China's research into Nano technology has yielded fruitful results for the past decade, of which a substantial part has been patented.

More than 2,400 papers on nano-technology produced by Chinese scientists have been published in academic journals across the world. Some of them have been printed in the world's top scientific journals such as Science and Nature, according to a report titled High Technology Development in China, 2002.

Most of the accomplishments were made in areas of research and development of nano materials, whereas advances in the areas of nano-electronics and nano biological research are still rather meager.

Most of the 300 companies engaged in nano technology in China are concentrating on nano materials.

This is in sharp contrast with research at the forefront of nano technology in the world, which focuses on the research and development of nano-sized machinery and electronics.

The report was published recently by the Chinese Academy of Sciences (CAS) and constitutes one of the three that discuss China's advancement in science and technology in recent years.

The report comprises of reviews by China's top-notch researchers over advances in their respective research areas, with nano technology being one of the key issues.

Nano technology, in general terms, refers to technologies and related research applied in the minute space between a thousand-millionth of a meter to 10-millionth, or 1 nanometer to 100.

Matter demonstrates physical properties unlike both the arenas of basic particles like atoms and the macro arena pertaining to our ordinary world.

By studying these phenomena, scientists hope to produce machinery to manipulate matter atom by atom.

A more vivid description of the technology's significance to the Chinese is perhaps that with it man can realize the magic of "turning stone into gold," although this day is still a long way away.

The idea of nano technology may not be new, but it had not fallen into the category of serious consideration until the early 1990s when a couple of breakthroughs took place in this area.

As far as China is concerned, the idea had not begun to sink in until recent years, either among scientists or in the broader public sphere.

Like other scientific concepts, nano technology, once imported from abroad, triggered frenzy across scientific research communities and eventually spilt over into the media.

"It has been a very upsetting phenomenon because this research has been sort of overblown in China," Bai Chunli, a recognized chemist and vice president of CAS, noted in a review compiled in the report.

Almost all of the major poly-technic universities in China and relative research institutes under CAS engaged in the frenzy, touching almost all the aspects related to nano technology research.

For example, research has been conducted in the micrometer-sized world for decades and mature technology has been available; they need not assume the name of "nano technology" to be popular. Nano technology is a step forward into the innermost of matter, but may feature revolutionary thinking and approaches.

Patent rate indication

By looking into the patent rate of nano technology in China, the report revealed the current situation with regards to research capacity in this area in China.

Sometimes, the patent rate is a more reliable indicator than the number of published papers, experts say, as patented inventions generally have to go through more rigorous challenges during a prescribed time.

It was found that by the end of 2000, a total of 107 patents had been granted by the State Intellectual Property Office (SIPO) to nano technology applications, while another 475 have been given grants.

According to China's patent laws, a patent will not be granted to an invention application until three years after it has been made public by the SIPO; and no challenge of the application should be established by SIPO during the same time for a valid patent to be granted.

The fact that most of the applications accepted by SIPO for nano-technology, or 81 per cent of the total, are now pending grants indicates that there has been a peak time in nano-technology research in previous years, according to the report.

It was found that before 1990, research in this area was rather slow, like in the rest of the world. Applications began to increase from then on following technological breakthroughs in the preparation of nano-sized materials and these peaked in 1997 and 1998.

"This is consistent with the advancement of research in this area in China," said Ma Xiaoguang, an analyst with the Evaluation and Research Centre under CAS. The centre was commissioned to do this review.

Ma ascribed the increase to the rapid growth of investment from diverse sources. "Not only the State, but various research institutions and companies engaged in this area between 1992 and 1996," he said.

Of all the applications, 62 per cent were filed by universities or research institutions, 26 per cent by companies and the rest by individuals. However, in the 100-plus applications filed by foreigners to the SIPO, most are by individuals. "This suggests that universities and research institutes are still the mainstay that drives China's research in this area," he noted.

Most of the applications concern nano materials, taking up 80 per cent of the total, with the rest on nano-electronics and medicine.

There is also substantial progress in some other areas relating to nano technology, the most outstanding of which is about the carbon nanotubes, according to the report.

Carbon nanotubes

Carbon nanotubes are structures which consist of graphitic cylinders closed at either end with caps containing pentagonal rings.

They were discovered in 1991 by the Japanese electron microscopist, Sumio Iijima who was studying the material deposited on the cathode during the arc-evaporation synthesis of fullerenes, a class of closed, hollow carbon compounds.

He found that the central core of the cathodic deposit contained a variety of closed graphitic structures including nano-particles 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 to 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 achievements.

A research team led by Cheng Huiming of the Institute of Metal Research under CAS, produced single-walled carbon nanotubes in the year 2000 that can store and release hydrogen in significant quantities at room temperature. These nanotubes are re-usable, which points to an exciting prospect of making hydrogen energy available for daily use one day.

Another team led by Xie Sishen of the Institute of Physics under CAS, last year synthesized carbon nanotubes with a diameter of 0.5 nanometer, the thinnest academically recognized so far, using an anode filled with carbon nanotubes with the arc discharge approach.

Other than preparing ideal nano materials, a team from the Electronics Department of Peking University made headway in manipulating nano-sized structures, having single-walled carbon nanotubes "stand" on the surface of another metal, a gold membrane, for the first time in the world.

"These achievements demonstrate China's research capacity to the basic areas of nano technology," the report noted.