StarryNight

Scientists in Japan have developed a new technique for sensing explosives in luggage and landmines. The paper, published today in the Institute of Physics journal Superconductor Science and Technology describes how radio waves can be used to identify specific explosives, such as TNT. The new method could be used in future to screen baggage at airports.

Source.

I was so gladdened by this find that, even though the story is 6 months old, I thought I'd share it with you, and you and you. Ippon akbar!

Will this type of technology enable mobile, radar type sensing of terror threats or will eg baggage have to be honed in on at close quaters?

What about explosives made from fertilizer, will they have a specific and distinctive signature too? Fertilizers are nitrogenous arent they? And bombs therefore too...

What about hydrogen peroxide... terrorists use that too don't they?

Corona688

Fertilizer bombs are primarily ammonium nitrate, which is heaping nitrogenized nitrogen on nitrogen...

I do wonder how the device would respond to things like chlorates. Perhaps it's only good for high explosives...

barbos

If it is small explosive one can wrap it in foil to shield it from radio waves.

Agemegos

I'm not whether that works perfectly. I have been told that radio waves incident on a conducting surface induce currents that produce magnetic fields on the far side, with the effect that they effectively penetrate by a distance proportional to the wavelength. I'm not certain that that is true, nor that if it were it would be enough to make the detector work. But even if not, you can always detect and examine any metallic containers.

camp freddie

Sounds like NMR (Nuclear Magnetic Resonance). It's commonly used for carbon and hydrogen, and works really well. I think it's a hydrogen-based NMR scan that's used in MRI scans in a hospital.

The problem is that they need a bloody huge magnet and radio waves are probably blocked/reflected by metals.
Maybe this technique has found a way to do it with a less powerful magnet...

Sod it, Wikipedia beats me to it: http://en.wikipedia.org/wiki/Nuclear...pole_resonance

Looks like a quadrupole doesn't need a magnetic field to orientate all the nuclear spins. Sounds like it could really work, though it might be possible to block the RF with tinfoil or whatever. It should be useful in conjuction with X-rays and all the other detection techniques.

premjan

So now they will have to ban foil in luggage.

StarryNight

From wikipedia source:
So perhaps remote detection is on the cards?

Key:

• Western Bhagdad
• Central London

wordy

I guess the evil terrorists then set the explosives so they explodes when detected? then the scene is rid of detecting devices for a while cause they cost very much I guess? Or are they like GPS, now almost all the high tech phones have a GPS module. Maybe all Mobiles could have an explosive detector within some 10 years too. When they detect something they automatically phone a Central for War on Terrorism Intelligence Agency and they map the position with help of the built in GPS receiver? Smart?

premjan

To detect the detector you would have to pick up the magnetic excitation field. It sounds like something fairly generic, so the danger of false explosion would be high.
http://en.wikipedia.org/wiki/Nuclear...pole_resonance