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Another Form of Carbon: Magnetic Nanofoam
mhh5 writes "Researchers publishing in Nature have discovered yet another form of carbon. Apparently, this stuff is temporarily magnetic after it is made (at temperatures of ~10,000 C) and is a spongy solid. So that's five (give or take one?) allotropes for carbon: amorphous, graphite, diamond, fullerenes, and nanofoam. Collect them all!"
gets all the diamonds we can afford you insensitive clod!
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A new form of carbon that wasn't predicted by SciFi!
Can I guess you are opposed to MRI's too? My grandfather, a veteran of WW II couldn't have MRI's because in gaining his two purple hearts, he also got shrapnel lodged in his skull, which because it could become dislodged in an MRI, he couldn't have. About a year ago, he had some hemoraging in his brain, and they had to basically go in blind to releave the preasure. Oddly enough, he outlived his brain surgeon, who died of a heart attack soon thereafter, although he followed himself in October. Such is life...
fullerene
,one above the other. These layers 3.35A degrees apart and are held together by weak van der waals forces only.These layers can slide over one another.Thus it is very soft. Fourth electron of each c-atom forms delocalized
p-system.
n.
Any of various cagelike, hollow molecules composed of
hexagonal and pentagonal groups of atoms, and especially
those formed from carbon, that constitute the third form of
carbon after diamond and graphite.
Diamond, Graphite and Fullerene forms are crystalline, the amorphous forms are coal, coke, charcoal, lampblack, gas carbon etc.
In diamond, each C-atom is covalently bonded to four other C-atom to give a tetrahedral unit. In diamond each C-atom is sp3-hybridized.Therefore each C-atom forms four sigma bonds with neighbouringC-atoms. In diamond C-C-C bond angle is 109.5 degrees.These basic tetrahedral units unite with one another and produce a cubic unit cell.
In graphite each C-atom is covalently bonded to three C-atom to give trigonal geometry. Bond angle in graphite is 120 degrees. Each C-atom in graphite is sp2-hybridized. Three out of four valance electrons of each C-atom are used in bond formation while the forth electrons free to move in the structure of graphite. Basic trigonal units unite together to give basic hexagonal ring. In hexagonal ring C-C bond length is 1.42A degrees. In graphite these rings forms flat layers. These layers are arranged is parallel
During the irradiation of diamond by atoms, many bonds are broken, leading to point defects and eventually to clusters of defects. At a high enough irradiation dose, amorphization of the crystal structure may occur and two specific amorphous forms of carbon may appear: the tetrahedrally bonded Diamond-like Amorphous Carbon which will be denoted by ta-C and the sp^2 bonded Graphite-like Amorphous Carbon named a-C. These two structures can be distinguished clearly by their macroscopic and microscopic properties. The former material has higher density, is transparent, electrically insulating and much harder than the latter. From the microscopic point of view, the ratio of fourfold, diamond-like bonds to threefold, graphite-like bonds (sp^3/sp^2) determines the kind of structure obtained.
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They Are Vermin Feeding On Each Other's Feces.
I Hate \.
The article was egregiously low on detail. (Googles a bit...) Here is a more technical article that explains the magnetism as a result of temporary unpaired electron spins (surprise!). The magnetism occurs at temperatures below 90K, so it's fairly remarkable that they can jerk this stuff from 9700K down to 90K and have it not shatter!
Human being (n.): A genetically human, genetically distinct, functioning organism.
I know they're using carbon aerogels to make really large capacitance caps in the 1-100Farad range. Does this new nanofoam have similar potential for making new capacitors with higher surface area/mass ratios?
I've had enough abrasive sigs. Kittens are cute and fuzzy.
I already commented on this over here but hey...
I'm a space nut so you can guess where I'm going with this.
Aerogel is a really cool substance. It's glass foam that's very very light and it's an excellent insulator. I don't know about it's radiation blocking properties though.
If this carbon foam is of comparable weight as aerogel (negligible), it's perfect for space use. The lighter the better since it costs $thousands/kilo to get stuff off the ground. If it blocks radiation, fantastic. Water and metal are the big rad blockers now but they're heavy. If it can act as a good insulator too, you're golden. If not, a sandwich of aerogel and carbon nanofoam could act as a heat trapper so you don't freeze and a radiation blocker so you don't get zapped. And all for practicaly no weight. Shazam!
Blaze a trail to the New World
Showoff :)
I just did a report for my Engineering and Architectural Design concerning the use of carbon-nanotubes.... and not one single person, student or faculty, had ever heard of them. This is wholly depressing, BUT afterwards several students and a few teachers came to talk to me privately about it, and ask for more information.
Does anyone else think that scientific news actually DESERVES and NEEDS to be heard by the general populace? Even if they don't get it, they'll still know about it. Hell, most of them probably don't get The Apprentice, but they keep watching.
I like to place meaningful quotes in my sig, so people will know that I know what meaningful quotes are.
That this nanofoam loses its ferromagnetism with time suggests that nanofoam is fundamentally unstable at the molecular level. Presumable its ferromagnetism is due to a separation of the electron orbits between adjacent atoms caused by being in a "foam". Like a soap or detergent foam, it presumably breaks down over time resulting in the condensation of the carbon atoms back into a normal non-magnetic separation. I haven't read the original paper so this is just an educated guess.
And if it's still on her finger at the time, your marriage won't last long either!
Hey kids, there's only 5 days left 'til Yak Shaving Day!