Fig. 1. Hammer mill1 and continuous grinder2 usedto prepare the wood. Sources: 1(Hammer Mill Vertica DFZK [GM], BühlerGmbH Germany); 2(KOREAMEDI CO., LTD. Korea).
Fig. 2. Appearance of wood flours treated at different temperatures.
Fig. 3. Micrographs of heat-treated wood flours at different temperatures.
Fig. 4. X-ray diffraction patterns of heat-treated wood samples of different sizes.
Fig. 5. Fourier-transform infrared spectroscopy (FTIR) spectra of 100-mesh heat-treated wood flours at different temperatures.
Table 1. Weight loss of wood flours under different conditions
Table 2. Effect of heat treatment on the crystalline properties of wood samples of different sizes
Table 3. Assignment of the infrared bands to functional groups in wood
Table 4. Assignment of the infrared bands to functional groups in wood (Bodirlau and Teaca., 2009; Dai and Fan, 2011; Wang et al., 2012).
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