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Treated timber bridges have been widely used for railroad and highway bridges throughout the United States during the 20th century. However, improvements in preservative technology are needed as a result of changing environmental views and public perceptions concerning the use of preservative treated wood in aquatic environments. Within the past 15 years, three national programs have been established to advance technologies related to timber transportation structures. A key design aspect for timber highway bridges is the selection of preservative treatment to improve durability while...

Five new species of Psilocybe from the Caribbean are described: P. caribaea, P. egonii, P. subpsilocybioides, P. zapotecoantillarum and P. zapotecocaribaea. All except P. zapotecocaribaea, which is known only from Martinique, are native to Puerto Rico. Psilocybe guilartensis, previously described from Puerto Rico, is the most commonly collected species of Psilocybe in Puerto Rico. New information on morphology is provided for P. guilartensis, and an emendation of the species circumscription is presented.

The IPCC Guidelines (IPCC 1997) provide an outline of how harvested wood could be treated in national greenhouse gas (GHG) inventories. This section shows the relation of that outline to the approaches and estimation methods to be presented in this Appendix. Wood and paper products are referred to as harvested wood products (HWP). It does not include carbon in harvested trees that are left at harvest sites.

Approximately 720 sawmills produce most of the softwood lumber in the U.S. The largest 200 of these, ranked mostly according to 2002 production, are displayed in the table on the ensuing pages. Where the actual production statistic was not released, it was estimated by subtracting from capacity any lost volume due to downtime. In a few instances where neither production nor indications of downtime were available, capacity was used to compile the listing. This year the Hampton mill in Willamina, Ore. came out on top. According to a company source the 385MMBF output would have been even...

Commercial wood flour, the most common wood-derived filler for thermoplastics, is produced in a mixture of particle sizes and generally has a lower aspect ratio than wood and other natural fibers. To understand how wood flour and fiber characteristics influence the mechanical properties of polypropylene composites, we first investigated the effect of different sizes of wood flour particles on the mechanical properties of wood-flour-filled polypropylene composites. We then compared the properties of wood-flour-filled composites to those of composites reinforced with refined wood fiber. We...

Sol-gel surface deposition of a hydrophobic polysiloxane coating on wood was accomplished by using a mixture of a low molecular weight multifunctional alkoxysilane, methyltrimethoxysilane (MTMOS), and a high molecular weight multifunctional alkoxysilane, hexadecyltrimethoxysilane (HDTMOS). Investigation of the surface chemistry and morphology of the wood specimens by means of ATR-FTIR, energy-dispersive X-ray analysis, X- ray photoelectron spectroscopy, SEM, and atomic force microscopy indicated that the sol-gel process results in deposition of polysiloxane networks that are bonded to the...

A number of naphthalimide (NI) derivatives are used as efficient laser dyes, in medicine or in transmission electron microscopy. Only N,N- naphthaloylhydroxylamine (NHA) has been shown to be an effective wood preservative against wood decay fungi and termite damage. However, limited information is available concerning the analytical detection of Nl-derivatives in treated timber. There is a clear need for the analytical characterisation; e.g. with regard to the penetration depth or the assessment of retention after leaching. This paper describes the development of a gas chromatographic...

With the objective of using FT-Raman to quantitatively analyze ethylenic units in lignin in thermomechanical pulps (TMPs), coniferyl alcohol, coniferin, coniferaldehyde, and G-DHP lignin models were used to first demonstrate that the technique was fully capable of quantifying ring conjugated ethylenic units. Based on this result, the amount of ethylenic units in TMP was determined by quantifying the unit-specific contribution to the Raman spectra. The findings were that, in fully bleached spruce TMP (brightness 79.9%), the concentration of coniferyl alcohol ethylenic units was 1.38% and in...

The Raman microprobe technique was applied to structural analysis of single ramie fibers during mercerization. Polarized laser beam was irradiated on a ramie fiber in 0-30 % NaOD/D2O with the electric vector at 0 or 90° to the fiber axis, and Raman spectra thus obtained were studied in relation to the concentration of NaOD in D2O. Conversion of -OH to -OD in ramie cellulose with NaOD/D2O proceeded with an increase in the concentration of NaOD, and almost all OH groups in ramie cellulose were converted to -OD by the treatment with NaOD/D2O of more than 15 %; almost all intra- and inter-molec...

The lack of industrially suitable microorganisms for converting biomass into fuel ethanol has traditionally been cited as a major technical roadblock to developing a bioethanol industry. In the last two decades, numerous microorganisms have been engineered to selectively produce ethanol. Lignocellulosic biomass contains complex carbohydrates that necessitate utilizing microorganisms capable of fermenting sugars not fermentable by brewers' yeast. The most significant of these is xylose. The greatest successes have been in the engineering of Gram-negative bacteria: Escherichia coli, Klebsiell...