VOA慢速英语20061031b

SCIENCE IN THE NEWS - A Taxi at 12,000 Meters? New Mini Jets Are About to Shake Up World of Air TravelBy Brianna Blake, Jerilyn Watson and Nancy Steinbach

Broadcast: Tuesday, October 31, 2006

VOICE ONE:

This is SCIENCE IN THE NEWS in VOA Special English. I'm Bob Doughty¹.

VOICE TWO:

And I'm Faith Lapidus. This week: A big idea in small planes ...

VOICE ONE:

Scientists find that even on a bad hair day, the famous male lions of Tsavo still look good to the females ...

VOICE TWO:

And the science of autumn leaves.

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VOICE ONE:

Make room for some new arrivals in the market for small aircraft. The new airplanes are called very light jets. They are also known by other names including mini jets, microjets and air taxis. The Federal Aviation² Administration in the United States expects nearly five thousand to be in service by two thousand seventeen.

The new planes will cost up to fifty percent less than business jets now on the market.

VOICE TWO:


An Eclipse³ 500 at the EAA AirVenture Convention⁴ in Oshkosh, Wisconsin, in July

Eclipse Aviation of Albuquerque, New Mexico, proudly calls itself the manufacturer of the world's first very light jet. The plane is called the Eclipse Five Hundred. It can carry as many as six people. The cost? Just over one and one-half million dollars.

Eclipse has just produced the first plane for the first buyer, businessman David Crowe. And the company says it already has more than two thousand five hundred orders to meet over the next few years.

The Eclipse Five Hundred can fly at a top speed of six hundred eighty kilometers an hour. And it can travel one thousand six hundred kilometers without the need for more fuel.

The company says a top flight level of almost twelve thousand five hundred meters will avoid most severe weather.

VOICE ONE:

Another very light jet, the A-Seven Hundred AdamJet, is currently⁵ under flight testing by Adam Aircraft of Englewood, Colorado. The AdamJet is twelve meters long and can carry up to eight people.

With bigger planes, travelers often have to fly into big cities, then get a car and drive to smaller towns. The mini jets will be able to use smaller airports. In many cases the new aircraft are expected to be used as air taxis for short flights.

Very light jets are designed to be easier to fly than other jet planes. And some versions even include a bathroom for long flights.

VOICE TWO:

Other companies have also entered the market for very light jets -- including one of Japan's top carmakers. Honda Motor has developed the HondaJet.

Honda expects to produce seventy jets a year. It hopes to have them on the market in two thousand ten.


Michimasa Fujino, HondaJet project leader, answers questions at the same Wisconsin air show

In August, Honda established the Honda Aircraft Company, with headquarters in Greensboro, North Carolina. Honda appointed HondaJet chief engineer Michimasa Fujino to lead the new business. He spent the past twenty years working to develop a Honda aircraft.

The HondaJet can carry up to eight people. And, like the Eclipse Five Hundred and the AdamJet, it has two engines. But Honda officials say their plane will fly faster than other light jets of its kind. They say it will be able to reach speeds of almost seven hundred eighty kilometers per hour.

VOICE ONE:

Honda began sales of the HondaJet on October seventeenth. The price is more than three and one-half million dollars.

Very light jets are expected to be popular not just with air taxi companies and businesses whose employees travel a lot. They are also expected to appeal to wealthy people who want something a little sportier than a sports car.

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VOICE TWO:

You are listening to SCIENCE IN THE NEWS in VOA Special English.

In eighteen ninety-eight, two male lions attacked railway workers in the Tsavo [pronounced SAH-voh] area of what is now Kenya. It is said that the lions, over a period of nine months, ate more than one hundred thirty people.

A British military officer finally killed the two animals. He observed that they had no manes. Male lions are known for the thick hair along the top and sides of their necks. Yet other lions that the officer saw also had no manes.

The lions of Tsavo captured people's imaginations. They became the subject of scientific papers and books. The story was also told in the nineteen ninety-six motion picture The Ghost and the Darkness.

VOICE ONE:

Researchers, however, now report that most fully⁶ grown Tsavo lions do have manes. They found that this was true of eighty-seven percent of the ones they observed. But the Tsavo lions do not develop their manes as fast as other lions they were compared with.

The Journal of Zoology⁷ recently published the results of a study by a team from the Field Museum in Chicago, Illinois.

VOICE TWO:


A maneless male lion in Kenya's Tsavo National Park

The scientists followed the development of lions living in different parts of East Africa during a period of about seven years. They observed the lions in the hot Tsavo valley area of Kenya. They also studied lions in the cooler Serengeti mountains of Tanzania. The team reported that the difference in mane growth appears most closely linked to climate.

The Tsavo lions took eight years to fully develop their manes. The team observed that the lions began to develop their manes later and at a slower rate than the Serengeti lions. The Serengeti lions had longer, thicker manes that were fully grown by age four or five.

VOICE ONE:

The Serengeti lions reached sexual⁸ maturity⁹ about the same time their manes were fully developed. The Tsavo lions did not have full manes until after their most sexually¹⁰ active years. But the researchers say even fully grown Tsavo lions with poor manes still mated actively¹¹.

The findings suggest that a delay in mane development does not compromise the ability to reproduce¹². These findings conflict with other recent studies of lions. Some research found that female lions like to mate with males that have darker and more developed manes.

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VOICE TWO:

Leaves on many trees change color in autumn. But why?


Autumn leaves

(MUSIC)

The falling leaves drift by the window

The autumn leaves of red and gold

I see your lips, the summer kisses

The sun-burned hands I used to hold

VOICE ONE:

OK, more of Nat King Cole later. Here is how scientists explain why leaves change color in the fall.

In the spring and summer, leaves produce a green substance called chlorophyll. Chlorophyll changes sunlight, water and carbon dioxide in the air into food energy. Chlorophyll is also what makes leaves green.

Other chemicals in trees produce other colors. Carotenoids are orange, xanthophylls are yellow and anthocyanins are red.

Scientists say chlorophyll, carotenoids and xanthophylls are present in leaf cells all through the spring and summer. But the green chlorophyll blocks the yellow and orange colors.

In autumn, those colors can be seen because the leaves produce less and less chlorophyll, until the production stops.

VOICE TWO:

Red leaves are the result of anthocyanin production in autumn. Yet scientists are not sure about the purpose of anthocyanins. Some believe they protect the leaves from too much of the sun's radiation and protect cells from freezing during the cool autumn nights.

Others think anthocyanins may help leaves stay on a tree longer. They say the chemicals may make it possible for the tree to receive more growth chemicals from the leaves before the leaves fall off. The anthocyanins then stay inside the tree and its roots until they are needed again in the spring.

VOICE ONE:

Leaves fall off many kinds of trees when the weather cools. The leaves slowly close the veins¹³ that carry the growth chemicals. And special cells form where the leaves attach to the branches of the tree. These cells cause the leaves to separate from the tissues that connected them to the tree.

The color of autumn leaves may not be the same each year. The colors are affected¹⁴ by the amount of rain that a tree receives. Lack of rain can delay the appearance of the colors.

Warm, wet weather in the autumn will reduce the brightness¹⁵ of the colors that do appear. And extremely cold weather will kill the leaves and cause them to drop early in the season.

(MUSIC)

Since you went away the days grow long

And soon Ill hear old winters song

But I miss you most of all my darling

When autumn leaves start to fall

VOICE TWO:

SCIENCE IN THE NEWS was written by Brianna Blake, Jerilyn Watson and Nancy Steinbach. And special thanks to Kevin Tunison at the National Arboretum¹⁶ in Washington. I'm Bob Doughty.

VOICE ONE:

And I'm Faith Lapidus. Learn more about science, and download MP3 files of our programs, at www.unsv.com And be sure to listen again next week for more news about science in Special English on the Voice of America.

1 doughty   

adj.勇猛的，坚强的

参考例句：

• Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质：脾气倔强，性格刚强。
• The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。

2 aviation   

n.航空，航空学，飞机制造业

参考例句：

• Ten years ago,they began to develop the aviation. 十年前，他们开始发展航空工业。
• Pilots of large aircraft are masters of aviation.大型飞行器的驾驶员是航空学方面的专家。

3 eclipse   

v.使黯然失色，使相形见绌，日食，月食

参考例句：

• During the seventies,her acting career was in eclipse.在七十年代，她的表演生涯黯然失色。
• There will be an eclipse of the moon next month.下个月有月食。

4 convention   

n.惯例，习俗，常规，会议，大会

参考例句：

• How many delegates have checked in at the convention?大会已有多少代表报到？
• He sets at naught every convention of society.他轻视所有的社会习俗。

5 currently   

adv.通常地，普遍地，当前

参考例句：

• Currently it is not possible to reconcile this conflicting evidence.当前还未有可能去解释这一矛盾的例证。
• Our contracts are currently under review.我们的合同正在复查。

6 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

7 zoology   

n.动物学，生态

参考例句：

• I would like to brush up my zoology.我想重新温习一下动物学。
• The library didn't stock zoology textbooks.这家图书馆没有动物学教科书。

8 sexual   

adj.性的，两性的，性别的

参考例句：

• He was a person of gross sexual appetites.他是个性欲旺盛的人。
• It is socially irresponsible to refuse young people advice on sexual matters.拒绝向年轻人提供性方面的建议是对社会不负责任。

9 maturity   

n.成熟；完成；(支票、债券等)到期

参考例句：

• These plants ought to reach maturity after five years.这些植物五年后就该长成了。
• This is the period at which the body attains maturity.这是身体发育成熟的时期。

10 sexually   

adv.性别上地；按性别地；性欲地；两性之间地

参考例句：

• to be sexually promiscuous 性生活淫乱
• I was depressed,withdrawn and sexually frigid. 我郁郁寡欢，离群索居，没有什么性要求。 来自《简明英汉词典》

11 actively   

adv.积极地，勤奋地

参考例句：

• During this period all the students were actively participating.在这节课中所有的学生都积极参加。
• We are actively intervening to settle a quarrel.我们正在积极调解争执。

12 reproduce   

v.生育，繁殖，复制，重做

参考例句：

• The machine can reproduce a key in two minutes.这机器能在两分钟内复制一把钥匙。
• The picture will reproduce well.这照片会印得很清楚。

13 veins   

n.纹理；矿脉( vein的名词复数 )；静脉；叶脉；纹理

参考例句：

• The blood flows from the capillaries back into the veins. 血从毛细血管流回静脉。 来自《简明英汉词典》
• I felt a pleasant glow in all my veins from the wine. 喝过酒后我浑身的血都热烘烘的，感到很舒服。 来自《简明英汉词典》

14 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

15 brightness   

n.明亮，亮度，聪颖，光泽度，灯火通明

参考例句：

• The brightness of the paint has worn off a little.油漆的光泽有些磨损了。
• Her eyes squinted against the brightness.亮光刺得她眯起眼睛。

16 arboretum   

n.植物园

参考例句：

• We can go to the arboretum in the southern suburb.我们可以去南郊的植物园。
• The arboretum is full of exotic flowers and rare herbs.植物园里长满了各种奇花异草。