Re: Spun nanotubes spell breakthrough (fwd)

From: Spudboy100@aol.com
Date: Fri Nov 17 2000 - 11:35:20 MST


Sweet dream are made of these. Order me a dozen.

xli03@emory.edu writes:

<< Subject: Spun nanotubes spell breakthrough
 
                     
    PARIS, Nov 16 (AFP) - French researchers reported Thursday they
 had achieved a breakthrough in making carbon nanotubes, one of the
 most exciting inventions of the past decade, which could open the
 way to manufacturing them as fibres with a host of uses.
    Nanotubes, first invented in 1991, are tubes with a diameter far
 smaller than a human hair, with a carbon structure that makes them
 chemically inert but light, extremely strong and resilient, as well
 as able to conduct heat and electricity.
    They are conventionally created by vaporising graphite rods by
 electric arc in a chamber filled with a gas such as helium or
 hydrogen, and then allowed to cool slowly.
    Scientists from the Paul Pascal Research Centre at the
 University of Bordeaux said they had devised a method to spin
 single-wall nanotubes into "indefinitely long" ribbons and fibres.
    Unlike other carbon fibres, they are extremely flexible and can
 even be knotted without breaking, they reported. Their research is
 published in full in Friday's issue of Science, the US weekly
 journal.
    Ultra-strong fibres of this kind have a wide variety of
 potential applications, from artificial muscles to hydrogen storage
 and flat-screen TVs, the researchers hope.
    The ribbons were created by dispersing raw nanotube soot into a
 surfactant, or detergent, solution.
    That solution was then injected into a flowing steam of polymer
 solution which caused the nanotube material to recondense into a
 mesh. The flow of the solution aligned the mesh into ribbon-like
 fibres.
    On November 2, separate teams from Japan's NEC Corp. and the
 Hong Kong University of Science and Technology reported they had
 created the smallest nanotubes feasible, each narrower than a
 filament of DNA.
    The tubes were just 0.4 nanometres (0.4 billionths of a metre)
 wide.
    Scientists have previous created even smaller tubes, of 0.33
 nanometres. However, these are unstable because structural changes
 at this tiny scale can force carbon to become metallic. >>



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