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Nanodoubts from Canada
Those who have already read the articles about nanotechnology presented in this section and in other publications will have little surprise. Even so, it´s always useful to present the subject one more time, through an article published this month on the National Post Online, a Canadian journal, written by Margaret Munro. The name is "Science New Frontiers: Small Miracles". Since K. Eric Drexler presented his book "Nanosystems: Molecular Machinery, Manufacturing, and Computation" in 1992, the scientist´s community is on a turmoil of creativity. The book established the field of nanotechnology, and Marvin Minsky said about it: "Devices enormously smaller than before will remodel engineering, chemistry, medicine, and computer technology. How can we understand machines that are so small? ´Nanosystems` covers it all: power and strenght, friction and wear, thermal noise and quantum uncertainty. This is the book for starting the next century of engineering". Margaret Munro says that most of it remains stuff of fiction, but there is clearly a revolution afoot, and Robert Wolkow, a research officer at the National Research Council in Ottawa and one the leading nanotechnologists says that many really remarkable things willl happen, but they´re not going to happen next year or even in five years. A more realistic time frame is 10 to 20 years before nanotechnology dramatically changes our lives. But some projects have already come to fruition, says Munro. "Computer data storage has been dramatically improved through nanotechnology. Minuscule nanodots are being used as markers in biological experiments. Nano-sized zinc oxide particles that do not scatter light now make sunscreen transparent. A team at the National Research Council lab in Montreal has improved the physical properties of some polymers by 50% by adding nano-sized bits of clay". It seems the most remarkable advance of nanotechnology is in carbon nanotubes, which measure less than 1/10,000th the width of a human hair. Meyya Meyyapan, director of the Centre for Nanotechnolgy at NASA´s Ames Research Center in Moffet Field says that they are 100 times stronger than steel but only weigh about one-sixths as much. So nanotubes could generate lightweight, super-efficient computers, cars, planes and spacecraft. But production is slow for the moment, and scientists can only generate nanotubes at the rate of about 100 grams a day. Meyyapan also comments that nanotubes could also help bridge the gap between the living world and computers. At NASA, scientists are gluing biosensitive proteins to detect disease on the end of nanotubes, and remarks that it is like trying to stick a water droplet onto the tip of a pin balanced on a table top. Nanodoubts are related to the suggestions of Drexler about self-replicating nanomachines, or assemblers. This raises the spectre of out-of-control nanobots going on rampage, consuming everything in their path and generating what has been described as "gray goo". But many scientists of the field say that Drexler is dreaming. Nobel prize Richard Smalley of Rice University says that "self-replicating mechanical nanorobots are simply not possible in our world". Wolkow says that self-assemblers are pure science fiction. He even goes on to say that people who believe nanobots are going to replicate "are nuts". After describing many devices and techniques that are being tested and could be expected for a near future, reporting enthusiastic statements of scientists, Munro ends her article with a note of disbelief: "Lofty goals. Lots of talk. And a long way to go". Related news:
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