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.
a microwave heater?
B. It heats walls and furniture in a room.
C. It is safe.
D. It saves energy.
he receives about __________.
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.
D. Microwave heaters cannot be accepted by the public because they are somewhat unsafe.
(等级) for 18,000 teachers, many parents said they were giving the reports serious thought. Yet there
was an equal measure of skepticism among parents that test scores have any relationship with teachers"
competence.
Some said they already knew how good a teacher was by walking into the classroom or by
monitoring their children"s progress. "I"m the kind of person who likes to see for themselves," a father in
Queens said.
Others worried about how their fellow parents, perhaps ones with sharper elbows, might respond. Will
they demand a new teacher? Move their children to a new school?
Elizabeth Sane, the mother of a fourth grader at the Ella Baker School, a kindergarten-through-eighth-
grade school on the Upper East Side, said that her daughter was switched to a different teacher"s class
over the summer, and that it was "like adding salt to the wound" when she saw the high ratings for her
daughter"s previous teacher. Her daughter"s teacher this year did not receive a rating because he
previously taught high school.
Ms. Sane said that the rating was not the only factor that influenced how she assessed a teacher"s
performance, but that the data used for teacher evaluations mattered.
But other parents dropping their children off at the Ella Baker School said they did not trust teacher
ratings based on test scores any more than they wanted their children"s learning measured only by the
state exams.
"Some people take it as the final word, but it doesn"t change who they are as teachers. The ratings
aren"t accurate, and the whole student testing thing needs to be thrown out," said Lydia Delgado, whose
child is in the second grade.
B. All the teachers will receive a rating at the end of each semester,
C. Most parents took the teachers" ratings seriously.
D. About half of the parents doubted the ratings to be reliable.
B. With a good relationship with the school.
C. With a stong will to succeed.
D. With strong elbows physically.
B. regretted having sent her daughter to another class.
C. didn"t think her daughter"s previous teacher was better.
D. wanted her daughter to return to her previous class.
B. Ms. Sane evaluated a teacher"s performance only by the rating.
C. Lydia Delgado didn"t think the students" scores should be kept.
D. To give ratings to teachers will come to an end in the near future.
B. critical
C. indifferent
D. objective
One reaction to all the concern about tropical deforestation is a blank stare that asks the question,
"Since I don"t live there, what does it have to do with me?"
The answer is that your way of life, wherever you live in the world, is tied to the tropics in many
ways. If you live in a house, wash your hair, eat fruits and vegetables, drink soda, or drive a car, you
can be certain that you are affected by the loss of tropical forests.
Biologically, we are losing the richest regions on earth when, each minute, a piece of tropical forest,
the size of ten city blocks, disappears. As many as five million species of plants, animals, and insects
(40 to 50 percent of all living things) live there, and are being lost faster than they can be found and
described. Their loss is immeasurable.
Take rubber for example. For many uses, only natural rubber from trees will do. Synthetics are not
good enough. Today over half the world"s commercial rubber is produced in Malaysia and Indonesia,
while the Amazon"s rubber industry produces much of the world"s four million tons. And rubber is an
important material in making gloves, balloons, footwear and many sporting goods. Thousands of other
tropical plants are valuable for their industrial use.
Many scientists strongly believe that deforestation contributes to the greenhouse effect -or heating
of the earth from increased carbon dioxide in the atmosphere. As we destroy forests, we lose their
ability to change carbon dioxide into oxygen.
Carbon dioxide levels could double within the next half-century, warming the earth by as much as
4.5 degrees. The result? A partial melt-down of polar ice caps, raising sea levels as much as 24 feet;
even 15 feet could threaten anyone living within 35 miles of the coast. Unbelievable? Maybe. But
scientists warn that by the time we realise the severe effects of tropical deforestation, it will be 20
years too late.
Can tropical deforestation affect our everyday lives? Now, you should have got the answer.
B. tropical materials
C. man-made material
D. commercial rubber
B. persuade people to buy something synthetic
C. show us how important it is to protect the tropical forests
D. let people realise the effect of tropical deforestation
B. Many of our daily uses are related to the tropical forests.
C. Tropical plants can be used to make industrial products.
D. High carbon dioxide levels will make the earth warmer.
B. cold
C. supporting
D. opposed
B. the value of Tropical Forests
C. Tropical Forests and Our Life
D. The Greenhouse Effects W
![](http://img.shitiku.com.cn/uploads/allimg/20191212/20191212121632-38223.png)
Professor Wiseman expects thousands of people to take part in an experiment in controlling dreams.
Participants will download a specially designed iphone app that turns their phone into a dream factory.
Placed on the bed ,the phone can monitor when a sleeper is not moving, which suggests the onset of
dreaming. It then plays a carefully crafted (精心制作的)"soundscape"designed to produce pleasant
scenes such as walking in the woods, or lying on a beach. The idea is that this will influence dreaming,
causing dreamers to form fantasyland inspired by the sounds they are hearing. At the end of the dream
the app sounds a gentle alarm to wake the dreamer, who submits a brief description of the dream to a
"dream catcher"database(数据库).
Prof Wiseman, from the University of Hertfordshire, who is best known for his research on sleeps,
said,"Getting a good night"s sleep and having pleasant dreams promotes people"s productivity, and is
necessary for their mental and physical well being. Despite this we know very little about how to
influence dreams. This experiment aims to change that. "
As many as 10,000 people are expected to take part in the study, declared at the Edinburgh
International Science Festival. Prof Wiseman teamed up with app developers YUZA, which created
the" Dream:ON" software. Participants will be encouraged to share their dreams via Facebook and
Twitter.
A national survey conducted for the experiment found that 21% of people had trouble sleeping
and 15%suffered from unpleasant dreams. Prof Wiseman said people feeling low dreamed far more
than others, and often had negative dreams. "Perhaps improving their dreams might help them,"he
added.
The "Dream:ON" app can be downloaded for free from iTunes or via the project site, http:∥
dreamonapp.com.
B. Sweetening dreams.
C. Stopping unpleasant dreams.
D. Waking up dreamers.
B. To analyse mental effect on dreamers.
C. To set up a worldwide dream database.
D. To know about how to affect dreams.
B. lie on a beach with your smartphone on
C. present your dreams via Facebook and Twitter
D. design a pleasant situation according to the sound
B. background
C. starting
D. ending
feelings and emotions is therapeutic for children aged 13-17. Psychology professors Meyran
Boniel-Nissim and Azy Barak have found that a teenager writing a publicly-viewed blog on the Internet
is more effective for relieving stress rather than keeping a private diary. The study, published in the
journal Psychological Services, supports that expressing oneself through writing can be therapeutic.
To conduct the research, Boniel-Nissim and Barak randomly selected Israeli high school students
who displayed a certain degree of stress. The teenagers were then divided into six groups. Two groups
were asked to post blogs twice a week about their social difficulties, but only one of them was asked
to open the blogs for comments. The next set of groups were also asked to blog twice a week to post
about whatever was going on in their mind, again with one group allowing comments. The two control
groups were asked to keep an old-fashioned private diary.
The researchers then collected the blog posts and diaries to discuss the adolescents" emotional and
social position. From the research, they saw that the greatest improvement in mood was with the
bloggers who wrote about their personal troubles and allowed people to interact with their posts. The
research also noted that the comments were mostly positive and constructive. Boniel-Nissim and Barak
said that the commentators" interactions helped the bloggers while they were distressed. The conclusive
research noted that expressing yourself on the Internet not only let others know what was personally
going on with you, but also helped you figure out some things about yourself too.
B. addictive for children
C. making people feel calm and relaxed
D. able to be easily hurt
B. Those who suffered from stress.
C. Those who had never blogged before.
D. Those who had poor social skills.
B. they discuss their study on the blog
C. they keep a traditional diary
D. they comment on someone else"s blog
B. is most useful in improving one"s mood
C. is not an effective way to express one"s feelings
D. can help students see their problems better
smart student Jason Haffizulla. Jason got straight A"s and was determined to study medicine at Harvard,
yet this was his downfall. His physics teacher gave Jason a B, a mark Jason believed would undermine (损害) his entrance to Harvard. After receiving his B, Jason took a butcher knife to school and stabbed
his physics teacher.
How can someone as smart as Jason do something so dumb? Studies show there is little or no
correlation between IQ and emotional intelligence.
During my early university years, I regarded myself as an intelligent guy. I got good marks in
mathematics, physics, and other subjects. I thought such skills would surely give me a bright future.
After one year of study with decent marks, I began to see two major classes of students. The first
category of students turned up to few lectures, partied every weekend, enjoyed a great social life,
and did minimal work to pass courses. The second category of students were intelligent and hard
workers who got good grades and were very focused on their studies. Surely would these intelligent
and hard-working students find the great jobs before the other lazier class of students?
Not so. Students are often shocked upon graduation that their qualifications are not as important as
they once thought. Graduates enter the workforce only to realize that co-workers hate them and less
intelligent people are the ones receiving promotions.
Educational skills are useless in some industries when interpersonal skills are absent. You can have
great ideas, theories, and solve complex problems, but if you cannot effectively communicate in a
persuasive and exciting manner by relating to your fellow humans, you will face an uphill battle in
whatever challenges you encounter. It"s not that people dislike you because of your intelligence; it"s
that people dislike you because you"re rude and not understanding. The intelligent person with poor
communication skills is insensitive or unaware of others" emotions.
B. he was disappointed with his downfall
C. he was not smart enough at studies
D. he got a worse mark than usual
B. didn"t work hard
C. belonged to the first category of students
D. could keep a balance between social life and studies
B. they can"t settle the challenges they meet
C. they are envied for their intelligence
D. they are not understanding enough
B. what kind of students can succeed in college
C. smart people may have poorer communication skills
D. intelligent students will meet more challenges at work
- 1南部苏丹于当地时间2011年7月9日0时宣布正式从苏丹分离,并成立南苏丹共和国,成为世界上最新的国家。读图,完成下列要求
- 2dx + .
- 3阅读下面一首宋词,然后回答问题。浣溪沙秦观漠漠轻寒上小楼,晓阴无赖似穷秋①。淡烟流水画屏幽。 自在飞花轻似梦,无边丝雨细
- 4把下列带序号的句子组合成语意连贯的一段话并填入横线处。(只填序号)(4分)孟子身处一个弱肉强食,生存还是毁灭尚需思考何者
- 5指出下图所示倾倒液体的操作中的错误:(1)_____________________________。(2)______
- 62010年我国将继续实施积极的财政政策和适度宽松的货币政策,宏观上既要防止通货膨胀的苗头继续扩大,又要防止通货紧缩的趋势
- 7在“探究力的平行四边形定则”的实验中:(1)甲、乙两位同学所得到的实验结果如图所示,若用F表示两个分力F1、F2的合力,
- 8若PQ是圆x2+y2=9的弦,PQ的中点是(1,2),则直线PQ的方程是( )A.x+2y-3=0B.x+2y-5=0
- 9若x+2x=5,则x2+4x2=______.
- 10_________apples do you need and__________cheese does your mo
- 1学习和生活中常用到下列光学器具:①显微镜、②穿衣镜、③潜望镜、④老花镜、⑤汽车观后镜、⑥近视镜、⑦望远镜.其中应用时发生
- 2下面各项都有数字2,写出它们所代表意义:①2Al_______________;②2Cl-______________;
- 3已知定义在R上的奇函数f(x)满足f(x+2)=-f(x),则f(6)的值为( )。
- 4下列对有关名著名篇的说明,不正确的一项是[ ]A.大卫是一个遗腹子,母亲改嫁后,在继父家受尽虐待,母亲死后,继父
- 5He forbids his children ____________ sweets because they do
- 6把20欧的电阻R1跟60欧的电阻R2并联起来,接在电压是6伏的电源上,并联的总电阻是 _________欧,R1中的电流
- 7These trousers are dirty and wet — I’ll change into my _____
- 8读图1,阴影部分是我国某种水果种植主要分布区,甲、乙、丙代表我国一个省级行政区,回答问题:小题1:该水果种植面积最大的省
- 9“低碳经济,节能减排”是21世纪世界经济发展的新思路。”下列与之相悖的是( )A.开发水能、风能、太阳能、地热能、核
- 10I"m sorry you _____ the wonderful football game. It was just