Posted on 12/12/2006 10:06:16 AM PST by blam
DNA-like ice 'seen' inside carbon nanotubes
14:15 12 December 2006
NewScientist.com news service
Tom Simonite
Spectacular ice helix structures form when water molecules are squeezed into carbon nanotubes under high pressure, in computer simulations (Images: Xiao Cheng Zeng)
Nanoscale ice formations resembling the double helices of DNA will form when water molecules are frozen inside carbon nanotubes, detailed computer simulations suggest.
Researchers at the University of Nebraska, US, used a supercomputer to run detailed mathematical models of the behaviour of water molecules. In their simulations, they inserted the molecules into carbon nanotubes under high pressure, before cooling them to -23°C.
The scientists were surprised to see the molecules organise themselves into "spiral staircase" arrangements similar to those of a DNA helix. "It was very unexpected," Xiao Cheng Zeng, the computational nanotechnology expert who led the research told New Scientist. "We had expected ice to form into tube structures that have been observed before inside carbon nanotubes."
The simulations involved modelling the behaviour of water molecules packed inside nanotubes measuring between 1.35 and 1.9 nanometres in diameter, under pressures of 10 to 40,000 atmospheres. The combination of such a confined environment and such extreme pressures distorted the hydrogen bonds within each water molecule in ways never seen before, Zeng says.
(Excerpt) Read more at newscientisttech.com ...
Makes sense to me. Carbon nanotubes are one of the most 'perfect' man made objects ever. It isn't that surprising that something as 'natural' as water might, when all variables taken away, settle into something as common and 'natural' looking as something found in the very existence of life.
--when all variables taken away--
"under pressures of 10 to 40,000 atmospheres."
Look sorta like galaxies.
"before cooling them to -23°C."
Is this Ice-9?
-when all variables taken away--
"under pressures of 10 to 40,000 atmospheres."
"before cooling them to -23°C."
Piece of cake.... :)
These names come from R. Buckminter Fuller who made an impressive career out of pointing out how sensible and predictable the design patterns of Universe happen to be. Whether a spiral galaxy or a DNA helix, there are some geometrical relationships which are repeated in ways which are surprising (and not so surprising).
The big red, orange and blue dots are the oxygen atoms. The little dots are the hydrogens.
Just not sure why they used three colors for Oxygen.
Under conditions pertaining some 3.5 billion years ago --early pre-Cambrian-- miles-high glaciers covered drifting portions of what became Gondwanaland, the primordial super-continent that plate tectonics split to form contemporary land-mass distributions.
As continental glaciers ground together, temperatures of -23C plus pressures approaching 60,000 PSI might well have been quite common, and obtained for geological epochs (approximately 10.0 million years). In such circumstances, protracted over some 2.0 billion years, who is to say what Nature might produce by way of helically-structured nanotubes? Not only that... consider that such 3-D patterned freezing would lock organic components in place, where sooner or later such nano-molecular architecture would tend naturally to reproduce.
If computer simulations have reached this (surprising) point, let's do some cellular-automating to explore whether such "commonly occurring" structures might indeed have grown and changed-- i.e., evolved. Then move from hard-drive to test-tube, i.e. to biological reality. A mathematical basis for structural organic entities subject to evolutionary development would probably be the single most significant discovery in scientific history.
Darwin would be proud, disciples of Allah would hone their chainsaws. Forward!
I think the best approach to this is to create the critters then start plugging in DNA segments (genes) found among viruses in the ocean.
See what they do.
Might be some of them create organic based intergalactic space cruisers, or possibly time machines ~ whatever you want could already be out there.
We can get around to the "evolution" stuff later on.
Fascinating.
bump for later reading
Yeah, that's cute. Really. Probably not stable worth a damn thing. You can talk on and on about the metastable forms of water, talk with Austen Angell at ASU. That well will never run dry... especially when you put in buckyballs...is there anything we haven't done with them buggers yet? Richard's dream was to make a super-long single fiber...that's the ticket. Not toxic crap and pretty pictures.
Space elevators...perhaps?
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