METHOD FOR REMOTE DETECTION IN AIR OF HAZARDOUS SUBSTANCES CONTAINING A NITRO GROUP Russian patent published in 2021 - IPC G01N21/64 G01N21/84 

FIELD: quantum electronics.

SUBSTANCE: invention relates to quantum electronics and can be used in development of lidar systems for remote detection in air of low concentrations (ppb-ppm) of vapors and traces of hazardous substances containing a nitro group (for example, high-energy materials, brown gas, saltpeter). Method is based on a method for laser fragmentation of nitro compounds with subsequent laser-induced fluorescence of NO-radicals (LF/LIF). Analyzed region is exposed to radiation of an electric-discharge KrCl laser with wavelength of 222.1 nm and a spectral line width Δλ≈0.4 nm. This provides resonance excitation of optical junctions NO A²Σ⁺(v'=2)←X²P(v''=2) and C²Σ⁺(v'=0)←X²P(v''=4), obtained after photofragmentation of primary molecules and their large characteristic NO₂ fragments. Thereafter, induced fluorescence of NO fragments is recorded on transitions NO A²Σ⁺(v'=2)→X²P(v''=0) and C²Σ⁺(v'=0)→X²P(v''=2) with wave lengths of 205 and 206 nm respectively.

EFFECT: technical result consists in providing the possibility of increasing the sensitivity of the LF/LIF method.

1 cl, 2 dwg