Near-infrared measurement method applicable to real-time on-line measuring-point-free temperature compensation

Abstract

The invention relates to a near-infrared measurement method applicable to real-time on-line measuring-point-free temperature compensation. The method comprises the following steps: measuring physical property parameter standard data by utilizing a laboratory method; acquiring the near infrared spectrum of a same sample under different temperature levels; performing preprocessing and principal component analysis on the acquired spectral data, and performing non-separated latent variable modeling on the temperature by using partial least squares so as to acquire a physical property parameter measurement value at the present moment; and acquiring a new spectral data set online, constructing an on-line recursive algorithm, updating the physical property parameter measurement value, and finishing near-infrared on-line measurement capable of achieving a measuring-point-free temperature compensation function. According to the method disclosed by the invention, the temperature serving as a non-separated latent factor variable participates in the near-infrared modeling process, and the recursive algorithm is formed based on the to-be-measured property parameters, so that the property parameter measurement under different temperatures can be finished by virtue of adaptation of the model on the temperature, and direct temperature measurement information and correlation calculation are not needed; and therefore, the established model has the high universality. The on-line recursive algorithm is not sensitive on sample temperature change, and the measurement result has a relatively small integrated error.

Description

technical field [0001] The invention relates to a real-time online measurement method of a near-infrared spectrometer without measuring point temperature compensation, which is suitable for physical parameters affected by ambient temperature, such as fluid viscosity, material density, component concentration, food quality, agricultural product components, drug active component content, On-line real-time detection of gasoline oil quality, etc. Background technique [0002] Near-infrared spectroscopy has become a bright spot in online analytical instruments because of its fast analysis speed, low damage to samples, no chemical pollution, almost suitable for analysis of various samples, and simultaneous determination of multiple components and multiple channels. However, most of the existing near-infrared detection methods are offline measurement. On the one hand, it cannot provide comprehensive and real-time sample information for production and quality inspection departments....

AI Technical Summary

Problems solved by technology

Studies have shown that the change of temperature will cause the shift of vibration spectrum, so that the measurement results of near-infrared spectrum at a specific temperature are only suitable for the analysis of sample quality at this temperature, and the online analysis of sample quality is not ideal. This shortcoming is greatly Limits the application of real-time online measurement technology of near-infrared spectrum analyzer

Images