利用核四极矩共振技术探测炸药

介绍了用核四极矩共振的原理进行爆炸危险物品检测的方法及实验测试系统. 该系统运用特殊的激励信号来激发被检测样品中所含的特殊元素¹⁴N（炸药的主要成分），使其产生核四极矩共振，并产生辐射，从而达到检测的目的. 由于该辐射信号的能量非常小(10 nV量级），在通常的环境中很难检测该信号， 这就对此弱信号的检测和提取提出了很高的要求. 本测试系统使用了一系列有效的组合激励信号及弱信号采集、处理技术，在通常环境中成功地检测到了RDX（黑索金）信号.

Detection of Explosives Using Nuclear Quadrupole Resonance Technique

An explosive detection system based on nuclear quadrupole resonance(NQR) is introduced.A special excitation pulse sequence was used to excite and generate NQR signal from the14N nuclei in the explosives.However,the amplitude of explosive NQR signal is usually too low(about 10-8V) to be observed reliably in natural environment.To overcome this problem,an effective multi-pulse sequence combined with small signal detecting and processing techniques was employed when building the NQR measurement system.Using the system developed,we successfully obtained the NQR signal from a 100 g RDX explosive sample at room temperature with a probe-to-sample distance of 5 cm and an acquisition time of 5 s.