Treesearch

Wood fromtwovarieties of beetle-killed trees was used to fabricate wood–plastic composites. Loblolly pine and lodgepole pine beetle-killed trees were defibrated mechanically and thermomechanically, respectively, into fiber. Fiber and sawdust produced from the trees were modified with potassium methyl siliconate (PMS) and injection-molded into fiber/sawdust reinforced plastic composites. Modification of fiber and sawdust with PMS improved the compatibility between lignocellulosic materials and ethylene plastic in the composites, resulting in decreased water sorption, increased dimensional...

The movement of firewood within emerald ash borer (Agrilus planipennis Fairmaire) (EAB)-infested states and into adjoining areas has been a contributor to its spread throughout the United States and Canada. In an effort to prevent further human-aided spread of EAB and to facilitate interstate commerce, the USDA Animal and Plant Health Inspection Service and cooperating states in the EAB quarantine have established a heat treatment process to be used as a mitigating treatment to allow movement of firewood from EAB quarantine areas. Firewood producers have since been faced with challenges...

This article reviews five prior commercial wood preservatives that had efficacy concerns. A common factor among all five systems was minimal or no field testing of the proposed system prior to commercialization. Also, the formulation of a successful preservative was twice changed, and one successful system was employed with a new wood species. There is no intent to hold responsible any individual(s), company(ies), or organization(s) for these failures; the purpose is to simply discuss systems which performed less well than expected and report on failure factors. Because it appears that...

Low-rise nonresidential building construction is an important market in Canada for lumber, engineered wood products, structural wood panels, and nonstructural wood panels. This report examines wood products consumption in 2012 for construction of selected low-rise nonresidential buildings types that have six or fewer stories. Buildings with more than six stories are typically severely restricted by building code from being wood framed.

Mountain pine beetle killed lodgepole pine wood chips were pretreated by SPORL (Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses) at 180
C for 25 min and 165
C for 75 min using the same chemical loadings, which represent the same pretreatment severity. The pretreated whole slurries were used to produce lignosulfonate and ethanol through simultaneous enzymatic saccharification and combined fermentation (SSCombF) up to solid loadings of 18% without detoxification. Low temperature pretreatment reduced furan formation, which facilitated ethanol production as measured by...

tComparing analytical results for Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses(SPORL) of Douglas-fir (Pseudotsuga menziesii) at two different temperatures shows that the apparentactivation energy of sugar degradation is higher than that of hemicellulose hydrolysis, approximately161 kJ/mole versus 100 kJ/mole. Thus, one can balance the production of degradation products againsthemicellulose hydrolysis and therefore the enzymatic saccharification efficiency of the resultant sub-strate by changing pretreatment temperature and duration. Specifically, pretreatment at...

A detailed study was undertaken to examine the color and chemistry changes of pine wood flour when its extractives are removed and when it is delignified. The solvent systems employed were toluene/ethanol (TE), acetone/water (AW), and hot-water (HW), while sodium chlorite/acetic acid were used for delignification (i.e., lignin removal (LR)). Samples were analyzed by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, Fourier transform Raman (FT-Raman) spectroscopy, and colorimetry. The study demonstrated that color parameters (i.e., CIE L a b ) were only...

The Wisconsin Department of Transportation (WisDOT) uses wooden posts to support many types of signs along state highways. WisDOT currently uses red pine or Southern Pine posts treated with chromated copper arsenate (CCA) and has generally experienced satisfactory performance and service life. However, there are some areas of concern, as well as potential opportunities for diversifying the wood species and preservatives used. Warp is sometimes a problem with the current pine posts, and increased use of locally sourced wood species for the sign posts could decrease transportation costs and...

The water sorption and mechanical properties of wood-plastic composites (WPCs) made of extracted and delignified wood flour (WF) has been investigated. WF was prepared by extraction with the solvent systems toluene/ethanol (TE), acetone/water (AW), and hot water (HW), and its delignification was conducted by means of sodium chlorite/acetic acid (AA) solution. A 2 4 full-factorial experimental design was employed to determine the effects of treatments and treatment combinations. WPCs were prepared with high-density polyethylene (HDPE) and treated WF was prepared by means of extrusion...

To investigate the effect of extractives and lignin on the thermal stability of wood flour (WF), thermogravimetric analysis was used to determine thermal degradation behavior of extracted and delignified mixed pine WF. The contribution of lignin to thermal stability was greater than that of extractives. Removing extractives resulted in improved thermal stability by increasing onset temperature T0, and solvents with greater polarity contributed more to increasing T0. However, solvent extraction had less effect on decomposition temperature (T2) than did delignification, which significantly...