Treesearch

Cellulose is the most abundant biopolymer on Earth, found in trees, waste from agricultural crops and other biomass. The fibres that comprise cellulose can be broken down into building blocks, known as fibrillated cellulose, of varying, controllable dimensions that extend to the nanoscale. Fibrillated cellulose is harvested from renewable resources, so its sustainability potential combined with its other functional properties (mechanical, optical, thermal and fluidic, for example) gives this nanomaterial unique technological appeal. Here we explore the use of fibrillated cellulose in the...

The objective of this study is to examine the mechanical performance of cross laminated timber (CLT) panels made of low-value sugar maple under out of plane loads through mechanical tests and numerical simulation. The laminations were sorted into High and Low classes based on the measured modulus of elasticity (MOE). Two 3-layer sugar maple CLT layups as High-Low-High and Low-High-Low glued with resorcinol-based adhesive and one CLT layup of High-Low-High glued with melamine-based adhesive were prepared. Block shear, long-span bending (span-to-depth ratio of 33:1) and short-span bending...

This chapter introduces the Global Forest Products Model (GFPM). The general model structure and the mathematical formulation of the GFPM are provided and key differences and similarities to the modeling approaches developed in the previous chapters are highlighted. The usefulness of the GFPM as a forest sector tool for policy analysis is illustrated by summarizing its applications in a wide array of past and ongoing studies. These studies are summarized under four representative groups: (i) forest sector outlook studies; (ii) studies evaluating the consequences of tariff and non-tariff...

In August, the U.S. housing market was mixed. Assessing the month-over-month data yielded increases for single-family starts and permits, housing under construction, new and existing house sales, and construction spending. On a year-over-year basis, most categories were positive, with the exceptions of multifamily starts, total and multifamily permits, and all completion categories. New house sales continued increasing, recording the largest sales number since 2006. Residential construction spending was positive month-over-month and year-over-year.

In September, most housing indictors were positive. Multifamily housing starts and permits were negative on month-over-month and year-over-year bases. Multifamily housing under construction and new house sales were negative on a month-over-month basis. Housing remains a bright spot for the U.S. economy

Cellulose nanomaterials (CNMs) are a class of materials that have recently garnered attention in felds as varied as structural materials, biomaterials, rheology modifers, construction, paper enhancement, and others. As the principal structural reinforcement of biomass giving wood its mechanical properties, CNM is strong and stif, but also nontoxic, biodegradable, and sustainable with a very large (Gton yr−1 ) source. Unfortunately, due to the relatively young nature of the feld and inherent incompatibility of CNM with most man-made materials in use today, research has tended to be more...

The performance of cellulosic materials is intimately linked to their moisture content. Over the last century, many studies have been devoted to examining the moisture uptake in equilibrium with surrounding environmental conditions. However, with the adoption of automated sorption balances in laboratories worldwide, it has become increasingly popular to study the approach to equilibrium, i.e., sorption kinetics. Recording the moisture content change between two equilibrium states produces a wealth of data, which necessitates a robust methodology for analysis. In this study, we employ...

Loblolly pine is a major fibre source for the pulp and paper industry. Herewe developed the first nonlinear models to predict the within-tree and regional variation of tracheid length and width for planted loblolly pine. Data were obtained from macerated tracheids and near-infrared spectroscopy calibration models from trees sampled in 109 stands across the southeastern United States. The fixed effects for the final tracheid length model, which included cambial age, height of disk within tree, and physiographic region, explained 71 percent of the variation with root mean square error (RMSE)...

Burgundy oil (BO) from Eastern red cedar provides resistance against termites and wood-decay fungi and is enhanced when combined with an amylose inclusion complex (AIC) containing hexadecylammonium chloride (HAC). Indirect evidence also indicated that a methanol Loblolly pine extract (LPE) was inhibitory against termites. This study compared the effects of HAC and didecyldimethylammonium chloride (DDAC) combined with LPE and BO on termites and wood-decay fungi. Southern pine was treated by vacuum/pressure impregnation and resistance evaluated after exposure to termites and decay fungi. The...

Purpose Producing biochar from forest residues can help resolve environmental issues by reducing forest fires and mitigating climate change. However, transportation and storage of biomass to a centralized facility are often cost-prohibitive and a major hurdle for the economic feasibility of producing biobased products, including biochar. The purpose of this study was to evaluate the environmental impacts and economic feasibility of manufacturing biochar from forest residues with small-scale portable production systems. Methods This study evaluated the environmental performance and...