Treesearch

This review summarizes patents related to paper recycling that first appeared in patent databases during the 2004. Two on-line databases, Claims/U.S. Patents Abstracts and Derwent World Patents Index, were searched for this review. This feature is intended to inform readers about recent developments in equipment design, chemicals, and process technologies for recycling paper and alternative products derived from post-consumer paper. Only briefsummaries of individual inventions are included in this review. Because many of the patents are not readily available in English, much of the...

As the problems associated with sustaining and enhancing the world's forest and agricultural resources compete with the needs of a rapidly increasing and affluent population, the management of our land becomes a much more complex and important issue. One of the most important environmental features of wood and other woody-like fibers is that they are renewable and can be sustainably managed. Composite wood and natural biofiber products are beneficial to humans and to the environment in that they serve as environmentally effective alternatives to other non- enewable and/or non- or less-recyc...

At present, there is no regulatory or policy guidance at the Federal level that permits, prohibits, or qualifies practice for salvaging and reusing building materials coated with lead-based paint (LBP). This paper describes the current regulations and standards relative to LBP in buildings (in particular LBP on lumber and timber products), LBP mitigation, and disposal of LBP-containing waste, and the applicability of these regulations and standards to recovering and reusing building materials.

Low-rise nonresidential building construction is an important market for lumber, structural wood panels, nonstructural wood panels, and engineered wood products in the United States. This report examines low-rise nonresidential buildings of four or fewer stories only, because buildings with five or more stories are normally severely restricted by building code from being wood framed. In 2003, 1,324 million board feet of lumber, 56 million bf of glulam timber, 2,293 million square feet, 3/8-in. basis, of structural panels, 76 million square feet, 3/8-in. basis of nonstructural panels, 49...

Creosote has a long history of successful use as a wood preservative, but polycyclic aromatic hydrocarbons in this preservative have raised environmental concerns, particularly when creosote-treated wood is used in aquatic environments. A number of models have been developed to predict the risk of creosote use in aquatic environments, but one limitation of these models is a lack of data on the initial rates of creosote migration from treated wood. In this study, the effect of flow rates on creosote migration from freshly treated wood immersed in fresh water were examined. Seven of 16...

Here we explore the significance of fungal diversity on ecosystem processes by testing whether microfungal ‘preferences’ for (i.e., host recurrence) different tropical leaf species increases the rate of decomposition. We used pairwise combinations of [gamma]-irradiated litter of five tree species with cultures of two dominant microfungi derived from each plant in a microcosm experiment. The experiment was designed to test whether early leaf decomposition rates differed depending on relationships between the leaf litter from which the fungi were derived (i.e., the source plant) and the leaf...

This report provides general and statistical information on forest products markets in terms of production, trade, consumption, and prices. The current state of the United States economy is described. Market developments are described for sawn softwood, sawn hardwood, softwood log trade, wood-based panels, paper and paperboard, fuelwood, and forest products prices. Policy initiatives that can impact domestic markets and international trade in wood products are also discussed in some detail. Projections for the year 2005 are also presented.

A high quality draft genome sequence has been generated for the lignocellulose-degrading basidiomycete Phanerochaete chrysosporium (Martinez et al. 2004). Analysis of the genome in the context of previously established genetics and physiology is presented. Transposable elements and their potential relationship to genes involved in lignin degradation are systematically outlined. Our current understanding of extracellular oxidative and hydrolytic systems is described. Areas of uncertainty are highlighted and future prospects discussed in light of the newly available genome data.

The mineral scale that deposits in digesters and bleach plants is formed by a chemical precipitation process. As such, it is accurately described or modeled using the solubility product equilibrium constant. Although solubility product identifies the primary conditions that need to be met for a scale problem to exist, the acid base equilibria of the scaling anions often control where in the process scale will occur and are the primary control method to minimize or prevent scale in a bleach plant. As equilibrium processes, both the acid/base equilibrium and solubility product are influenced...

Dynamics of single curved fiber sedimentation under the gravity are simulated by using lattice Boltzmann method. The results of migration and rotation of the curved fiber at different Reynolds numbers are reported. The results show that the rotation and migration processes are sensitive to the curvature of the fiber.