Treesearch

Chemical modification of wood can improve its dimensional stability and resistance to biological degradation and moisture, but modification can also create a new surface for bonding. Acetylation of wood results in the loss of hydroxyl groups, making the wood more hydrophobic and reduces its ability to hydrogen-bond with the adhesive. In contrast, reacting wood with butylene oxide or propylene oxide lowers swelling of wood in water but does not reduce the number of free hydroxyl groups. The hydrogen bonding model of adhesion would favor the oxide-modified wood over the acetylated wood for...

In recent years, several fiber new fiber length analyzers have been developed and brought to market. The new instruments provide faster measurements and the capability of both laboratory and on-line analysis. Do the various fiber analyzers provide the same length, coarseness, width, and fines measurements for a given fiber sample? This paper provides a comparison of fiber length analyzers over a range of fiber types. Integrated Paper Services, Inc., the USDA FS Forest Products Laboratory, and the Paper Science Department at UW-Stevens Point evaluated six distinct pulp samples using the...

In this chapter, we examine the use of classical methods to study fungal diversity. Classical methods rely on the direct observation of fungi, rather than sampling fungal DNA. We summarize a wide variety of classical methods, including direct sampling of fungal fruiting bodies, incubation of substrata in moist chambers, culturing of endophytes, and particle plating. We also cite and discuss study designs for documenting diversity and monitoring species, and analytical methods that have been used for data produced using classical methods. Selected examples of such mycological studies are...

Our forests are a naturally renewable resource that has been used as a principal source of bio-energy and building materials for centuries. The rapid growth of world population has now resulted in substantial increases in demand and in consumption of all raw materials. This now provides a unique opportunity of developing new bio-based composites. The 100-year history of the softwood plywood industry provides a good example of a successful development of an idea, a process, and eventually marketable product. The key to developing a marketable bio-based composite for use as a building...

Characteristics of microwave drying of wood strands with different initial moisture contents and geometries were investigated using a commercial small microwave oven under different power inputs. Temperature and moisture changes along with the drying efficiency were examined at different drying scenarios. Extractives were analyzed using gas chromatography=mass spectrometry (GC=MS). The results showed that the microwave drying process consisted of three distinct periods (warm-up period, evaporation period, and heating-up period) during which the temperature, moisture change, and drying...

Although preservative treatments prolong the life of wood, they can also contribute to the corrosion of fasteners. The corrosion of fasteners merits further study because it can affect the long-term durability of structures and fundamental knowledge of corrosion in wood is limited. The goal of this study is to determine the viability of electrochemical impedance spectroscopy (EIS) as an accelerated testing procedure for determining the corrosion rate of metals in water-saturated wood.

Data files for U.S., Canada manufactured home builder practice tabulations.

“Wood Fueled Boiler Financial Feasibility” is a spreadsheet program designed for easy use on a personal computer. This program provides a starting point for interested parties to perform financial feasibility analysis of a steam boiler system for space heating or process heat. By allowing users to input the conditions applicable to their current or proposed fuel systems, “Wood Fueled Boiler Financial Feasibility” provides an opportunity to compare wood or bark fuel as alternates to the existing fuel. This program has been designed for use by most decision-makers seeking basic insight such...

Bond formation primarily involves adhesive rheology and interface chemistry. Bonded assembly strength, however, primarily involves the viscoelastic dissipation of stress over the entire assembly. Models can aid in the understanding of where and why failure occurs and how to improve the strength of the assembly. Horioka and Marra have both proposed models which define failure zones for wood bonds. Although mechanical property changes from the bulk adhesive to the bulk wood are more of a continuum than the discrete domains used in these models, the location and cause of failure are easier to...

This paper reviews demand and supply trends for hardwood fiber in the United States. The objective is to illustrate nationwide shifts in demand and supply and show how the hardwood pulpwood market reacts to those shifts at a regional level. Thus, the market situation is illustrated using an economic rationale, and trends are projected under assumptions about future shifts in demand and supply. Results indicate the market is recovering from a major structural shift in demand, a downturn over the past decade driven by economic globalization, and also by increased paper recycling since the...