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The plans for crashworthy bridge railings for low-volume roads were developed through a cooperative research program involving the USDA Forest Service, Forest Products Laboratory (FPL); the Midwest Roadside Safety Facility, University of Nebraska-Lincoln (MwRSF); and the Forest Service, National Forest System, Engineering. Three railings were developed and successfully tested in accordance with National Cooperative Highway Research Program (NCHRP) Report 350 Test Level-1 requirements. The fourth system was developed for a lower test level based on criteria developed by the Forest Service...

Biopulping is the treatment of wood chips and other lignocellulosic materials with lignin-degrading fungi prior to pulping. Ten years of industry-sponsored research has demonstrated the technical feasibility of the technology for mechanical pulping at a laboratory scale. Two 50-ton outdoor chip pile trials recently conducted at the USDA Forest Service, Forest Products Laboratory (FPL) in Madison, Wisconsin have established the engineering and economical feasibility of the technology. After refining the control and the fungus-treated chips through a thermomechanical pulp (TMP) mill, the...

Stickies continue to represent the most challenging contaminant to remove from recycled secondary fiber. Current projections suggest that pressure sensitive adhesive (PSA) markets will continue to grow rapidly, increasing the concentration of these contaminants in common office-pack wastepaper. PSAas reformulated to exhibit higher removal efficiencies within standard secondary fiber processing equipment are expected to prove effective in alleviating cleanliness demands for the recycling industry. The US Postal Service, in their program to develop postage stamp adhesives that do not...

SouthPro is a Microsoft Excel add-in program that simulates the management, growth, and yield of uneven-aged loblolly pine stands in the Southern United States. The built-in growth model of this program was calibrated from 991 uneven-aged plots in seven states, covering most growing conditions and sites. Stands are described by the number of trees in 13 size classes for softwood, soft hardwood, and hard hardwood species. SouthPro allows managers to predict stand development, by year and for many decades, from a specific initial diameter distribution. Cutting regimes are specified by the...

This review summarizes patents in the area of paper recycling that appeared during the first half of 1998 in either of two on-line data bases: Derwent World Patent Index or Claims/U.S.Patents Abstracts. The information in these data bases is intended to keep readers informed about the latest equipment, chemicals, and technology in this field. The abstracts provide only a brief summary of the inventions. Readers will need to access the full texts of specific patents for complete information. The patents summarized in this review cover a broad spectrum of recycling processes, equipment, and...

The glucose analog 2-deoxyglucose (2-DOG) has been used to obtain mutants derepressed for pentose metabolism. Some researchers have used 2-DOG alone whereas others have used it in the presence of a glucoserepressible carbon source. We examined both methods and screened mutant strains for improved use of xylose in the presence of glucose. Pichia stipitis mutants selected for growth on D-xylose in the presence of 2-DOG used xylose from a 1:1 glucose: xylose mixture more rapidly than did their parents. One of these mutants, FPL-DX26, completely consumed xylose in the presence of glucose and...

In this work, the source of extracellular hydrogen peroxide in cultures of Ceriporiopsis subvermispora was investigated. A thorough search for the presence in the growth medium of oxidases known to be produced by other fungi gave negative results. We therefore explored the prospect that H2O2 might arise from the oxidation of organic acids by MnP. Both oxalate and glyoxylate were found in the extracellular fluid of C. subvermispora grown in salt medium, at concentrations of 2.5 and 0.24 mM, respectively. MnP titers correlated with the mineralization of [14 C]-oxalate in cultures maintained...

We describe here recent methods for quantitative assessment of specific P. chrysosporium mRNAs in organopollutant contaminated soils and in Aspen wood chips. Magnetic capture techniques were used to rapidly purify poly(A)-RNA, and quantitative RT-PCR protocols were developed for all known lignin peroxidase (lip) and cellobiohydrolase (cbh1) genes. The methodology is extremely sensitive and highly specific. Results indicated that gene transcript patterns varied dramatically in response to substrate. In general, transcript patterns in defined media were unreliable predictors of expression in...

The kinetics of Mn3+- oxalate formation and decay were investigated in reactions catalyzed by manganese peroxidase (MnP) from the basiomycete Ceriporiopsis subvermispora in the absence of externally added hydrogen peroxide. A characteristic lag observed in the formation of this complex was shortened by glyoxylate or catalytic amounts of Mn3+ or hydrogen peroxide. MnP titers had a minor effect on this lag and did not influence the decay rate of the complex. In contrast, Mn2+ and oxalate drastically affected maximal concentrations of the Mn3+- oxalate complex formed, the decay of which was...

One-part polyurethane wood adhesives comprise a new class of general purpose consumer products. Manufacturersa claims of waterproof bonds brought many inquiries to the Forest Products Laboratory (FPL) from users constructing aircraft, boats, lawn furniture, and other laminated materials for outdoor use. Although FPL has technical information on several types of polyurethane and isocyanate-based adhesives for wood, no information was available on this new class of adhesives. Four commercial polyurethane adhesives, along with a resorcinol-formaldehyde adhesive to represent a standard of...