Key Star Trek tri-corder boffinry breakthrough A breakthrough in small, high-powered magnets could lead to handheld magnetic resonance scanners with similar capabilities to those of today's room-sized medical and scientific instruments. According to a report in MIT Technology Review, Doctor Federico Casanova and colleagues at the Rheinisch-Westfälische Technische …
to check if a prison guard's blood contains too much iron. Have you never seen X-men? It's how magneto escaped from prison! Magnetically imaging the blood would mean that they can tell if magneto can extract the metal from it to make projectiles, floating platforms and all sorts of metal mayhem.
Nuclear magnetic resonance spectroscopy can be used to analyse all sorts of chemicals. By googling 'nmr blood samples', for instance, I've come across a paper on testing blood plasma to look for cancer.
For more details you'll have to ask someone who hasn't forgotten most of their chemistry degree.
NMR is quite good for spotting benzene in dodgy vodka: the benzene peaks show up a treat as we found when we put an absolute alcohol sample in my university's first NMR machine to look for hydrogen bonds. We were surprised to see them - thought the abs.alc. would have too much water in it - but the mutter of 'No more abs.alc. for me' that ran round the room made us grin[1].
[1] ginger beer spiked with ethanol or abs.alc. was a popular drink among chemistry students when I were one.
All very well having a nice portable mega-magnet, but even assuming it doesn't have equally mega- power requirements there's still the fact that you'd be wandering around in public with a bloody strong magnet.
External shielding needed, I guess (ruling out a proper "stand well back and scan" tricorder), unless you want archaeologists braining each other with flying shovels, and bricked hard drives in adjacent offices.
One can only hope said small and powerful magnet is small and powerful enough to fit inside a wristwatch, allowing it to be surreptitiously deployed in the lowering of the zip of a lady's dress behind her back in a hands-free plausibly deniable fashion. Then we will truly be living in the future.
Generating stonking big magnetic fields is all well and good - so long as you're sure there's nothing made of iron, steel, or (less seriously) nickel hanging around. Otherwise you're in danger emulating "Little book of bunny suicides" rabbit standing in the middle of the road between a knife shop on one side and an electromagnet shop on the other. Piercings would be bad. Hip replacements or pins in bones would be worse.
It's also incompatible with magnetic storage media like PCs, which would probably be inconvenient.
Quite so, there's a number of reasons MRI units in hospitals have carefully controlled access and patients have to be interviewed before being cleared to enter the magnet. Of greatest concern are things like pacemakers, surgical clips and metal particles in the eye sockets.
Another thing that MRI machines have are large RF shields around them. NMR signals are extremely small and even small amounts of outside RF noise can swamp them. There's also the small matter of a clinical system requiring a three phase electrical supply for the RF and gradient coil amplifiers.
Unfortunate reality nerdery aside, one possibly entertaining side effect would be down to the fact that humans are essentially large bags of conductive liquid. Move a powerful magnet next to a conductor and you get large eddy currents. If that conductor happens to be someone's head, the eddy currents will flow through the brain and induce disorientation, nausea and vertigo. Wave one of these quickly past a patient's head and watch them fall over...
Now I've had some more time to think about it, this breakthrough is going to allow the creation of some insanely powerful electric motors. This work is also going to help all sizes of motors to become more powerful. I can't wait to get lighter more powerful radio controlled model motors and even very powerful tiny servo motors. Then there's bigger applications like more powerful electric cars and even bikes.
I think they are about to become very rich :) … Even just all the improved motor applications for this technology is vast.
Let me point out that in the States, fMRI machines are as we speak being certified (how? by what authority?) as lie detection machines for legal investigations. They are labeled 100% reliable. No, you don't get an opinion about it.
Now I see, coming with the speed of a crashing satellite, field fMRI caps to be slapped on the heads of "criminals" for instant lie-detection.
Don't let it happen.
As already mentioned:
Destruction of any magnetic data in the vicinity. Not just computers but credit cards, building/travel passes, mobile phones, etc.
Lethal flying objects if there's anything ferromagnetic in the area. They have strict rules to stop people leaving iron objects in scanner rooms, because people have died from a moment's carelessness.
But there's also endless opportunities for sabotage by leaving one of these in just the right place.
And there will of course be lots of '"funny" "practical jokes".
It's all that magnetism pulling them together. Make's 'em small 'n' dense, so it does.
Any stronger and they're in danger of producing neutronium accidentally, or if they let a handful go at once, it's black hole time!
Wheee! What has it got in its pocketses? Oh noes, a pocketful of black hole!
Um, right, I'll get back to the beach, then, shall I?
if you're curious about powerful magnets, neodymium magnets are cheap as anything - I have a pair of 2cm ones (about £10 each when i got them), not sure about measuring the strength, but of the 7-8 people i've showed them to, i'm the only one who can separate them (and then it's the technique I use to orientate them so the field is weaker, then i can just about pull them apart - although if the first attempt doesn't work i need a few minutes before trying again!)
One of my mates made the mistake of allowing his arm to get between them, he dropped one while the other was on the table below - ended up with 2 powerful magnets clamped around his arm, very painful, and not very easy to remove either!
Powerful magnets are cheap, fun, and very very dangerous :)
No power required.
It's *real* feature is it takes standard MRI sample tubes while maintaining a *very* constant magnetic field in the sample zone. good enough to build a "portable" (not sure if this will be laptop or more Osborn luggable for those who remember such things) MRI unit.
Imaging, or samples which don't need insertion are likely to be a *lot* harder.
But still pretty neat.
As long as the joint replacement / pins have been in for a bit (about a month) then there's no problem having a scan with them. Apart from your images look crap, and there's always the risk of some heating.
The Article mentions that 0.7T "is still substantially less than the multi-Tesla fields required for MRI scans" - Not true, there are scanners in the sub 1T field (0.5+) that are in use, such as this one http://www.fonar.com/su_specs.htm although the higer Tesla has it's advantages in most cases.
John
BSc(Hons) Diagnostic Radiography
I'm guessing this is all patented even though it was discussed years ago on usenet forums which is full of prior art. Magnets stronger than what was used in the 1st NMRI machine have been around for years and even old phones have more processing power than was used in the 1st dozen machines.
I'd guess that the magnet is a cylindrical Halbach array, especially if they're eventually aiming for a 2T field. This would imply that the sample volume is on the order of a couple of mm in diameter. This kinda rules out using the magnet for detecting liquid explosives in sealed containers (though a a larger Halbach array works nicely for that).
Lacking a mention of the homogeneity of the magnet, I'd wonder if the magnet would be capable of high resolution proton NMR, though the high field would be useful for Phosphorus or other biologically significant nuclides. With the small sample volume, the RF power requirements would be pretty modest, so it would be possible to make an easily portable NMR spectrometer using that magnet.
I happened to watch Mystery Men just before meeting Dr. Casanova, so can't help thinking of Casanova Frankenstein when I see his name.
Uh, if you'd read the article pointed (or even previous comments) at you'd know the magnet was designed *specifically* to accommodate the standard 5mm MRI sample tubes with the level of homogeneity needed to run a scan.
Halbach arrays are a neat way to double the available field strength in a particular direction, although the Wikipedia (I know but I'm no magnet expert)
http://en.wikipedia.org/wiki/Halbach_array#Uniform_fields
comments that there are *several* ways to design magnets with a high field through the core but near zero outside field (which should also mean a lighter magnet field shield needed to protect hard drives, body piercings etc from a powerful magnetic field and the "hilarious" consequence)) and a strict Halbach design requires a *continually* varying field vector as you go round the circumference. Impressing that field on a single hollow cylinder of magnetic material would be quite challenging from a mfg POV..
It *might* be a halbach (incidentally the article mentions that the ideal was originated in a 1973 paper). When people talk homogeneous properties in metals I think powder metallurgy using plasma assisted (low voltage, high current) sintering. Small grain size, quick (press times reduced from hours to minutes) so small uniform grain size retained and tight composition control.
"Hmmm.... wonder if these magets could be used to develop anti-gravity drives..."
No. Although the thrust to weight ratio of a good magnet (from an article on Halback arrays as it happens) is about 50:1. That's 5x the T/W of a jet engine and in low performance rocket engine territory.
As for anti gravity. Keep dreaming.
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