No they don't. Nuclear magnetic resonance requires a strong external magnetic field. The strongest superconducting magnet you can buy today induces a resonance (the Larmor frequency) in protons at 950 MHz... but it costs about ten million dollars and only does that over a tube about five centimeters wide. The absolute strongest MRI magnets today top out at about 1/3 of that magnetic field, and most are far less.
Microwaves heat food via RF heating, which is an electric effect, not a magnetic one. No relationship to the mechanism of NMR at all.
As for the article topic, nuclear quadrupole resonance is similar to NMR except that, instead of using a magnetic field to induce an energy splitting (which gives you the Larmor frequency), you take advantage of electric field splitting instead. This only works in atoms that have a quadrupole moment, and the only one of those that's present at high concentrations in explosives (and living things too) is nitrogen-14.
I'd be more inclined to suspect that great big antenna up on top of the Empire State. Half the TV and radio stations in NYC transmit from there, since it's now the tallest antenna in Manhattan.
Regarding the ozone, none that I can think of - but helium is expensive (about $5.50/liter), and a non-renewable resource, since it's light enough to dissipate from the atmosphere into space. Also, the only useful source of helium at the moment is natural gas deposits that are unusually rich in the stuff; there's so little of it in the atmosphere, and it's such a pain to liquefy (4.2 Kelvin!), that condensing it out of air is infeasible.
I assume that they're doing no such thing, though. Non-superconducting NMR magnets are available to at least 2 Tesla, presumably they're using similar designs.
Re:Physics has always been ethically compromised
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Ununoctium Wrapup
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· Score: 2, Informative
The case has been rather overstated. David Goodstein, a current professor of physics at Caltech, wrote an article on this subject (warning: PDF). The relevant portion starts on page 3 - in summary, the data points that were discarded were being used to verify a separate formula for Stokes' law. A more recent analysis of all the points, published and not, doesn't show a bias regarding the charge value.
That's how the system works, yes. The MTA has 214 substations around the city, which are fed something between 11-27 kV AC, transformed to 400 V AC, and rectified to 600 V DC.
It's only within the last ten years that they finally retired all of the old pre-solid-state rotary converters in the system - running power backwards through them would have actually worked.:)
The new cars actually have AC motors - the DC third rail powers a battery on board, I'm not sure exactly what the AC conversion tech is. There's still a couple thousand DC-motored cars riding the rails, so I'm not expecting to see the system switch over to AC distribution....
Techniques for finding biosystems elsewhere in the universe, and trying to figure out how life gets started; finding other places amenable to human life; how those places formed.... it's fairly broad.
As for the 512-processor Origin, the only thing that jumps to mind is modeling a single-celled organism, down to the molecular level.
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Nope. If the spelling is close enough that it's obvious who was intended, it counts. Even if it's not entirely flattering.
No they don't. Nuclear magnetic resonance requires a strong external magnetic field. The strongest superconducting magnet you can buy today induces a resonance (the Larmor frequency) in protons at 950 MHz... but it costs about ten million dollars and only does that over a tube about five centimeters wide. The absolute strongest MRI magnets today top out at about 1/3 of that magnetic field, and most are far less.
Microwaves heat food via RF heating, which is an electric effect, not a magnetic one. No relationship to the mechanism of NMR at all.
As for the article topic, nuclear quadrupole resonance is similar to NMR except that, instead of using a magnetic field to induce an energy splitting (which gives you the Larmor frequency), you take advantage of electric field splitting instead. This only works in atoms that have a quadrupole moment, and the only one of those that's present at high concentrations in explosives (and living things too) is nitrogen-14.
I'd be more inclined to suspect that great big antenna up on top of the Empire State. Half the TV and radio stations in NYC transmit from there, since it's now the tallest antenna in Manhattan.
Looks like you need an HP 67X. Don't forget to pick up the extended-length belt case.
Erm, what exactly would be the problem with this?
Regarding the ozone, none that I can think of - but helium is expensive (about $5.50/liter), and a non-renewable resource, since it's light enough to dissipate from the atmosphere into space. Also, the only useful source of helium at the moment is natural gas deposits that are unusually rich in the stuff; there's so little of it in the atmosphere, and it's such a pain to liquefy (4.2 Kelvin!), that condensing it out of air is infeasible.
I assume that they're doing no such thing, though. Non-superconducting NMR magnets are available to at least 2 Tesla, presumably they're using similar designs.
The case has been rather overstated. David Goodstein, a current professor of physics at Caltech, wrote an article on this subject (warning: PDF). The relevant portion starts on page 3 - in summary, the data points that were discarded were being used to verify a separate formula for Stokes' law. A more recent analysis of all the points, published and not, doesn't show a bias regarding the charge value.
Unrelated but perhaps relevant, Goodstein also has an article titled Conduct and Misconduct in Science online.
That's how the system works, yes. The MTA has 214 substations around the city, which are fed something between 11-27 kV AC, transformed to 400 V AC, and rectified to 600 V DC.
:)
It's only within the last ten years that they finally retired all of the old pre-solid-state rotary converters in the system - running power backwards through them would have actually worked.
The new cars actually have AC motors - the DC third rail powers a battery on board, I'm not sure exactly what the AC conversion tech is. There's still a couple thousand DC-motored cars riding the rails, so I'm not expecting to see the system switch over to AC distribution....
Building 7 also housed NYC's emergency response bunker.
Techniques for finding biosystems elsewhere in the universe, and trying to figure out how life gets started; finding other places amenable to human life; how those places formed.... it's fairly broad.
As for the 512-processor Origin, the only thing that jumps to mind is modeling a single-celled organism, down to the molecular level.
The NASA Astrobiology Institute site has more, though it's scarce on useful details.