Glow discharge-based plasma generator and spectrum detection system formed by same

Abstract

The invention discloses a glow discharge-based plasma generator and a spectrum detection system formed by the glow discharge-based plasma generator; the spectrum detection system mainly comprises a sampling system, a power supply, the plasma generator, an optical detection system and a data processing system, wherein the plasma generator mainly comprises two discharge electrodes, and a working gas inlet cavity, a discharge cavity and a cushion chamber which are arranged in an insulation material generation device body and are sequentially communicated; the working gas inlet cavity has a pipe cavity structure; the side of the discharge cavity vertical to the working gas inlet direction has an open structure; the two discharge electrodes are oppositely arranged at the two sides along the other direction of the discharge cavity; the side of the cushion chamber facing the working gas inlet direction is a closed surface; the working gas enters through the gas inlet cavity, is ionized by the discharge cavity arranged between the two discharge electrodes and then is discharged outside from an opening of the discharge cavity; the glow discharge-based plasma generator is simple in structure, small in volume, low in power and low in gas consumption, and has the tendency of being developed into portable equipment.

Description

Technical field [0001] The invention belongs to the field of analytical chemical spectrum analysis, and in particular relates to a glow discharge-based plasma generator and a plasma excitation spectrum detection system composed of it, which can be applied to the analysis and detection of organic and inorganic substances. Background technique [0002] The emission spectroscopic detection method is to use the characteristic spectral lines and their intensities generated during the excitation and transition of the substance to realize the detection of the composition and content of the substance. At present, the excitation light sources commonly used in the emission spectroscopy detection method mainly include DC arc, low-voltage AC arc, high-voltage capacitor spark and inductively coupled high-frequency plasma source. However, these excitation light sources are bulky, high in power, and high in detection cost, making it difficult to realize miniaturization and portability, and...

AI Technical Summary

Problems solved by technology

This type of plasma generating device increases the gas consumption during the plasma blowing process, which is not conducive to the portability of the device, and the contact between the plasma and the discharge chamber may easily cause the collision of the active material and the discharge chamber to cause spectral Signal loss, which also affects the stability of the plasma

Moreover, the increase of the maintenance gas flow rate shortens the retention time of the active species in the plasma, which reduces the sensitivity.

The detection light emitted by the second type of atmospheric pressure glow discharge plasma generator passes through the wall of the plasma discharge chamber (transparent material such as quartz or glass) and is then collected by the optical fiber. In the process, carbon is deposited on the wall of the discharge chamber, which affects the transmission of light, thus weakening the detection signal

In short, the plasma emitted by the atmospheric pressure glow discharge plasma generating device of the prior art still has problems such as poor stability, large gas consumption, short service life, and low sensitivity as an excitation light source. These unfavorable factors limit the use of atmospheric pressure glow discharge plasma. Application of Excitation Light Source in Portable Instruments and in Practical Detection

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