Treesearch

Stress wave nondestructive evaluation (NDE) technologies are being used in our laboratory to evaluate the performance properties of engineered wood. These techniques have proven useful in the inspection of timber structures to locate internal voids and decayed or deteriorated areas in large timbers. But no information exists concerning NDE and important properties of wood composites exposed to decay fungi. For our pilot study on several types of wood composites, we examined the relationship between nondestructive stress wave transmission, decay rate and the bending properties of OSB...

The recent sequencing of the Phanerochaete chrysosporium genome presents many opportunities, including the possibility of rapidly correlating specific wood decay proteins of the fungus with the corresponding gene sequences. Here we compare mass fragments of trypsin digests, determined by MALDI-MS (Matrix Assisted Laser Desorption Ionization-Mass Spectrometry), with predicted mass fragments derived from genome sequence. Glyoxal oxidase of P. chrysosporium is used for proof of concept because its genomic organization is known. Glyoxal oxidase was also chosen because it is a glycoprotein, as...

We examined the major bark beetles and associated fungi colonizing subcortical tissues of white spruce (Picea glauca (Moench) Voss) in the Great Lakes region. Trees were felled at one northwestern Wisconsin site in a preliminary study in 1997 and at 10 sites throughout northern Wisconsin, Minnesota, and Michigan in 1998. Fungal isolations were made from beetles colonizing felled trees, beetles that emerged from felled trees, tissue of colonized trees, and tissue of uncolonized trees. Dryocoetes affaber (Mannerheim) and Polygraphus rufipennis (Kirby) accounted for over 90% of the insects...

The rates (k) of hydroxymethylation of phenol, resorcinol. phloroglucinol, and several methylphenols in diluted 10% dimethylformamide aqueous alkaline solution were calculated based on the consumption of phenols and formaldehyde. The k values of phloroglucinol and resorcinol relative to that of phenol were about 62000 and 1200 times, respectively. The phenols that have methyl or hydroxyl groups at the C-3 or C-5 position (or both) have larger rate constants than phenols with substituents at other positions. Several kinds of atomic charge of the carbons on the aromatic ring of phenols were...

Oudemansiella fibrillosa and Pouzarella caribaea are described as new from the Guilarte National Forest Preserve in Puerto Rico.

Recyclability of kraft paper and linerboard coated with commercial zein and paraffin wax or a zein-lipid mixture was evaluated using conventional recycling processes. Zein, an alcohol-soluble protein from corn, exhibits both grease and water vapor barrier properties. Strength properties, grease resistance, and water vapor barrier proper-ties were measured on handsheets prepared from fiberized coated and recycled kraft paper and linerboard. The coating reduced water vapor transmission rates (WVTR) and grease permeation 16% and 100%, respectively, on handsheets prepared from reslushed kraft...

The objective of this study was to determine if transverse vibration methods could be used to effectively assess the structural integrity of wood floors as component systems. A total of 10 wood floor systems, including 3 laboratory-built floor sections and 7 in-place floors in historic buildings, were tested. A forced vibration method was applied to the floor systems to determine the natural frequency and assess the stiffness and structural integrity. The results show that deterioration in wood floor systems can be identified by measuring damped natural frequency of those floors. The...

The U.S. economy entered a period of slow growth in 2000, tilting toward economic recession in 2001, the first broad economic downturn in a decade. This recent downturn was associated with a recession in U.S. industrial output from 2000 through 2001. U.S. paper and paperboard production declined from 1999 to 2001, with total production 8% lower in 2001 than the historical peak in 1999. The recession in manufacturing and downturn in paper and paperboard were linked to an exceptionally strong U.S. dollar, which attracted a flood of imported goods, limited growth in exports, and contributed...

Mountains and mountains of sawdust, hog fuel and wood chips have been generated by wood-processing mills and accumulated in large mountains in the past. But because of today's environmental con-straints, simply accumulating waste in piles is no longer acceptable. Landfilling may not be an option because of high tipping fees and the high costs of transportation to the landfill. Wood waste can be used as a biomass fuel to generate energy and produce alcohol as a by-product. For simple incineration, new technology smokeless burners can operate with very little amounts of smoke. The heat can...

The unique climates and industrial mix in southeast and south central Alaska are challenges being met by the region's organics recyclers. OMPOSTING wood residuals in Alaska has become increasingly important in recent years as wood processors and other industrial waste managers search for environmentally sound and profitable outlets. Traditionally, Alaska?s sawmills have had dependable markets?supplying area pulp mills with high quality chips. However, the recent closure of two major pulp facilities in southeast Alaska has greatly reduced demand for the region?s wood residuals. Further...