Treesearch

Cross-laminated timber (CLT) is a promising wood-based structural component and has potential to provide cost-effective building solutions for residential, commercial and institutional buildings as well as large industrial facilities. Market acceptance of CLT requires that it meets the applicable building code requirements.

Forest materials represent great potential for advancing our goals in the 21st century for sustainable building, energy independence, and carbon sequestration. A critical component of an improved system for producing bioproducts and bioenergr from forest materials is the ability to sort trees, stems, and logs into end-product categories that represent their highest potential values. Nondestructive testing and evaluation technologies have been explored by scientists, engineers, and managers around the world for their ability to assess wood and fiber properties of individual trees, stems,...

Radiocarbon dating of historical and archaeological wood can be complicated, sometimes involving issues of “inbuilt” age in slow-growing woods, and/or the possibility of reuse or long delays between felling and use of the wood. Terminus dates can be provided by dating the sapwood, or the outermost edge of heartwood, while a date from the pith can give an indication of the first years of growth. A sequence of samples from specific points within the bole can be used to determine the growth rate of the tree. Such a combined dating strategy is particularly useful in cross-referencing dates...

Fungi from coarse woody debris samples containing or lacking termites were isolated, and identified from upland and bottomland hardwoods and pines in northeast Mississippi. Samples yielded 860 unique fungal isolates, with 59% identified to genus level. Four phyla, six classes, 10 orders, 14 families, and 50 genera were recovered. The fungal groups encountered by decreasing taxonomic diversity were Imperfect Fungi, Ascomycota, Zygomycota, Basidiomycota, and unknown fungi. The most frequently encountered fungi were Penicillium (81 occurrences), Nodulisporium (57), Cladosporium (37), Trichoder...

Wood protection systems are needed for engineered composite products that are susceptible to moisture and biodeterioration. Protection systems using nano-materials are being developed to enhance the durability of wood-based composites through improved resistance to biodeterioration, reduced environmental impact from chemical leaching, and improved resistance to ultraviolet (UV) degradation. Three approaches will be presented: (1) direct application of nanometals to wood-based products, (2) slow release of biocides embedded in nano-polymer matrices, and (3) controlled delivery of biocides...

Depending on the severity, fire damage can compromise the structural integrity of wood structures such as buildings or residences. Fire damage of wood structures can incorporate several models that address (1) the type, cause, and spread of the fire, (2) the thermal gradients and fire-resistance ratings, and (3) the residual load capacity (Figure 6.1). If there is a danger of local collapse, immediate concerns about the stability of free-standing residual parts of a fire-damaged building will need to be addressed very quickly [1]. Assuming that the structural fire is contained, then under...

Atomic Force Microscopy (AFM) and infrared (IR) spectroscopy have been combined in a single instrument capable of producing 100 nm spatial resolution IR spectra and images. This new capability enables the spectroscopic characterization of biomaterial domains at levels not previously possible. A tunable IR laser source generating pulses on the order of 10 ns was used for excitation of cast sample films or thin cross sections deposited on IR transparent ZnSe prisms. Short duration thermal waves, due to infrared absorption, were studied by monitoring the resulting excitation of the contact...

In this article, we present cradle-to-gate life-cycle inventory (LCI) data for wood fuel pellets manufactured in the Southeast United States. We surveyed commercial pellet manufacturers in 2010, collecting annual production data for 2009. Weighted-average inputs to, and emissions from, the pelletization process were determined. The pellet making unit process was combined with existing LCI data from hardwood flooring residues production, and a life-cycle impact assessment was conducted using the Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts (TRACI) model....

The nonprofit Consortium for Research on Renewable Industrial Materials (CORRIM) has been developing comprehensive environmental performance information on wood building materials consistent with life-cycle standards (http://www.corrim.org/). The articles published in this Special Issue of the Forest Products Journal extend the research by the CORRIM group on the environmental performance of wood products to include the impacts from the uses of wood as a source for bioenergy.

Oxalic acid is a key component in the initiation of brown-rot decay and it has been suggested that it plays multiple roles during the degradation process. Oxalic acid is accumulated to varying degrees among brown-rot fungi; however, details on active regulation are scarce. The accumulation of oxalic acid was measured in this study from wood degraded by the four brown-rot fungi — Gloeophyllum trabeum, Meruliporia incrassata, Coniophora puteana, and Serpula lacrymans — and found to vary significantly. The amount of oxalic acid present was shown to correlate with the mass loss during wood...