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FSU Sets 7 World Records In High Magnetics Research
spence calder writes "FSU's High Magnetic Field Lab, more specifically my Kenpo teacher, just broke 7 world records, and brought the record for a superconducting magnet to 25 Tesla. Check it out at FSView and a more detailed article here. Now if only our football team was that cool." And if you'd like your magnetic toys to shoot metal bits,
Jason Rollette points to his
railgun project, which looks like good, clean, high-voltage fun.
That'll keep those damn Americans off my base.
FP
Anti-social? My code is just platform-specific.
Yep, Alfred Nobel probably said a similar thing when inventing dynamite.
Now if only our football team was that cool Are you sure you're a geek?
Everything seemed to be going so nice
'till the end of all beings punched right through the ice
No one knows the effects of an 25 Tesla magnet on biological tissues. In addition, in order to get useable information out of an MRI system, one must hit it with radiofrequency (RF) waves. The higher the static field is, the higher these frequencies are going to be. A 7-tesla magnet uses frequences around 300 MHz. Therefore, by extrapolation (which I believe is right, since I know that a 9T system uses about 383 MHz), a 25 Hz system would need about 1.1 GHz. This might very well be extremely detrimental to biological tissue. In other words, to do MRI, you'd have to cook your sample.
Finally, to truly achieve a resolution advantage, you will need very powerful gradients. The gradients one would need to take advantage of such a system would be gigantic, at least tens if not hundreds of Tesla per meter. This would be very difficult to design for samples as large as a human body, if not impossible with today's technology, and at the very least extremely expensive.
Personally, I can see a 25 Tesla magnet being useful, just not for MRI. Perhaps for NMR being using not for imaging purposes, but in the study of non-soft condensed matter systems (i.e. not biological or organic, but solid state). It would be useful for examining superconductivity also.
It is a bit more tricky than just 'add more coils' or 'use more current'.
Back at university we had a 14T He cooled magnet. Reaching 12T was standard. No issues. But having 2 more Teslas out of that thing took many tricks: pumping off the Helium to make it even colder, increasing current near the limit. The thick copper cables got pretty warm. And heat and superconducting coils and Helium don't mix well, so for us, 15T was unreachable.
It's not unsimilar to the 10s/100m in athletics: Everyone get's close, but it took some time until someone finally was faster than 10s.
20T was the limit for 'usual' magnets. Getting more needed a new trick. But I admit that for people not using this stuff, it looks very much like no particular breakthrough. Like I never cared if I can run 100m in 10.1 or 9.9s. It's just 2% difference after all, isn't it?
http://www.fsunews.com/vnews/display.v?TARGET=sho
Thats one hell of a soldering iron.
Speaking at Defcon 12 - Credit Card Networks Revisted: Pen
None of my credit cards seem to be working anymore...