From: Harvey Newstrom (mail@HarveyNewstrom.com)
Date: Tue Jul 16 2002 - 08:00:14 MDT
<http://www.nytimes.com/2002/07/16/science/physical/16NANO.html?todaysheadlines>
The New York Times has an article on the state-of-the-art of nanotubes.
The longest one produced is eight inches in the laboratory.
However, they note that they are currently not as strong as other
artificial fibers. I assume this is because of defects and that the
theoretical nanotube is much stronger. They also note that IBM's
nanotube transistors are not any better nor any smaller than
silicon-based ones. They also haven't been able to figure out how to
mass produce them yet. Again, I assume this is due to a poor
proof-of-concept model. The article also said that IBM has not figured
out a way to mass produced these semiconductors.
Other developments do seem to be real and less vaporware. SI Diamond
Technology of Austin, Tex. SI Diamond has developed nanotube displays
for lighted billboards like those in Times Square, but at a quarter of
the cost of L.E.D.'s. Samsung of Korea has also latched onto this idea
and plans to begin selling large flat-panel televisions that are lighted
by thin layers of nanotubes in late 2003.
Nanotubes are still very hard to make. They come in mismatched shapes
with no good way to make them of univorm diameter or chirality.
Purified batches of nanotubes cost about $250,000 a pound.
Even though their atomic structure is well-known, and one would expect
their properties to be predictable, scientists are still having
surprises with their nanotubes. A batch of nanotubes caught fire at
Rensselaer when somebody took a picture of it. The nanotubes are so
taut that they converted the light into heat energy, spread it almost
instantly, and ignited the carbon itself. This could produce some nasty
surprises if nanotube-based sructures turn out to be explosive under
bright light! Rice University in Texas discovered that nanotubes not
only absorb specific light spectrums, but that they also emit infrared.
Everyone has expected nanotubes to be inert, and nobody expected them to
give off infrared light.
These properties seem related to the taut structure of nanotubes which
conducts heat (vibrations) really well. They allow liquids to be kept
uniformly molten, and might allow solid structures to resists uneven
heating and cooling.
-- Harvey Newstrom, CISSP <www.HarveyNewstrom.com> Principal Security Consultant <www.Newstaff.com>
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