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Research / Pre-Cursor Technologies / Molecular nanolayer binds copper and silica up to 700 deg C
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on: May 19, 2007, 08:11:39 PM
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Link: http://www.physorg.com/news98540556.htmlBecause of their small size, these enhanced nanolayers will likely be useful as adhesives in a wide assortment of micro- and nanoelectronic devices where thicker adhesive layers just won’t fit.
Another unprecedented aspect of Ramanath’s discovery is that the sandwiched nanolayers continue to strengthen up to temperatures as high as 700 degrees Celsius. The ability of these adhesive nanolayers to withstand and grow stronger with heat could have novel industrial uses, such as holding paint on hot surfaces like the inside of a jet engine or a huge power plant turbine.
Along with nanoscale and high heat situations, Ramanath is confident the new nanoglue will have other unforeseen uses. |
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Research / The LiftPort / Re: Sky station
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on: March 07, 2007, 02:48:50 AM
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A station at 20-30km would be more worthwhile than one at 5miles. NASA currently switches stages at much higher than 5 miles, so, if multi-stage is desirable, I don't think human tolerations would be a limitation. my 2¢.
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Research / Pre-Cursor Technologies / Re: CNT chain
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on: March 07, 2007, 02:25:50 AM
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The 100,000,000,000,000 rings per square centimetre assume that the links are circular, they could be a long but thin ellipse. Say same width but a millimetre long. There is plenty of room for a lot of possible research and development in this area. Hmm. In that case, you'd be looking at 1,000,000,000 rings per square cm* and I think something like 50,000km2 for the entire ribbon. *edit: Actually more than that. That would be a single sheet of rings, invisible to the naked eye and easily tearable. The maximum tensile strength of CNT cables is fixed by the width of individual tubes, the rings link at an area about the same size as the tube radius. The actual strength of the rings needs measuring. I'm not entirely sure. I think you'd want the average, vertical(ish) bond strength per total mass to be as large as possible. I don't think width or cross section size matters at all except in contact with the climber or safety against debri. Is that right? |
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Research / Alternate SE System Designs / Re: Rotating (bolo) Space Elevator
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on: March 05, 2007, 03:07:18 AM
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Would it be more useful to put a rotovator in an elliptical orbit than in circular LEO? I think an elliptical orbit rotovator could be cheaper to construct (lower stress requirements), but would be more complicated to operate, although perhaps more interesting. I think it would be interesting to compare the Δv required for getting payloads to different locations (LEO, GEO, polar orbit, the moon) for rotovators in various orbits.
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22
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Research / Pre-Cursor Technologies / Re: CNT chain
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on: March 05, 2007, 02:24:10 AM
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That would be a real pain to put together. At 100nm raidus, I think it would be more than 100,000,000,000,000 rings per square centimeter of ribbon (hard to say cause the rings would stretch). That's why most people talk about ribbon construction on a macro scale rather than a micro scale (spinning threads into string, etc).
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Achieving the Space Elevator / Science & Technology / Carbon nanotube conductive?
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on: December 02, 2006, 08:43:03 PM
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A research group has devised a way to control the diameter of a carbon nanotube. [Source] As the diameter dwindled, Yuzvinsky and his collaborators were careful to adjust the current through nanotube to account for its increasing electrical resistance. This yielded a surprising and important secondary result of their work: that the conductance of a multi-walled carbon nanotube is directly proportional to its diameter. This clears up many conflicting studies of electrical conduction in nanotubes. |
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Achieving the Space Elevator / Science & Technology / The Space Elevator Developement - A Personal Opinion
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on: November 14, 2006, 09:45:41 PM
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Personally, I am convinced that *eventually* the space elevator idea will be successfully implemented, however it seems absurd to me that it could ever happen until after we have much better capability for making objects one atom at a time (well OK, it would be many parallel one-atom-at-a-time tools). Nope. Way too slow. Manufacture and repair has to be done on the macro scale. Multiple SEs require lots of ribbon and repair has to be expedient. Quality control can be nano scale. It does make sense that we should understand the technology for the climbers, and have solid ideas about the mechanics of deploying the ribbons, and other details, but until we can manufacture and repair the ribbons, we won't have an elevator. Correct. More people should be testing climbers on balloon tethers right now. |
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Achieving the Space Elevator / Law & Politics / Obtaining permission to launch a manned capsule
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on: November 11, 2006, 09:24:26 PM
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Yes they are. The FAA has extensive regulations for radio towers and such, and LiftPort's work on tethered balloon has involved quite a bit of communication with and permissions from the FAA. Oh yeah. My bad. If the SE were built in, say, Arizona, the FAA regulations would apply, but only as a building, not as a aircraft. I don't think that lauched capsules would be (or should be) inside the FAA's jurisdiction. Administration is important, but not only Federal. |
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Achieving the Space Elevator / Law & Politics / Obtaining permission to launch a manned capsule
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on: November 07, 2006, 03:55:49 AM
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A space elevator is a tall structure. Tall structures are not registered with the FAA. A manned space capsule thrown from the SE does not qualify as an aircraft and so would not need to be registered with the FAA. However, a reentry vehicle would likely need to be registered (as a glider or powered parachute or something). In a few years, the SpaceShipTwos will start making frequent suborbital flights. They will take off in the Mojave Desert and return there without crossing national boundaries. The SpaceShipTwos will travel through national airspace. However, there are no national boundaries on moon and mars trajectories. A business company that builds an SE would be subject to the laws of the country holding it’s business license. That country would want to maintain international trust and would therefore regulate the use of the SE. However, it could very well be that an SE would be built by an international business company ( http://en.wikipedia.org/wiki/International_business_company ). If there ends up being a competition between more than one SE companies, I believe that it would be in the best interest of the consumer to have the actions of those companies regulated. |
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Achieving the Space Elevator / Science & Technology / Rocking Space Elevator
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on: October 30, 2006, 11:57:07 PM
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Mirror area = 1.8 MW / 1.2 kW/m/m = 1,500 square meters If this were a single concave shape, it would be about 44m in diameter (40% the length of a football field). It would probably be best to use seperate mirrors or something that could fold up. |
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Achieving the Space Elevator / Science & Technology / The Oscillating SE
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on: October 25, 2006, 12:16:52 AM
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Here's a good idea for launching the climber the first several kilometers:
1) Put the climber on the ribbon in 'neutral' (no brakes).
2) Raise the climber to about 30km with balloons.
3) Reel down the ribbon as much as tension will allow.
4) Apply the brakes and release balloons.
5) Unreel the ribbon.
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