlfriend. It also means they don't want to date anyone else. Romance is beginning to bloom.
Romance love is very much a part of American culture. Movies, TV shows and books in America all picture people falling in love. Actually, people all over the world search for happiness in a loving relationship. Maybe love does make the world go around.
小題1: How do you understand the understand sentence in the first paragraph?
A．Many young people's hearts break in America that day.
B．You can see many pictures of little red hearts all over America that day.
C．People all over the world show their hearts to each other that day.
D．people go out with their warm hearts that day
小題2:How many kinds of dates are mentioned in the passage?
A．2B．3C．4D．5
小題3:What does blind date mean?
A．You can not see who is your partner during the date.
B．The partner of your date is a stranger.
C．Your date is arranged secretly.
D．You will not know your partner until the date begins.
小題4: Which of the following statement is true about American's view of romantic?
A．Romance love is the most important thing in the world
B．People all over the world search for romance love
C．Date is one thing, romantic is another.
D．They can find their ideal love in movies, TV shows and books

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

閱讀理解E
Do you have a sore throat, a running nose and a headache? Do you keep coughing and sneezing? If you do, the chances are that you have a cold or perhaps flu---but which one? Although both colds and flu are caused by viruses, they are very different illnesses.
Colds, which usually last about a week, affect the nose most. They commonly cause a running nose and sneezing. Sometimes, they cause a headache, a cough and slightly aching muscles.
Flu is a much more serious illness and is caused by different groups of viruses. People with flu usually get all the symptoms(癥狀) described above. However, they also get a high fever, a dry cough and much worse aching. Fever is one of the characteristic symptoms of the flu for all ages. The symptoms also last much longer. Sometimes they don’t disappear for at least two weeks.
Flu can be a deadly disease. The elderly(年長的), who are weaker and less healthy than most younger people, can die from flu. This is one reason why old people are advised to have a flu injection(預(yù)防針) before the start of winter when flu is most common. This injection is inexpensive and definitely（明顯地）worth it.
If you have a cold or flu, you must always deal with used tissues(手巾紙) carefully. Don’t leave dirty tissues on your desk or on the floor. Someone else has to pick these up and viruses could be passed on. And finally, remember to cover your nose and mouth when you sneeze! You don’t want to see the small drops of liquids blown(噴) out of your nose and mouth when you sneeze, do you? Disgusting(令人作嘔), eh? Now you can understand why it’s a good idea to cover your nose and mouth when you sneeze!
小題1: In paragraph 4, we learn that ________.
A．flu injection can cause death
B．most old people die from flu
C．flu can kill old people easily
D．flu is most common in summer
小題2: Dealing with used tissues properly(正確地) is important because ________.
A．it helps keep your classroom tidy
B．it prevents the spread of colds and flu
C．people hate picking up dirty tissues
D．picking up lots of tissues is hard work
小題3: Which of the following statements is TRUE according to the passage?
A．Both colds and flu last the same time.
B．Both colds and flu can be prevented by injection.
C．Both colds and flu are caused by the same viruses.
D．Both colds and flu have an aching symptom.
小題4:Which is probably the best title for the passage?
A．Colds and Flu
B．The Different Symptoms of a Cold and Flu
C．Prevention Is Better Than Cure
D．Cover Your Nose and Mouth When Sneezing

查看答案和解析>>

科目：高中英語 來源：不詳 題型：閱讀理解

The two-week vacation at the end of summer school ended yesterday. Kevin had gone nowhere during his vacation. He had the money, but he hated to travel alone. He used to take vacations with Gary, his youngest brother, but they had a big argument at the end of their last vacation. Each of them had spent the last three years waiting for the other to apologize.
Kevin did not feel good about being on non-speaking terms with his favorite brother. But he was not going to ask for forgiveness when, in his mind, this whole misunderstanding was his brother’s fault.
So Kevin’s summer vacation was spent in his own “back yard.” As usual, he had planned to clean up his apartment. As usual, two weeks later his apartment looked just as it had two weeks before.
He did do one thing new and different during his vacation. There was a new coffee shop on Foothill Street. It served 25 varieties of delicious coffee at reasonable prices, and the staff was genuinely friendly. The shop was air-conditioned at a slightly chilly temperature. About eight small round tables were inside. Outside were four bigger tables. Each had four white metal chairs around it, and several big umbrellas provided shade. Even on hot afternoons, there was usually a pleasant breeze.
Kevin visited the coffee shop four times during his vacation. He always sat at a table outside by himself and read the free daily paper. Each day he was there, he read most of the newspaper articles while he enjoyed two cups of coffee.
Between articles, he took breaks by watching the nearby traffic and pedestrians. The coffee shop was next to a huge parking lot. The lot was for customers of a grocery store, movie rental store, pharmacy, bank, and restaurant. Kevin considered his outdoor seat the perfect place for one of his favorite activities—people watching.
The coffee shop, with its excellent location and coffee, had helped make his vacation a pleasant one. But he knew in his heart, had his brother been there to join him just one day, his vacation would have been a perfect one.
小題1: Why didn’t Kevin go anywhere during his vacation？
A．Because he was short of money.B．Because he didn’t like traveling.
C．Because he had no company.D．Because he had to clean up his apartment.
小題2: What did Kevin do in his vacation?
A．He cleaned up his apartment.B．He had a big argument with Gary.
C．He worked in a parking lot.D．He stayed at home most of the time.
小題3: Which of the following is NOT mentioned about the coffee house?
A．It served delicious coffee of different flavors.
B．It had an effective air-conditioning system.
C．It was often crowded with local customers.
D．It provided free newspapers for customers.

查看答案和解析>>

同步練習(xí)冊(cè)答案