Single-particle detection system based on Raman and laser-induced breakdown spectroscopy integration

Abstract

The invention discloses a single-particle detection system based on Raman and laser-induced breakdown spectroscopy integration. The single-particle detection system comprises an objective table, an illumination unit, a microscopic imaging unit, a Raman detection unit and a laser-induced breakdown spectroscopy detection unit. Single particles are placed on the objective table, the positions of thesingle particles can be precisely adjusted in a two-dimensional mode, and the microscopic imaging unit collects images of the single particles. The Raman detection unit comprises a continuous operation laser device and a first spectrograph, the continuous operation laser device irradiates the surfaces of the single particles, excites the vibration mode of molecules contained in the single particles and generates scattered photons with the frequency different from that of the exciting light, and the first spectrograph records a Raman scattering spectrum to analyze molecular information of the single particles. The laser-induced breakdown spectroscopy detection unit comprises a pulse laser and a second spectrograph, the pulse laser generates high-energy nanosecond pulses, and a high-intensity electric field of the pulse laser instantly ionizes particles to be detected and generates plasma to emit light; and the second spectrograph is used for detecting plasma luminescence and analyzing the element components of the to-be-detected single particles.

Description

technical field [0001] The invention relates to the field of single particle detection, in particular to a single particle detection system based on the integration of Raman spectroscopy and laser-induced breakdown spectroscopy. Background technique [0002] In recent years, the rapid development of my country's modern industrialization level has not only improved the living standards of our people, but also brought negative effects such as air pollution. The concentration of suspended particulate matter in the atmosphere is usually used as one of the important indicators of pollution severity. Suspended particulate matter mainly comes from many factors such as daily power generation, industrial production, and vehicle exhaust emissions, and its formation mechanism is relatively complicated. As an important source of pollution, suspended particles (suspended particles with a particle diameter not greater than 75 μm) have seriously polluted the atmospheric environment and af...

AI Technical Summary

Problems solved by technology

Single particle aerosol mass spectrometer (SPMS) is a relatively common single particle detection device, which can chemically analyze single particles, but due to the inconsistent energy distribution of the laser used for detection in the device, when particles are ionized at different positions of the laser , the difference between the same particles is very large, which will lead to poor repeatability of spectrogram detection

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