题目
题型：安徽省期中题难度：来源：
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. Burlier of the Microwave Research Center in Marlborough, New Hampshire.
Low-power microwaves only penetrate (贯穿) 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
50mw. / 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 (运动感应器)would turn on the
magnetron, filling the room with low-power microwaves. In the same way that a microwave 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(家畜) farmers.
Lambs that are born outdoors in winter, for example, are frequently lost to cold. Microwaves could warm
the lambs safely and quickly.
B. A new microwave oven.
C. A popular technique.
D. The magnetron.
heater?
B. It heats walls and furniture in a room.
C. It is safe.
D. It saves energy．
________________.
B. 40 mw. / sq. cm.
C. 60 mw. / sq. cm.
D. 85 mw. / sq. cm.
B. The motion detector.
C. The microwave oven.
D. The radiation-absorbing chemical.
B. Microwave heaters sometimes make people feel uncomfortable.
C. Perhaps microwave heaters will be first used by livestock farmers, who wish to protect their lambs in
winter.
答案
核心考点
试题【阅读理解。 Microwaves may be great at warming up food, but what about warming 】；主要考察你对题材分类等知识点的理解。[详细]
举一反三
lead the crowd in cheering for the team it likes best.
About five years ago. cheerleaders were considered to be simply entertainers. Today there is much
more Cheerleading in America which has become another form of athletic competition. Cheerleaders today
are expected to be gymnasts and dancers. They "are expected to be quick and strong.
Many cheerleaders are better athletes than the boys and girls on sports teams. High school
cheerleading especially has become more difficult. The students must be in top physical shape. They must
be able to jump high, turn circles in the air and lift each other. Teachers say this is the result of the influence
of college cheerleaders. High school students watch college football and basketball games on TV. They
see how the cheerleaders throw each other into the air and perform difficult athletic movements. They want
to do the same thing. There is one big difference between the two groups. however. College cheerleaders
in America are young men and women. The men do most of the lifting. At most high schools only girls are
cheerleaders. It"s very difficult for them to hold others on their shoulders and throw them into the air. There
are a number of ways high school cheerleaders are improving their skills. They are exercising and lifting
weights to increase their strength. And they are attending camps during the summer holidays to learn new
techniques. Cheerleaders test their skills by taking part in competitions against cheerleaders from other
schools. just like other athletes. Coaches at some high schools say this new kind of athletic cheer leading
has caused some problems .
They say girls who were soccer and basketball players are now competing for places on a cheer
leading team. As more girls attempt to become cheerleaders, sports teams suffer from a lack of good
players.
B. to cheer for their favorite teams
C. to be quick and strong
D. to be good high jumpers
nces is NOT true about cheerleaders? B. They are expected to be dancers and singers.
C. They must be in top physical shape.
D. They must be able to jump high.
B. it is easy for girls to be cheerleaders .
C. sports teams have no good players
D. more and more girls try to be cheerleaders
B . Why cheerleaders are so important.
C. What makes good cheerleaders and how they work.
D. Differences between college and high school cheerleaders .
in 2006. On June first she would begin a year as a national and international spokeswoman for education.
Kimberly Oliver was the first National Teacher of the Year from her state. She taught five-year-old
children at a public school in Maryland, near Washington, D.C. President Bush honored her and other
top teachers at the White House.
Kimberly Oliver said she wanted people to understand that the first several years of a child"s life were
the most important for learning. She said investing in children at a very young age would result in great
gains later in school and in life. She called on parents to read to children from an early age so they would
not fall behind in school. One of the activities at her school was an event called " Books and Supprer
Night ". Families read together at the school and received free books to take home. Parents, children and
teachers also ate dinner together.
Broad Acres Elementary School was in a poor area. Many of the parents were immigrants with limited
English. Kimberly Oliver helped improve learning environment at her school. She received money to buy
electronic learning systems, tape players and books in English and Spanish and sent them home with
students. Parents said she had shown them how to help their children at home.
She was born and raised in Delaware. She held one degree in English and another in Elementary
Education. Kimberly Oliver would follow in the footsteps of another teacher Jason Kamras from the
Washi
ngton area as National Teacher of the Year. Jason Kamras, as honored for his work, teaching mathto middle school students in the nation"s capital.
The National Teacher of the Year program began in 1952. A fourteen-member committee choose from
among teachers honored as the best in their states.
B. Kimberly Oliver had been teaching in a middle school for many years
C. Kimberly opened her own school early in Washington in 1952
D. many other teachers were given the honor together with Oliver
B. read to their children at an early age
C. not give too much money to their children
D. stay at school with their children more often
B. the elementary school she taught in is in a poor area
C. she was helpful ahd had many special and good ideas in teaching children
D. she called on parents to read to children from an early age
B. Maryland
C. New York
D. Washington
outburst. Suddenly it seems as if everyone is going to the movies, with ticket sales this year up 17.5
percent, to $1.7 billion.
And it is not just because ticket prices are higher. Attendance has also jumped, by nearly 16 percent. If
that pace continues through the year, it would amount to the biggest box-office increase in at least two
decades.
Americans, for the moment, just want to hide in a very dark place. People want to forget their troubles,
and they want to be with other people. Helping feed the outburst is the mix of movies, which have been
more audience-friendly in recent months as the studios have tried to adjust after the discouraging sales of
more serious films.
As she stood in line at the 18-screen Bridge theater complex here on Thursday to buy weekend tickets
for "Jonas Brothers: The 3D Concert Experience," Angel Hernandez was not thinking much about escaping
reality. Instead, Ms. Hernandez, a Los Angeles parking lot attendant and mother of four young girls, was
focused on one very specific reality: h
er wallet. "Spending hundreds of dollars to take them to Disneyland is ridiculous right now," she said. "For $60
and some candy money I can still be a good mom and give them a little fun."
A lot of parents may have been thinking the same thing Friday, as "Jonas Brothers" sold out more than
800 theaters, and was expected to sell a powerful $25 million or more in tickets.
The film industry appears to have had a hand in its recent good luck. Over the last year or two, studios
have released movies that are happier, scarier or just less depressing than what came before. After poor
results for a rush of serious dramas built around the Middle East, Hollywood got back to comedies.
B. People are richer with the development of economy.
C. More comedies are made than serious films.
D. People have to pay more to watch a movie.
B. she was a crazy movie fan
C. she was fond of Disneyland
D. she wanted to please her kids
movie industry?
B. $1.7 billion
C. $60
D. $25 million
B. following the order of time
C. describing problems and drawing a conclusion
D. making comparison of ideas
Popular music in America is what every student likes. Students carry small radios with earphones and
listen to music before class, after class and at lunch. Students with cars buy large speakers (扬声器) and
play the music loudly as they drive on the street.
Adult drivers listen to music on the car radio as they drive to work. They also listen to the news about
sports, the weather, politics, and activities of the American people. But most of the radio broadcast is
music.
Pop or popular musi
c singers make much money. They make a CD or tape which radio stations usein every state. Once the popular singer is heard throughout the country, young people buy his or her tapes. Some of the money from these tapes comes to the singer. Wherever the singer goes, all the young people want to meet him or her. Now the singer has become a national star.
Besides pop music, there are two other kinds of music that is important to Americans. One is called
folk music. It tells stories about the common life of Americans. The other is called western or country
music. This was started by cowboys who would sing at night to the cows they were watching. Today,
any music about country life and the love between a country boy and his girl is called western or country
music.
B. the weather
C. politics
D. music
B. Four.
C. Five.
D. Six.
B. Music Listeners
C. Cowboys in America
D. International Language
called food poisoning. Food poisoning is usually not serious, but some types are deadly. The symptoms
of food poisoning usually begin within hours of eating the poisoned food. Fever is one of the most
common symptoms.
Certain microorganisms(微生物)cause most types of food poisoning. Bacteria and other
microorganisms can poison eggs, meat, vegetables, and many other foods. After entering the body,
these tiny living things release poisons that make people sick.
Some chemicals can also cause food poisoning. They are often added to food while it is being grown,
processed, or prepared. For example, many farmers spray chemicals on crops to kill weeds and insects.
Some people may have a bad reaction to those chemicals when they eat the crops.
Some plants and animals contain natural poisons that are harmful to people. These include certain
kinds of seafood, grains, nuts, seeds, beans, and mushrooms.
When people handle food properly, the risk of food poisoning is very small. Microorganisms multiply
rapidly in dirty places and in warm temperatures. This means that people should never touch food with
dirty hands or put food on unwashed surfaces. Food should be kept in a refrigerator to stop
microorganisms from growing. Meat needs to be cooked thoroughly to kill any dangerous
microorganisms. People should also wash food covered with chemicals before eating it. Finally, people
should not eat wild mushrooms or other foods that grow in the wild. Some of these foods may contain
natural materials that are poisonous to humans. In addition, some types of fish can be poisonous.
Most people recover from food poisoning after a few days of resting and drinking extra water. If
people eat natural poisons, they must go to the hospital right away to have their stomachs emptied.
B. Food poisoning can be serious.
C. Food poisoning comes in varieties.
D. Food when poisoned can make people sick.
B. can be ignored
C. are too common to be noted
D. are always accompanied by a fever
B. low temperatures
C. some tiny living things
D. certain natural materials
B. vegetables are safer than meat and seafood
C. natural poisons are more dangerous than chemicals
D. different types of food should be handled differently
B. food poisoning can be kept under control
C. chemicals are needed in food processing
D. food poisoning is out of control
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