Treesearch

This study is expanding the previous studies that were focused on the material properties and transportation costs of the two alternative feedstocks for manufacturing wood-plastic composites (WPCs): wood flour and pellets. Besides the material properties and cost analysis, life-cycle assessment (LCA) is equally important to assess the environmental impacts of these two alternative wood feedstocks to manufacture WPCs and gain the knowledge of influences from the manufacturing and transportation processes. The main goal of this study was to compare the environmental impacts from the productio...

Fast growing Eucalyptus grandis W. Hill ex Maiden (EG), E. amplifolia Naudin (EA), Corymbia torelliana (F.Muell.) K.D.Hill & L.A.S.Johnson (CT), and Populus deltoides W.Bartram ex Marshall (PD) may be deployed in Short Rotation Woody Crop (SRWC) systems in the lower Southeastern USA, especially in Florida. To evaluate these species for possible use as medium density fiberboard (MDF) and other composites, 2.5 m logs of three EG clones, three PD clones, six EA progenies, four CT trees, and one P. tremuloides Michx. (PT) tree from northern Wisconsin as a control were characterized for basic...

Energy crops grown on marginal lands offer an alternative supply of renewable resources while avoiding competition with food crops and supporting feed crops. To sustainably grow energy crops, the economic and environmental impacts of various crop management practices such as the adoption of cover crops, fertilization rates, harvesting methods and its end use applications for animal feed or biofuels should be investigated. In this study, we investigated the life cycle analysis (LCA) and economic evaluation of growing two energy crops (energy cane, and napier grass) on the marginal lands...

Biochar produced from low-value forest biomass can provide substantial benefits to ecosystems and mitigate climate change-induced risks such as forest fires. Forest residues from restoration activities and timber harvest and biochar itself are bulky and thus incur high logistic costs, so are considered major bottlenecks for the commercialization of the biochar industry. The objectives of this study were to assess the environmental footprints and techno-economic feasibility of converting forest residues in Pacific Northwest United States into biochar pellets using portable systems followed...

Southern yellow pine specimens collected from historical structures, stumps, and coarse woody debris in forests have been difficult to identify at the species level due to similar wood anatomy. This can be problematic for dendrochronologists when identifying the correct species used in the construction of historical structures, or reconstructing forest history on the landscape and using those specimens in the context of that history. We applied a quadratic discriminant analysis (QDA) to update a century-old method plotting pith diameters against second annual ring diameters to discern one...

To improve the compatibility of an organosolv lignin (OL) in polylactic acid (PLA) blends, a green approach was pursued whereby the lignin was modified with propylene carbonate (PC) to increase its aliphatic hydroxyl content, and thereby, its reactivity. The oxyalkylated organosolv lignin (OOL, synthesized at 170 C) was analyzed by quantitative 31P NMR and showed the number of phenolic hydroxyls decreased from 4.73 to 0.16 mmol g 1 , and the number of aliphatic hydroxyls increased from 3.56 to 3.92 mmol g 1 . OOL-g-PLA copolymer (OOLPC) samples were prepared by graft polymerization of...

Copper is a common component in wood preservatives and is used to protect the wood against fungal degradation. Previous research has shown that the Cu++ oxidation state provides the best wood protection, and Cu++ is widely believed to be the oxidation state of most copper within treated wood. A recent study using X-ray absorption near edge spectroscopy (XANES) reported high amounts of Cu+ in wood that had been in contact with corroded fasteners. This study uses XANES to examine the copper oxidation states in wood treated with several different wood preservatives as a function of time after...

Wood plastic composites (WPCs) specimens containing high-density polyethylene (HDPE) and wood pruning waste were manufactured and evaluated for their mechanical properties. Pecan waste was used as an accessible and sustainable source in this study, and the effects of its particle size and concentration on WPC strengths were evaluated. Pecan waste was milled and sieved to various particle sizes, and testing samples were fabricated by mixing them in a twin-screw extruder and injection molding. A coupling agent was used to create a stable bond between the HDPE and wood. Both tensile...

While it is known that modifying the hydroxyls in wood can improve the decay resistance; what is often missing in the literature is whether these modifications alter wood nanostructure, and how these changes correlate to the improved decay resistance. Here, we used small angle neutron scattering (SANS) to probe the effects of alkylene oxide modifications on wood nanostructure. Southern pine wood samples were chemically modified to various weight percentage gains (WPG) using four different alkylene oxides: propylene oxide (PO), butylene oxide (BO), epichlorohydrin (EpH), and epoxybutene...

This study was aimed at improving the gas barrier property of sugarcane based LLDPE using cellulose nanocrystals (CNCs). Specifically, this study evaluated the effect of CNC content on the crystallinity, tortuosity factor, carbon dioxide permeability (PCO2), and/or oxygen permeability (PO2) of bio-LLDPE sheets and films. All nanocomposites showed considerable improvement in gas barrier irrespective of the CNC content. The PCO2 coefficient of LLDPE sheets decreased by 36% by adding 10 wt% of CNCs into the sheet. Similarly, a significant decline in both PO2 (about 50%) and PCO2 (about 33%)...