Photoacoustic pool capable of performing liquid photoacoustic detection on line and continuously, and measuring method thereof

Abstract

The invention provides a photoacoustic pool capable of performing liquid photoacoustic detection on line and continuously, and a measuring method thereof. The photoacoustic pool comprises a pool body, windows, pressing plates, sealing rings, a liquid inlet, a liquid outlet, a thermometer, a piezoelectric sensor and a photoelectric sensor, wherein the pool body adopts a hollow structure; the internal part of the pool body is used for injecting the measured solution; one window, one sealing ring and one pressing plate are arranged at each of the left end and the right end of the pool body; the liquid inlet and the liquid outlet are formed on the side wall of the pool body respectively; the thermometer is arranged on the side wall of the pool body; the side end of the thermometer is immersed into the measured solution; and the piezoelectric sensor is arranged in the pressing plate at the light outlet end of the photoacoustic pool. Through compensation and correction of the temperature and the light intensity, the influence of the temperature and the light intensity can be obviously reduced, and the measuring precision and the stability can be improved.

Description

technical field [0001] The invention relates to a photoacoustic cell, in particular to a photoacoustic cell capable of continuous on-line photoacoustic detection of liquids and a measurement method. Background technique [0002] Photoacoustic spectroscopy is an important branch of spectroscopy. It is a new method of spectral analysis that integrates the principles and technologies of light, heat, sound, and electricity. Irradiate the substance with a light source or pulsed light source modulated at a certain frequency. When the substance is irradiated by light, the substance is excited by absorbing light energy, and then the absorbed light energy (all or part) is converted into heat through the process of non-radiative elimination of excitation. Periodic light modulation causes this part of the material and its adjacent medium to expand with heat and contract with cold, resulting in periodic changes in stress (or pressure), thus generating an acoustic signal, which is called...

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Problems solved by technology

However, the coupling efficiency between the measured solution and the cuvette and between the cuvette and the piezoelectric sensor is low, resulting in limited measurement sensitivity

Moreover, these methods are only suitable for a single test of static liquids under laboratory conditions, and cannot be applied to online continuous monitoring of various process industries

[0007] On the other hand, for the photoacoustic cell system, the fluctuation of the excitation laser intensity and the change of the temperature of the measured solution will seriously affect the strength of the generated photoacoustic signal, and then affect the final measurement result.

However, the existing liquid photoacoustic cells seldom consider these influencing factors.

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