The biomorphic Silicon Carbide (BioSiC) ceramic with highly interconnected porous three-dimensional (3D) structure was fabricated by utilizing balsa wood cellulose nanofibers aerogel as the biotemplate and polycarbosilane (PCS) as the preceramic precursor. Evolution of morphology, composition, and pore properties from untreated wood to porous BioSiC was investigated systemically. The shrinkage and weight gain during pyrolysis was discussed. It was found that the structure of as-synthesized BioSiC was related to the microstructure of wood aerogel template and the concentration of PCS precursor. The proper microstructure of cellulose skeleton which was essential for the infiltration process could obtained by removing lignin and hemicellulose appropriately. The optimum PCS content was 40 wt. % for easy infiltration and proper SiC content. The results revealed that the dredged skeleton of cellulose was reproduced perfectly by PCS ceramization. The obtained BioSiC presented high porosity (61.03%) and low density (0.86 g/cm³) with good Darcy permeability (19.22 mD).

Chromophore structures in wood are the core elements for regulating wood color. Thermal treatment can regulate the color of wood, thus increasing its added value. In this study, conventional thermal treatment was used to regulate the color of Eucalyptus, in order to make its color close to the precious wood species Burma padauk. The color change in Eucalyptus wood was analyzed using the chromaticity index and UV–Vis. The chromophore structures in the treated wood and their discoloration mechanisms were characterized via FTIR, XPS, NMR, etc. The results showed that the color of eucalyptus could be regulated via thermal treatment to become more similar to the color of Burma padauk under both saturated steam and hot air. The treated wood showed a color difference in the 400~500 nm region in spectral absorption. The changes in the chromophore structures of wood were accompanied by the degradation of hemicelluloses. Meanwhile, demethoxylation occurred in the syringyl structure G of lignin, which led to the polymerization of lignin and decreased the lightness value of wood. Moreover, the number of conjugated structures in the chromophore groups increased, which caused the color of the wood to tend toward red. This study provides a reference for the color regulation of wood, and the mechanisms are also discussed.