Treesearch

Nanocellulose has potential as a reinforcing agent to improve stiffness and strength in polymer fiber; however, the inherent difference in hydrophilicity makes it challenging to incorporate it into nonhydrophilic polymers, and the composite properties are strongly anisotropic. In the present work, a dual approach was employed to incorporate cellulose nanofibrils (CNFs) into polylactic acid (PLA). Polyethylene glycol (PEG) acted as a compatibilizating agent to enable the melt spinning of CNF/PLA composite fibers without water/solvent, and CNFs were surface modified to improve compatibility,...

We conducted the frst comparative exploration on lignin containing cellulose nanofibril films prepared alternatively from willow bark and wood using a highly recyclable acid hydrotrope, aqueous p-toluenesulfonic acid, as a sustainable means for isolating the nanofibrils. The nanofibrils of willow bark were hydrophobic and produced dense films of high strength under hot pressing. The hydrophobicity resulted from condensation of the residual lignin with low molecular weight aromatic substances of the bark and hydroxymethyl furfural formed in situ from fructose that is also present in the bark.

Syringyl (S) lignin content and the syringyl-to-guaiacyl (S/G) lignin ratio are important characteristics of wood and lignocellulosic biomass. Although numerous methods are available for estimating S lignin units and the S/G ratio, in this work, a new method based on Raman spectroscopy that uses the 370 cm−1 Raman band-area intensity (370-area) was developed. The reliability of the Raman approach for determining S content was first tested by the quantitative analysis of three syringyl lignin models by sampling them, separately, in dioxane and in Avicel. Good linear correlations between the...

Forest residue biomass can be used as bioenergy feedstock, however, issues associated with its properties including low density and high moisture content constrains its valorization. Using mobile conversion technologies that can operate in remote areas and are capable of converting forest residues into high quality energy products can address the issues associated with its valorization for renewable energy production. This study evaluated environmental sustainability of using an integrated novel system of semi-mobile biomass conversion technologies (BCTs) to utilize low-value forest...

Choice and no-choice tests were run to evaluate natural resistance of the woods of two Morus species (Morus alba and Morus nigra) against the subterranean, Heterotermes indicola, under field conditions. Toxicity, antifeedent, and repellency potential of the heartwood extractives was also investigated under laboratory conditions. Heartwood extractives were removed from wood shavings by using methanol or an ethanol: toluene (2:1) mixture. Results of choice and no-choice tests with sap and heartwood blocks exposed to termites, showed that both mulberry species were resistant to termites but...

Lab-sca e structura insu ated pane s (SIPs), using ignin-incorporated rigid po yurethane (RPU) foams as the therma insu ation core, were fabricated and characterized. The RPU foams incorporating surface-modifed ignin were sandwiched between two oriented strand board (OSB) sheets to produce ignin-incorporated SIPs with nomina dimensions of 350×350×46mm3. In comparison to the reference RPU foam without ignin, the ignin-incorporated RPU foams exhibited progressive y higher therma stabi ities coinciding with ignin amount, but simi ar therma conductivity (˜24.5mW·m−1 K−1) and water absorption...

The development and use of tornado shelters have helped reduce loss of human life associated with extreme weather events. Currently, the majority of shelters are built from either steel or concrete. The development of the cross-laminated timber (CLT) industry in the United States has provided an ideal wood product to resist the debris impact and high wind forces associated with tornados. This report overviews the design and development of a residential tornado shelter constructed from CLT. This design was impact- and wind-pressure-tested according to the core requirements of the Internation...

Structural insulated panels (SIPs) have been successfully used in wall and roof construction for years. Combining the strength of facers made of wood structural panels and the energy-efficient core made of foam plastic insulation, SIP walls and roofs are structurally strong and energy-efficient construction systems. However, the data for lateral load performance of most SIP systems have generally remained proprietary and are covered in code evaluation reports held by various SIP manufacturers. The purpose of this project was to develop test data needed to characterize the lateral load...

Established illustrations of juvenile wood in pines depict a central core of wood, varying little by diameter or cambial age, to be nested within mature wood tapering to the upper portion of the stem; alternative illustrations show greater complexity in attributing variability within this central core of wood to its proximity to the crown and/or the maturity of the tree when the wood was formed. The present study addresses the degree to which different representations of juvenile wood are applicable to a sampling of 70-yr-old longleaf pine (Pinus palustris Mill.) trees. Wood property maps...

Maize (Zea mays mays) oil is a rich source of polyunsaturated fatty acids (FAs) and energy, making it a valuable resource for human food, animal feed, and bio-energy. Although this trait has been studied via conventional genome-wide association study (GWAS), the single nucleotide polymorphism (SNP)-trait associations generated by GWAS may miss the underlying associations when traits are based on many genes, each with small effects that can be overshadowed by genetic background and environmental variation. Detecting these SNPs statistically is also limited by the levels set for false...