Stand-off Raman spectroscopy: a powerful technique for qualitative and quantitative analysis of inorganic and organic compounds including explosives

摘要: A pulsed stand-off Raman system has been built and optimised for the qualitative quantitative analysis of inorganic organic samples including explosives. The consists a frequency doubled Q-switched Nd:YAG laser (532 nm, 10 Hz, 4.4 ns pulse length), aligned coaxially with 6″ Schmidt–Cassegrain telescope collection scattered light. was coupled via fibre optic bundle to an Acton standard series SP-2750 spectrograph PI-MAX 1024RB intensified CCD camera equipped 500-ps gating option detection. Gating proved be essential achieving high signal-to-noise ratios in recorded spectra. In some cases, also allowed suppression disturbing fluorescence signals. For first time, spectra performed using both univariate multivariate methods data analysis. To correct possible variation instrumental parameters, nitrogen band ambient air used as internal standard. method, obtained at distance 9 m on sodium chloride pellets containing varying amounts ammonium nitrate (0–100%) were used. quantification ternary xylene mixtures (0–100%), 5 m calibration yielded R 2 values 0.992, root mean square errors prediction 2.26%, 1.97% 1.07% o-, m- p-xylene, respectively. Stand-off 10 m detection limit 174 μg NaClO3. Furthermore, assess applicability spectroscopy explosives “real-world” scenarios, their different background materials (nylon, polyethylene part car body) presence interferents (motor oil, fuel oil soap) 20 m investigated.