
Graphene: The Wonder Substance - ColinWright
http://richannel.org/graphene-the-wonder-substance
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elteto
I am not very familiar with graphene but I would like to know how well it
scales up from the molecular/nano scale to the macroscopic. I took a
Material's Engineering class in college and I remember the professor saying
that the "theoretical" strength of materials (in general) was supposed to be
extremely high, orders of magnitude higher than what you find in real life.
The disparity is a result of imperfections in the crystal lattices of the
materials. You can probably build a graphene tube 50nm in length and find that
at _that_ scale it has all those superior properties, especially since at that
size you are almost handling molecules _individually_ and can arrange them
correctly. But what happens when you go up in the scale? Will it retain all of
those wonderful properties to the same extent?

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tcpekin
Graphene is simply a single layer of carbon atoms. If you roll one up, voila,
you have a carbon nanotube you've been hearing about for the past 10 years.
Carbon nanotubes (CNTs) have similar properties as graphene (act as a metal or
a semiconductor, are the "strongest materials known, etc.[1]).

From what I understand, it is very difficult to make large sections of pure
graphene or long CNTs. As long as they're pure, they remain strong, and
therein lies the difficulty of graphene and CNT production. Like you said, the
impurities do weaken CNTs and graphene. The impurities can be contaminants
which occupy a carbon location, or missing carbon atoms, forcing the lattice
to reconstruct. According to [1], this can lower the tensile strength of a
carbon nanotube by up to 85%. The problem with manufacturing long CNTs and
large areas of graphene is that it is thermodynamically impossible to, on a
large scale, have a perfect lattice. The imperfections will weaken the entire
structure. So yes, as you go up in scale, the incredible/fantastic properties
will just become impressive.

[1] <http://en.wikipedia.org/wiki/Carbon_nanotube>

*I currently study materials science and can produce literature upon request. Also this is from the top of my head so it may contain some errors.

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DanielBMarkham
This post looks suspiciously light on content.

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septerr
Off topic - But what does the Ri in these type of animations stand for?

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ColinWright
The Royal Institution of Great Britain. I've spoken in the Faraday Lecture
Theatre, and will be doing so again tomorrow, Saturday, and next Friday. It's
a fabulous place with an amazing history and ongoing present.

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septerr
Thanks!

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studio625
C'mon space elevators!!!

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walru
I'd be happy with a pair of heated long johns.

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stcredzero
<http://lmgtfy.com/?q=heated+underwear>

<http://www.toast-clothes.com/>

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hobbyist
Can some one tell me which softwares are used to make such a presentation? It
was quite a neat work :-)

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superchink
It was put together by these guys: <http://simpleshow.com/>

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soofy
Future Applications of Graphene: <http://www.youtube.com/watch?v=-YbS-YyvCl4>

