Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Pressed and dried plant specimens are useful as teaching aids and reference sources for plant identification, or as decorative material. Select plants to be mounted with care, prepare properly, and accompany by adequate, clearly expressed, written identification data. This publication suggests materials and methods for selecting and preparing plants for...
Pressed and dried plant specimens are useful as teaching aids and reference sources for plant identification, or as decorative material. Select plants to be mounted with care, prepare properly, and accompany by adequate, clearly expressed, written identification data. This publication suggests materials and methods for selecting and preparing plants for...
Lithia-silica compositions between lithium disilicate and pure
silica were explored theoretically and experimentally, with special
emphasis on structural miscibility. Diffusion couples of vitreous
materials were prepared and annealed. Best success in preparation
was achieved by using electron-bombardment heating in vacuum to
melt the less refractory glass and let it solidify...
Published April 1941. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Hygro-mechanical effect is a general term applied to all phenomena that involves interaction between moisture content and mechanical characteristics of hygroscopic materials by analogy to thermo-mechanical effects. The hygromechanical effects include (but are not limited to) free shrinkage/swelling, effect of moisture on elastic modulus, strength, creep, failure mechanisms, and mechano...
Purpose of the Study: The purpose of this investigation was to measure some of the effects of an elementary science program, the Science Curriculum Improvement Study (SCIS) on science achievement of certain sixth grade students. Important to the problem was how the SCIS students compared with students exposed to a...
This analysis of Colombia's System of National Park Reservations
accomplishes four objectives: 1) The historical development of national
parks in Colombia was described; 2) The status, as of August,
1974, of the areas administered by the Colombian Renewable Natural
Resources Development Institute (INDERENA) was summarized; 3) An
analysis of major...
The engineering design process and the advancement of future computer-aided-design systems need new design aids to be used during the conceptual design phase. This design phase is where information gathering and understanding of the problem are developed, analyzed and broken into small more manageable elements. These elements consist of customer...
The Oregon Forestry Fact Sheets are designed for the leader as tools to support the group experience. Leaders are encouraged to make copies for their members.
On the Oregon coast, however, the issue of water supply has become paramount, especially given the need to restore instream flows in order to restore coastal salmon runs and meet water quality standards. With the ebb and flow of population and the economic growth of Oregon coastal communities, three hypotheses...
This study examined the experience of three secondary
science student teachers from Western Oregon State College
in Monmouth, Oregon during the Spring quarter of 1990. The
question was: What is student teaching like from the point
of view of the student teacher?
The research methodology was qualitative, more
specifically participant...
Fundraising in the 21st century is becoming an increasingly important component of rural community colleges' (RCCs) overall funding strategies. Alumni represent a significant population of potential college supporters. The problem facing rural community colleges involves fiscal viability through developing innovative fundraising practices and identifying emerging sources of additional revenue. The...
This work focuses primarily the development of methods for imaging microbial biofilms in opaque porous media using x-ray computed microtomography (CT). Two methods for evaluating biofilms in porous media are presented. The first focuses on the addition of silver-coated, hollow glass microspheres to a biofilm-containing micro-model. The silver-coated microspheres affix...
Species are one of the foundational units upon which entire fields of scientific inquiry are built. Discovering and documenting the planet’s biodiversity remains one of the grand challenges of science. A proper conceptualization of species provides a critical framework for diverse fields such as biophysics, biochemistry, agriculture and pharmacology, and...
Restoration programs effectively prevent or mitigate wildfires and pest outbreaks in the forest lands. The most common approach is to selectively harvest smaller and dead trees in order to preserve larger and superior trees. Ponderosa pine, Pinus ponderosa, (PP) lumber is one of the common species harvested from restoration programs...
This study examined the decay resistance of the pine and maple components of wood plastic composites (WPC' s) of varying thicknesses exposed on several culture media to wood decay fungi under laboratory conditions. The ability of malt agar extract (MEA), potato dextrose agar (PDA), amended basal salts, sawdust (maple and...
Summarizes information on wood as an engineering material.
Presents properties of wood and wood-based products
of particular concern to the architect and engineer. Includes
discussion of designing with wood and wood-based products
along with some pertinent uses.
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...
Correction: 7 Mar 2016: The PLOS ONE Staff (2016) Correction: Successful Recovery of Nuclear Protein-Coding Genes from Small Insects in Museums Using Illumina Sequencing. PLOS ONE 11(3): e0151124. https://doi.org/10.1371/journal.pone.0151124
The effects of incorporation of selected biocides on physical and mechanical properties of aspen strandboard were assessed using five copper-based preservatives or zinc borate at three retention levels. Tebuconazole or 4,5-dichloro-2-N-octyl-4-isothiazolin-3-one (DCOI) were added as co-biocides to selective copper-based treatments. Mold box tests showed that only panels treated with DCOI...
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...
The sweet potato is one of the world’s most widely consumed crops, yet its evolutionary history is poorly understood. In this paper, we present a comprehensive phylogenetic study of all species closely related to the sweet potato and address several questions pertaining to the sweet potato that remained unanswered. Our...
Formaldehyde-based adhesives such as urea-formaldehyde (UF), phenol-formaldehyde (PF) are widely applied in wood-based composite industry. However, these adhesives are all petrochemical-based and could not sustain in a long term due to a limited reserve of oil and natural gas. Moreover, these adhesives emit carcinogenic formaldehyde in the production or use...
Bench scale column studies were used to examine the partitioning of microorganisms between groundwater
and a geologic medium and to examine the effect of hydrogeology (i.e., porous- versus fracture-flow) on
organism partitioning. Replicated columns were constructed with intact basalt core segments that contained
natural fractures and with the same basalt...
With the resurgence in the interest of using natural textile dyes, a solution must be found that will overcome the limitations of traditional natural dyes. This solution must also be safer for both humankind and the environment than are synthetic dyes. This study compares the colorfastness of commercially available synthetic...
Moisture durability is essential for wood composites, especially those used in building construction, where products are prone to weathering. The primary focus of this research was to determine if adhesive penetration into the cell wall has a positive influence on adhesive bond durability. To fully understand the measureable effects of...
The objective of this research project was to increase the density, strength, and stiffness of two low to medium-density diffuse-porous hardwood species. Wood used in this study was processed using a method of wood densification known as “Viscoelastic Thermal Compression” (VTC). The VTC process is a three phase treatment which...
Torsion test was evaluated as a method to determine the shear strength
parallel to grain of full-size structural composite lumber (SCL). Experimental
results of eighty-five rectangular (44 x 140 mm²) specimens were verified by finite
element analysis. Laminated strand lumber (LSL), laminated veneer lumber
(LVL) and parallel strand lumber (PSL)...
The purpose of this report is to make the existence of the Oregon
State College xylarium and this particular collection known to interested
individuals and agencies in the United States and Canada. At
the time of writing, the collection embraces 707 samples of 181
species representing 72 genera and 31...
The mechanical performance of wood-based composites is determined by the mechanical properties of their individual components and the effective load transfer between these components. In laminated wood composites, this load transfer is facilitated by the adhesive bond. The experimental methodology developed in this study measures and analyzes the full-field deformation...
Using plant fibers as a potential renewable material to substitute for glass fibers in fiber-reinforced polymer composites has been growing since the late 1990s. Due to high demand, there has been a shift towards ‘green concept’ material in many applications. Numerous secondary plant fibers have been explored as a source...
The objective of this project was to evaluate methods to remediate a wood I-joist with a single, circular hole in the web while leaving utilities in place. The methods were experimentally evaluated with a full-scale bending test using four equally spaced point loads. There were three depths of joists with...
Many nondestructive techniques for structural health monitoring are subjective and based on visual observations of degradation. In addition, dynamic properties of structures are already used to obtain quantitative structural health data. However, most current data collection is limited to localized damage on the structure, rather than global response. Recent research...
Variability in wood properties causes boards within a stack of lumber to
dry at different rates and reach different moisture content levels after drying is
completed. The consequence is that the boards will have properties that differ from
ones that were intended to be achieved by the drying process.
The...
The increasing demand for forest products and restricted use of natural forests has resulted in a shortage of high-strength wood fiber. The area covered by plantation forests is steadily rising, but the fiber produced by these forests is often unsuitable for high-strength applications. One attempt to combat this problem is...
Presently, the production of wood composites relies on the formaldehyde-based wood adhesives such as phenol-formaldehyde (PF) and urea-formaldehyde (UF). However, their dependence on exhaustible fossil fuels and the emission of carcinogenic formaldehyde prompt to develop an environmentally friendly adhesive from renewable natural resources. This work focuses on development and characterization...
Spraying of liquid adhesive onto wood surfaces has shown to be a highly effective and efficient method of application across many different wood-based composite industries. However, the dynamics of spraying are extremely variable and distribution can be affected by liquid properties (rheology, molecular weight distribution, and temperature), application parameters (disk...
The fabrication of nano-scale devices is a challenging, but potentially important, technology that has drawn a great deal of interest among researchers. Such nanoscale constructions utilizing a bottom-up approach for device building have many foreseeable applications in areas as diverse as miniaturized electronics, sensors, and biomedical devices.
One of the...
Rapid discoloration and checking of wooden surfaces when exposed outdoors has caused wood to fall out of favor as an outdoor building material, especially in applications where appearance is important. The surface appearance of wood products exposed outdoors can be improved through the application of film forming coatings or by...
The internal structure of natural fiber composites can be manipulated by controlling the spatial distribution of fiber orientation and internal chemical and thermodynamic conditions during their consolidation. Objects highly tailored to specific service demands may thereby be produced. Techniques to form miniature structural beams from oriented hemp and random wood...
Untreated wood is inherently hygroscopic and moisture content variations can have substantial effects on dimensional stability leading to the development of deep surface checks that further enhance moisture uptake and ultimately encourage deterioration. The horizontal exposure of wood crossties makes water repellency and dimensional stability particularly important in railroad applications....
The engineering community is increasingly moving towards the design of seismic force-resisting systems that limit post-earthquake damage and reduce downtime to increase urban resiliency. For example, structural spines can be used to provide an elastic load path to impose a more uniform drift distribution with building height, thereby reducing the...
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Table 20. Specimens used for BRB modeling calibration and BRB-MPP spine
specimen
The Pacific Coast variety of Douglas-fir was investigated.
The samples were tested using both forced and free vibrations. Transverse
vibrations were introduced by excitations on the side of the
samples. Forced vibrations were applied from 5000 to 0 hertz by a
vibration generator, and free vibrations were initiated by a...
Selective laser melting (SLM) is an additive manufacturing (AM) process that uses a laser beam to melt metal powder as it is spread onto the build surface using a roller or scraper, followed by rapid solidification to manufacture a 3D component, one layer at a time.
In SLM process, density...
Microscale X-ray computed tomography (XCT) is discussed as a technique for identifying 3D adhesive distribution in wood-adhesive bondlines. Visualization and material segmentation of the adhesives from the surrounding cellular structures require sufficient gray-scale contrast in the reconstructed XCT data. Commercial wood-adhesive polymers have similar chemical characteristics and density to wood...
Existing pressure sensitive adhesives (PSAs) are mostly based on petrochemicals. In this study, a novel PSA based on a renewable material, methyl oleate, was prepared and characterized. Methyl oleate was first epoxidized to form epoxidized methyl oleate that was subsequently hydrolyzed and acidified to form epoxidized oleic acid (EOA) which...
The merits of the photoelastic coating technique as applied to
wood were evaluated. Comparative tests were made on 12 nominal
two-by-four Douglas Fir boards. The object of these tests was to
determine the limitations of this technique, such as accuracy and
complexity of experimental procedure. Correlation of the experimental
results...
The objectives of this study were to 1) develop a relatively quick staining procedure that would detect incipient decay by color differentiation under fluorescence, 2) quantitatively assess the amount of decay present with the use of an image analyzer, and 3) re/ate loss in strength at various decay levels to...
Wood plays a key role in modern electrical infrastructure; crossarms and power poles utilize the high strength to weight ratio, availability and low cost of wood to facilitate the access of power to millions of Americans. However, wood presents a variety of challenges as a material. In structural applications, one...
There is no doubt that adhesive penetration plays an important role in wood bondline joint performance and durability; yet, to date there is no direct experimental evidence linking penetration depth with bond performance. This is, in part, because adhesive penetration is commonly assessed with various 2D microscopy techniques that are...
Full Text:
compared and optimized for the highest absorption contrast
in these wood-bondline specimens. However
Wood-based composites such as plywood and particleboard are produced with a thermoset adhesive via a hot-press process. At present, UF is the most commonly used thermoset adhesive for production of decorative plywood. The emission of the carcinogenic formaldehyde from UF-bonded panels during the use of panels affects the indoor air...
Friction dampers have been used successfully to dissipate seismic
energy in steel and concrete structures. The application is new to timber
structures. The objectives of this research were to design a slotted bolted
connection (SBC) and evaluate its potential as a passive energy damper in
timber brace.
The research was...
Raw material costs and limited material availability and quality have created
significant interest in and opportunities for the application of nondestructive
evaluation techniques to improve wood processing technologies. The incentives come
from the desire to 1) manufacture the highest valued product, 2) conserve the
amount of raw material used, 3)...
Carbon fiber reinforced polymer (CFRP) materials are emerging as an effective means of strengthening and rehabilitating bridges. Near surface mounting (NSM) is a newer technique for application of CFRP for retrofitting of bridge members that provides advantages over conventional strengthening techniques. The technique is still new and uncertainties remain regarding...
Quantitative and qualitative information on the retention of chlorinated residues in chloropicrin treated wood is lacking. Retention of chloropicrin and its chemical breakdown products in wood, and the effects of chloropicrin treatment of wood on invading decay fungi are explored in this thesis. Chlorinated residues in amounts up to 1.5%...
Anthropogenic modification watersheds and climate change have altered export from fluvial systems causing changes to the carbonate chemistry of river-influenced near shore environments. To determine the possible effects of riverine discharges on the mussel Perumytilus purpuratus, we performed in situ transplant experiments between river-influenced and open coastal habitats with contrasting...
ABSTRACT
Improved Fumigants
Chioropicrin, Vorlex and Vapam continue to control internal decay of
pressure-treated Douglas-fir poles 12 years after application. Fungitoxic quantities
of chloropicrin are present in the wood as high as 2.4 m (8 feet) above
the groundline. Solid methylisothiocyanate (MIT), which goes directly to a vapor,
is somewhat...
Evaluations of previously established field trials indicate that
chioropicrin, and Vorlex continue to provide protection to Douglas-fir poles,
although the degree of protection is diminishing. Reapplication of Vapam 18
years after the initial application eliminated fungi which had recolonized the
poles. Methylisothiocyanate (MITC) continues to protect Douglas-fir poles 12
years...