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#1
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Hogwash.
MRI detects primirily concentration of hydrogen atoms. It requires quite strong magnetic field with precise gradient. What you describe is using different principles. "Dana" wrote in message ... Hogwash. You seem not to understand what can be done with electronics. There are some devices that use the priciples of a MRI and shrink it down to a hand held sized device to scan for explosives. Since the compounds in explosives give off a unique signature after being exposed to a strong magnetic field, that signature is then stored in memory. Now your sensor emits a magnetic field, and the reciever looks for the signature of the explosives. So it is only a matter of expanding your signature library, and your receiver can be programmed to look for pretty much anything. This is only one of many new tools that are out. The semiconductor junction detector has been out for around 30 years. |
#2
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![]() "Alexander Grigoriev" wrote in message link.net... Hogwash. Yep, that is all you have. Another such technology is called Quadrapole Resonance or QR. Originally developed by the Department of Defense to detect land mines, QR directs a beam of radio waves at an object. The radio waves will penetrate the object and infuse whatever is inside. When the radio waves pass through an explosive material, the molecules of that material will polarize or develop a small electrical charge. As the molecules lose their charge, they emit a very weak radio frequency signal that can be picked up and analyzed to detect explosives. Because it relies on harmless radio waves that are easy to produce and monitor, this technology is considered to be one of the most promising in the field. MRI detects primirily concentration of hydrogen atoms. It requires quite strong magnetic field with precise gradient. What you describe is using different principles. And another one that needs to keep up on technology Here are some links that will explain what I am talking about. http://gazette.gmu.edu/articles/4925/ Sauer's studies are focused on nuclear quadrupole resonance (NQR), a type of radio frequency spectroscopy that can help identify many substances without the use of a large static magnetic field http://www.americanscientist.org/tem.../assetid/39131 The phenomenon of nuclear quadrupole resonance is akin to nuclear magnetic resonance, which is the basis of magnetic-resonance imaging. But unlike MRI scanners, instruments based on nuclear quadrupole resonance are not required to generate strong magnetic fields. "Dana" wrote in message ... Hogwash. You seem not to understand what can be done with electronics. There are some devices that use the priciples of a MRI and shrink it down to a hand held sized device to scan for explosives. Since the compounds in explosives give off a unique signature after being exposed to a strong magnetic field, that signature is then stored in memory. Now your sensor emits a magnetic field, and the reciever looks for the signature of the explosives. So it is only a matter of expanding your signature library, and your receiver can be programmed to look for pretty much anything. This is only one of many new tools that are out. The semiconductor junction detector has been out for around 30 years. |
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