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New Technique for Creating Nanotube Sheets
Quetzalcoatl writes "A team of researchers has come up with a way to make strong, stable sheets of multiwall nanotubes at a rate of seven meters per minute. These sheets already display a number of remarkable qualities that lend them to many different applications, including artificial muscles, transparent antennas, video displays and solar cells."
No Flash Photography of the nanotubes please.
They will explode.Two Roommates and a Boyfriend, updates Monday, Wednesday, and Friday
"2000 posts pointing out how this is a dupe. :/"
Amusingly, nobody checks to see if a comment on it being a dupe already exists before they rush to the reply button.
"Derp de derp."
PBS Nova is offering online playback of a really neat series called Science Now.
The second episode included a neat profie of researcher Naomi Halas who studies nanoshells -- spheres rather than tubes. One potential appication is as a treatment for cancer.
Here's what I do: Bitty Browser & Andromeda
Is the softball-sized device in the video really the entire manufacturing "factory"? What's the feedstock, and how is power supplied?
Imagine a gang of ribbon robots (ribbots?) in Solar orbit, each with a tank of feedstock. They roll their ribbons out from a central equipment cluster towards a circumference 10Km away. The whole rig is spinning, the "centrifugal force" keeping the ribbons straight towards the circular rim. Pairs of magnetically linked ribbots literally weave ribbons around the ribbon spokes, just like spiders weaving their webs, welding paths around the center to the spokes. Now there's a 300Km^2 circle, weighing 10tons collecting 4TW of uninterrupted solar energy.
Even if this film is only a little better at photoelectrics than current PVs, that's over 1TW, the entire US electrical consumption. Put two up there, mount a soviet-style maser array (98% efficiency) pointed at a relay platform floating out in the Pacific. We can recycle all our power plants, coal mines, and petroleum "allies" into national parks or shopping malls (I know which one I'd convert the nuke plants to).
If we float the "PowerWeb" in Solar orbit closer to the Sun, we don't even need as large an area: halfway to the Sun gets 4x the power, over 5KW:m^2. OTOH, since the material is so strong, light (and maybe cheap), we can make them really big, without worrying too much about shear and ripple forces tearing the web. If we put a couple dozen of them floating around the Solar System, maybe in some concentric rings vertical to the ecliptic, we could install a power grid for exploration and colonization of our entire Solar System. A "light rail" capturing Solar energy, and beaming it against a fleet of solar sails, shuttling crews and cargo around. All at the speed of the original Age of Sail, except a few weeks could get us around from Earth thru Neptune - mere days for unmanned craft at >1G.
And this is just the first generation of the tech. Both the material and the factory will get smaller, lighter, cheaper, better. I just hope the American vision of scientific exploration proves worthy of the promise of this stuff. Because I'd hate to switch paying my power bills from Saudi Oil to Chinese Electric.
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make install -not war
These sheets have about 14T nanotubes per m^2, or lines of 4M tubes per meter - thats a 250nm "process" of nanotubes. If each tube can be made a pixel (maybe tagging it with an organic group, for OLED), that's 100K dpi. And likely not on a perfect rectangular "grid" like today's 25dpi LCD monitors, but rather in an "organic" texture like the surfaces of actual objects we see. 10Gpixels per square inch - where are my VR contact lenses?
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make install -not war
Maybe a premature announcement to get additional funding for a project that's still decades away from seeing results, I dunno... but something about this just screams "cold fusion" to me, and I don't think we'll ever see it.
File under 'M' for 'Manic ranting'
In that case, wouldn't it make more sense to find some way to bring the still-popular story back to the top, instead of presenting the same thing as new news twice?
qntm.org
Even if this film is only a little better at photoelectrics than current PVs, that's over 1TW, the entire US electrical consumption. Put two up there, mount a soviet-style maser array (98% efficiency) pointed at a relay platform floating out in the Pacific.
... or Beijing ... or wherever ....
I admire your vision. But I'm afraid that orbital maser arrays will more likely be pointed at Riyadh
-kgj
-kgj
Score 5? Oh, give me a break!
:P
The problem with the foam is that Nasa loves to leave the shuttle outside for days with an unstable foam (suspectable from sun hardening/creating cracks, soaking up moisture from the atmosphere which then freezes, widening the cracks).
There have been no studies that indicate that the few days that the main tank spends outside the vehicle assembly building have any effect at all on the foam's stability. Quite to the contrary, the evidence suggests that it's the method of application - especially hand-application - that determines its stability.
The temperature difference between outside and inside of the foam can reach about 100Kelvin.
Only after it has been fuelled. Also, it depends where on the surface you're talking about - the difference between inside the LH tank and outside can be as much as 300K, but the temperatures on the skin vary incredibly widely.
If they would shield it from the sun
You want them to build a *Second* VAB? Do you want the shuttle to blow it to shreds, or do you want this *second* VAB to be more complex than the first, and retract in its entirity? Seriously, I thought slashdotters thought the program spent too much money being overcautious where it didn't matter already.
do not drive it out to early
They drive it out as physically late as possible - not for some mythical sun-foam problem, but because of the risk of storm and wind damage. Launching a 2,040,000 kg craft safely takes days on the pad. It takes hours just to fill up the tanks. The crawler takes 5-6 hours simply to get to its destination 4 miles away. Etc.
and keep it nicely aircoed and conditioned,
Ah, there you go! That'll be an economical choice for a nonexistant problem - a retractable, insulated air conditioning building on top of the pad.
If really good aircoed, or with more accurate launch windows, the foam might not bee needed at all.
False. You would need *zero* percent humidity as well. And a redesign at that - the foam insulates against heat as well. It's not a realistic proposal, as you'll notice that it hasn't been done anywhere in the world.
The tank will never gets really hot (it is dumped before that happens, and then burns itself on the way down, nobody cares about that part of the trip)
Do you know why the ET is orange? It's not because they think it's a pretty color. The SOFI (Spray On Foam Insulation) used on the shuttle is a variety of materials known as SLAs (pronounced "slaw") - SuperLight Ablator; orange is its natural color. I assume that you know what an ablator is. They use an ablator precisely because there is so much heat during the trip - don't tell me that you thought that something with such a huge cross section, moving at high speeds, and with irregular protuberances and with close proximity to engines wasn't going to get highly heated
Last but not least: this problem is a problem invented by Nasa. The foam would not or be less necessary if Nasa used a different fuel (kerosine like the Russians)
False. First off, the Russians have worked with LOX/LH a good bit, mainly on upper stages - when not solid, kerosene stages are almost always lower stages (with a few exceptions). Want examples of stages/craft either developed or studied? Angara KVRB, Energia core, Energia EUS, Energia M, Interim Hotol, N1 Block R, N1 Block S, N1 Block SR, N1 Block VII, N1 Block V-III, Proton KM-4, UR-700M-3, Vulkan-1, Vulkan Blok V.
Heck, even the Kliper is considering a LOX/LH2 upper stage - such a stage was proposed back in 1962 (Molniya 8K78L) for Soyuz. It'll need one to get the sort of performance numbers they're claming. The bottom stages will remain kerosene.
Secondly, the ET and SSMEs are not the equivalent of the Russian (lower) kerosene stages - the SRBs are the equivalent of the kerosene stages (near Earth thrust to lift and accelerate the craft). The main tank fu
Are there any deer in the theater tonight? Get 'em up against the wall.