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The U.S. housing market’s quarter two results were disap¬pointing compared with the first quarter. Although overall expected gains did not materialize, certain sectors improved slightly. Housing under construction, completions, and new and existing home sales exhibited slight increases. Overall permit data declined, and the decrease in starts was due primarily to a plunge in multifamily starts. Viewed from a recent historical context, all housing construction subsectors exceeded the record lows recorded in the 2008 to 2011 time period.

Dimension lumber, visually graded in accordance with the National Grading Rule and assigned design values derived in accordance with procedures found in ASTM D 1990, has provided satisfactory performance in homes and other structural applications for many years. This ongoing satisfactory performance depends upon a recognition that all standards are living documents that must change over time as new information becomes available. In fact, since its original approval in 1991, D 1990 has been revised to reflect knowledge gained and the changing needs of the wood products industry. These...

In this chapter, applications of Raman spectroscopy to nanocelluloses and nanocellulose composites are reviewed, and it is shown how use of various techniques in Raman can provide unique information. Some of the most important uses consisted of identification of cellulose nanomaterials, estimation of cellulose crystallinity, study of dispersion of cellulose nanocrystals (CNCs) in polymers, and assessment of CNC/matrix interactions. Further, using a bleached fiber, it was demonstrated that information on the orientation of cellulose at themolecular level can be obtained with the help of...

Copper based waterborne wood preservatives are frequently used to extend the service life of wood products when subjected to frequent moisture exposure. While these copper based treatments protect the wood from fungal decay and insect attack, they increase the corrosion of metals embedded or in contact with the treated wood. Previous research has shown the most plausible corrosion mechanism involves the migration of copper ions from the wood treatment through the wood to the metal surface, where they are then reduced. Despite this, under almost all conditions, copper has not been detected...

Improving the processability and physical properties of sustainable biobased polymers and biobased fillers is essential to preserve its biodegradability and make them suitable for different end user applications. Herein, we report the use of spray-dried lignin-coated cellulose nanocrystals (L-CNCs), a biobased filler, to modify the rheological and thermos-mechanical properties of poly(lactic acid) (PLA) composites. The lignin coating on CNCs not only improved the dispersion but also enhanced their interfacial interaction with the PLA matrix, resulting in a significant improvement in...

Polyacrylonitrile-co-methacrylic acid (PAN-co-MAA) and cellulose nanocrystal (CNC) composite films were produced with up to 40 wt% CNC loading through the solution casting method. The rheological properties of the solution/suspensions and the structural, optical, thermal, and mechanical properties of the resulting films were investigated. The viscosity of the composite suspensions increased with higher CNC loadings and with longer aging times. PAN-co-MAA/CNC films maintained a similar level of optical transparency even with up to 40 wt% CNC loading. The glass transition temperature (Tg)...

This study demonstrates the feasibility of tailored and integrated production of carboxylated cellulose nanocrystals (CNC) with nanofibrils (CNF) from bleached pulp fibers through hydrolysis using a recyclable dicarboxylic acid. Hydrolysis experiments were conducted using ranges of 15–75 wt% maleic acid concentrations, 60–120°C temperatures, and 5–300 min reaction times. Maleic acid esterified cellulose resulted in carboxylated CNC and CNF. Furthermore, the acid-hydrolysis solubilized xylan and depolymerized cellulose, which substantially reduced the energy input for the production of CNF...

Phosphomolybdic acid (PMo12) was used as an electron mediator and proton carrier to mediate biomass pretreatment for ethanol production and electricity generation from wheat straw. In the pretreatment, lignin was oxidized anaerobically by PMo12 with solubilization of a fraction of hemicelluloses, and the PMo12 was simultaneously reduced. In an external liquid flow cell, the reduced PMo12 was re-oxidized with generation of electricity. The effects of several factors on pretreatment were investigated for optimizing the conditions. Enzymatic conversion of cellulose and xylan were about 80%...

To evade endangered timber species laws, unscrupulous importers sometimes attempt to pass protected Dalbergia nigra as look-alike but unprotected, Dalbergia Spruceana. Wood density and fluorescence properties are sometimes used to identify the species. Although these properties are useful and do not require special equipment, they may be less reliable than direct analysis in real time—time of flight mass spectrometry (DART—TOFMS). DART—TOFMS was used to check identities of the D. nigra and D. Spruceana contained in the wood collection of the Forest Products Laboratory (Madison, Wisconsin)....

The goal of this study was to update life-cycle assessment (LCA) data associated with I-joist production in the Pacific Northwest (PNW) region of the United States from cradle-to-gate mill output. The authors collected primary mill data from I-joist production facilities per Consortium on Research for Renewable Industrial Materials (CORRIM) research guidelines. Comparative assertions were not a goal of this study.