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By Mario Ritter
Broadcast: July 29, 2003
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VOICE ONE:
I'm Bob Doughty with Phoebe Zimmermann, and this is the VOA Special English program, SCIENCE IN THE NEWS.
VOICE TWO:
This week -- a special report on nanotechnology. It appears to be the next great area of scientific discovery.
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VOICE ONE:
Nanotechnology gets its name from a measure of distance. A nanometer, or nano, is one-thousand-millionth of a meter. This is the level of size of 1)atoms and 2)molecules. Nanotechnologists work with materials this small.
Some experts credit the idea to physicist Richard Feynman. In nineteen-fifty-nine, this Nobel Prize winner gave a speech. He called it “There's Plenty of Room at the Bottom.” Mister Feynman discussed the theory that scientists could make devices smaller and smaller -- all the way down to the atomic level.
He did not use the word nanotechnology, but for years this idea remained only a theory.
VOICE TWO:
At the time, no way existed to record structures the size of molecules. Not even electron microscopes could do the job. But as the nineteen-eighties began, two researchers found a way. Gerd Binnig and Heinrich Rohrer worked at a laboratory in Zurich Switzerland. They worked for I-B-M, the American company International Business Machines.
They invented what they called a scanning tunneling 3)microscope. This permitted scientist to observe molecules and even atoms in greater detail than ever before.
VOICE ONE:
Once they could see microscopic structures, the next step for scientists was to find a way to create their own.
By the middle of the nineteen-eighties, scientists had increased their research on carbon. They were interested in the ability to use this common element to make nano-sized structures. Carbon had already been engineered in chemical reactions to make long 4)polycarbonite chains. Today, the result of carbon chemical engineering is everywhere -- in the form of plastic.
Scientists in the eighties wanted to create nano structures from carbon atoms. In nineteen-eighty-five, Robert Curl, Harold Kroto and Richard Smalley succeeded. They aimed a laser at carbon. This powerful light caused some of the carbon to become a gas.
The scientists cooled the gas to an extremely low temperature. Then they looked at the carbon material that remained. They found, among several kinds of carbon, a molecule of sixty atoms -- carbon sixty.
VOICE TWO:
Carbon sixty is a group of tightly connected carbon atoms that form a ball. It is a very strong structure. This is because all the atoms share any loose 5)electrons that might take part in chemical reactions with other atoms. This kind of molecular carbon can also appear with different numbers of carbon atoms. There is also carbon seventy, for example.
Research has shown that carbon nano-structures even happen in nature. Scientist have found carbon sixty and carbon seventy structures in rock.
These kinds of molecular structures had been unknown to science. For their work, Robert Curl, Harold Kroto and Richard Smalley received the Nobel Prize in Chemistry in nineteen-ninety-six.
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VOICE ONE:
The next nano-structure developed came in nineteen-ninety-three. Japanese scientist Sumio Iijima of the N-E-C company developed carbon nanotubes. These nano-sized objects are really six-sided atomic structures connected to form a tube. They are extremely strong. Scientists believe that someday nanotubes could replace the carbon graphite now used to make airplane parts.
Soon after this discovery, researchers started to think about using nanotubes to build extremely small devices.
On May first of this year I-B-M announced that it had made the world's smallest light. Researchers used a carbon nanotube attached to a silicon base. They sent electrical charges down the tube. The reaction between the particles produces an extremely small amount of light. I-B-M says the 6)wavelength produced could be used in communications.
VOICE TWO:
Nanotubes are not the only form of nanotechnology. Scientists are studying many different materials. The British magazine the Economist reported that a company has developed a special kind of cloth using nanotechnology. This cloth made by Gorix is treated with gasses under heat. This process gives the cloth the ability to carry electricity like metal.
The military is interested in such technology. Some researchers hope to develop what they call “smart cloth." Such cloth could transmit signals, record information or even change color.
Clothing makers have already found civilian uses for cloth made with nanotechnology. Their kind of material has the ability to resist dirt and always look freshly pressed.
VOICE ONE:
Common products can be improved with nanotechnology. The sports equipment company Wilson has developed a new tennis ball using nano-science. The inside of the ball is covered with a thin layer of an extremely fine substance. A special clay with nano-sized particles makes the ball last longer and perform better. Today, the ball is used for the Davis Cup tennis competition.
Indeed, the possibilities of nanotechnology appear endless. Some researchers hope to create nano-sized devices that will enter the body to fight disease or replace lost body parts. Engineers hope nanotechnology will help industry make materials atom by atom. They also hope to use nano-stuctures to create materials that are lighter and stronger than ever before.
In electronics, we have already seen the work of nanotechnology. In two-thousand, the American company Intel announced that it had created a transistor only thirty nanometers in size. Transistors are small devices that control the flow of electrical current.
As if this was not small enough, I-B-M announced that its scientists had created an even smaller transistor -- only four to eight nanometers thick. Experts say this kind of technology will permit computers in the future to store much larger amounts of information.
Nanotechnologists have also been at work to develop brighter flat screens for such things as computers and wireless telephones.
VOICE TWO:
However, scientific claims can sometimes move faster than the science behind them. In November of two-thousand-one, a scientist claimed to have created the smallest transistor yet. Jan Hendrik Schon (yahn HEN-drick shern) said it was the width of one molecule. He and his team worked for Lucent Technologies at its Bell Laboratories in New Jersey.
The company later ordered on investigation. The investigation found that some of the research came from earlier studies. It also found there was little evidence that the scientist developed what he had claimed.
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VOICE ONE:
Not everyone agrees that nanotechnology is a good idea. Bill Joy is chief scientist at Sun Microsystems in California. He says he fears that nanotechnology will be used for the war against terrorism. He says he believes it will be possible to develop microscopic robots that can build copies of themselves -- just like living creatures. He says such robots might change the balance of life on Earth.
Such a danger as Bill Joy imagines has already caught the interest of writers and moviemakers. There's a new movie called "Prey," based on a book by Michael Crichton, that could help influence what some people think of nanotechnology.
But supporters believe the current research will lead to great discoveries. Nobel Prize winner Richard Smalley is one of them. He says he believes that people like Bill Joy are simply wrong. At the same time, there are also efforts to establish new centers to study the possible side effects of nanotechnology. There is concern, for example, about sicknesses in factory workers who may breathe extremely small particles.
VOICE TWO:
One thing is clear. Nanotechnology is receiving more financial support than ever.
In two-thousand-one, the administration of President Bill Clinton spent about two-hundred-eighty million dollars as part of the National Nanotechnology Initiative. For this year the Bush administration asked for more than seven-hundred-million dollars. The United States faces strong competition from the European Union and Japan.
Clearly there are big expectations for this science of the very small.
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VOICE ONE:
SCIENCE IN THE NEWS was written by Mario Ritter and produced by Cynthia Kirk. This is Bob Doughty.
VOICE ONE:
And this is Phoebe Zimmermann. Join us again next week for more news about science in Special English on the Voice of America.
注释：
1) atom [5AtEm] n.原子
2) molecule [5mClikju:l] n.（化）分子
3) microscope [5maikrEskEup] n.显微镜
4) polycarbonite [7pCli5kB:bEnait]n.（化）聚硝酸甘油
5) electron [i5lektrRn] n.电子
6) wavelength [5weivleNW] n.（物）波长 |