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Building products have come under increased scrutiny because of environmental impacts from their manufacturing. However, environmental impacts of manufacturing some wood products—such as prefinished engineered wood flooring—have not been determined. This study examined prefinished engineered wood flooring in the eastern United States following the life-cycle inventory approach. To provide a reference to the product system inputs and outputs, a functional unit of one cubic meter of prefinished engineered wood flooring was selected. This study surveyed five engineered wood flooring manufactur...

This chapter will consider the basic aspects and findings of several forms of NMR spectroscopy, including separate discussions of proton, carbon, heteronuclear, and multidimensional NMR. Enhanced focus will be on 13C NMR, because of its qualitative and quantitative importance, followed by NMR’s contributions to our understanding of lignin structure by topic rather than by the type of NMR experiment. The more recent availability of lignin-biosynthetic-pathway mutant and transgenic plants has greatly aided the NMR analysis of perturbed and normal lignins, providing deeper insights into the...

Three pulp mills in North America using 50% hydrogen peroxide have suffered explosions of pumps, mixers, and tanks. In two instances, alkali-catalyzed decomposition of peroxide is implicated in the explosion. Although many mechanical pulping facilities use hydrogen peroxide to bleach pulp, no &-catalyzed explosions have been reported. This research uses a kinetic model of peroxide decomposition to explain why the peroxide bleaching process used for mechanical pulps has lower than processes used to bleach chemical pulps.

The disposal of forest-thinning residue is one of the major problems for sustainable forest management. The purpose of this study was to investigate the technical possibility of utilizing aspen logging slash wood with a diameter ranging from 50 to 76 mm for flakeboard production. Influences of weight ratio between slash wood and commercial flakes on the selected mechanical and physical properties of panels were examined. The need of an extra debarking process for panel fabrication was also evaluated. The results indicated the modulus of elasticity (MOE), modulus of rupture (MOR), internal...

In this work glycosyl hydrolase (GH) family 30 (GH30) is analyzed and shown to consist of its currently classified member sequences as well as several homologous sequence groups currently assigned within family GH5. A large scale amino acid sequence alignment and a phylogenetic tree were generated and GH30 groups and subgroups were designated. A partial rearrangement in the GH30 defining side-associated β-domain contributes to the differentiation of two major groups that contain up to eight subgroups. For this CAZy family of Clan A enzymes the dual domain fold is conserved, suggesting that...

Uncertainties in the basic structures of especially lignin but also other components in lignocellulose make fungal biodegradation studies a challenging task. The following properties are important in terms of microbial or enzymatic attack: (1) lignin polymers have compact structures that are insoluble in water and difficult to penetrate by microbes or enzymes, (2) the intermonomeric linkages that account for the rigidity of lignin comprise many kinds of C–C and C–O bonds with the β-aryl ether linkage being the most significant and (3) intermonomeric linkages in lignin are not hydrolyzable....

In this study, wood specimens were coated with water-borne silsesquioxane oligomers by an in situ sol-gel deposition process. The effect of these water-borne sol-gel thin films on weathering characteristics and moisture-uptake properties of the wood specimens were investigated. The weathering characteristics were investigated by exposure of the specimens to artificial weathering conditions in a Weather-Ometer™. Water vapor uptake properties were determined by equilibrating the specimens in controlled humidity chambers, and liquid water uptake properties were determined by immersing the...

In recent years, a new type of nanocomposite – cellulose based hybrid nanocomposites, which adopts cellulose nanofibers as matrices, has been intensively developed. Among these materials, hybrid nanocomposites consisting of cellulosic fibers and magnetic nanoparticles have recently attracted much attention due to their potential novel applications in biomedicine, textronics, security papermaking and packaging. The incorporation of the magnetic nanoparticles, e.g. Fe3O4 magnetites, which possess controllable collective magnetic properties, enables new functionalities that are impossible...

Blends of polyethylene (PE) and polypropylene (PP) could potentially be used as matrices for wood–plastic composites (WPCs). The mechanical performance and morphology of both the unfilled blends and wood-filled composites with various elastomers and coupling agents were investigated. Blending of the plastics resulted in either small domains of the minor phase in a matrix of major phase or a co-continuous morphology if equal amounts of HDPE and PP were added. The tensile moduli and yield properties of the blends were clearly proportional to the relative amounts of HDPE and PP in the blends....

Performance attributes of a home, constructed in 2001 in Madison, WI, on a treated-wood foundation system were investigated over a multiyear period. Temperature conditions in the basement of the building were, without exception, comfortable, even though the basement was not provided with supply registers for heating or cooling. Basement humidity conditions were acceptable (although not ideal), even though dedicated dehumidification equipment was not used in the building. The basement zone did not develop any perceptible smell of mold. No visible mold growth occurred on surfaces in the...