Analysis of Aerosol Particles by Resonance Raman Scattering Technique

An analytical technique for aerosol samples which utilizes the resonance Raman effect is described. The aerosol particles were generated at 50 kHz by a vibrating orifice. The nominal particle size was 45 µm in diameter. The visible lines (4579, 4765, 4880, and 5145 Å) of a continuous argon-ion laser were used as the excitation source. Within the coverage of the laser wavelengths, effects of pre-resonance, resonance, and post-resonance Raman scattering were studied. Under the resonance condition, the enhancement of p-nitrosodimethylaniline is 5.5 × 104 when compared to that of nitrate ions. The corresponding concentration of detection limit is 10−6 molar.