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Nanotubes Start to Show their Promise
Rei writes "Researchers at the University of Texas at Dallas have developed the highest quality nanotube sheets to date (the team previously set strength records with polymer-nanotube composites). Producable at a rate comparable to commercial wool spinning, the transparent cloth has exceedingly high conductivity, flexibility, has huge surface area to volume ratios, can potentially be made into very effective OLEDs and thin-film photovoltaic cells, and outperforms even our best bulk materials (such as Mylar and Kevlar) at strength normalized to weight. It strongly absorbs microwaves for localized heating (leading to applications in seamless microwave welding of sections and even windshield warming), changes conductivity little over a wide temperature range (very useful in sensors), and is expected to be used in commercial applications very soon. The research should even be expandable to artificial muscles! To head people off, while the exact tensile strength is not listed, it sounds like it is still far from the >100 GPa needed for a space elevator. Anyways, here's to process advancements!"
I'd like to see these sort of things geared up with 'smart' nanotechnology to make 'smart' cords and stuff like that, imagine a highly conductive wire that provided +, - and ground and detangled itself, or melted into a pool and you just pulled cord out of it, all detangled or bent into whatever shape you want.
I'll subscribe to Slashdot when I see a month without a dupe, a typo, or an article the "editors" didn't read.
Oh good. I wonder how much it will cost for a packet of laser printer paper made of this stuff?
I could use something snazzy for my resume.
Democrats or Republicans. They are both taking us to the same place and they are not afraid of us anymore.
And yes, folks, it cures most deceases and will get rid of that bronchitis for you and you can use it to clean your hubcaps.
To head people off, while the exact tensile strength is not listed, it sounds like it is still far from the >100 GPa needed for a space elevator.
Why do they say they're going to enter the material into some space elevator competition at the end of the article then?
http://twitter.com/onion2k
I can soon have a solar powered bulletproof jacket that enhances my strength, protects me from cell phone emissions, and displays DVDs?
Or, from the article, and perhaps of more interest to us:
"flexible computer screens that could be rolled into a sack"
Haven't we been promised this for years? I wanna roll up my computer screen & carry it into my flying car!
...the cost?
I know tfa says that it will be efficient, but does that take the cost into perspective? It's not unusual to hear about a new idea that is totally ground braking in several fields, then the research on the commercial fades out, because they find out that it's too pricey. A lot of products was that way in the beginning. Just look at LCD screens etc.
Well. That being said. This sound awesome, I'd like to see it developed...
Scully: Should we arrest David Copperfield?
Mulder: Yes we should, but not for this.
Yes, it's producable at a certain rate- but what about the cost? Is it economically feasible?
Unfortunate about the space elevator. Looks like the highest we've gone is 63 GPa (http://en.wikipedia.org/wiki/Tensile_strength)
Super, I envision the day where I can replace my tin-foil hat with a nanotube beret.
Height: 38U, Weight: 0 Newtons, Eyes: #0000FF, OS: Gray Matter 1.0 (Alpha)
According to this article, Andrew Barron (Rice University) seems to think we could see this technology used in Formula One racing cars, as early as next season. Although he's probably being a little optimistic, something like a Formula One team would certainly have the sponsors to experiment with tech like this, and develop cheaper manufacturing processes (if possible).
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
Well, the greatest danger to the clean, sterile environment is carbon-based, you know...
Segmentation fault. Ore dumped.
and outperforms even our best bulk materials (such as Mylar and Kevlar) at strength normalized to weight. It strongly absorbs microwaves for localized heating
Should be interesting to see the day when a drug dealer overrides the safety interlock on his microwave and points it at nanotube body armour wearing DEA officials during a bust.
Should bring a new meaning to the phrase "hot tits"
Hmmmmmm..... Deep fried and look like Squirrel.
http://groups.yahoo.com/group/stoptheelevator/
Yeah, I'm going to have a microwave generator going in my car, aiming the the windshield, just to warm it up.
Don't be silly. It'll just use the ambient microwave radiation we're pouring out now for communications. I'm more worried that with the windshield absorbing all the microwaves my coffee will no longer stay warm in the car.
The reason why nanotube composites don't end up being nearly as strong as nanotubes is that nanotubes are very slippery inside of a composite, so once force is applied, it doesn't transfer through the interface and the ultimate tensile strength is primarily determined by the composite.
In this case, when they are weaving fibers together, the weakness in tensile strength will come from the interface between linked nanotubes which will have a tensile strength many orders of magnitude than that of an individual tube.
Why not? We shoot them into our skulls with cell phones.
"OH SHIT, THERE'S A HORSE IN THE HOSPITAL!"
Even in GR, the stress-energy tensor has zero divergence.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
"...and is expected to be used in commercial applications very soon..."
:(
,
Hmmm, hasn't that been the case for the past decade? That's what my inner cynic says, anyway. Just like the fuel cell revolution, not to mention the nuclear fusion revolution.
there should be a revolution any day now...
on that page was the urine powered battery.... Now that could useful. Drink a few beers and power your laptop.
Finally, a pair of underpants that won't wear out!
intr.v. deceased, deceasing, deceases To die. n. The act of dying; death. And disease (d-zz) n. A pathological condition of a body part, an organ, or a system resulting from various causes, such as infection, genetic defect, or environmental stress, and characterized by an identifiable group of signs or symptoms.
Java Oracle Linux Enthusiast
If it strongly absorbs microwaves, I wonder about its potential as a radar-absorbing material for stealth military aircraft, leadfoot driver's cars, etc.
by teasing nanotubes away from one side of a forest and attaching them to a strip of sticky tape
again proof that duct tape can make anything work!
Soon we will have duct tape made out of this nanotubes, after that, who knows or even dares to dream!!!
The Dallas Morning News (19-AUG) has a story on this. Registration is usually required, so text follows . . .
Article URL: http://www.dallasnews.com/sharedcontent/dws/dn/lat estnews/stories/081905dnmetnanosheet.1c9439ac.html
Video URL: http://www.dallasnews.com/s/dws/spe/2005/nanotech/
---------
LITTLE CREATION, BIG STEP
UTD team's chemical ribbons could assist many high-tech dreams
09:01 PM CDT on Thursday, August 18, 2005
By SUE GOETINCK AMBROSE / The Dallas Morning News
Scientists from the University of Texas at Dallas have spun yards of chemical ribbons that are lighter than a feather but stronger than steel a significant advance in the rapidly growing field of nanotechnology.
(Picture: LOUIS DeLUCA/DMN University of Texas at Dallas scientists (from left) Mei Zhang, Sergey Lee, Ali Aliev, Anvar Zakhidov, Shaoli Fang and leader Ray Baughman took part in the research.)
The development could lead to a host of high-tech applications that scientists have dreamed of but haven't had an easy way to create: futuristic clothes that light up, store energy or blunt bullets; car doors that are ultra light, extra strong and double as batteries to store solar energy; flexible, filmy light bulbs that are thinner than a human hair; artificial muscles for robots; and solar sails to propel space vehicles.
A report describing the chemical ribbons, created from tiny carbon tubes barely visible to the human eye, appears in Friday's issue of the journal Science.
"This is a big deal, a real big deal," said James Tour, a chemist at Rice University in Houston, of the new study. "Every paragraph is a gold mine."
The ribbons are created from carbon nanotubes, filaments about one-five-thousandth the width of a human hair. At the atomic level, the nanotubes look like cylinders of chicken wire. Because the nanotubes, like diamonds, are made entirely of carbon, they are extraordinarily strong. They also conduct electricity.
Scientists had known of carbon nanotubes' exceptional properties but had struggled to easily convert them into convenient forms. Last year, the UTD scientists, led by chemist Ray Baughman, had spun the nanotubes into yarn. Other scientists had created small sheets of nanotubes, but their process was cumbersome. DallasNews.com/extra
"The value of this invention is to make it into sheets," said Ned Thomas, a materials scientist at the Institute for Soldier Nanotechnologies at the Massachusetts Institute of Technology in Cambridge. "Clever people will take those sheets and put them into technologies that have yet to be invented."
THE PROCEDURE
Making the ribbons is quite simple, Dr. Baughman said. The UTD scientists started with a "forest" of nanotube trees, about one-third of a millimeter high. Then they stuck a Post-It note to one edge of the forest and gently pulled away. The nanotube trees were drawn out, and as the researchers kept pulling, the trees stuck to each other side by side, forming a long, wispy and transparent sheet.
Sheets more than a meter long, about two inches wide, and less than one-thousandth the width of a human hair thick can be pulled in less than a minute, by hand in the lab, Dr. Baughman said. The process easily could be industrialized, he said.
"There is no limit on how wide they can be," Dr. Baughman said.
The ability to convert carbon nanotubes into such a useful form will be a boon to many small companies trying to use them to create newer or better devices, Dr. Thomas said.
"Nanotechnology needs this," he said. "It's been hyped, and there's been a lot of expectations."
Dr. Baughman, who said the university and a collaborating Australian national lab have
WTF is Strength normalized to weight?
Specific strength is the term they are looking for, second it is normalized to mass, not weight.
Suggest to me someone with little science/engineering background "wrote" the article, and just listed off the interesting stuff they 'heard about nanotubes'
If this stuff is so resilient, NASA should really research a coating of it over the Shuttle tank foam that keeps falling off.
Artifical Intelligience is no match for natural stupidity.
Well, no. That's the whole point. Even if it's serial it can boost you bandwidth per buck a huge lot.
My english is sow-sow. Sowhat?
According to the Science article(subscription required) abstract a stack of 18 sheets had a strength of 465MPa/(g/cm^3) (high strength steel listed as 125 MPa/(g/cm^3)).
They also built an OLED of 500 cd/m^2 with a onset voltage of 2.4V.
Now, that's not to say the GP is right. At the moment, the investment needed would be astronomic, but we don't know how much this will run long term, and a country that already has a space program and regularly launches satellites may find it works out cheaper in the long term to build such a thing, at least, once the price of mass producing materials strong enough to be used in one comes down.
The other response incidentally is largely wrong. One major advantage of an elevator is you can use it to trap the energy of something coming back down. For launching satellites, the elevator may be uneconomic, for more far sighted applications, such as returning materials mined from elsewhere, it will be more than economic. Of course, just as we're a long way from having a practical material to build an elevator from, we're also a long way from mining asteroids.
You are not alone. This is not normal. None of this is normal.
sorry, according to the wikipedia article on tensile strength. there are a great many things stronger than spider webs. among them include glass and kevlar
Umm, surely this must be totally over-simplifying what they -really- do..
Nope. I saw this presented last month at an Air Force program review, and it is exactly what they say. For example, they showed pictures of 1 m long ribbons, where the length was limited by the length of the postdoc's arm who manually pulled the sheets from the nanotube "forest".
"Is there any common direct conversion of chemical energy to mechanical other than the internal combustion engine?"
Yes
Gas turbines.
Rockets.
Ram Jets.
Pulse jets.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
Of course, if you had been part of the effort, it would've happened twice as fast. But you obviously had other priorities, and I'm sure I speak for all of us here when I express my deep appreciation for taking a little of your precious time to share your insight with Slashdot.
Okay it looks like this could be used anywhere that you currently use Carbon Fiber. I can hardly wait.
Super strong light weight helmets.
Homebuilt aircraft.
Bicycles.
It just goes on and on.
The fact it is transparent, conductive, and absorbs microwaves makes me think that we will see a lot of it uses for RAM coatings on ships and aircraft.
I can also see it being used for anti rf wall paper and and windows in secure buildings.
All in all very cool.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
From the article:
... With this method they can produce nanotube sheets at up to seven meters per minute, ...
Assuming the product eventually exceeds 100 GPa, at this rate it would take over 27 years to produce a 100,000 km ribbon in one piece. Since that timescale would be impractical, I figure they should aim for at least a meter per second, which would allow them to do it in a little over three years instead. On the other hand, they could also, for example, set up 30 production lines to work at the current speed, run them all for about a year and then glue the segments together using the extra length for overlap. However, that would add extra volume and make it heavier (remember that the first ribbon has to go up on a rocket).
I am a chemist, I work in the "nanotechnology" field, and I have spent time in Engineering/MS labs making OLEDs, PV cells, and other thin film devices. Many of "us" consider nanotubes to be the only viable "nanotechnology" at the moment because of the fact that they can be used by spraying thin layers, making entangled sheets, or other easy-to-commercialize methods of preparation. As for the hybperbole, I think the fact that you're reading an article on MSNBC should give you a clue : ) If you read the Science article they make essentially none of the claims present in the MSNBC article. In fact all they really claim is a new method for preparing NT sheets that is way better than the current methods used for preparing NT 'paper' (it really looks and feels like paper).
Yes, nanotubes are cool. Yes, they conduct electricity. Yes, they emit white light in an OLED configuration. I'm not 100% sure where they're getting the artificial muscle thing, but from what I've read (from peer reviewed journals) don't hold your breath - but I'm no expert there. What generally happens here is the inventors like to hype their discovery up (in this case a method for preparing better NT sheets) as much as possible, but in "science speak". That is, this "may be used for ___" or "has the potential for ___" and then they rattle off stuff NTs can be used for which gets all mixed up in the in article. In this case NT sheets are nothing new and most of what they're claiming has been done before (IBM even got light out of a single NT, far more impressive if you ask me), but they're doing it better with higher quality NT sheets. When it was discovered that poly(aniline) had great mechanical properties as well as interesting "chemical switching" and conductive properties there were people that were sure it was going to be used in planes, clothes, computers... You name it. Too bad it is deliquescent - D'Oh. I can't remember whether this happened before or after the discovery that poly(acetylene) had a high tensile strength and people were claiming space elevators, lightweight electric motors, etc etc. Too bad it catches fire in air in its conductive form - D'Oh D'Oh.
At the end of the day this is another step towards some real nanotechnology applications, but you're reading about it because the editors at Science decided it was worth publishing. Only in the Science article they include all the references to the past work that made it possible :) Oh, and the microwave thing is neat because the NTs will spark like crazy in your microwave oven. So will graphite, which you can try at home if you like... If you don't know NTs are essentially "rolled up" graphite sheets, so they share a lot of common properties.
Here is the abstract:
So what they did was create sheets
Actually, I wrote my thesis on life experience.
This month's IEEE Spectrum features an article by Bradley Edwards who studied the near-term feasibility of a space elevator under a grant from NASA. His conclusion is that it could be accomplished in as little as 10-15 years and for as "little" as $10B (meaning little enough that there are several individuals on Earth who could fund it privately). Of course, the major technological limitation is the nanotubes. He suggests "spun" nanotubes (like yarn) or nanotube composites (and he contends that if one of these broke near the top, it would not be the end of life as we know it -- it's a ribbon that would loft gently down to Earth and burn up in the atmosphere). He even addresses storms, terrorism and space-borne threates. It's a good article and somewhat technical (written for engineers). His conclusions are quite credible, and probably more informed than your average Slashdot debate.
Today's Sesame Street was brought to you by the number e.
Paragraph two is mostly right anyway.
a tellites/geo-high.html
First one is wrong regarding total payload mass. I'd do math to refute the statement, but it has already been done. http://trs.nis.nasa.gov/archive/00000535/
And yeah, the travel time will likely be few days. So what? You can get to LEO in a matter of hours once everything has been built out and systems put in place to deal with any whiplash effects that jumping off before the steady-state altitude.
And it isn't 50K miles to Geo -- it is about 24K miles. I point this out simply because it seems like you are kind of 'creating data' to put it politely. http://liftoff.msfc.nasa.gov/academy/rocket_sci/s
Finally, advantage of capturing energy: again, completely off base with respect to the current design considerations. It would be a LOT cheaper ( I estimate at least by a factor of ten, but that is just a guess) to take high energy fuel up to the anchor mass (at the end of the tethor), than to design the system to actually allow both up and down capabilities.
And even if you HAVE a down capability, that by no means implies that you can capture the potential energy of a decending object. Recall that it is a 'rope', not a bar. And the rope is already in tension. I can see no solution which would allow you to gather any worthwhile amount of energy. You can't run a current through the elevator, as you would then have a stupendeous amount of magnetic drag thanks to Earths magnetic field. So no electromagnetic regen. Which doesn't matter, as *any* form of draggy braking against the cable just looks like more mass to be lifted from the perspective of the anchor mass.
If it were a solid bar than the shift of mass would do the job on its own, thanks to the whole inertia game. If we used a 'dangling rope' and litterally tied the 'Low end' to a mass, lifted it into space and then dropped it back down, you could also get the energy back, minus drag.
In summary, your entire post strikes me as pure opinion, with no basis in fact. If I am mistaken, I urge you to issue some form of defense. While I commend you for caring, I believe that you do a disservice by attacking something you don't understand, while pretending, or worse assuming, that you do.
Edwards declares two as "preferable", one exclusively up and the other exclusively down, and provides no means for power exchange between them. He also doesn't study down climbers, which have different requirements (braking and dissipating the braking energy, plus different strains on the tether)
There is a big difference between an up-only cable and an up-down cable - up-down allows for easy energy exchange, better utilization of cable bearing strength, and lower capital costs (than two separate cables), but needs to be a small amount larger, is slightly harder to build, and most significantly, requires many launches of small elevators instead of few launches of large elevators for effective power exchange.
To understand why having both up and down utilize the tether better, picture the strains on each part of the tether if you have one starting at the bottom and the other starting at the top. Start the one on the top first - once it has enough acceleration to go without pulling on the tether, start the bottom one. They pass each other at a point less than 0.5g. The one that was at GEO lands on earth braking slowly while the other elevator largely drifts, and once it touches down, the Earth elevator brakes as fast as it wants to and arrives at GEO.
You'll notice that these two elevators could be carrying a full payload, and put little more stress on the tether than just an up-only climber with equivalent payload at any given point.
Adding in more elevators decreases this benefit somewhat (although still keeps minimal strain on the critical bottom part of the tether at any given time - it's easier to reinforce the further up you get, because reinforcements have to be supported all the way back to GEO), but allows for power transfer. With just two elevators at a time, power transfer isn't realistic (unless the tether superconducts or you can afford the mass of thousands-of-miles-long superconductor, the resistance is too great for long distance transmission; furthermore, the battery mass to store energy for several days of power accumulation is not realistic. Storing several hours worth, however, is realistic, as is transferring that much power in a couple minutes time in a "passing zone")
Kneel Before Christ!
- Molded Nylon - 75 MPa
- Plain carbon steel - 450 MPa
- 4130 Cromoly steel - 1110 MPa
- Dupont Kevlar 49 - 3620 MPa
- Carbon Fiber - 4000 MPa (approx)
As you can see, carbon fiber is about 4% as strong as the target, which tells you two things: First, nanotubes kick butt. Second, this elevator is not right around the corner. Sure they're getting good at making individual fibers, but the weave will not carry the same stress as the individual fibers, and we have to find a way to work around that.It sounds like to me they should use this stuff to wrap the foam insulation onto the space shuttle external tank so it won't fall off. Then they can think about using it for space elevators.