Method for testing rosin content of pine sawn timber based on time domain nuclear magnetic resonance

Abstract

The invention relates to a method for testing the rosin content of pine sawn timber based on time domain nuclear magnetic resonance. The method is characterized by comprising the steps that a CPMG sequence is used on a time domain nuclear magnetic resonance spectrometer, different-quality standard samples of the vacuum-dried pine sawn timber of a certain tree species are measured, original nuclearmagnetic resonance relaxation attenuation curves of obtained test samples are subjected to inversion calculation to obtain transverse relaxation distribution spectrums of the standard samples, the total area of the transverse relaxation distribution spectral peak of each standard sample is recorded, then the rosin content in the standard samples is determined through a Soxhlet extraction method,a standard curve of the total area of the transverse relaxation distribution spectral peak and the rosin content of the standard samples is established, then the sample with the rosin content to be detected is measured, the obtained total area of the relaxation distribution spectral peak is substituted into the standard curve, the rosin content of the to-be-detected sample is obtained, and then the proportion of the rosin content of the to-be-detected sample can be solved. According to the method, the detecting speed is high, the result is accurate, and a complex chemical solvent extraction experiment is not needed.

Description

technical field [0001] The invention belongs to the field of detection of wood extracts, and is specifically designed to be beneficial to the detection method of rosin content in pine sawn timber. Background technique [0002] According to the data released by the National Forestry and Grassland Administration, the total output value of my country's forestry industry reached 7.1 trillion yuan in 2017. It is initially estimated that the total output value of the timber industry accounts for 40% of the total forestry output value, which is about 3 trillion yuan. After decades of development, my country has become the world's largest wood processing, trade and consumer country, so the wood consumption is huge. At present, the annual domestic wood consumption has exceeded 600 million cubic meters, of which coniferous wood accounts for about 65% of the total. %above. With the gradual advancement of my country's natural forest protection projects, commercial logging of natural for...

AI Technical Summary

Problems solved by technology

However, this method has high requirements for the operator's skills, and the detection process is relatively complicated and takes a long time.

According to the testing standards, ether must be used as the extraction solvent, which is a controlled precursor chemical. Its purchase, use, and storage must strictly comply with the regulations on the management of precursor chemicals of the national public security agency. Therefore, it is difficult for general wood processing enterprises to carry out production. real-time detection

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