Treesearch

This paper presents analysis of a 3-dimensional engineered structural panel (3DESP) having a tri-axial core structure made from phenolic impregnated laminated-paper composites with and without high strength composite carbon-fiber fabric laminated to the outside of both faces. Both I-beam equations and finite element method were used to analyze four-point bending of the panels. Comparisons were made with experimental panels. In this study, four experimental panels were fabricated and analyzed to determine the influence of the carbon-fiber on bending performance. The materials properties for...

Of the recently developed univariate and multivariate near-IR FT-Raman methods for estimating cellulose crystallinity, the former method was applied to a variety of lignocelluloses: softwoods, hardwoods, wood pulps, and agricultural residues/fibers. The effect of autofluorescence on the crystallinity estimation was minimized by solvent extraction or chemical treatment or both. Additionally, when the roles of lignin and hemicellulose in the Raman crystallinity assessment were investigated, it was found that syringyl lignin containing lignocelluloses generated somewhat higher crystallinity,...

The goal of the study was to conduct a life-cycle inventory (LCI) of California redwood (Sequoia sempervirens) decking that would quantify the critical environmental impacts of decking from cradle to grave. Using that LCI data, a life-cycle assessment (LCA) was produced for redwood decking. The results were used to compare the environmental footprint of redwood decking to other decking materials that serve an equivalent function. The other materials examined include plastic (cellular PVC) and wood–plastic composites (WPCs) with recycled content varying from 0% and 100%.

Bamboo is a type of biomass material and has great potential as a bioenergy resource for the future in China. Surface chemical and thermal–mechanical behavior play an important role in the manufacturing process of bamboo composites and pellets. In this study, moso bamboo was treated by sodium hydrate solution and acetic acid solution. Surface chemical and dynamic mechanical properties of bamboo were determined using Fourier transform infrared spectroscopy and dynamic mechanical thermal analysis, respectively. Results showed that the main polar chemical groups of the outer layer of bamboo...

Wood specific gravity (SG) is one of the most important variables used to determine biomass. Measurement of SG is problematic because it requires tedious, and often difficult, sampling of wood from standing trees. Sampling is complicated because the SG usually varies nonrandomly within trees, resulting in systematic errors. Off-center pith and hollow or decayed stems pose further problems in biomass estimation. When the pattern of variation within a tree is known, as it often is for a given species, the sampling procedure can be greatly simplified by sampling wood that approximates a mean...

More than 1,500 covered bridges remain in the United States. They are a unique part of our history; thus, replacement of bridge components is an equally important part of preserving this uncommon style of craftsmanship. The goal of this project was to evaluate seven wood species for their durability in above-ground field exposure. Chemical analysis was also conducted using gas chromatography–mass spectrometry (GS–MS) for fatty acids and terpenoids in an attempt to correlate extractive content with durability. Extracts removed from the durable wood species were also tested in laboratory...

This report presents annual data but is published every 2 years. The data present current and historical information on the production, trade, consumption, and prices of timber products in the United States. The report focuses on national statistics, but includes some data for individual states and regions and for Canada. The data were collected from industry trade associations and government agencies. They are intended for use by forest land managers, forest industries, trade associations, forestry schools, renewable resource organizations, individuals in the major timber producing and...

The aim of this study is determine the relative sensitivity of a panel of seven polyhydroxyalkanoate producing bacteria to a panel of seven lignocellulosic-derived fermentation inhibitors representing aliphatic acids, furans and phenolics. A further aim was to measure the polyhydroxybutyrate production of select organisms on lignocellulosic-derived monosaccharides arabinose, xylose, glucose and mannose.

Various cellulose nanofibrils (CNFs) created by refining and microfluidization, in combination withenzymatic or 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidized pretreatment were compared. Themorphological properties, degree of polymerization, and crystallinity for the obtained nanofibrils, aswell as physical and mechanical properties of the corresponding films were evaluated. Compared torefining, intense microfluidization contributed greater separation of nanofibril bundles, which led to anenhancement of mechanical strength and transparency for the resultant film. The selected...

Research and development of the renewable nanomaterial cellulose nanofibrils (CNFs) has received considerable attention. The effect of drying on the surface energy of CNFs was investigated. Samples of nanofibrillated cellulose (NFC) and cellulose nanocrystals (CNC) were each subjected to four separate drying methods: air-drying, freeze-drying, spray-drying, and supercritical-drying. The surface morphology of the dried CNFs was examined using a scanning electron microscope. The surface energy of the dried CNFs was determined using inverse gas chromatography at infinite dilution and column...