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The World's Longest Carbon Nanotube
Roland Piquepaille writes "As you probably know, carbon nanotubes have very interesting mechanical, electrical and optical properties. The problem, currently, is that they're too small (relatively speaking) to be of much use. Now, researchers at the University of Cincinnati (UC) have developed a process to build extremely long aligned carbon nanotube arrays. They've been able to produce 18-mm-long carbon nanotubes which might be spun into nanofibers. Such electrically conductive fibers could one day replace copper wires. The researchers say their nanofibers could be used for applications such as nanomedicine, aerospace and electronics."
So perhaps the internet will indeed become a series of tubes?
Voila! No more global warming!
8-)}
"Extremely long"?
Perhaps 18 mm stands for... 18 million miles?
Nano nano nano.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
I love it when a story has a happy ending.
18mm? Can be spun together into longer fibers? Get me to space.
What's worse, your flamebaiting or your lack of a sense of humor?
;)
Obviously, your flamebaiting. Good call.
Did I get it right in the subject line? Apparently all Slashdotters are supposed to hate this Roland guy, right? God, I just want so desperately to be loved...
3,2,1
Yay for buckyballs!
Praise His Noodliness. RAmen.
(eom)
at 18mm It's gunna take a lot of these to make a space elevator
Anything with the word "nano" in it is automatically cool. I'm hungry for a nanosandwich and some nanofries, with a nanoCoke to wash it down. The preceding sentence was very cool.
There's no place like ~.
Can these "nanofibers" be used to make a space elevator ribbon? Or does that system require a different method of employing carbon nanotubes?
Apart from more tubes for the interwebs, I would imagine that 18mm is also long enough to make carbon fibre products that are lighter and stronger than what is currently available. I wonder if an America's Cup or F1 winner will one day be built from nanotubes?
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
...could one day replace copper wires. I can see where this would be bad for home wiring."DAMN!
18 millimetres? Great, only 99,999.999982 km to go!
When our name is on the back of your car, we're behind you all the way!
... do you think they could be compensating for something?
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
In other news, Bjorn Stevens, world's tallest midget, and jumbo shrimp decry military intelligence in Iraq peace action.
-l
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If a condition must be met before a fibre can be spun into a thread of infinite length, it should be the length-over-thickness ratio of the fibre, not its length. You cannot turn 18mm sided cubes into a thread, but nanotubes, being super thin, require less length. It's like doing the same thing at a smaller scale (imagine shrinking your wool-making equipment).
Now we're going to get spam advertising ways to lengthen our nanotubes...
will be when someone figures out how to either join these fibres together, or grow a continuous nano-scale monofilament.
Then we will really see what Arthur C was talking about.
The applications for "diamond" fibre are enormous.
Trying to associate Microsoft with "fun" is like trying to associate Satan with aromatherapy. -Tycho
Although the PR person who wrote this obviously thinks this is a major breakthrough, these guys are using a method which was originally invented by Japanese researchers three years ago (google for "CNT super growth"). The Japanese guys have since focused on getting the fastest growth rate possible (I think it's about 0.2mm/min... if you want to figure out how many, many years it would take to grow a space elevator). There are lots of people working on improving this growth method, 18mm arrays may be the longest, but it seems to be in the same range as other people working on the "super growth" method. That doesn't diminish this research, rather it means that this method is very likely to work in the long run for industrial scale growth of nanotubes for materials (more simply, it's easily reproducible, and people want "nano-enhanced" golf clubs).
Isolated nanotubes have been grown longer than this (I've grown isolated nanotubes longer than this, and I'm not a growth specialist), as have bundles of nanotubes. This is the longest array of pure, aligned, continuous nanotubes.
This is not the record for longest tube ever grown. Groups have grown single tubes the size of their substrate wafers (4 inches usually). This group grew a long bundle of CNTs. In the field we call these 'forests'--imagine a lawn, but at the nanoscale. The blades of grass are the CNTs poking up off the surface.
Remember also that the figure of merit of a CNT when used for its mechanical properties is the growth defect density per meter, and even for the best growth techniques so far this ends up being a number like 1 every 10 microns (10^-6 m).
This means that for something such as a macroscopic cord, not only would one have to grow incredibly long CNTs, they would also have to be nearly defect-free in order to satisfy the (nearly magical) strength requirements attributed to them by many people.
here [tinyurl.com] is a photo, face hidden of course.
pwned
Is the word 'carbon' enough to be classified as 'biotech'? Is a pencil 'biotech' now?
It would be nice if people actually read up the subject before posting this garbage...
This is not "The World's Longest Carbon Nanotubes." It's the longest mass-producable parallel carbon nanotubes.
"Dictator Flakes. They WILL be delicious."
H. J. Simpson
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
It's a relative term - extremely long compared to their diameter. These are about a million times longer than they are wide.
Here's what I remember from last time...
To be held up, a space elevator needs a FABRIC with a tensile strength of about 65GPa.
To build it, you'd want a safety factor of about two, thereby a tensile strength of about 120-130GPa.
I do not know the specs of the tubes from TFA, however
Very short INDIVIDUAL single-walled carbon nanotubes have been created (in a lab, in small quantities, using processes that may be prohibitively expensive) with measured individual fiber strength of about 60GPA.
"Very long" ones were (previously) created at about 1cm with substantially lower tensile strength (circa 4GPA if memory serves me right).
The last several years were spent by industry leaders in this field ramping up production of CNI by several orders of magnitude, whereas bulk availability made prices of CNI go down orders of magnitude.
Existing processes of weaving tubes into a fabric involve loading the fabric with ~5+% of CNI. The last Elevator2010 competition saw competition tethers in the 4GPA ballpark (using fibers in the 30-60GPa ballpark I'm guessing), none of which could beat the commercially-available "house tether".
This is all layman talk of an enthusiast, not a professional. I'm a coder/syadmin gone biochem, not an engineer. If someone a bit less clueless than me can correct and/or bring this up to date (some of what I recited here I've acquired ~3 years ago, things would have progressed since then), I think we'd all be the wiser.
Cheers.
-
Made in USA?
or Nanotubes made in CHINA?
This makes the space elevator closer to reality by enabling practical manufacturing. Lowering the bar to access to space to under ten dollars a pound delivered freight to twenty thousand mile standard orbit will allow also the building within most lifetimes of a real space station with real artificial gravity. More than that, this station can be the template for a base of opertions for exploration of our whole solar system by men and not just machines. First the local by solar electric, and later the outer areas by nuclear. We could even build roving exploration system ships with self contained systems and their own artificial gravity as well, large ones with self contained power and hydroponics for food growing that could self support themselves in deep space. Such could mine local bodies for critical minerals. Could even get helium three for fusion fuel.
While this advance shows good progress and will be very useful, it should be noted that this is still good old-fashioned bulk materials processing, and not molecular nanotechnology (MNT).
18mm long nanofibres aren't going to help us bootstrap our nanoscale toolkits, which we need to do before we can get anywhere remotely close to constructing complex MNT devices.
And this highlights the current problem in MNT research --- all the big money is going into the traditional bulk processing of nanoscale materials, because the materials and chemical industries are well acquainted with those, and can see huge profits in them just around the corner.
In contrast, MNT is an utterly foreign concept to them, and indeed can be expected to be highly disruptive to their current business models by putting the means of production into the hands of those without billion-dollar chem plants.
It's all a bit sad, but expected, in this world of vested interests.
Back when lasers were still new, it was really big in sci fi (such as James Bond and Star Trek), as a magical tool with near universal applications and can safe (or destroy) lives.
Nowadays, lasers are. They're used in everyday objects like CD players, to complex medical procedures like laser eye surgery and those machines that kill otherwise inoperable brain tumours.
I have a feeling that carbon nanotubes will too.
- RG>
Hey pal, this isn't a pleasantforest, so don't waste my time with pleasantries!
Can't you have a pulley system with two cars - one goes down when the other goes up. That would reduce energy costs to practically zero. All you need to do is fill the one at the top with atmospheric water and it would pull the other car up as it descends.
No sig today...
Luckily, yester-year's super gee-whiz invention "The Laser" will do the job nicely.
Can't wait to get a pair of laser-snips.
rhY
I hold very few opinions. I hold information based on observation and fact. If you wish to disagree, please use facts.
It's all about having a cable going from a place with lots of space and lots of sunlight down to where that power is needed.
IMHO a space tether will mainly solve our energy problem, cheap access to space is only a by-product...
But nuclear wouldn't be half bad idea for solving the power supply issue for the space elevator, it's just a matter of resiliant packaging made to withstand the most absurd failure mode that someone could dream up. A small nuke turbogen reactor or battery actually makes more sense than trying to beam energy up to the thing, not to mention the Navy and NASA folks have proven designs for either.
As for the rocket folks, think of the places rockets could go if that fuel wasn't wasted getting out of earth orbit. Those things could be more useful if starting out from orbit.
And the way I picture the thing, the space elevator isn't the best descriptor beyond the prototype. I like the skyhook term better for the production model, and picture something akin to a shipyard gantry crane. It'd have a minimal operating crew (function is better suited to cargo than people), take about a month to get from earth to orbit, feature at least two escape pods (cheap surplus soyuz bolted on?), and would be configured so that it could latch onto existing cargo containers for shipment to orbit. Should be made to load in a straight forward fashion from a truck or cargo ship. A lot more cost effective in other ways, as payload prep would be a lot less involved and could use existing shipping containers.
Nanometers wide, millimeters long. Isnt that an aspect ratio approaching a million?