Quality assessment of heat-treated wood by NIR spectroscopy

摘要

NIR spectroscopy was tested for predicting the properties of heat treated wood using pine (Pinus pinaster) and eucalypt (Eucalyptus globulus) woods with two types of treatment: in oven and in a steam autoclave. Mass loss, equilibrium moisture content, dimensional stability, MOE, bending strength, colour CIELAB parameters and extractives content were determined. NIR spectra were obtained using a fibre probe on the radial surface of the samples. NIR models for mass loss showed very high coefficients of determination (R2) for cross validation ranging from 96–98%. The models obtained for wood properties were in general good with coefficients of determination ranging from 78–95% for equilibrium moisture content, 53–78% for dimensional stability, 47–89% for MOE, 75–77% for bending strength and 84–99%, 52–96% and 66–98% for colour parameters L, a* and b*, respectively. R2 of the models for extractive content varied between 41.9–79.8% for pine and between 35.3–82.2% for eucalypt wood. NIR spectroscopy showed a good potential for quality control and characterization of heat treated woods.