Treesearch

Raman spectroscopy is being increasingly used to carry out in situ analysis of wood and other lignocellulosics. To obtain useful information from the spectra, the vibrational bands need to be assigned in terms of contributions from various chemical components and component sub-structures. In additional, so that the technique can be better applied as an analytical tool, an understanding of chemical treatment induced spectral changes is important. In the present work, Raman spectra of four MWLs (black spruce, loblolly pine, aspen, and sweet gum) were compared and, for black spruce MWL,...

It is hard to imagine a world without forests. Forests provide a wide range of benefits at the local, national, and global levels. Some of these benefits depend on leaving the forest alone or subjecting it to only minimal interference. Other benefits can only be realized by harvesting the forest for wood and other products. The shrinking land base and growing human population have heightened the challenge for forestry and forest products utilization to produce the needed types and quantity of trees. The concept of sustainability is central to sound forest management and the subject of much...

When silviculture researchers in central Europe were gathering together to form IUFRO in 1892, forest products researchers were occupied with making useful forest products and conserving the forest resource through wise use. Forest products researchers did not become an active part of IUFRO until 50 years later. Research in forest products was stimulated by World War I and II1wood was essential for airplanes, ships, packaging, construction, and derived products. As World War II drew to a close, the newly established United Nations provided a forum for bringing together efforts that would...

This report describes how lumber can be air-dried most effectively under outdoor conditions and illustrates the principles and procedures of air-drying lumber that were developed through field investigations and observations of industrial practices. Particular emphasis is placed on the yarding of lumber in unit packages. Included are topics such as why lumber is dried, advantages and limitations of the drying process, properties of wood in relation to drying, layout of the drying yard, piling methods, causes and remedies of air-drying defects, and protection of air-dried lumber.

Many specialty treatments can be applied to wood to either improve its performance or change its properties. Treatments addressed in this chapter are those that make permanent changes in the shape of a wood product, improvements in dimensional stability, or improvements in performance through combinations with nonwood resources.

Chemical pulping of kenaf fiber is comparatively new. In this study, bast, core, and whole stalk kenaf fibers were pulped using a soda-AQ pulping process and various pulping conditions. Handsheets were evaluated for density, Canadian standard freeness, brightness, opacity, smoothness, and tensile, burst, and tear indexes and strength. The results indicate that commercially viable pulp can be produced from kenaf using 12% NaOH, 0.15 AQ, and 2 h of cooking at 160*C.

The physical properties of kenaf offer potential as an alternative raw material for the manufacture of paper. Investigations to date have not determined whether core and fiber should be pulped together or separately. Kenaf bast and core fibers of different cultivars were pulped under various kraft pulping conditions and physical properties: density, Canadian Standard freeness, caliper, elongation, tensile strength, tensile index, tensile energy absorption, ISO brightness, printing opacity, bursting strength, burst index, tear resistance, tearing index, and smoothness of the test sheets...

Mildew growth is an ongoing problem. Fungal spores land on surface and, under the environmental conditions, grow. Ideal conditions are warm, moist climates, oxygen, and a substrate that serves as a nutrient source for mildew. Mildew growth on finishes cause discoloration and premature failure of the finish. Prevention of mildew can be done by pretreating the wood with a preservative that contains a mildewcide. Removal of mildew is achieved by using appropriate cleaning solutions. Finishes that contain synthetic mildewcides, with or without zinc oxide, help the finish resist mildew growth.

More than 160 million tons of waste wood were generated last year. This report from the Forest Products Laboratory analyzes recovery data and methods.

As in other industries, the fortunes of the U.S. pulp and paper industry are now closely tied to the global economy. The U.S. pulp and paper sector exhibits fairly steady production and growth trends, but its economic fortunes have become intertwined with the bglobal cyclec of supply and demand. Exposure to the global cycle has increased for the U.S. in recent decades with increased levels of U.S. product exports. One effect of this exposure in recent years is increased market volatility associated with trade-related adjustments in export demands and capacity utilization. Price volatility...