Libs and Raman spectroscopy aerosol online detection device based on single particle

Abstract

The invention relates to a single-particle-based LIBS and Raman spectrum aerosol online detection device, wherein the aerodynamic lens is used to focus the atmospheric aerosol particle sample into a collimated particle beam and screen the particle size, an oscilloscope, two continuous The laser and the corresponding photomultiplier tube together constitute a dual-beam caliper system. The first and second Nd:YAG lasers interact with particles to excite Raman spectroscopy and LIBS spectroscopy respectively. The element composition information in aerosol particles can be detected in real time through LIBS spectroscopy, and the characteristic spectral lines of each element belong to atomic spectral lines without overlapping interference. Raman spectroscopy studies the vibrational and rotational spectra of molecules to obtain structural information on aerosol particles and to obtain information on lattice vibrations of particle samples. The device of the invention is simple and compact in structure, has low requirements on instruments, only needs a low vacuum environment to eliminate background noise interference, and reduces the cost of the detection device. The detection process of the device of the invention is short, and the analysis result can be obtained after a single pulse laser.

Description

technical field [0001] The invention belongs to the field of atmospheric environment detection, and in particular relates to a single-particle-based LIBS and Raman spectrum aerosol online detection device. Background technique [0002] Atmospheric aerosol is a colloidal dispersion system formed by dispersing and suspending small particles of solid or liquid in a gaseous medium. It is flake, needle and other irregular shapes. Aerosol particles come from a wide range of sources, including natural sources such as fine ash and fine dust blown up by the wind, salt particles evaporated from seawater, fallout from volcanic eruptions, and smoke from forest burning, as well as fossil and non-native sources. Anthropogenic sources such as the combustion of fossil fuels, transportation, and smoke emissions from various industrial processes. Because of the wide range of sources, the chemical composition of aerosol is also very complex, which contains various trace metals, inorganic oxi...

AI Technical Summary

Problems solved by technology

[0005] However, in the prior art, single particle technology is mainly used with mass spectrometer (single particle aerosol mass spectrometer). (10 -6 Torr), most of the parts used are imported, and the cost of the instrument is relatively high

In addition, there are still difficulties in the identification of components with the same mass number using mass spectrometry, some spectral peaks may not be accurately judged, and mass spectrometry analysis cannot provide the molecular structure of particulate matter

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