Temperature compensation method for detecting oxygen concentration in glass bottle through wavelength modulation spectroscopy

Abstract

The invention discloses a temperature compensation method for detecting the oxygen concentration in a glass bottle through wavelength modulation spectroscopy. The temperature compensation method comprises the following steps: firstly, collecting secondary harmonic and field temperature data of a sample to be detected under conditions of fixed air pressure and temperature in the bottle; secondly, carrying out data pre-processing on the secondary harmonic of the sample to be detected; conveying the pre-processed data into an oxygen concentration inversion model to obtain a direct predicated value N0; substituting the temperature data which is acquired in situ into a temperature calibration function f(T), and obtaining a temperature correction factor k; calculating according to a formula Nc=kN0 to obtain an actual oxygen concentration value Nc after temperature correction. The temperature compensation method provided by the invention has the beneficial effects that corresponding temperature correction factors are obtained through introducing the temperature calibration function and the temperature correction factors are directly multiplied by a result of direct concentration inversion prediction, so that the corrected oxygen concentration in the current bottle is obtained, and inhibition of temperature changes is realized; the predication precision of the oxygen concentration in the glass bottle can be effectively improved.

Description

technical field [0001] The invention relates to the technical field of gas detection, in particular to a temperature compensation method for detecting the oxygen concentration in a glass bottle by wavelength modulation spectrum mainly used for modeling and prediction of the oxygen concentration in the glass bottle. Background technique [0002] In the pharmaceutical industry, the oxygen concentration in the sealed glass medicine bottle directly determines the oxidation rate of the drug and affects the shelf life. At present, except for a very small number of pharmaceutical companies in my country that have introduced foreign advanced testing equipment for online testing, other companies are using gas chromatography. Chemical principles or magnetic oxygen analysis and other methods and means for sampling testing. With the development of semiconductor lasers, wavelength modulation spectroscopy (WMS) technology has been used in industrial processes to monitor gas temperature, pr...

AI Technical Summary

Problems solved by technology

[0003] However, the change of temperature will cause the force between molecules inside the gas to change, which will change the transition of molecules between different energy levels, thus affecting the absorption spectrum of molecules

Specifically, changes in temperature will affect the absorption line intensity of the gas, the full width at half maximum of the absorption line shape, and the number density of gas molecules, etc., which will destroy the conditions for inversion of the gas concentration by the second harmonic eigenvalues, thereby reducing the detection accuracy. decline

Images