Treesearch

Soft-story wood-frame buildings have been recognized as a disaster preparedness problem for decades. There are tens of thousands of these multi-family three- and four-story structures throughout California and the United States. The majority were constructed between 1920 and 1970, with many being prevalent in the San Francisco Bay Area in California. The NEES Soft project was a five-university multi-industry effort that culminated in a series of full-scale soft-story wood-frame building tests to validate retrofit philosophies proposed by (1) the Federal Emergency Management Agency (FEMA)...

Forest restoration and fire suppression activities in the western United States have resulted in large volumes of low-to-no value residues. An environmental assessment would enable greater use while maintaining environmental sustainability of these residues for energy products. One internationally accepted sustainable metric tool that can assess environmental impacts of new bioenergy conversion systems is the life cycle assessment (LCA). Using the LCA method, this study evaluated the synthesis gas (syngas) electricity produced via a distributed-scale biomass thermochemical conversion...

Nitrogen has been shown to be a limiting nutrient across a range of xylophagous insects. These insects often rely on symbiotic microorganisms in the gut for nitrogen acquisition, via fixation of atmospheric nitrogen or break down of other available nitrogenous substances. In phylogenetically lower, wood-feeding termites, the role of nitrogen fixing bacteria has been well studied. However, there is also evidence that uric acid can be metabolized into ammonia and serve as an additional nitrogen source. In this study, 36 Actinobacterial isolates (Streptomyces spp.) from the guts of Reticuliter...

We report the genome of Postia (Rhodonia) placenta MAD-SB12, a homokaryotic wood decay fungus (Basidiomycota, Polyporales). Intensively studied as a representative brown rot decayer, the gene complement is consistent with the rapid depolymerization of cellulose but not lignin.

Cellulose nanocrystals (CNCs), produced from dissolving wood pulp, were chemically functionalized by transesterification with canola oil fatty acid methyl ester (CME). CME performs as both the reaction reagent and solvent. Transesterified CNC (CNCFE) was characterized for their chemical structure, morphology, crystalline structure, thermal stability, and hydrophobicity. Analysis by Fourier transform infrared (FTIR) and FT-Raman spectroscopies showed that the long chain hydrocarbon structure was successfully grafted onto CNC surfaces. After transesterification the crystal size and crystallin...

In this study, the changes in physical properties and preservative retention of high-grade plywood when subjected to artificial aging processes were examined. The plywood was 15/32-in.-thick panels manufactured from southern yellow pine A and C grades of veneer. The artificial aging processes consisted of three primary mechanisms of degradation: thermal degradation, hydrolysis, and swelling and shrinking stresses. Three aging processes of various severity were used. The least severe was cycled changes in ambient temperature and humidity. The second most severe was cycles of submersion and...

A type of blocked experiment has the potential of being poorly designed and/or analyzed. Verrill (1993, 1999) and Verrill et al. (2004) referred to such an experiment as a “predictor sort” experiment. David and Gunnink (1997) described the procedure as “artificial pairing.” In textbooks it is sometimes referred to as a “matched pair” or a “matched subjects” design. The associated design process is also sometimes described as “forming blocks via a comcomitant variable.” In a wood research context, Warren and Madsen (1977) described the allocation procedure as follows:

This report describes the current state and near-term prospective of the U.S. economy supported by general and statistical information on forest products markets in terms of production, trade, consumption and prices. Market developments are described for sawn softwood, sawn hardwood, softwood log trade, wood-based panels, paper and paperboard, fuelwood, forest product prices, and housing starts. Policy initiatives that can affect domestic markets and international trade in wood products are also discussed in some detail. Data are provided through the end of the year 2015 with estimates for...

Here we demonstrate di-carboxylic acid hydrolysis for the integrated production of lignin containing cellulose nanocrystals (LCNC) and nanofibrils (LCNF) using two unbleached hardwood chemical pulps of lignin contents of 3.9 and 17.2%. Acid hydrolysis experiments used maleic acid solution of 60 wt% concentration at 120°C for 120 min under ambient pressure. Yields of LCNC were low of less than 6% under this set of conditions. The higher lignin content sample produced LCNC with greater height (diameter) of 25 nm but similar length of approximately 230 nm to that from the lower lignin content...

Here we report the unparalleled performance of a novel acid hydrotrope, p-toluenesulfonic acid (p-TsOH) for the rapid and nearly-complete dissolution of wood lignin below the boiling temperature of water. Up to 85% of birch wood lignin can be solubilized at 80° C for 20 minutes. Similar degrees of delignification can only be achieved at 150° C or higher for over 10 hours using known hydrotropes such as aromatic salts, or for 2 hours using alkaline wood pulping. We fractionated mechanically produced birch wood fibers into a carbohydrate-rich water insoluble solid (WIS) fraction and a spent...