Treesearch

Two 8-8-coupled sinapic acid dehydrodimers and at least three sinapate-ferulate heterodimers have been identified as saponification products from different insoluble and soluble cereal grain dietary fibers. The two 8-8-disinapates were authenticated by comparison of their GC retention times and mass spectra with authentic dehydrodimers synthesized from methyl or ethyl sinapate using two different single-electron metal oxidant systems. The highest amounts (481 μg/g) were found in wild rice insoluble dietary fiber. Model reactions showed that it is unlikely that the dehydrodisinapates...

Compared to conventional Raman spectroscopy where samples are excited using visible light lasers, 1064 nm-excited FT-Raman technique has the single most important advantage that the sample-fluorescence is significantly suppressed for samples that are strongly fluorescent. DHPs are difficult to analyze in conventional Raman because small amounts of chromophores present in their structures make them highly fluorescent. An FT Raman study of S-, GS-, G-, HG-, and H-DHPs along with two deuterated analogues of G-DHP was carried out with the objectives of understanding the similarities and...

Concerns about indoor air quality due to mold growth have increased dramatically in the United States. In the absence of moisture management, fungicides need to be developed for indoor use to control mold establishment. An ideal fungicide for prevention of indoor mold growth on wood-based materials needs to specifically prevent spore germination and provide long-term protection under conditions of high humidity. Fungicides intended for indoor use must exhibit no mammalian toxicity, be odorless and emit no VOCs. Classes of compounds meeting one or more of these criteria include acids,...

USDA Forest Service analysis finds 104 million tons of woody residuals available for recovery in the U.S., with wood in MSW and C&D debris streams comprising 28 million tons. The U.S. Department of Agriculture Forest Service conducts a variety of analyses to estimate the quantity of woody residuals in the United States. Its Forest Products Laboratory in Madison, Wisconsin does research to estimate the types and amounts generated, and what portion of those tonnages are available for recovery. The data from these analyses are very useful to wood recycling enterprises. They help in identifying...

Recent studies on nondestructive evaluation (NDE) of logs have shown that a longitudinal stress-wave method can be used to nondestructively evaluate the modulus of elasticity (MOE) of logs. A strong relationship has been found between stress-wave MOE and static MOE of logs, but a significant deviation was observed between stress-wave and static values. The objective of this study was to investigate the effect of log diameter on stress-wave evaluation of MOE of logs and to develop a new stress-wave model by relating stress wave MOE to log diameter for static MOE prediction. A total of 201...

Dynamic modulus of elasticity (MOE) of a wood member is defined as the product of its density and square of stress wave speed. The dynamic MOE, which is highly correlated to the static MOE, is commonly used to estimate the load carrying capacity and serviceability of in-situ wood members. The stress wave speed can be estimated using ultrasonic, impact, or vibration techniques. However, nondestructive evaluation of density in place is more difficult than under laboratory conditions. Screw withdrawal resistance, one of the techniques that could be used to estimate the density, was examined...

Extracts of Phanerochaete chrysosporium cultures grown on birch or on a malt extract-peptone-glucose agar medium were analysed by HPLC. A major component from the two sources appears to be identical by HPLC and UV- visible spectrometry. The product isolated from agar-grown cultures was purified to apparent homogeneity and structure analysis by NMR indicates that the metabolite is the beta-resorcylate phanerosporic acid, consistent with previous characterizations. The possible role for the metabolite in wood metabolism is discussed.

The arrangement of anatomical elements in the cross section of a tree can be characterized, at least to a first approximation, with a cylindrical coordinate system. It seems reasonable that the physical properties of wood in the transverse plane, therefore, would exhibit behaviour that is associated with this anatomical alignment. Most of the transverse properties of wood reported in the literature were determined using test specimens with rectilinear geometry. We are interested in using test specimens that are geometrically compatible with the material organization of the tree to avoid...

The fungal resistance of high density polyethylene filled with 50% wood flour was investigated using laboratory soil block tests. Modifications to standard test methods were made to increase initial moisture content, increase exposure surface area, and track moisture content, mechanical properties, and weight loss over the exposure period. Mechanical properties decreased after 12 weeks exposure to Gloeophyllum trabeum and Trametes versicolor. However, irreversible damage due to water sorption made separating the effects of fungal attack and water sorption difficult. When compared on a dry...

Production capacities of all woodpulp mills in the United States are identified by location, ownership, and process type. For each mill, production capacity is reported for the year 2000 by process type; total mill capacities are also reported for 1961, 1965, 1979, 1974, and 1983. In addition, the report summarizes the recent history and current status of woodpulp production capacity in the United States.