ABSTRACT

The prediction of physical (wood density, mass loss) and mechanical (bending properties, compressive strength parallel to grain, and Brinell hardness) properties of heat-treated sessile oak (Quercus petraea L.) by FT-NIR spectroscopy, colour change, and partial least squares regression (PLS) was studied. Samples of oak sapwood and heartwood were treated for 4 h at temperatures at 170, 190, and 210°C. FT-NIR spectra (100 scans and 4 cm⁻¹) and colour parameters (CIE L*a*b* system) were collected on the radial surface before and after heat treatment. The applied heat treatment changed wood properties, darkened the colour and reduced the colour difference between heartwood and sapwood. According to the residual prediction deviation (RPD), most models obtained could be used for preliminary wood quality screening (1.5 < RPD < 2.0) and the properties of heartwood were better predicted than those of sapwood. Mass loss prediction by colour change can be used for quality control while for the other properties FT-NIR provided a more clear picture of the heat-treated oak wood and can serve as a quality indicator.

摘要

通过FT - NIR光谱、颜色变化和研究了偏最小二乘回归（PLS）。橡木边材和心材样品在 170、190 和 210°C 的温度下处理 4 小时。FT-NIR 光谱（100 次扫描和 4 cm ^-1) 和颜色参数（CIE L*a*b* 系统）在热处理前后的径向表面上收集。所应用的热处理改变了木材的特性，使颜色变暗并减少了心边材之间的色差。根据残差预测偏差（RPD），得到的大多数模型可用于初步木材质量筛选（1.5 < RPD < 2.0），心材性能预测优于边材。通过颜色变化预测质量损失可用于质量控制，而对于其他特性，FT-NIR 提供了更清晰的热处理橡木图像，可用作质量指标。