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Two years ago if you had asked anybody on the streets of Beijing
what a "nanometer" was, the answer would most likely be,
"I don't know, but where can I buy it?"
This joke, which has been circulating amongst Beijing's scientists,
who have been doing nano-structure research for some time, lies
in the identical pronunciation of "meter" and "rice"
in Chinese.
The joke reflects the public's general ignorance of nano-technology,
as it stood before"nano frenzy" swept the country two
years ago.
Nanotechnology refers to technologies and related research applied
to the minute space between one nanometer and 100 nanometers, when
one nanometer is one thousand-millionths of a meter. In simple terms
it is the technology that deals with the manipulation of individual
atoms and molecules. Research into this space hopes to be able to
create devices that are able to manipulate matter atom by atom.
For example, scientists envision nano chips replacing microchips,
which would exponentially improve the calculation speed of computers.
And nano robots with a size of 100 nanometers can be produced to
help doctors do surgery in the innermost corners of human body if
technological breakthroughs in this regard are made.
A more easily digestible description of the technology's significance
is that with it man will be able to "turn stone into gold,"
although that day may still be far off.
The idea of nanotechnology may not be new, but even so it had not
been given serious consideration by scientists internationally until
the beginning of the last decade of the 20th century when a number
of breakthroughs in the area were made.
Like other scientific research, nanotechnology, once imported from
abroad, triggered a frenzy across research disciplines first, before
eventually spilling over into the media.
Almost all of the major universities in China and the research institutes
under the Chinese Academy of Sciences (CAS) jumped on the bandwagon,
touching on almost all aspects related to nanotechnological research.
While outstanding achievements were being made in labs, confusing
information about products, allegedly manufactured with "nanotechnology,"
also began to appear on the market.
Nano-washing machines, nano-paint and nano-textiles appeared one
after another on the market this year, confusing customers.
In the middle of this year, a famous brand washing machine put their
so-called "nano-washing machine," on the market, it later
turned out to be a joke.
The stock market was also affected by the new term when several
listed companies, reportedly investing in nanotechnology research,
saw their stock prices shoot up.
The media began to take an interest as well and came up with stories
in this regard, some of which were true and serious while others
were simply confusing.
When asked to comment on the frenzy, some scientists showed only
tolerance, saying the hype encouraged the people's and even the
government's interest in nanotechnology. "That's good for researchers
to get the necessary aid," said a scientist engaged in nano
chemistry research that declined to be identified.
It was not only the general public that caught "nano-fever,"
the scientific community found themselves infected as well.
In China's scientific community, nanotechnology is used in a broader
sense rather than the more specific "molecular nanotechnology"
that refers to technology used in manipulating matter on an atomic
level.
Nanotechnology in China also refers to the making of nano-material,
materials produced with nanotechnology that demonstrate special
physical and chemical properties more suitable for industrial use
than ordinary ones and research into the physical and chemical properties
of matter within nano space.
For example, scientists have produced a nano-material called carbon
nanotubes in labs which is 100 times harder than steel but only
one-sixth its weight.
Theoretic calculation shows that it is the only material people
know so far that would not snap under its own weight if rolled out
to the length of the distance between the Earth and the Moon.
It will be a very ideal material to replace steel if we find ways
to manufacture it on an industrial basis.
When it comes to the making of nano-material, the definition is
easily blurred.
So far, a handful of nano-material making methods, invented by Chinese
technologists, have been granted patents by the State Bureau of
Patents.
Most of them are for the making of nano-powders such as fine silicon
powders, which are reported to be finer than 100 nanometers and
demonstrate properties different from those of ordinary silicon
powder. "They may not necessarily be made using 'nanotechnology,'
but you cannot say they are wrong if they label it 'nano-powder,'"
said Wan Lijun, a research fellow with the Institute of Chemistry
under CAS.
Behind the nano boom is a hasty mentality to show obvious success
as soon as possible.
For example, a nanometer titanium powder was reported to be produced
by "using specific technology" in Harbin, Northeast China's
Heilongjiang Province, recently.
A news article, run in the Science Times Daily, called the technology
the "first in the world."
It also quoted Xie Sishen, one of China's leading scientist in this
area, as recognizing the invention as an example of putting nano-technology
to industrial use while most other countries are still working exclusively
in the lab.
Ironically, the newspaper also once ran an article lampooning the
so-called "pseudo-nano" phenomena.
In spite of the frenzy, a handful of Chinese scientists have made
serious progress in areas of basic research into nanotechnology,
or within the arena of "molecular nano-technology."
Research in this arena should be based on three accepted principles:
1: Getting every atom in its right place.
2: Making almost any structure consistent with the laws of physics
and chemistry so that we can specify their atomic detail.
3: Ensure manufacturing costs do not greatly exceed the cost of
necessary raw materials and energy.
Chinese scientists' achievements have mainly been related to research
into carbon nano-tubes, the most promising nanotechnological research
so far.
Carbon nanotubes are structures that consist of grapheme cylinders
closed at either end with caps containing pentagonal rings.
They were discovered in 1991 by Japanese electron microscopist Sumio
Iijima, who was studying material deposited on cathodes during the
arc-evaporation synthesis of fullerenes.
He found that the central core of the cathodic deposit contained
a variety of closed graphitic structures including nanopar-ticles
and nanotubes, of a type which had never previously been observed.
A short time later, Thomas Ebbesen and Pulickel Ajayan, from Iijima's
lab, showed how nanotubes could be produced in bulk quantities by
varying the arc-evaporation conditions.
This paved the way for an explosion of research into the physical
and chemical properties of carbon nanotubes in laboratories all
over the world.
China's research in this area also produced a series of outstanding
results, especially last year.
A research team led by Cheng Huiming, of the Institute of Metal
Research under CAS, produced single-walled carbon nanotubes that
can store and release hydrogen in significant quantities at room
temperature. These nanotubes are also reusable, which is an exciting
step towards making hydrogen energy available for daily use some
day.
Another team led by Xie Sishen, of the Institute of Physics under
CAS, this year synthesized carbon nanotubes with diameters of 0.5
nanometers, the thinnest academically recognized particle so far,
using an anode filled with carbon nanotubes and using the arc discharge
technique. The nanotubes are in the form of the inner-most tube
of multi-walled nanotubes.
It verified the theoretical presumption that the thinnest nanotubes
is likely to be between 0.4-0.6 nanometers in diameters.
Other than research into making ideal nano-materials, a team from
the Electronics Department of Peking University has made headway
in manipulating single-walled carbon nanotubes, making them "stand"
on the surface of another metal, a gold membrane for example. This
breakthrough came last year.
Prior to that, scientists could only obtain single-walled carbon
nanotubes that "sleep" on a metal membrane, which prevents
them from distinguishing the physical properties of the nanotubes
from the interference of the metals.
Meanwhile, they made the best AFM (Atomic Force Microscopy) probe,
one the most important tools in nano technological research, in
the world with the nanotubes.
All these achievements, significant in academic terms, further scientist's
understanding of matter in nano space and improve their capability
to manipulate it.
But any dream that scientists produce something overnight that might
come to be used in everyday life is unrealistic, the scientist warned.
To promote China's research in this arena, several major high-tech
projects in China have increased their aid to important research
bodies.
And the CAS announced the establishment of a Nanotechnology Research
Center at the beginning of this month.
Known as an "aircraft carrier" for China's nanotechnology,
the center is expected to build a partnership of several major research
teams under it.
Although China's research in a couple of key areas is breaking ground
internationally, insiders confess that there is still some distance
between China and other leading countries in several other research
arenas, the most critical of which is processing technology. "Nanotechnology
is not a science, it is a technology, or more precisely, a processing
technology, " an insider named Xiong Zhi wrote recently in
an article posted on a Nanotechnology BBS. "New scientific
discoveries, if any, are by-products of this process."
He noted that China's most pressing need is to build its own processing
capability and develop the necessary equipment, such as lithographs
and laser projectors.
"Even though we have made some discoveries, without a processing
capability, it is still merely a stepping stone for others,"
he noted. "Only when our own processing system is constructed
will we be able to compete with the United States and Japan in this
area on an equal footing, and see new scientific discoveries flow
freely."
(China Daily 11/29/2000)
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