Nanotechnology #3

Anders Sandberg (nv91-asa@nada.kth.se)
Wed, 18 Jun 1997 16:40:29 +0200 (MET DST)


I just looked through Volume 8, Number 3 (the September Issue; I like
accelerated publication). The site is
http://www.iop.org/EJ/3/99/bin/toc/na08003/ (unfortunately only for
paying customers). If you can access it, the mpeg animations from the
first and last article mentioned below are very fun.

Some fun stuff: the NASA article about molecular gears (Molecular
dynamics simulations of carbon nanotube-based gears, by Jie Han, Al
Globus, Richard Jaffe and Glenn Deardorff), which suggests that
nanogears will work up to 600-1000 K and rotation rates less than 100
GHz. Sounds good to me, although the animations looked a bit rubbery.

"On the importance of quantum mechanics for nanotechnology" by Noid,
Tuzun and Sumpter was a bit more worrying, they claim that classical
molecular dynamical studies of nanosystems may give inaccurate
answers, and that quantum simulations may be needed (they propose
their ICQMC model to deal with this). I'm not sure about how powerful
their critique is, but they seem to suggest that some qualitative
results may not hold due to quantum effects; low frequency modes may
be more troubling than previously thought.

Finally, "Dynamics of He/C60 flow inside carbon nanotubes" by Tuzun,
Noid, Sumpter and Merkle has some fun simulations of fullerenes
carried through nanotubes using helium. Seems the tubes can work as
pipes too.

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