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Record-Setting 100+ T Magnetic Field Achieved At Los Alamos
New submitter schrodingersGato writes "Researchers at the Los Alamos campus of the National High Magnetic Field Laboratory achieved a record-setting 100.75 Tesla magnetic field. To do this, scientists placed a resistive magnet (a sophisticated electromagnet) coupled to massive bank of capacitors within another magnet fixed at a 'lower' magnetic field. A short-lived pulse two million times stronger than the Earth's magnetic field was generated. The magnet itself made an eerie sound as it was energized (video). Prepare for the birth of Magneto!"
The strongest MRI currently used on humans is 9.1T and a 13T MRI scanner is being built - might already be finished. Given that the 9.1T is good enough to see individual neurons, the 13T scanner might be good enough to start seeing the fine structure of the synapses. I look forward to seeing the photos that will hopefully be published once the scanner gets going.
It would be interesting to see how far you could go before the damage becomes excessive. Would it be possible to build an MRI capable of directly observing the proteins that control and form memories? Could you observe the tau protein unpeeling as Alzheimer's begins? (Long before structural changes occur, which in turn is long before symptoms appear.)
How about archaeological uses? Could a high-power MRI reveal something of the mental state of the various bog bodies that have been found? What about Otzi? If we can directly observe memory structure, could we interrogate his brain to find out what happened to him?
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
You're damn right 100T is incredibly powerful. Most MRI rings for humans max out at 3T. Some of the experimental medical rings are 7T-8T and you have to be really careful working around those. I can't imagine 100T. Hell, we stuck a dumpster to a brick wall with a 5T magnet.
My bad, it's 11T. See links below for info.
This is the existing 9T MRI with 80cm bore.
http://medgadget.com/2007/12/94_tesla_monster_mri.html
This is the whole-body 11T MRI being built
http://irfu.cea.fr/en/Phocea/Vie_des_labos/Ast/ast_visu.php?id_ast=3058
Some of the underlying technology:
http://www.microwavejournal.com/articles/print/2551
http://www.microwavejournal.com/articles/10402-software-platform-for-mri-phased-array-system-design-optimization
http://www.hfmmagazine.com/hfmmagazine_app/jsp/articledisplay.jsp?dcrpath=AHA/PubsNewsArticleGen/data/0403HFM_NEWS_Construction
http://www.aapm.org/meetings/05am/pdf/18-2826-94182-387.pdf
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
What I find interesting with this is that some "magic physics" theories postulates funny things to be possible at some ~50 tesla strenght. Probably won't show up anything, but testing them to falsify is always a noble goal.
They went to pulsed 200T in 1950-ies (see the MK2 in 1956).
Questions raise, answers kill. Raise questions to stay alive.
14 years ago I routinely used a 12T NMR, and we had a 17T model in the basement (time on that one was a bit harder to get).
However, to be useful for most forms of NMR the field has to be very uniform and stable over long periods of time. You can't do that with pulses or some of the other techniques used at this high-field lab. There are of course all kinds of other things you can do there.
MRIs tend to be much weaker than NMRs. The problem is the bore size of the magnet. Scaling up the size of a magnet is very difficult, and it takes a lot more energy to make a weak field the size of the earth than a strong one that you can fit a skinny test tube inside. This is similar to the difference between temperature and heat. A match and a bonfire might be the same temperature, but the bonfire puts out way more heat.
Medical MRI tends to be only a few T at most. Really big ones are in the very low teens, and are VERY expensive to build. Of course, MRIs have spacial resolution and NMRs typically do not. An NMR probes fairly complex chemical relationships but does not generate a spacial image. An MRI probes fairly simple chemical relationships (often just the presence of water or a contrast agent), but it takes a 3D picture.
The other more modern trend is building bigger NMRs but instead of making them more powerful using extra magnets to cancel out the field outside of the dewer. This makes them easier to site - and people don't get injured by flying tools if somebody is careless. High-field NMRs can be very dangerous when performing operations like filling with the aid of gas cylinders (with very long hoses). Shielding or not, another big danger with either NMRs or MRIs is ventilation. If something causes the magnet to quench you can get huge volumes of He/N2 liberation which will quickly displace all O2 in even a large room.