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#11
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For NASA to hand that off to a college with an initial eleven-million dollar
grant, I'd speculate that they have already confirmed the effect in question... I am thinking they are now working on producing it in sufficient quantities and dimensions to make it applicable to practical use... Indeed, it looks like the length they have in mind will reach space--if so, that monopole will make a good muli-wavelength antenna for ultra-lowfers!!! Perhaps it will be naturally resonant at the Shuman frequency and Earth itself will begin to CQ DX! grin Regards, John |
#12
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One more thing, when you start swinging a wire around in a magnetic
field--you begin to generate a current and voltage/power... although the Earth's magnetic field will be moving with the wire, and so produce little or no effect (there are "wobbles" in this planets magnetic field of course) there surely must be some kind of magnetic field from the sun and/or other planets which reach Earth--"free energy?" The circumference of the Earth is 25,000+ miles and it does one revolution in 24 hrs--unless I am mistaken that wire will be "whirling" at greater than 1,000 mph--if nothing else, a wire spinning at that speed sounds impressive, especially when you figure in it will be a superior conductor!!! I seem to remember one of the shuttle missions letting out a very long tether--it, somewhat, "mysteriously" burnt or severed--and, if I remember correctly, they noted a large current in the tether they did not expect.... perhaps someone else remembers this incident more clearly? Regards, John |
#13
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On Wed, 27 Apr 2005 18:08:52 -0700, I.Care wrote:
NASA is funding a new type of wire that can transmit power 10 times better than normal wire. Will this make a difference in Audio? Only to those who sincerely wish while closing their eyes very, very hard. http://www.wired.com/news/space/0,2697,67350,00.html An OK general announcement that is rather a hodge-podge of facts and characteristics. Wired is hardly a cutting edge science venue. One particular howler is the construction of a "quantum wire" from a wrapping of several many nanotubes. This is a contradiction in terms. The nanotubes are already quantum wires, in fact they are called 1D forms. Being "quantum" anything, they are consistent in exhibiting non-linear electrical/physical properties. Ohms law (being yet another model that those who lambaste models would be surprised to learn) fails to uniquely express what resistance this wire would exhibit (Onsager's Relation drawn as a Landauer curve). However in conductance measurements, carbon nanotubes will support a billion Amperes per square centimeter. However, no carbon nanotube is a square centimeter, being more often 10s of nanometers in diameter, they are still not square (area) defined (that "quantum" thingy again). The problem of the article is that it is mixing the bulk carbon nanotube properties with the quantum carbon nanotube properties - not at all the same thing. This is why the conductance of a quantum nanotube wire in billions of Amperes plunges to a rather more mundane 1/10th the resistance of copper for a nanotube bundle. The quantum properties quite rightly dismiss any notion of skin effect, current travels inside the tube. In fact, it also distorts the shape of the tube like a snake swallowing a golf ball. Even more interesting is that current will flow in the opposite direction of the applied EMF if there is a sufficient heat differential between the ends (it doesn't take much heat because carbon nanotubes are exceptionally good heat conductors). Firstly, getting current into a carbon nanotube is not a pretty thing as they exhibit what is called "non-reproducible behavior" by their nature of having a great variety of conduction configurations that all arise out of their binding to a contact material. For nano-conductors, contacts dominate everything. All-in-all, the introduction of a new technology is frequently confused as a better version of an old technology - something like saying facsimile would replace the newspaper - or that the utilities would pay us to use nuclear power. All the "forecasts" mentioned in this article rank right up there with these world class pipe dreams. 73's Richard Clark, KB7QHC |
#14
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Richard Clark wrote:
. . . All-in-all, the introduction of a new technology is frequently confused as a better version of an old technology - something like saying facsimile would replace the newspaper - or that the utilities would pay us to use nuclear power. All the "forecasts" mentioned in this article rank right up there with these world class pipe dreams. On the other hand, sometimes the assumption that the new technology will simply replace the old falls staggeringly short. The total market for transistors was initially seen as being the same as for tubes -- replace each tube with a transistor, and that's it. Hardly worth developing the technology to overcome the gnarly manufacturing problems (e.g., extreme purity requirement of the base material). No one foresaw the integrated circuit, making it practical to put the equivalent of hundreds of transistors in a pocket calculator, wris****ch, or even an electric iron. The transistor made possible a whole new technology with applications which were altogether impossible and therefore unimaginable with tubes. But the best that the soothsayers can ever seemingly do is to extrapolate from what we've got right now. Maybe the nanotubes won't end up being simply a replacement for wires, but the basis for a whole new technology we can't now conceive. And maybe they won't. Every entrepreneur does his best to convince investors that his invention will be the next integrated circuit or his garage company the next Microsoft. But the odds are sure against it. Roy Lewallen, W7EL |
#15
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On 27/04/2005 9:32 PM, Mike Coslo wrote:
I.Care wrote: NASA is funding a new type of wire that can transmit power 10 times better than normal wire. http://www.wired.com/news/space/0,2697,67350,00.html hmm. We'd better define better! And with that hard to define effect "mobility", I wouldn't bet the house on it. It looks like the major advantage is the light weight. Of course that may be somewhat negated by the other promise of carbon - the carbon ribbon that will allow us to build a space elevator! Will this make a difference in Audio? The audio geeks will be able to make up stuff for years about this...... Indeed. There's enough snake-oil being sold to audiophiles as it is. Unless and until stereo mags and listeners actually do proper double-blind tests, I think we can assume that this wire (if it ever goes into general production) will be yet another way to liberate hundreds of dollars a foot from gullible consumers. |
#16
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"I.Care" bravely wrote to "All" (27 Apr 05 18:08:52)
--- on the heady topic of "All wire the Same? Maybe not in future." I. From: I.Care I. Xref: aeinews rec.radio.amateur.antenna:29266 I. NASA is funding a new type of wire that can transmit power 10 times I. better than normal wire. Will this make a difference in Audio? Will it transmit power better than silver wire? A*s*i*m*o*v .... I cut it three times already and it's still too short! |
#17
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On Thu, 28 Apr 2005 02:58:43 -0700, Roy Lewallen
wrote: Every entrepreneur does his best to convince investors that his invention will be the next integrated circuit or his garage company the next Microsoft. But the odds are sure against it. Been There [many times] Failed at That [in direct proportion] |
#18
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Does this mean that the resistance per ft for nanotubes is 1/10th that of copper? Rather than "nanotubes" I would assume that they are talking about some kind of "room temperature" super conductor. Ed |
#19
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1/10 ohms of copper certainly is not a superconductor, however, it is a MUCH
superior conductor! Regards, John |
#20
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I.Care wrote:
NASA is funding a new type of wire that can transmit power 10 times better than normal wire. Will this make a difference in Audio? http://www.wired.com/news/space/0,2697,67350,00.html I'm reminded of the hype over bubble memories some years ago. They were going to be the ultimate memory, where are they now? -- Peter |
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