The essential oil components of cedar heartwoods play an important role in the durability of these trees. Yet, the composition of these oils and identity of many of the compounds remains unknown, or incompletely know for some commercially important cedar heartwoods. The essential oil extracts of Alaska Yellow Cedar (Chamaecyparis...
This study identified new compounds with pest control activities. The two sources of candidates that were followed here were the main heartwood extract of Alaska Yellow Cedar (AYC) constituents and several semi-synthetic counterparts. Five compounds were isolated and identified for the first time in AYC heartwood in this research: two...
Heartwood can have properties that are distinct from sapwood,
including resistance to insect and microbial attack. Despite the practical
importance of heartwood formation in trees, a review of the literature revealed
that little was known about the effects of environmental factors on heartwood
quality or how variations in heartwood properties...
Synthetic adhesives, such as phenol-formaldehyde (PF) resins and urea-formaldehyde (UF) resins, have dominated the wood adhesive market since they were introduced in the wood products industry. Formaldehyde, as a key component in the manufacturing of PF and UF resins, has been classified as a known human carcinogen by the International...
In wood-plastic composites (WPCs) a compatibilizer is often used to improve
the interfacial adhesion between the hydrophilic wood filler and the hydrophobic
plastic matrix. At present, while the basic concepts of compatibilization are
understood, the optimized chemical structures of an effective compatibilizer, including
the ideal structures of the wood-binding domain...
Rubber without reinforcement has limited applications. The strength of reinforced rubber composites can be ten times stronger than that of unreinforced rubbers. Therefore, rubber composites are widely used in various applications ranging from automobile tires to seals, valves, and gaskets because of their excellent mechanical elastic properties. Silica and carbon...
Agroforestry is a traditional farming practice in American Samoa that has helped to sustain the livelihood of the native population for centuries. These once self-sufficient islands have become economically dependent on U.S monies and other external resources during the past century. Dependency has caused a shift in the carrying capacity...
Western redcedar (Thuja plicata Donn.) is a valuable commercial species found in
the northwestern United States and southwestern Canada. This dissertation includes four
papers focused on wood and stem characteristics of second-growth western redcedar, and
how those characteristics vary within the stem or how they are influenced by cultural
practices....
In undisturbed N-limited forested catchments, DON may represent over 90% of the total N lost in streams. Some ecologists have suggested that plant-derived reactive polyphenols may be responsible for DON binding and transport because polyphenol-protein complexes are known to precipitate out of solution, bind to mineral surfaces or organic matter...
Wood-plastic composites (WPCs) are one of the fastest-growing sectors of the
wood composites industry. However, the strengths of WPCs are typically low
because of the poor interfacial adhesion between hydrophilic wood and
hydrophobic thermoplastics. A compatibilizer that can form bridges between wood
and plastics is required to give WPCs desirable...
Natural fibers are gaining popularity as reinforcement materials for thermoset resins over the last two decades. Natural fibers are inexpensive, abundant, renewable and environmentally friendly. Kenaf fibers are one of the natural fibers that can potentially be used for reinforcing unsaturated polyester (UPE). As a polymer matrix, UPE enjoys a...
Patterning of metal oxides typically involves a multi step process, involving
depositing a resist, patterning that resist with some form of lithography, etching the
oxide through the resist, and finally removing. This process can be simplified if the
resist is removed and replaced with a metal oxide that can be...
Formaldehyde-based adhesives such as urea-formaldehyde (UF) and phenol-formaldehyde (PF) adhesives dominate the current wood adhesive market. However, these adhesives are derived from petrochemicals and carcinogenic formaldehyde. In this study, we developed two formaldehyde-free adhesives based on abundant, renewable, and inexpensive soy flour (SF).
The first adhesive was mainly composed of...
Large numbers of vintage reinforced concrete deck-girder bridges remain in the national bridge inventory. Many of these exhibit diagonal cracking and other distress. Due to the design practices of the time, it is common to observe cracks at locations where flexural reinforcing steel is terminated along the span. The presence...
Focus on Forestry is published by Oregon State University's College of Forestry. Our goal is to keep Forestry alumni, friends, faculty, staff, and students informed about the College of Forestry and its many activities and programs.
Microchannel devices are rapidly evolving process technology with a wide variety of applications. Microchannel devices hold the potential to transform many separation processes. One potential application for such microchannel devices is kidney dialysis. By reducing the size and cost of the device, this technology offers the potential to allow dialysis...
This study examined the relationship of interfacial shear strength (IFSS) and
bending strength (MOR) of several different wood-plastic composites (WPC's).
Plastics utilized were high-density polyethylene (HDPE) and polypropylene (PP).
Pine and oak were used as the wood species. Compatibilizers used included maleicanhydride
polyethylene (MAPE), polymeric methylene diphenyl diisocyanate (PMDI),
KymeneTM,...