Re: [Sci.nanotech] Carbon Games


On a dark an' dismal Tue, 01 Apr 2008 21:31:11 -0500, in flickering lamplight,
"Perry E. Metzger"
<perry@xxxxxxxxxxxx> scribed with phoenix qill :

Well.
I know i said fire away, but i wasn't expecting
a flame. The moderators are usually careful
about that....

mike <mikespam@xxxxxxxxxxxxxxxxxxxxxxxxx> writes:
So, i was musing on carbon tubes. Specifically
how to make a nice yard or more, single length tube.

I presume you mean a "single wall carbon nanotube".

Yes, that's what i meant.

How to coax the carbon to take our choice over its own?
I'm not clear what you mean by that.

Only that left to itself the carbon will just sit, doing its
own thing.

In my head, almost fully outlined popped this:
A tiny chamber filled with carbon dioxide, kept active
via laser to stop it settling on the walls.

I'm not clear what you mean by that, either. A gas like CO2 doesn't
"settle on walls" at normal temperatures, at least not generally
speaking. (There are circumstances in which some CO2 could be adsorbed
into surfaces, of course, but that's clearly not what you have in mind
here.) I'm also not sure what "kept active via laser" would mean.

Right, first, i don't really know where the carbon dioxide slipped into
the text. Sorry for that, was intended to be all carbon.
The other things like 'normal temp' you refer to?
It's hot, that's what the laser's for, to 'keep it active' a gas.

A silicon partition with six laser made perforations
(single carbon atom sized) in a hexagon pattern.

A carbon atom is order of magnitude the same size as a silicon
atom. To make a "perforation" this size in a silicon surface would
imply somehow removing individual silicon atoms with a laser.

Which i have read has been done. [might not be silicon, though]

Since an >individual atom is on the order of 100pm (one angstrom) across, you
would need a laser with a wavelength on that order of that length.
<<#>>

As i understand it, the trick is to use two or more lasers at half strength,
creating rings like a ripple in a pond. Where the rings intersect they add,
and have the effect of lifting away individual atoms present.
I think this was detailed in 'New Scientist' [might not tho], unfortunately
not in the copy i have to hand.
I'm sure it's been talked about here before though, does anyone recall it?

<<#>>
Besides, it isn't clear you could even get the Si atoms to
reliably absorb the x-rays -- they'd likely pass through the surface
instead.)

Okay, what would you suggest?

Even assuming you could somehow remove single Si atoms by this utterly
impractical means, you could not drill a single atom wide hole through
an Si surface -- the Si atoms would just migrate and close your hole
up.

They would move that fast? I thought we would have them vibrate
and eventually seal the holes, but i was assuming months.

And a pressure control between the two, so that when
the holes are filled the difference encourages it to
progress through to the ordered side.

I have no idea what this means, or what relationship it might have to
your mention of CO2 gas or your "hexagonal pattern" "perforations".

To colour it in a little, all it meant was keep the feed side at a slightly
higher pressure, thus encouraging the carbon trapped in the holes to
move through.

I hypothesize that you somehow think that CO2 could somehow be forced
up to the magic holes you imagine you drill, the carbon atoms would

Apart from the dioxide muck up in my first post, for which i have
already apologised and will not keep doing so, 'coax' is the word i
used because i knew 'forced' was inappropriate.
The Carbon atoms will eventually enter them, if energy is
supplied when things wind down.
[Don't call them magic holes again, please.]

somehow magically detach from their bound oxygens, that following this
the carbon would somehow not instantly bond to the Si,

Let them, Next time the laser passes over they will be released.
Or don't use Silicon, another reason it's a bad choice.
What do you suggest as an alternative?

and that somehow by forcing streams of C atoms out the "other side" in a
hexagonal pattern they'd somehow magically form a "nanotube". (Why a
hexagonal pattern? Perhaps you've seen a sketch of a graphene *** in
a magazine and fixated on the hexagons.)

Why not a hexagon? It had to be something, and that just dropped it place.
Do you have a specific reason it cannot be one?
All that's important is providing the carbon with plenty of opportunity to
bind in some stable ring formation, and still be open to linking to more from
the feed side.

This idea is more or less as plausible as the notion that you could
make humans by forcing bits of homogenized cow through a short slot in
a piece of *** steel.

This doesn't relate, in any way. I am talking about atoms, and that
'notion' above, as you call it is not.

Perhaps my hypothesis on what you mean is wrong, but I can't think of
any mechanism by which a "hexagonal pattern" of "perforations" in some
Si is going to make you a SWCNT.

You have missed the point and focused on trivia.
Right at the start was the warning that this was unpolished thoughts,
and i was posting to spark off some feedback.

I guess this won't work like this, maybe the carbon
will behave better in a liquid mixture?

What do you imagine a "liquid mixture" of "carbon" means? Do you think
that somehow if you can make "carbon" into a "liquid" that it will
work better in your nano-scale pastry decorating tube?

It means exactly what was said, a mixture, not a compound, that
forms a liquid.
How you extrapolated to get that i don't want to know.

(For reference, you can't actually make carbon into a liquid anyway --
at least, not at temperatures below 4000 kelvin and very high
pressures.)

I'm glad i didn't suggest it then :-)

Perhaps you imagine using liquid CO2 would be better for your purpose
than gaseous CO2 -- the answer is no, it won't.

You imagined that, not me.

It makes no difference what phase the cow homogenate is in
when you throw it at a small slot in some *** steel --
you still won't get a person extruded.

Pity, i'm sure they'd be very nice people.
[please drop this, it's not even an analogy.]

Anyhow, I'm still interested in why it won't work :-)
Fire away. :-)

It won't work because none of it makes any sense at all.

Yet you still responded to it?
It is a suggestion to build nano tubes from carbon gas, by
letting it bond only in set points.

It isn't even a proposal

It wasn't pretending to be one.

-- it is a series of odd and not particularly plausible
ideas with no connection between them, none of which seem to have
anything to do with carbon nanotubes. I had to guess at what you were
talking about and even then it was completely implausible.

Yet you replied at length to something that made no sense to you.
there was a reason for the first paragraph, and the subject heading.

----------------------------------------------------------------------
(As an aside, I'm rather disappointed in the moderators for letting
"Mike"'s message through.

Perhaps the assumption is that since there are no postings these days,
absolutely anything, no matter how strange, should be
forwarded.

Or perhaps as i have posted here many times, the moderators
know i wouldn't post senseless rubbish, and would respond to requests
for clarification.
Or maybe it did make sense to them.
You might want to ask them.

However, my suspicion is that no good content is posted precisely
because the bizarre content has driven serious people completely
away. (Were it not for the date on the original message, I would have
assumed it was an April 1st prank.)

Personally i think pranks are juvenile, and have nothing to do with them.

Of course, it appears to be too late for sci.nanotech since the
content is now approximately one post of this last post's quality per
month, but perhaps a lesson can be drawn for other future fora.)

I suggest that you re-read the beginning of my original post and
then decide if that was justified.
Still, not too bad considering you didn't understand it.

mike.

.