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Carbon Nanotubes are also purportedly stronger than steel in certain configurations, and have been considered as a sort of "space elevator" mechanism, by which objects could be hoisted into space via a machine that would scale a "rope" suspended by a satellite object.

I'll have to find a reference for that, I'm sure.

Just about all (if not all) conductors have carbon in them. Carbon is conductive. Maybe pure carbon is a better conductor than something else that is part carbon?

Ever heard the term "carbon based"?

I don't directly correlate transfer efficiency to carbon content, but all things in nature can be dated by their carbon content. All things currently known to be in existence (that I'm aware of) are carbon based.

Rocks and rock formations can be carbon dated. Rocks were living at one point?

Carbon dating is just the most famous technique for checking the age of things. It does not have a very long range, geologically speaking.

Winfield, have you considered posting your query to a forum where people would be doing more than guessing?

When's the last time you read anything about it? I haven't seen anything since it was on TV about a year ago.

It can be used up to about 60,000 years, IIRC, before present. "Present", in this case, is considered 1950, as I understand it.

It's often beneficial to understand whether one is actually making guesses, or just being a smart ass.

At the moment, I'm going to say hype. That was the point I was trying to make while being a smart ass. It's a "smoke and mirrors" science for now, because all of 100 people in the world *might* know anything about it, if the technology is anything more than toilet paper with scribbles on it to begin with.

I dunno about the fight, I don't watch fighting since I got out of it years ago.

I've been starting to see carbon nanotubes and carbon "buckyballs" and such as hype, like the flying car. Pretty sure I've been reading little "won't it be cool when.....?" blurbs about these things for at least 20 years. Still don't have any in my hands.

Wake me when they've come to market.

Where do I start with this thread.:eek:
I have worked with carbon nanotubes.

"1000 times MORE CONDUCTIVE than copper and aluminum"
Did you ever think they may have meant thermal conductivity and not electrical conductivity.
If you want to increase electrical conductivity you go for superconductors.

Yes, the carbon nanotubes themselves are way stronger than steel.
But, to make the "space elevator", more a thin ribbon than a "rope" they are used in a binding matrix.
Much like glass fibers are used in a polymer matrix for fiber glass.
The weak point is the binding matrix.
At the present time we can not make a macro-scale nanotube that would be composed of only nanotube structured carbon.

Just to widen the discussion carbon isn't the only element to form nanotubes.
Also related check out graphene.

Uh, No!

Electrical conductivity is a the ability of am element or compound to permit the free movement of electrons through it.
Where as a insulator is just the opposite.

What about metal carbides?
They can have high carbon contents, but are insulators.
It is the chemical structure that permits or restricts both electrical and thermal conductivity not the carbon content.
What about metals in general, no carbon there!
What about Magnesium Diborane (MgB2)?

Wow, ever hear of the term crack, as in what are you smoking?

Carbon based means that it structure is based in carbon and its chemical properties. Like "carbon based life", not that non-carbon based life has been found yet.

Uh, once again NO!
Radiocarbon(C14) dating is good for once living material and only back 60,000 years, or so.
Maybe a little further with very sensitive isotope separation via a accelerator.

What do you think coals radiocarbon content is?
Given that it can be over 280 million years old and the half-life of C14 is approx 5,700 years?

There are other radioactive elements used to date things that are inorganic and/or older than the current radiocarbon limit.
Check out U/Pb, K/Ar, or U/Th dating techniques.
How do you think the Earth's age was determined to be 3.8 Billion years old.
So far as I know no living organisms or there remains have been detected from this period, so how did they date the rock via C14?

Next time, please read all the posts in the thread. You can move on after you've realized that not one of those posts was serious.

So you know someone using nanotubes for moding their vehicle for increased FE?

I don't have an issue with the discussion so much as the lack of understanding you have shown for basic science, let alone advanced material science.

I highly recommend you join other forums, just to read and understand the science behind the technology you you seem to think is hyped.
Nano-technology holds many promises, some which we will reap quickly, some of which many never come to fruition.

check these out:

SciCentral: Physics & Chemistry News

PhysOrg.com - Science News, Technology, Physics, Nanotechnology, Space Science, Earth Science, Medicine

And don't be afraid of Wikipedia when you don't understand something.
Guessing about the workings of technology when you have access to the internet is just plain stupid.

Oddly enough I did, and I see no evidence that in fact your posts were not serious.
I did seriously debate posting, thinking why should I dissuade you of your notions on how things work.
My concern wasn't for you, but for some one else who may have stumbled across this and taken those notions as facts.

[edit]
Actually, it looks like you did make reference to being a "smartass" this morning, and I read this thread to it's then completion last night.
I started a reply and just didn't have the time to complete it till this evening.

Thank god, my apologies!

Electrical conductance of a SWNT have had actual measure measurements of electron density of 10EE7 A-cm2 with indications of the ability (theoretical?) to exceed 10EE13 A-cm2(way more than 1,000 times that of Cu).

Thermal conduction(measured at a specific temp, 100 degrees K) approaches nearly 40,000 W/m-K (again, way more than Cu)

These are actual measurements, but are on isolated (sometimes individual tubes) laboratory prepared samples. Production of bulk material with these values is unlikely.
Unless a new fabrication technology is developed, of which there are many under development.

Didn't need to check Wiki, as I know both thermal and electrical conduction of specific type (sub-classes) of these materials have very high conductivity. Typically, high thermal conduction in these materials preclude high electrical conduction and vice versa.
Many times the conductivity of these materials is anisotropic and these values are only seen along the axis of the tube, not across it.

So with the general term "conductive" used and no reference provided how did you know electrical conduction was meant?

I don't see how that could possibly be. If you look at e.g. line losses in electric power transmission over copper wires, they run about 10%, so even a perfect conductor could only improve by that 10%.

Also see here for recent news about nanotubes made from materials other than carbon: Better Nanotubes May Be on the Way -- Fox 2009 (1210): 3 -- ScienceNOW

Yeah, fell into the same trap when I first started working with these.
It's the difference between conductance vs conductivity:
Electrical conductance - Wikipedia, the free encyclopedia
Electrical conductivity - Wikipedia, the free encyclopedia

This is the best explanation without all the vector and tensor equations making things more complicated than they need to.
Everyone reports current densities of 1000x Cu, or even higher for carbon nanotubes.
But if conductivity is equal to current density over electric field strength one must assume that the electric field strength in Cu and Carbon nanotubes is the same.
I would have thought with a 1000x higher current density that the electric field strength would be higher and thus would reduce the ratio.
Wouldn't be the first time I was wrong!
Might well rest with those previously mention vector and tensor equations.
One consequence of this is that a cabon nanotube can be 1/1,000, in theory, the cross section (or less) of an equivalent Cu cable carrying the same amount of current.


Good link!
Also, other on going work have used both "buckyballs" and nanotubes (carbon and other compositions) as cages to hold other elements and compounds.
These materials exhibit such promising characteristics as super-conduction, helium traps, and fission fuel containment and moderation.

So if thats the case, what do you think of superconductors?

Most reported results do not correspond to 20 deg C, though that value maybe in the data, there is no requirement that a value be given at that temp.
It does appear that the conductivity of carbon nanotubes varies greatly with temperature, far more than Cu conductivities.
Once again understanding the difference between conductance vs conductivity.

Who was bickering?
How about you post the link to the article and we can see the "error".


What do you mean "realworld variable" and "normal variables"?
You ever have an MRI, know what the Large Hardon Collider is, use electricity(superconducting power cable and generator windings are in use) as there are super conducting wire used in these applications.
High temp superconductors are advancing and now can be cooled with liquid nitrogen. Much much cheaper than liquid helium.
The target is room temp. super conduction or higher.
This like nanotubes is about understanding the science behind the phenomenon and then modifing the structure, process, material to get the results we want.




Please provide data/link on Ag being 1000x more conductive than Cu.

These are still early days for nanotubes we don't have a full understand of why they behave the way they do, same with the high temp superconductors.
I'll bet you didn't think you'd have a personal computer with the power you now have at your finger tips 20 yrs ago either.
I'll bet, for what that's worth, that in 20 yrs way more than 1% of the world population will have nanotube based technology in use in their homes/work.
Not so sure about the high temp super conductors, but the cost barrier will be lowered to the point that people will exposed to direct applications using the technology even if they don't have it as part of their home.
All of this will be pushed harder because it going to be more effective and efficient to conserve energy than to build more power plants this techology may come faster if only for that reason.