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It appears there is a full-specifics article in Science, but I don't have access to it. However, someone on Liftport does, and posted an excerpt:
Especially considering the absence of polymer binder, the mechanical properties of the aerogel-like and densified MWNT sheets are unexpectedly high, which is probably a consequence of the interconnected fibril network (fig. S2). The density-normalized mechanical strength is much more accurately determined than mechanical strength, because the sheet thickness is less reliably measured than the ratio of maximum force to mass-per-length in the stretch direction. Stacks of undensified sheets have an observed tensile strength of between 120 and 144 MPa/(g/cm3) (fig. S5, A and B). A densified stack containing 18 identically oriented sheets had a strength of 465 MPa/(g/cm3), which decreased to 175 MPa/(g/cm3) when neighboring sheets in the stack were orthogonally oriented to make a densified biaxial structure. These density-normalized strengths are already comparable to or greater than the ~160 MPa/(g/cm3) strength of the Mylar and Kapton films used for ultralight air vehicles and proposed for use in solar sails for space applications (21) and those for ultra–high-strength steel [~125 MPa/(g/cm3)] and aluminum alloy [~250 MPa/(g/cm3)] sheets.
Sheets generally have much lower limiting strengths than do fibers of the same material. However, at a value of 465 MPa/(g/cm3), the tensile strength of the densified MWNT sheet is comparable to or exceeds reported values for nanotube fibers and yarns that do not include a binding agent: 575 MPa/(g/cm3) for forest-spun twisted MWNT yarns (12), 500 MPa/(g/cm3) for aerogel-spun yarns (7), 105 MPa/(g/cm3) for SWNT yarns spun from superacids (22), and 65 MPa/(g/cm3) for SWNT yarns spun using an acidic coagulation bath (23). Order-of-magnitude or greater increases in mechanical strength have been observed when internanotube coupling is enhanced by polymer incorporation into nanotube sheets and yarns (23–26), and similar strength increases might be achievable by infiltration of suitable polymers into the present MWNT sheets.
There's also some discussion that at present, the nanotubes in the buckytape appear to be adhering only by Van der Waals forces between neighboring nanotubes.
So, to summarize that for my less technical readers: As stands, without any kind of resin binder, the buckytape appears to be around four times as strong, weight-for-weight, as ultra-high-strength steels, and adding an appropriate polymer binder might increase that to as much as forty times as strong.
There's also some speculation in that Liftport thread that starting with longer buckytubes may yield a proportional or near-proportional increase in tensile strength, something I have speculated on myself. If so, then assuming one could find the correct binder and triple the length of the individual nanotubes, 100 times the tensile strength (weight-for-weight) of the strongest steels currently known ought to be within reach.
Oh yeah, glossary: SWNT = single-walled nanotube, MWNT = multiple-walled nanotube (concentric buckytubes, essentially), MPa = megapascal. One megapascal is approximately 145 pounds per square inch, or approximately 10.44 tons per square foot, so 465MPa/(g/cm3) would mean that, to pick simple numbers, a buckytape cable a foot square with the density of steel (7.8 grams per cubic centimeter, about 4.5 ounces per cubic inch) could support on the order of 39,000 tons. As discussed above, using the correct binder and doubling the nanotube length might increase that to as much as 800,000 tons.
(It should be noted that this density is somewhat improbably high for a carbon cable, but it makes an easily-visualized comparison.)
Update:
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rbos has graciously provided a link to a PDF copy of the Science article.
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-Ogre
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-Ogre
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The Nature article also mentions applications like electrically-heated windshields, since the fil is transparent and electrically conductive, and as conductor elements for roll-up flat-sheet TVs.
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Cool.
-Ogre
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My concerns are more related to how you keep the tent ventilated enough to avoid smog and CO2 building up to intolerable levels. I also find myself speculating on greenhouse effect. There's plenty of places where I can see it might be a good idea to build a tented city, but about the only one on Earth I can think of offhand is Antarctica.
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Having lived in London during a Christmas smog (one timed perfectly to keep fallout in had the Cuban Missile Crisis gone hot), I agree that containing smog within a city is not a good idea.
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-Ogre
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Next you'll be saying you don't like the idea of sandmen chasing down runners who didn't turn themselves into renewal.
Oh. Wait. I'm older than that too.
Yeah, bad idea. very bad idea. :-)
Seriously, though, controlling the weather inside cities through transparent domes/tents seems like it would have some positive impacts. And then there's the whole 9/11 thing. What down-sides do you see?
Plus, that japanese pyramid structure seems a lot more plausible this way. I also wonder about the new concrete filler that they're using, that uses small threads of some material instead of rebar, for its structure. I wonder if you could take that to the next level with thin strips of this tape. That might help with building a strong enough foundation for that pyramid (which, IIRC, was a bigger problem than building the actual pyramid).
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Next you'll be saying you don't like the idea of sandmen chasing down runners who didn't turn themselves into renewal.
*grin*
Seriously, though, controlling the weather inside cities through transparent domes/tents seems like it would have some positive impacts. And then there's the whole 9/11 thing. What down-sides do you see?
Well, see the previous note about trapped pollution, air exchange, and greenhouse effect, for starters.
It also means any city that wanted a tent and had airports within the city would have to close them and build new ones outside the tent. (It might be possible to build "airlocks" for seaports, but I have severe doubts about it being actually feasible.)
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I'm not terribly worried about trapper air pollution/etc. You've got to suspend the tent on something, and that can have air processing and ventilation units.
In fact, it could make a great way to do a solar tower: the tower holds up the tent, and at the top of the tower is a turbine that extracts kinetic energy from the air that wants to rise out of the top of the tent. (and, even if this material wont help with building the structure of a beanstalk, it might help with building the structure of a solar tower)
And, because the air is trapped, you can actually do more with it, not less, in terms of dealing with air pollution. Depending upon how you segment the tent, you could move the air artificially, and those movement points could involve air filtration to remove nasty things from the air.
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Of course, if we pollute the atmosphere badly enough, we might end up not having a choice....
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Here's a copy of the article:
http://novylen.net/~rbos/gi9gs0p5.pdf
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I am SO building my Cozy with this stuff, if I can possibly afford it. This will not only lower my empty weight, but make a stronger aircraft into the bargain.... alas, my gross weight is limited by the strength of my landing gear, but still, if that saves me 150lbs on a 1050lb airframe, that's another 2.5 hours of fuel - at high cruise - on the Deltahawk
warp driveaerodiesel mill.... actually, they make propellors called Warp Drive... but I think I'm going to go with the German-made MT 3-bladed composite reversing prop, since that will make it much easier to take a hot ship like a Cozy into a short strip.... with the constant speed prop getting power out for takeoff isn't a problem, but you're still landing at 75mph or so, and even 3-puck MATCO brakes don't help if it's a grass strip; the grass will simply rip loose and hydroplane the aircraft (grass-o-plane?) but reverse thrust doesn't depend on the tires holding. An important consideration on rain-slicked Pacific NorthWet runways. And with a single engine asymetric thrust is a moot point.But I digress. I hope they make props out of this stuff too; composite props are notoriously delicate and subject to gravel or hail strikes ruining a pretty prop.... and metal is heavy and they don't make affordable reversible props of it.
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Also, google "Cozy kit aircraft".
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in about 500 years the wheel and the buckyball are going to be culturally synonymous