Treesearch

Automated grading machines that quantify knots are increasingly deployed by lumber mills, however their use in mill studies that assess lumber quality have been limited. The objective here was to develop a method to evaluate the knots of loblolly pine lumber using image analysis and to develop models to predict modulus of elasticity (MOE) and modulus of rupture (MOR) from 171 pieces of dimension lumber. Lumber was photographed on the wide faces and individual knots were identifed using the k-means clustering algorithm. The percentage of wood made up of knots on the wide faces (Knot%) was...

Water vapor sorption is the most fundamental aspect of wood-moisture relations. It is directly or indirectly related to the physical properties of wood and the onset of wood-damage mechanisms. While sorption properties of cellulosic materials have been utilized since antiquity, the time-dependent transition from one moisture content to another (i.e., sorption kinetics) has received much less attention. In this critical review, we present the state-of-the-art of water vapor sorption kinetics in wood. We first examine different experimental methods that have been used to measure sorption...

Mechanically fibrillated cellulose nanofibril (CNF) sheets of varying thicknesses were fabricated by using a wet stacking lamination technique without the use of solvents other than water or binders. The use of this technique allowed for the creation of multilayer structures with a working area of 117 mm by 117 mm and thickness of up to 0.547 ± 0.03 mm in under 2 h, which represents the shortest total processing time reported for such thickness of CNF sheets. To highlight the capabilities of utilizing wet stacking, the thickest reported 100% pure multilayer CNF sheet with a thickness of...

To avoid the use of toxic synthetic chemicals due to their potential environmental impacts, the feasibility of using heartwood extracts of Tectona grandis and Cedrus deodara as wood preservatives against the subterranean termite, Reticulitermes favipes and two basidiomycete decay fungi, Trametes versicolor and Rhodonia placenta, was investigated in laboratory experiments. There were no signifcant diferences in feeding for R. favipes fed solvent-extracted and non-extracted T. grandis in choice and no-choice tests with 100% mortality. Reticulitermes favipes ignored non-extracted C. deodara...

The future bioeconomy depends on the increased utilization of renewable lignocellulosic resources from trees and other bioenergy crops. However, considering that the diffusion of ions, chemicals, and enzymes into secondary cell walls is critical to effectively utilize lignocellulosic biomass, the unidentified mechanisms underpinning this diffusion have hindered progress. Here, nanomechanical spectroscopy was used to measure changes in moisture-dependent relaxations of amorphous polysaccharides inside loblolly pine (Pinus taeda) cell wall layers. The comparison with recent ion mobility...

As technology has evolved, bat researchers have relied more heavily on using acoustic techniques to collect data on bat communities. Acoustic data can be collected actively, where the researcher is present at the sampling point and follows the bat with the detector, or passively, where the researcher is not present and the detector is set out by itself. Active sampling can yield longer, clearer calls, and is only conducted during part of the night (usually from sunset to about 02:00 hours) for short bouts (20 minutes). By contrast, passive sampling can yield lower quality calls, but...

Although molecular-scale wood-water interactions needed for moisture-durability can lead to the accelerated development of moisture-durable products, these interactions are often experimentally elusive. In this perspective, the topic’s state of the art understanding will be discussed, excluding computational work. Recent research efforts based on infrared spectroscopy methods have provided new insights in terms of the accessibility of the wood polymers and moisture-induced polymer dynamics. Likewise, neutron scattering and nuclear magnetic relaxometry experiments have shown that bound...

Disease dynamics are governed by variation of individuals, species, and environmental conditions across space and time. In some cases, an alternate reservoir host amplifies pathogen loads and drives disease transmission to less competent hosts in a process called pathogen spillover. Spillover is frequently associated with multi‐host disease systems where a single species is more tolerant of infection and more competent in pathogen transmission compared to other hosts. Pathogen spillover must be driven by biotic factors, including host and community characteristics, yet biotic factors...

This review is a summary of the Raman spectroscopy applications made over the last 10 years in the feld of cellulose and lignocellulose materials. This paper functions as a status report on the kinds of information that can be generated by applying Raman spectroscopy. The information in the review is taken from the published papers and author’s own research—most of which is in print. Although, at the molecular level, focus of the investigations has been on cellulose and lignin, hemicelluloses have also received some attention. The progress over the last decade in applying Raman spectroscopy...

Context. Landscape ecology was founded on the idea that there is a reciprocal relationship between spatial pattern and ecological processes. I provide a retrospective look at how the state-of-the-art of landscape pattern analysis has changed since 1998. Objectives. My objective is to show how pattern analysis techniques have evolved and identify some of the key lessons learned. Results. The state-of-the-art in 1998 was derived from information theory, fractal geometry, percolation theory, hierarchy theory and graph theory, relying heavily on the island-patch conceptual model using categoric...