Nuclear quadrupole resonance (NQR) method and apparatus for detecting a nitramine explosive
US6104190A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 1998 |
| Grant date | Aug 15, 2000 |
| Priority date | — |
| Expiry date | Nov 17, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/441
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A Nuclear Quadrupole Resonance (NQR) method and apparatus for detecting the presence of a nitramine explosive, with a reduced probability of spurious triggering of consumer electronics. In the method and apparatus, a signal is emitted towards a nitramine explosive so that a nitro group in the namine explosive produces an NQR resonance signal. The NQR resonance signal is then detected to thereby detect the presence of the nitramine explosive. If the nitramine explosive is RDX, the NQR resonance signal of the nitro group is at a frequency which is either 502.3 kHz, 500.5 kHz, 405.1 kHz, 396.2 kHz or 384.1 kHz. Such frequencies are much lower than those in conventional detection techniques. As a result, the probability of the undesirable spurious triggering of electronic items exposed to the NQR RF pulses will be reduced, due to the reduction in induced voltage at lower frequency. The detection sensitivity is also reduced, but in many cases will still be adequate to detect nitramine explosives.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.