Comparison of methods for multielement analysis of the composition of water aerosol based on spectral analysis of laser plasma
O.A. Bukin1,2, A.Yu. Mayor2,3, D.Yu. Proschenko1,2,3, S.S. Golik2,3, V.V. Lisitsa2,3, D.A. Korovetskiy1,2, A.A. Ilyin2,3
1Admiral G.I. Nevelskoy Maritime State University, Vladivostok, Russia
2Far Eastern Federal University, Vladivostok, Russia
3Institute of Automation and Control Prosesses Far Easten Branch of the Russian Academy of Science, Vladivostok, Russia
Keywords: aerosol, laser spectroscopy, plasma, filamentation, limits of detection
Abstract
Experimental results of comparison of two methods of multielement analysis of liquid-droplet aerosol based on spectral analysis of laser plasma radiation are presented. The features of the emission spectra of laser plasma arising as a result of laser breakdown (LIBS method) and of filamentation (R-FIBS method) in liquid droplet aerosol are investigated. A liquid-drop aerosol containing a Na solution is used. The experiments were carried out to determine the optimal use of the methods on mobile platforms. It is shown that, for both methods, there are optimal delay times of the start of signal registration relative to the start of plasma generation, at which the maximal signal-to-noise ratio is observed. The magnitude of these delays differs by three orders of magnitude when going from nanosecond to femtosecond pulses. For the LIBS method, the dependence of the signal-to-noise ratio was obtained for various focusing of laser radiation deep into the liquid-droplet cloud. The values of the Na limit of detection for both methods are determined.
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