Potential of X-ray computed tomography for 3D anatomical analysis and microdensitometrical assessment in wood research with focus on wood modification

Abstract

Potential of X-ray computed tomography for 3D anatomical analysis and microdensitometrical assessment in wood research with focus on wood modification. International Wood Products Journal, 4(3), pp. 183-190. The potential of X-ray computed tomography for 3D anatomical analysis and microdensitometrical assessment in wood research with focus on wood modification ABSTRACTStudying structure and chemistry of wood and wood-based materials is the backbone of all wood research and many techniques are at hand to do so. A very valuable modality is X-ray CT, able to non-destructively probe the three-dimensional structure and composition. In this paper we elaborate on the use of Nanowood, a flexible multiresolution X-ray computed tomography (X-ray CT) setup developed at UGCT, the Ghent University Centre for X-ray Tomography. The technique has been used successfully in many different fields of wood science. It is illustrated how 3D structural and microdensitometrical data can be obtained using different scan set-ups and protocols. Its potential for the analysis of modified wood is exemplified, a.o. for the assessment of wood treated with hydrophobing agents, localisation of modification agents, pathway analysis related to functional tissues, dimensional changes due to thermal treatment, etc. Furthermore, monitoring of transient processes is a promising field of activity too.

Residual Brewer’s Yeast Biomass and Bacterial Cellulose as an Alternative to Toxic Phenol-Formaldehyde Binders in Production of Pressed Materials from Waste Wood

“…This is probably due to the fact that press-mass was less homogeneous and spread poorly. Zhang et al (2011) and van den Bulcke et al (2013) also showed that the heterogeneity of pressed boards and their poor quality is associated with viscosity and with the ratio of the main component to a binder.…”

“…A peak at 1650 cm -1 is caused by adsorption of OH-groups and conjugated C-O bonds or carbonyl and carboxyl groups in the lignin (Pandey and Pitman 2003). A peak at 1560 cm -1 is caused by skeletal vibrations of the aromatic ring (Roeges and Noel 1995), and at 1089 cm -1 the peak is caused by stretching vibrations of C-O bonds characteristic for the primary, secondary, and tertiary hydroxyl groups in the lignin (Bazarnova et al 2002).…”

“…According to the literature, the absorption at 3620 cm -1 is caused by stretching vibrations of OH-groups not connected by hydrogen bonds; at 3600 to 3000 cm -1 , the absorption is caused by stretching vibrations of OH-groups involved in hydrogen bonds in cellulose, lignin, and hemicellulose (Bazarnova et al 2002;Fengel and Wegener2003).…”

“…In the area of 2920 cm -1 to 2850 cm -1 , the absorption is caused by CH-stretching vibrations of methyl and methylene groups in lignin, and at 1770 cm -1 the absorption is caused by C=O vibrations in the ester group of hemicelluloses (Fengel and Wegener 1989;Bazarnova et al 2002;Fengel and Wegener2003) and uronic acids (Bazarnova et al 2002;Muller et al 2009). A peak at 1650 cm -1 is caused by adsorption of OH-groups and conjugated C-O bonds or carbonyl and carboxyl groups in the lignin (Pandey and Pitman 2003).…”

“…An intermediate product was formed in this process, i.e., dialdehyde cellulose with an absorption band (crystallinity strip) with a maximum frequency of 1392 cm -1 , corresponding to scissor vibrations of the methylene group, C1 atom vibrations, and vibrations of four atoms in the p-glycosidic structures surrounding C1. The absorption at 1650 cm -1 spectra of unmodified cellulose was caused by adsorbed water (Bazarnova et al 2002;Yin et al 2009;Kristiansen et al 2010;Tlupova et al 2012).…”