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Carbon Magnets At Room Temperature
Bolie writes: "Trying to make high temperature super conductors yielded an unexpected result. The pure carbon bucky ball material was put under pressure to make sheets. That worked. Picture microscopic bubble pack. But the result was a sheet that was magnetic at room temperature. It has not escaped the attention of the discoverer, Tatiana Makarova, that this might be useful for a non-metallic computer memory. The material is also lighter than metals, flexible and transparent. Lasers anyone?"
Actually, no. What the article was saying was that the material is the first non-metallic material that was magnetic at room temperature (meaning that other non-magnetic materials weren't, at least not at room temperature). The point about the material being magnetic even above 200C was about the material's Curie point (above which the material stops being magnetic) being much higher than any other material, the previous record being 255C which was held by a different form of buckyballs. So this material is interesting because it's the first non-metallic material to be magnetic at room temperature and has a higher Curie point than any other non-metallic material to date.
Apparently, the material's magnetism could be linked to unpaired electrons, which can sustain a magnetic field when their spins are aligned (in this case there are unpaired electrons). One possibility is that they bond in triangular groups of three, which would provide for unpaired spins.
Although, to be used as computer memory it would have to have uniform magnetism, not just in pockets. But either way it's a significant step forward.
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When the pin is pulled, Mr. Grenade is no longer our friend.
- room temperature.: Aound 21C.
- the new material was magnetic even above 200 C..The word "even" seems to imply that it is a feat to go above a certain temperature . Which implies that with higher temperature, materials tend to lose their magnetism (Curie point). Which implies that the material is also magnetic for all temperatures below 200 C. Which includes 21C, i.e. room temperature. Probably, the reason for the
strange formulation was that the researcher didn't have any oven handy which went over 200 C, or that any higher temperature fried his magnetism measuring equipment, or whatever. So he was just saying that at 200 C it was keeping
its magnetism, and that it was likely that it would keep it even beyond that mark.
- Until now, the highest temperature at which a non-metallic material was magnetic was 255 C. The words "until now" means "all materials known before" this one was discovered. Meaning that the 255 C refers to a different material. Oh, and btw, 255 C (that's minus 255) is below room temperature.
So where is the contradiction?yes, that's what is happening. IE5.5 isn't showing the minus sign on -255 even though it's there in the source. That's pretty scarey.
They used a Soft Hyphen ( or ) character instead of a minus sign. Browsers are not supposed to display a Soft Hyphen unless the line is broken at that point.
Not only will they give us a new form of storage, but they can also be used as a treatment for AIDS.
Interesting how versatile a simple molecule can be..
- And
- here's a report on single buckyball transistors.
Enjoy!MS: ALL YOUR
It's a mistake in the HTML, the 250 should be -250, but they put a soft hyphen in instead of a minus sign or a dash.
By writing to a particular memory cell, light passing through that location may be polarized differently because of the different magnetic field. This could then be used to verify the particular state it is in. This could be a very fast way to read the memory.
You can read the thing with a magnetic head.
I believe minidiscs work like this. Someone's bound to correct me if i'm wrong.
To write, the laser heats a very small spot on the disc (to above the Curie point), and the magnetic head magnetises the spot in the required orientation. The use of the laser allows a much smaller spot on the disc to be targetted than with the magnetic head alone.
Reading is done without the laser, just the magnetic head in a manner similar to a hard disc.
Jeff
stty erase ^H
(Ignoring the fact that most of the world calls the sport the Americans call soccer 'football'; I'll write with American usage:)
y ba ll/c60a.htm )
Right, and wrong. Buckballs are C-60 and soccerball shaped, but some relatives are indeed football shaped (more like a rugby ball, really), and have 70 or 76 Carbon atoms inside.
"C60 and C70 have similar properties, with six reversible, one electron reductions to C60(6-) and C70(6-) having been observed, whereas oxidation is irreversible. The first reduction for both fullerenes is ~1.0 V (Fc/Fc+), indicating they have electron accepting properties. C76 exhibits both electron donor/acceptor properties. C60 has a tendency of avoiding having double bonds within the pentagonal rings which makes electron delocalisation poor, and results in the fact that C60 is not "superaromatic". C60 behaves very much like an electron deficient alkene and readily reacts with electron rich species. " (from
http://www.bris.ac.uk/Depts/Chemistry/MOTM/buck
Absolute zero is -273.15C (or is it .16)
or 0K There is no such thing as 'degrees kelvin'; the proper way to say it is 'zero kelvins'.
And this discovery has absolutely nothing to do with superconductivity; only that they were trying to produce a superconductor when they discovered it was magnetic. This is not an advancement in superconductivity. They didn't produce a superconductor. That's obvious even without reading the article...
Also, you are correct about superconductors.. but... the reason microprocessors work is because they are full of SEMIconductors... transistors... you HAVE to have resistance.. you can't build logic with pure superconductors.
What about Spherical Magnets ?
:)
Pretty cool. Now if I could only think of a use for them...
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There is a bug in some browsers that fail to display the - sign. The articl may appear to say the previous temp was 255c when it actually says(look in the source) -255c.
I don't know how to post a story update, so I'll do this here.
The Kruger Dunning explains most post on
Actually, that shape is technically called a truncated icosahedron, IIRC. That way it doesn't matter what sport you play: everyone is equally confused... ;-)
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