Treesearch

Within the green building fields is a growing movement to recover and reuse building materials in lieu of demolition and land fill disposal. However, they lack life-cycle data to help quantify environmental impacts. This study quantifies the primary energy and greenhouse gas (GHG) emissions released from the production of wood recovered from an old house and from new wood harvested from the forest and produced in a sawmill with both products ending up installed in a new house. In addition, the study quantifies the primary energy and GHG emissions released if the recovered wood is not...

The combination of boric acid (BA) or disodium octaborate tetrahydrate (DOT) and a fatty acid (FA) such as heptanoic, octanoic, and nonanoic acids (C7–C9) is an effective treatment solution for protecting wood structures against mold. BA or DOT alone have substantial potency against insects and decay fungi, but have negligible or no mold inhibitor activity. However, boric acid or DOT combined with a fatty acid either as a dip or vacuum treatment appears to act synergistically to inhibit mold growth. Southern Pine vacuum-treated with BA (or DOT)/FA appears to retain much or all of its...

Hydrolysis experiments with commercial cellulases have been performed to understand the effects of cell wall crystallinity and lignin on the process. In the focus of the paper are loblolly pine wood samples, which were systematically delignified and partly ball-milled, and, for comparison, Whatman CC31 cellulose samples with different crystallinities. In pure cellulose samples, the percentage of cellulose hydrolysis was inversely proportional to the degree of crystallinity. For the loblolly pine samples, the extent of hydrolysis was low for the fraction with 74- to 149- µm particle...

There are numerous examples of wood species that naturally exhibit enhanced performance and longevity in outside exposure independent of preservative treatment. Wood extractives are largely considered to be the contributing factor when evaluating and predicting the performance of a naturally durable wood species. However, little test methodology exists that focuses on the extent of the role of extractives in wood durability. In this study, eight candidate naturally durable wood species plus a nondurable control were evaluated in laboratory soil block tests for resistance to termite attack...

A new cantilever beam apparatus has been developed to measure static and vibrational properties of small and thin samples of wood or composite panels. The apparatus applies a known displacement to a cantilever beam, measures its static load, then releases it into its natural first mode of transverse vibration. Free vibrational tip displacements as a function of time were recorded. This paper compares the test results from the cantilever beam static bending and vibration with standard midpoint simply supported bending samples. Medium density fiberboard panels were obtained from four...

Laboratory mechanical softwood pulps (MSP) and commercial bleached softwood kraft pulps (BSKP) were mechanically fibrillated by stone grinding with a SuperMassColloider®. The extent of fibrillation was evaluated by SEM imaging, water retention value (WRV) and cellulase adsorption. Both lignin content and mechanical treatment significantly affected deconstruction and enzymatic saccharification of fibrillated MSP and BSKP. Fibrillation of MSP and BSKP cell walls occurs rapidly and then levels off; further fibrillation has only limited effect on cell wall breakdown as measured by water...

Standing stress wave measurements were taken on 274 small-diameter Douglas-fir trees in western Montana. Stand, site, and soil measurements collected in the field and remotely through geographical information system (GIS) data layers were used to model dynamic modulus of elasticity (DMOE) in those trees. The best fit linear model developed resulted in an adjusted R2 = 0.52 for predictions of individual tree DMOE and an R2 = 0.85 for predictions averaged on a stand basis. The linear model used was mean annual increment1, total tree height, and a GIS-based estimate of soil bulk density....

Whereas climate change mitigation involving payments to forest landowners for accumulating carbon on their land may increase carbon stored in forests, it will also affect timber supply and prices. This study estimated the effect on US timber and primary forest product markets of hypothetical timber set-aside scenarios where US forest landowners would be paid to forego timber harvests for 100 years to increase carbon storage on US timberland. The scenarios featured payments to landowners of $0 (business-as-usual (BAU)), $10, and $15 per each additional metric ton (t) of carbon dioxide...

Rejects from sulfite pulp mill that otherwise would be disposed of by incineration were converted to ethanol by a combined physical–biological process that was comprised of physical refining and simultaneous saccharification and fermentation (SSF). The energy efficiency was evaluated with comparison to thermochemically pretreated biomass, such as those pretreated by dilute acid (DA) and sulfite pretreatment to overcome recalcitrance of lignocelluloses (SPORL). It was observed that the structure deconstruction of rejects by physical refining was indispensable to effective bioconversion but...

The distribution of poly(acrylic acid) (PAA) in model laminates of nanocellulose and poly(vinyl alcohol) (PVOH) was investigated by FTIR chemical imaging. The method was effective in spatially discerning the three components of the composite. PAA can potentially improve the performance of nanocellulose reinforced PVOH by not only crosslinking the PVOH matrix but also improving the adhesion between PVOH and nanocellulose by forming ester linkages with both of them. However, PAA was found to migrate out of the PVOH matrix and concentrate in the nanocellulose layer of the laminate. This led...