Sensitive Detection of Gas-Phase Nitro-Containing Energetic Materials Employing 226-nm Radiation
Abstract
The development of a novel technique for sensing trace vapors of -NO2 containing compounds is reported. This technique is based on the use of one laser operating at 226 nm to both photofragment the target molecule and detect the characteristic NO fragment, formed from a rapid predissociation of NO2 by resonance-enhanced multiphoton ionization (REMPI) and/or laser-induced fluorescence (LIF) via its A2 sum (+)-X2Pi(0,0) band origin. The analytical utility of this technique is demonstrated on a number of compounds, including dimethylnitramine, nitromethane, nitrobenzene, TNT, and RDX, employing molecular beam sampling with time-of-flight mass spectrometric analysis of the jet cooled analyte seeded in an atmosphere of buffer gas. With the present system, limits of detection of 8 and 24 parts-per-billion (ppb) are obtained for RDX and TNT, respectively, using approx. 100 microjoules pulse of laser energy. The limits of detection of the other compounds studied are also presented and discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1993
- Accession Number
- ADA267633
Entities
People
- George W. Lemire
- Josef B. Simeonsson
- Rosario C. Sausa
Organizations
- United States Army Research Laboratory