bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of Photoprotection of Wood Coatings by Using Inorganic Nanoparticles as Ultraviolet Absorbers
Authors: Auclair Nicolas , Riedl Bernard , Blanchard Vincent , Blanchet Pierre
Published: October 2013

Ultraviolet (UV) light is high-energy radiation that induces degradation of organic compounds, such as wood. To prevent UV damage, several strategies have been used, including creating a UV light barrier at the wood surface. The most common strategy is to apply a coating to the wood surface. However, coating alone may not be effective enough to protect wood exposed outdoors. For example, clear coatings often contain additives to protect the material from UV radiation (hindered amine light stabilizers, quenchers, UV absorbers). This article reports work on the photostability of wood surfaces coated with waterborne nanocomposite urethane-acrylate systems in outdoor conditions. The wood color variation of sugar maple (Acer saccharum Marsh) was measured following accelerated aging. Different types of nanoparticles (ZnO, CuO) were used in water in predispersed and powder forms. Once cured, the nanoparticle dispersions were characterized by transmission electron microscopy. The best photoprotection was obtained with ZnO predispersed in water. Our major conclusion is that ZnO nanoparticles are better than CuO nanoparticles as additives intended to reduce the discoloration of clear-coated wood exposed outdoors. The highest increase in gloss was achieved with the mixture of inorganic and organic UV absorbers, which appear to show synergistic behavior.
Effect of Initial Preservative Treatment on Electrical Conductivity in Douglas-Fir Pole Sections
Authors: Morrell Jeffrey J. , Clauson Milo , Love Connie S.
Published: October 2013

The effect of copper naphthenate treatment on electrical resistance of Douglas-fir utility poles was compared with similar poles either left untreated or treated with pentachlorophenol (penta). Penta-treated and untreated wood had similar electrical resistance shortly after treatment and after a 3-month outdoor weathering period. Electrical resistance of copper naphthenate–treated wood was more variable but consistently greater, indicating that poles treated with this chemical would not pose an increased risk to utility personnel working on them.
Effect of Hemicellulose Extraction on Physical and Mechanical Properties and Mold Susceptibility of Flakeboard
Authors: Hosseinaei Omid , Wang Siqun , Rials Timothy G. , Xing Cheng , Taylor Adam M. , Kelley Stephen S.
Published: October 2013

Hemicellulose is the most hydrophilic polymer of wood, and as a polysaccharide, it has potential applications in conversion to biofuels. The objective of this study was to enhance properties of flakeboard by extracting hemicellulose. Hot-water pretreatment was performed to extract hemicellulose under different temperatures (140°C, 155°C, and 170°C) and times (30 and 60 min). The flakes were blended with 5 percent liquid phenol-formaldehyde resin and 1 percent wax emulsion. The mat was pressed at 200°C for 5 minutes. The physical and mechanical properties and the susceptibility of flakeboard to mold were studied. Panels made from the hemicellulose-extracted flakes showed remarkable decreases in water absorption and thickness swelling without a decrease in mechanical properties. Resistance of the panels to the mold growth also increased with increasing mass loss due to extraction. The most severe condition of extraction (170°C, 60 min), in addition to having the lowest water absorption and thickness swelling, showed the highest mold resistance.
Evaluation of a Heat Treatment Schedule for the Asian Longhorned Beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae)
Authors: Myers Scott W. , Bailey Sian M.
Published: October 2013

The Asian longhorned beetle, Anoplophora glabripennis, is an invasive pest that poses a serious threat to many species of North American hardwoods. An efficacious heat treatment schedule for this insect is crucial to allow wood to move from quarantined areas in the United States. A series of experiments were conducted using naturally infested trees to evaluate the International Standards for Phytosanitary Measures Rule No. 15 heat treatment schedule (56°C core temperature for 30 min) on overwintering A. glabripennis larvae. Results indicate that this treatment is effective, as no overwintering larvae were observed to survive. Overwintering larval stage, heating rates, oven load factors, and treatments are reported.
Maritime Pine Stress-Laminated Timber Bridges: Losses of Prestress Forces and Flexural Behavior
Authors: Jorge L. , Lopes S. , Cruz H.
Published: October 2013

This article presents a study on stress-laminated timber bridges. The technique is useful for the rehabilitation and construction of bridges. It consists of a series of timber planks placed side by side and compressed transversely with high-strength steel prestressing bars. A prototype of this kind of structure was built in the Department of Civil Engineering at the University of Coimbra. The prototype, a stress-laminated timber bridge deck with butt joints, was 6 m long, 2.7 m wide, and 0.20 m thick. The experimental program was developed with two main objectives: to study the evolution of the prestress value applied to the structure and to observe the bridge structural behavior under the effect of loads simulating the action of a standard vehicle. Practical difficulties and/or limitations and potentialities of the system when maritime pine is used as the timber material are also discussed. This article reports the experimental program and the results, with emphasis on the tension losses in the prestressed steel bars.
Seasonal Impacts of Bark Loss on Simulated Payloads, Bark Delivery, and Transport Costs for Freshly Harvested Logs
Authors: Murphy Glen E. , Pilkerton Stephen J.
Published: October 2013

Quantification of seasonal bark loss for two Oregon commercial tree species, Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa), was conducted at monthly intervals beginning in late October to early November 2009 and finishing in August 2010. All assessments were carried out on harvesting operations that were using mechanized processor heads with chains over rubber feed wheels. A total of 450 stems were assessed.

There was a substantial (up to five times) increase in areal bark loss, expressed as a percentage of log surface area, during late spring and early summer compared with the loss in winter. Areal bark loss appeared to be species dependent, with Douglas-fir incurring more than twice as much bark loss as ponderosa pine.

Seasonal differences in postharvesting bark volume and weight were determined by accounting for bark thickness and bark density. In winter, bark could be expected to account for 3 to 4 percent more of a stem's weight than in late spring to early summer. There were considerable differences between species in the contribution of bark to total weight, but not in the percent drop in weight between seasons.

It is shown that the seasonal changes in bark loss could be expected to lead to changes in solid wood truck payloads, transport costs, bark, and available energy (from bark) delivered to mills.
Status of Michigan's Forest Products Industry in the Changing Market Environment
Authors: Shivan G.C. , Potter-Witter Karen
Published: October 2013

The forest products industry plays a large role in Michigan's economy. It is one of the largest manufacturing sectors in the state, employing more than 29,000 individuals with an annual payroll of $1.2 billion. However, due to extended economic downturns, the industry is currently facing an adverse business environment, threatening its performance and even the retention of existing mills in some cases. Given this situation, an emerging bioenergy market could provide new opportunities for the struggling industry and help regain its vitality. However, this is possible only if sufficient resources are made available for both the traditional forest products industry, as well as new bioenergy facilities. Failure to do so will weaken already vulnerable forest products sectors. This study uses a mail survey of Michigan's primary forest products industry to provide insight into the state's forest products sector, with the aim of helping stakeholders make informed decisions for promoting bioenergy facilities while strengthening the existing operations within the state. Our findings suggest that there is a positive attitude among Michigan primary mills toward the introduction of wood-energy facilities in their wood basket, and hence there is evidence for a conducive environment for promoting bioenergy. However, careful consideration must be given to existing resource conditions, industry infrastructure, and strategies for maintaining sustained wood availability for promoting bioenergy industry that complements, rather than competes against, the traditional forest products sector.
Drivers and Barriers for Implementing Advanced Manufacturing Technology in China's Furniture Industry: An Exploratory Study
Authors: Yu Na , Shen Liming , Lewark Siegfried
Published: October 2013

Results of this exploratory study provide insights into the implementation of advanced manufacturing technology (AMT) in China's furniture industry by using a multiple-case study approach. Qualitative interviews were conducted with upper managers and specialists in production and human resource management from four Chinese furniture firms that are viewed as pioneers in implementing computer-integrated manufacturing (CIM) in China's furniture industry. The findings show that key drivers for implementing AMT in the Chinese furniture firms are problems in production process, the need to reduce dependence on employees' work skills, and difficulties in recruitment arising from increased labor costs and a shortage of skilled workers. In addition, findings of the study reveal that the barriers to AMT implementation in Chinese furniture firms are not only from the technology side but also due to nontechnological aspects. These results could help decision makers in conducting process innovation with regard to both technological and nontechnological aspects, as well as in taking their interactions into account. Moreover, our findings may also help forest products industries in other emerging countries that are moving toward introducing new working systems.
Nanocrystalline Cellulose: Morphological, Physical, and Mechanical Properties
Authors: Landry Véronic , Alemdar Ayse , Blanchet Pierre
Published: October 2013

Morphological, physical, thermal, and mechanical properties of nanocrystalline cellulose (NCC) were determined. Moisture content as well as oil absorption were also studied. The NCC was obtained from sulfuric acid hydrolysis of wood pulp. Transmission electron microscopy showed that NCC has a diameter of 10 nm and a length of 150 nm. Fourier transform–Raman spectroscopy and x-ray diffraction experiments both showed that NCC has a very high degree of crystallinity. Using an Abbe refractometer, the average refractive index of the NCC in different solvents was determined to be 1.499. Hardness and elastic modulus of the homogeneous, translucent NCC films were determined by nanoindentation technique. Oil absorption and moisture content were related to the particle size.
Treatment of Fast-Growing Poplar with Monomers Using In Situ Polymerization. Part I: Dimensional Stability and Resistance to Biodegradation
Authors: He Wen , Nakao Tetsuya , Yoshinobu Masahiro , Zhang Qisheng
Published: October 2013

Fast-growing poplar (Populus ×euramericana NL-95) has been extensively cultivated in China. However, because of its poor quality, poplar wood is commonly used only in the manufacture of low-grade wood products. If the wood could be improved by postharvest treatment, it would be more useful and more saleable. Such modification is possible. Our team has developed a protocol to modify fast-growing poplar by impregnating poplar wood with styrene (ST) and glycidyl methacrylate (GMA); this treatment is followed by in situ polymerization by means of thermal treatment. Experimental results show that the treated wood absorbed only one-fifth of the water absorbed by untreated wood when both were submerged in water for 1 week. The treated wood was also two times as dimensionally stable. When treated and untreated wood specimens were exposed to termites and to the fungi that cause dry rot, the treated wood was 9.3 times as resistant to termites and 3.8 times as resistant to fungi. Specimens of treated wood were examined using Fourier transform infrared spectroscopy, which showed that a grafting reaction and copolymerization had occurred, bonding the hydroxyl groups of the wood cell walls to the GMA and ST. Scanning electron microscope observation of the treated wood showed that the cell lumens had been filled with polymers and that the interfaces between wood cell walls and polymer were hard to distinguish.
Treatment of Fast-Growing Poplar with Monomers Using In Situ Polymerization. Part II: Static and Dynamic Mechanical Properties; Thermal Stability
Authors: He Wen , Nakao Tetsuya , Yoshihara Hiroshi , Xue Jiang Shen
Published: October 2013

Part I of this article described the treatment of specimens of fast-growing poplar (Populus ×euramericana NL-95) with styrene (ST) and glycidyl methacrylate (GMA) monomers. It detailed the results of tests for water absorption, dimensional stability, and termite and fungus resistance. This part continues the previous work. It examines the static and dynamic mechanical properties, as well as the thermal stability, of polymer-infused wood (PIW). Static mechanical properties of PIWs were assessed in terms of bending strength, compressive strength, and Brinell hardness. Our results showed that, as a result of the treatment, these properties were significantly increased. Moreover, the PIW treated with GMA-ST showed greater mechanical strength than PIW treated with ST alone. We believe that this is due to the formation of cross-linked bonds between the GMA-ST and the hydroxyl groups of the wood's cell walls. Dynamic mechanical analysis (DMA) demonstrated that, at normal temperatures, storage modulus E′ and molecular structure stability of wood were significantly enhanced by the treatment. However the loss factor (tan δ) of PIWs was sharply elevated at a higher temperature range. Finally, thermogravimetric analysis (TGA) indicated that the thermal stability of wood was greatly improved by the treatment; the wood treated with GMA-ST showed slightly higher thermal stability than the wood treated with ST alone.
Predicting Wood Quality of Green Logs by Resonance Vibration and Stress Wave in Plantation-Grown Populus ×euramericana
Authors: Yin Yafang , Jiang Xiaomei , Wang Lijuan , Bian Mingming
Published: October 2013

A cost-effective estimation of wood quality of hardwood green logs is needed. The purposes of this study were to investigate and compare two nondestructive acoustic methods to predict the wood quality of green logs from a poplar I-72 (Populus ×euramericana cv. I-72/58 “San Martino”) plantation. After log measurements, small clear wood specimens were cut and air dried to 12 percent moisture content. The static bending modulus of elasticity (MOE) of small clear wood specimens was about 15 and 20 percent greater than the dynamic MOE of green logs based on resonance vibration (Efr) and stress wave (Esw). However, good correlations (R) between Efr and Esw of logs and bending MOE of 0.806 and 0.848 (P <0.001), respectively, were observed. Significant correlations were also found between the Efr and Esw of logs and the modulus of rupture and compressive strength parallel to grain (σc) of small clear wood specimens (P < 0.001). The results indicate that both acoustic techniques were effective predictors of wood quality, although the stress wave method was found to be more accurate and reliable than the resonance vibration method. The longitudinal changes of strength properties with tree height could be tracked by these two methods.
Fuel Characterization of Pellet Chips
Authors: Eriksson Gunnar Lars , Boman Christoffer , Bergsten Urban , Bergström Dan
Published: October 2013

Small hardwood chips, known as pellet chips, were characterized and combusted in two different pellet burners, installed in a residential boiler specially designed for pellet combustion. The average particle mass was about 10 percent of the mass of an 8-mm pellet, with a similar surface-to-volume ratio. The bulk density of pellet chips was 160 to 170 kg m−3 at 10 percent moisture content (about 25% to 35% of 8-mm pellet bulk densities). The combustion performance was good, with average O2 and CO values (by volume) at 17.6 percent (SD, 0.6%) and 200 ppm (SD, 210 ppm), respectively, for the bottom-fed burner and 14.2 percent (SD, 1.1%) and 330 ppm (SD, 93 ppm), respectively, for the top-fed burner. Thus the study indicates that pellet chips produced with commercially available equipment can be used in ordinary pellet combustors, provided that the fuel feeding rates are increased and the moisture content well below 20 percent. More accurate market assessments will require the investigation of the performance of different types of combustion equipment with fuels of different qualities.
Ultimate Failure Load and Stiffness of Screw Jointed Furniture Cabinets Constructed of Particleboard and Medium-Density Fiberboard
Authors: Kasal Ali , Yuksel Mehmet , Fathollahzadeh Ali , Erdil Yusuf Ziya , Yildirim Nadir
Published: October 2013

The objective of this study was to investigate the effects of material type, screw diameter, and screw length on ultimate failure load and stiffness of four-sided furniture cabinets. In total, 81 four-sided test cabinets were constructed in 1/1 dimensions. Assembly of cabinets was done using nine different sizes of screws ranging from 3.5 by 40 mm to 5 by 50 mm. Panel materials were 18-mm-thick particleboard (PB) and 16- and 18-mm-thick medium-density fiberboard (MDF1, MDF2). Cabinets were anchored at two points located underneath the top panel and tested under static load. Loading procedures of the American National Standards Institute/Kitchen Cabinet Manufacturers Association were followed during the static tests. Test results showed that 18- and 16-mm MDF cabinets yielded higher failure loads and stiffness values compared with the 18-mm PB cabinets. Test results also indicated that increasing either screw diameter or screw length tended to have a positive effect on the failure load and stiffness values. The strongest and most rigid four-sided cabinets were obtained with 4-mm-diameter and 50-mm-long screws if the construction panel material was 18-mm-thick MDF, 5-mm-diameter and 45-mm-long screws if the construction panel material was 16-mm-thick MDF, and 5-mm-diameter and 50-mm-long screws if the construction panel material was 18-mm-thick PB.
Information Technology Adoption in US and Canadian Forest Products Industries
Authors: Hewitt Richard , Sowlati Taraneh , Paradi Joseph C.
Published: October 2013

Information technology (IT) has advanced at a rapid rate during the past three decades, and when used well, IT can bestow a competitive advantage in the modern economy. This article reviews key studies on IT adoption in US and Canadian forest products industries, summarizes their common findings, gives insights on these commonalities, and recommends future areas of research. The most frequent conclusion of these studies was that most forest products firms used only basic ITs. IT adoption rates were often found to be positively correlated with firm size and proportion of sales from exports. Most firms invested less than $10,000 in IT, which was not enough to develop sophisticated IT. Firms often perceived the largest benefits of IT to be promotional in nature, while cost-cutting operational benefits were usually ignored. Overall, with the exception of the pulp and paper industry, a cautious attitude toward IT adoption was observed. The low IT adoption by this sector could be attributed to several factors, such as being a highly production-oriented industry with few IT savvy personnel.
Mold Growth on Sapwood Boards Exposed Outdoors: The Impact of Wood Drying
Authors: Sehlstedt-Persson Margot , Karlsson Olov , Wamming Thomas , Morèn Tom
Published: October 2013

Mold growth on dried Norway spruce and Scots pine sapwood boards was investigated in an accelerated outdoor field test for 96 days. The boards were dried using three different methods of stacking: single stacking, double stacking with the sapwood sides in each pair facing toward each other, and double stacking with sapwood sides facing outward. Drying was performed at three temperatures: 25°C, corresponding to air drying, and kiln drying at 70°C and 110°C. The degree of mold growth was visually assessed on both sides of each board. On average, pine boards showed a higher level of mold growth than the spruce boards. The highest average level of mold growth was found on the boards kiln dried at 70°C, whereas the air-dried boards and the boards kiln dried at 110°C showed considerably less mold growth. Stacking the boards during drying had a large impact on mold susceptibility of the sapwood. This study confirmed that, during the drying process, it is possible to direct the migration of nutrients in sapwood toward one chosen side of each board by double stacking; the opposite side leaches out, which has a great impact on surface mold growth. Chemical analyses of monosaccharide sugar gradients beneath the boards' surfaces confirmed the results.
EPD - Environmental Product Declarations for Wood Products—An Application of Life Cycle Information about Forest Products
Authors: Bergman Richard , Taylor Adam
Published: October 2013

Transparent and credible environmental labeling of products is vital for a sustainable future. Ecolabeling shows information on the environmental performance of products, processes, and services. This article focuses on one type of ecolabeling referred to as environmental product declarations (EPDs) that provide environmental impact information based on life cycle assessment (LCA) data. Businesses and consumers who are not familiar with life cycle analysis can use LCA-based EPDs for comparison between competing products, much like using nutritional labels. In addition, this article describes the process of developing EPDs from LCA data in conjunction with product category rules and the status and future needs of EPDs in the U.S. forest products industry.
Log Sawing Practices and Lumber Recovery of Small Hardwood Sawmills in West Virginia
Authors: Lin Wenshu , Wang Jingxin , Wu Jinzhuo , DeVallance David
Published: October 2013

A total of 230 logs from two species, red oak (Quercus rubra) and yellow poplar (Liriodendron tulipifera), were measured in five typical hardwood sawmills across West Virginia to evaluate log sawing practices and lumber recovery. Log characteristics such as length, diameter, sweep, taper, and ellipticality were measured in sawmills, while log scale and grade were determined by using the US Department of Agriculture Forest Service grading rules. The characteristics of sawing equipment, such as headrig type, headrig kerf width, and sawing thickness variation, were recorded during the measurement process. A general linear model was used to statistically analyze the relationship between lumber recovery and characteristics of logs and sawing practices. Results indicated that factors such as log grade, log diameter, species, log sweep, log length, and some two-factor interactions significantly affected lumber value and volume recovery.
Withdrawal Capacity of Joints Constructed with 9.5-mm and 15.9-mm Through-Bolts and Diameter Nominal 15-mm and 25-mm Pipe-Nut Connectors
Authors: Eckelman Carl A. , Haviarova Eva
Published: October 2013

Tests were conducted to determine the withdrawal capacities of 10-mm (nominal ⅜-in.) and 15.9-mm (nominal ⅝-in.) through-bolts with Diameter Nominal (DN) 15-mm (nominal ½-in.) and DN 25-mm (nominal 1-in.) pipe-nut connectors intended for use in light-timber frame construction. The capacity of unreinforced 15.9-mm through-bolts with DN 25-mm pipe-nut connectors was approximately 31.1 kN; the capacity of comparable reinforced connectors was approximately 71.2 kN. Likewise, the withdrawal capacity of smaller unreinforced 10-mm through-bolts with DN 15-mm pipe-nut connectors was approximately 13.3 kN; comparable reinforced connectors had a capacity of 17.8 kN. Similar 10-mm through-bolts with DN 10-mm pipe couplings had a capacity of 26.7 kN. Overall, results indicate that high-capacity joints can be constructed with through-bolt and pipe-nut connectors.
Shading Aboveground L-Joint and Lap-Joint Tests: Comparison of White Pine and Sugar Maple Test Assemblies
Authors: Clausen Carol A. , Lindner Daniel L.
Published: October 2013

Five-year performance ratings are presented for two types of untreated, uncoated wood joints (L and lap) in aboveground tests under shaded conditions. The effect of shading on moisture entrapment in pine and maple L and lap joints was evaluated in a moderate decay zone (Madison, Wisconsin). Variations were observed between wood species, visual ratings, joint type, moisture content readings, and fungal growth on the specimens. Representative fungal fruiting bodies were identified as members of the Peniophorella praetermissa species complex by microscopic and DNA analyses. After 5 years, the highest average rating (indicative of most severe deterioration) occurred in white pine L-joint specimens followed by maple lap joints and maple L joints. Pine and maple L-joint specimens demonstrated considerably lower rating variation between specimens compared with lap-joint specimens. White pine lap joints shaded with a tarp had lower average moisture content but showed similar average ratings to pine lap joints shaded by a tree. Regardless of the shading method, white pine lap joints had the lowest average decay rating. Under shaded conditions in a moderate decay zone, untreated and uncoated L-joint performance was notably more uniform from specimen to specimen than lap-joint performance following 5 years of outdoor exposure. A single-point moisture content taken at the time of inspection was not a reliable indicator of the degree or rate of decay for aboveground joint test assemblies evaluated in this study. Likewise, uniform specimen wetting or drying is not predictable under shaded conditions.
Preservative Leaching from Copper Azole–Treated Lumber: A Comparison between the Full-Cell Method and the Passive-Impregnation Method
Authors: Ando Keisuke , Islam Md Nazrul , Yamauchi Hidefumi , Hattori Nobuaki
Published: October 2013

This study investigated the leaching of copper azole (CA-B) preservative, according to JIS K 1571 standard, from sundri (Heritiera fomes Buch.-Ham.) lumber treated by full-cell and passive-impregnation methods. Although the preservative retention was similar for both methods, penetration was higher with the passive-impregnation method (66%) than with the full-cell method (43%). Further, it was found that the leaching of preservative was significantly higher in wood treated by the full-cell method (1.18%) than by the passive-impregnation method (0.92%).
Can Timber Hedge against Inflation? An Analysis of Timber Prices in the US South
Authors: Zhang Mingshu , Mei Bin , Harris Thomas G. , Siry Jacek P. , Clutter Michael L. , Baldwin Sara S.
Published: October 2013

The US South is one of the world's leading timber producing regions. This article analyzes stumpage prices, the price a landowner receives for standing timber product, without the influence of growth or consideration of land price. Under the framework of Fisher's hypothesis and the real capital asset pricing model, we investigated stumpage prices' ability to hedge against inflation in 12 US southern timber regions using Timber Mart-South data. Prices for five major timber products, including pine sawtimber, hardwood sawtimber, pine pulpwood, hardwood pulpwood, and pine chip-n-saw, for each individual timber region and all regions combined were analyzed in a system by rolling regression and weighted least squares. Using instantaneous quarterly returns, no uniform conclusion could be drawn for either individual regions or the timber portfolio—the inflation hedging ability varied greatly by product and by time. Using 40-quarter average returns on the timber portfolio instead, it was found that pine pulpwood and chip-n-saw could hedge against both expected and unexpected inflation. Hence, stumpage prices alone should not be viewed as consistent or persistent hedges against inflation unless they are held for a long period.
Evaluation of the Energy Balance for the Production of Briquettes from Biomass
Authors: Arrieche Rafael , Saloni Daniel , van Dyk Herman , Lemaster Richard L.
Published: October 2013

Wood densification consists of processing wood by-products such as sawdust and chips into uniformly sized particles that are compressed into wood-based fuel products (pellets and briquettes). The main advantages are related to handling improvements of residual wood and energy generation opportunities when compared with wood chips from other forms of wood residues. The objective of this study was to evaluate the energy balance for production of briquettes from wood residues.

This research involved determining the energy consumption required to perform the main manufacturing operations to produce wood briquettes: size reduction, drying, and densification of wood. The amount of energy that can be obtained from the combustion of wood briquettes was also measured. The effects of several factors such as wood species, material dimensions, and raw material moisture content on the energy requirements for manufacturing briquettes were studied.

Four densification strategies were evaluated from an energy consumption standpoint: single size reduction (shredding) of dry lumber and wood chip densification; single size reduction (shredding) of wet lumber, drying, and wood chip densification; double size reduction (shredding and hammermilling) of dry lumber and wood particle densification; and primary size reduction (shredding) of wet lumber, wood chip drying, secondary size reduction of wood chips, and wood particle densification. At most 8 percent of total energy available from combustion of briquettes is required to produce briquettes. Moreover, drying wet wood residues consumes about 80 percent of the energy used in producing the briquettes.

This study shows that manufacturing briquettes from wood residues is feasible from an energy consumption perspective.
Effect of Fractionated Palm Fruit Shell Bio-Oil on Seed Germination
Authors: Sunarta Sigit , Uehara Tohru , Katoh Sadanobu
Published: October 2013

Palm fruit shell was pyrolyzed in a closed simple reactor. The physical and chemical properties of the pyrolytic oil (bio-oil) were characterized. The effect of original and fractionated bio-oil was analyzed as a germination promoting agent. Raw palm shell bio-oil character differed from that of wood and other biomass. The pyrolysis temperature caused differences in yield and acetic acid content, but there were no significant differences in specific gravity, pH, or the major chemical components of shell bio-oil. The effect of shell bio-oil on germination and radicle growth of seeds depended on pyrolysis temperature, fraction, and dilution rate. Original shell bio-oil had the best effect on germination and radicle growth. Dilutions of 102 and 103 inhibited germination and radicle growth for three kinds of seeds.
Field Tests of Naturally Durable Species
Authors: Morris Paul Ian , Ingram Janet , Larkin Glenn , Laks Peter
Published: October 2013

Six wood species generally accepted to represent a range of natural durability were exposed in American Wood Protection Association (AWPA) E7-09 (ground-contact) and AWPA E25-08 (aboveground) decay tests at field sites located near Maple Ridge, British Columbia, and Petawawa, Ontario, in Canada and Gainesville, Florida, and Hilo, Hawaii, in the United States. Variables examined included comparisons of sapwood to heartwood, old growth to second growth, and effect of a protective coating. The tests began between October 2004 and February 2005. Results are reported after 5 years of exposure. Ground-contact decay rates were fastest at sites in Florida and Hawaii. Yellow cedar (Callitropsis nootkatensis (D. Don) Örsted), western red cedar (Thuja plicata Donn ex D. Don), and eastern white cedar (Thuja occidentalis L.) had the highest condition ratings (least decay) for this measure after 5 years of exposure, followed by western larch (Larix occidentalis Nutt.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and then tamarack (Larix laricina (Du Roi) K. Koch). The aboveground decay rate was highest in Hawaii. For this measure, yellow cedar and western red cedar again had the highest average decay ratings (least decay) after 5 years of field exposure, followed by Douglas-fir, western larch, and tamarack. Eastern white cedar did not fit neatly into this pattern. It was durable at three of the four sites but failed rapidly in Hawaii. Sapwood appeared to have a larger impact on aboveground decay than on ground-contact decay. No substantial difference was found between old-growth and second-growth decay rates.
Control of Black Stain Fungi with Biocides in Semitransparent Wood Coatings
Authors: Stirling Rod , Uzunovic Adnan , Morris Paul I.
Published: October 2013

One of the frequent signs of early failure in semitransparent wood coatings is colonization by “black stain” fungi, such as Aureobasidium pullulans. A laboratory method evaluating the ability of various wood coating formulations to inhibit the growth of black stain fungi on artificially weathered, coated wood in petri dishes was developed. Meaningful results were obtained after only 6 weeks of incubation. Selected biocides and biocide combinations formulated in a semitransparent coating including selected combinations of diiodomethyl-p-tolylsulfone, 3-iodo-2-propynyl butylcarbamate (IPBC), propiconazole, tebuconazole, thiabendazole, fludioxonil, chlorothalonil, oxine copper, copper metal, and naphthoquinone were evaluated. Combinations of propiconazole with IPBC and propiconazole with IPBC and thiabendazole were most effective in this test. Further work is needed to evaluate the use of other coatings and test fungi with the laboratory test method and to evaluate the performance of the best-performing biocides in field exposures.
Effects of Pyrolysis Conditions on Yield of Bio-Chars from Pine Chips
Authors: Yan Qiangu , Toghiani Hossein , Yu Fei , Cai Zhiyong , Zhang Jilei
Published: October 2013

The influences of temperature, heating rate, purge gas type, and flow rate on the yield of chars produced from pyrolyzing southern pine chips were investigated. Pyrolysis temperatures were between 450°C and 1,000°C, with heating rates of 0.5°C/min, 1.0°C/min, 10°C/min, 30°C/min, 50°C/min, and 100° C/min. Purge gases, nitrogen (N2), hydrogen (H2), and N2–H2 mixture (10% H2), were used at flow rates from 100 to 1,000 mL/min. Pine char yield decreased as temperature, heating rate, or purge gas flow rate increased. Two regions with significantly different decrease rates of pine char yield can be identified for temperature or heating rate as they increase. The yield decrease rate turning points were 550°C and 10°C/min for yield-temperature and yield-heating rate charts, respectively. The pine char yield was lowest when hydrogen was the purge gas and highest with nitrogen.
Improving the Sanding Process of Black Spruce Wood for Surface Quality and Water-Based Coating Adhesion
Authors: Cool Julie , Hernández Roger E.
Published: October 2013

The sanding of black spruce wood prior to coating application was optimized for feed speed and grit size. As feed speed increased, the surface roughness and the surface energy of the samples increased. For the different sanding programs, reductions of the surface roughness and the contact angles were observed with a finer grit abrasive. The initial pull-off strength was statistically similar regardless of the feed speed and grit size. However, both the feed speed and the grit size affected coating adhesion following the accelerated weathering treatment. Because there was no correlation between the surface quality parameters and the pull-off strength, the latter had to be measured to determine coating performance on black spruce wood. In the present work, a two-stage sanding program combined with a feed speed of 17 m/min resulted in good surface quality and pull-off strength.
Preliminary Experiments on the Manufacture of Hollow Core Composite Panels
Authors: Sam-Brew Solace , Semple Kate , Smith Gregory D.
Published: October 2013

Structural honeycomb panels consist of a lightweight, often paper, honeycomb column core between two thin, stiff face sheets, which results in a very light structure with high strength and stiffness. These panels have long been used in the shipping and aerospace industries and for furniture components in Europe. The wider adoption of honeycomb panels by Canadian furniture manufacturers is hampered by a lack of experience and technical data on their manufacture, properties, and performance. This study attempts to address this missing information with a series of experiments to test the influence of Kraft paper honeycomb type, orientation, cell wall height, and face sheet type on sandwich strength properties (flexural, shear rigidity, and panel deflection).

Failure of sandwich panels occurs by buckling of the honeycomb cell walls under the load point; panel load-bearing capacity is significantly improved by the use of stiff face sheets such as plywood. The strongest and stiffest panels are made with small honeycomb cells (16 mm). The extra cost and bulk associated with using paper-laminated pre-expanded honeycomb is not matched by increased bending strength and is therefore unnecessary. Bending strength is significantly enhanced by aligning the honeycomb so that the nodes and ribbon direction are perpendicular to the long axis (loading direction) of the panel due to the ability of the core to flex and conform to the curvature of the face sheets under load. The results from this study offer insights that furniture manufacturers may use to fabricate and potentially improve the properties of honeycomb sandwich panels.
Antifungal Activity of Organic Extracts from Juniperus virginiana Heartwood against Wood Decay Fungi
Authors: Mun Sung Phil , Prewitt Lynn
Published: October 2013

Easter red cedar (Juniperus virginiana) is a valuable source of heartwood extractives that provide decay resistance against termites and wood decay fungi. This study sought to determine the antifungal activity of heartwood extracts obtained using solvents with increasing polarity (hexane, chloroform, ethyl acetate, and methanol) against two wood decay fungi. The heartwood was extracted with methanol, and the methanol extract was sequentially extracted with hexane, chloroform, and ethyl acetate. The yield of the methanol extractives was 5.26 percent based on dry wood and the percentages of the hexane, chloroform, and ethyl acetate soluble fractions from the methanol extract were 46.4, 8.3, and 28.7 percent, respectively. Hexane and chloroform soluble fractions showed a high inhibitory effect on the growth of the wood decay fungi Trametes versicolor and Gloeophyllum trabeum. Gas chromatography–mass spectrometry analysis identified skeletons of sesquiterpenes and sesquiterpene alcohols in both extracts and the most abundant compounds identified, cedrol, cedrenes, and thujopsenes, were individually screened for antifungal activity. Among the three major sesquiterpenes, cedrol and thujopsene showed the highest inhibitory effects against G. trabeum and T. versicolor, respectively.
Supplemental Treatments for Timber Bridge Components
Authors: Barnes H. M. , Amburgey T. L. , Sanders M. G. , Lindsey G. B.
Published: October 2013

A series of joint treatments on southern pine, red oak, and yellow-poplar were evaluated. These included treatments applied in holes that were subsequently capped, treatments applied to bolt holes and/or bolts, treatments applied to felt pads located between wooden members, and treatments applied directly to the surfaces of the joints. Water-soluble diffusible systems applied in holes adjacent to joints generally performed more poorly than expected because of the lack of rainfall during the exposure period. The notable exception was a copper-borate paste applied directly to the joint area. Application of a solvent-borne copper naphthenate with or without a water repellent to felt pads was also very effective. Water repellent alone and fumigant treatments gave unsatisfactory performance over the long term.

To simulate hazards encountered by piling, kiln-dried untreated southern pine pole stubs that received various supplemental treatments were placed in the field for 41 months. Upon groundline evaluation of these test specimens, it was noted that seven preservatives or combinations of preservatives looked very favorable. The following treatments yielded sound stubs with no evidence of decay or insect attack: (1) copper-borate paste applied to the surface at and below groundline; (2) copper-borate paste applied to the surface at and below groundline plus boron rods inserted into holes near groundline; (3) copper-borate paste applied to the surface at and below groundline plus fumigant inserted into holes near groundline; (4) pentachlorophenol grease applied to the surface at and below groundline; (5) fluoride paste applied to the surface at and below groundline; (6) fluoride paste applied to the surface at and below groundline plus boron rods inserted into holes near groundline; and (7) fluoride paste applied to the surface at and below groundline plus fumigant inserted into holes near groundline.
An Examination of Michigan's Logging Sector in the Emerging Bioenergy Market
Authors: G.C. Shivan , Potter-Witter Karen
Published: October 2013

Logging firms, as suppliers of raw material, form an important part of Michigan's forest products industry. Given the increasing interest in wood-based bioenergy production, their role has become increasingly important. For this study, we used a mail survey of Michigan's logging firms to provide an outlook of the logging sector within the state. The aim was to understand the status of existing logging businesses and to explore their potential role in the woody biomass supply chain. Our findings reveal that the state's logging firms have been facing difficulty in retaining their business and in running operations profitably in recent years. Mill closures in the past decade have had significant negative impacts on half of the responding firms. Given this situation, the introduction of wood-to-energy facilities could provide new market opportunities for logging firms in the state. Loggers in general were found to be supportive of introducing such facilities in their wood basket. Availability of timber to meet the feedstock demands of new and existing facilities could, however, become a challenging issue in the future. Insufficient timber sales and high stumpage prices were identified as the major barriers to increased harvesting by the logging firms in our survey. On average, the responding firms reported that in the majority (83%) of their logging jobs, they leave logging residues on site, suggesting that there is little or no market for such materials at present. This could change, however, with market development and improvement in the logging and transportation facilities in the future.
Effects of Pressing Temperature and Particle Size on Bark Board Properties Made from Beetle-Infested Lodgepole Pine (Pinus contorta) Barks
Authors: Gupta Gireesh , Yan Ning , Feng Martin W.
Published: October 2013

Mountain pine beetle (Dendroctonus ponderosae)–infested lodgepole pine (Pinus contorta) bark was used to make particleboard panels (bark board) without synthetic resins. The effects of pressing temperature and particle size on the mechanical properties of the bark boards were examined. The study revealed that pressing temperature and particle size have great influence on mechanical, physical, and hygroscopic properties of self-bonded bark boards. Higher pressing temperatures resulted in improvements in all properties studied, including increases of modulus of elasticity and modulus of rupture by approximately 4 times and an increase of internal bond strength by nearly 10 times when comparing boards pressed at 170°C versus 230°C. Boards produced from fine bark particles showed better mechanical performance than boards produced from coarser bark particles except for internal bond strength, which was highest in boards containing bark particles of mixed sizes. Scanning electron microscopic images of fractured surfaces of bark boards derived from different particle sizes and pressed at different temperatures indicated that fine and mixed particles and higher pressing temperatures led to denser packing.
Commercialization Potential of Viscoelastic Thermal Compressed Wood: Insights from the US Forest Products Industry
Authors: Macias Natalie , Knowles Chris , Kamke Fred , Kutnar Andreja
Published: October 2013

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 the viscoelastic thermal compression (VTC) process, which can dramatically increase the strength and stiffness of any wood species.

To advance VTC wood from the concept evaluation stage to the development stage, concept testing interviews were conducted with individuals in the forest products industry. Opinions, ideas, and insights were gathered from interviewees concerning potential applications for VTC wood, as well as advantages and barriers to commercialization.

As a whole, interviewees thought the most viable uses for VTC wood were laminated veneer lumber, plywood, concrete forms, transportation components, and flooring. The most frequently mentioned advantages to commercialization included increased mechanical properties and the utilization of a low-value wood species; barriers to commercialization were cost and the forest products industry's resistance to change. Overall, interviewees thought VTC wood would be successful as long as it was not markedly more expensive than similar products.
Recycling of Pentachlorophenol-Treated Southern Pine Utility Poles. Part II: Mechanical and Delamination Properties of Laminated Beams
Authors: Piao Cheng , Monlezun Charles J. , Gibson Mark D. , Groom Leslie H.
Published: October 2013

Reusing decommissioned utility poles and other preservative-treated wood reduces the total amount of preservatives in the environment and the need to fall the trees in the forest, offering economic and ecological advantages. In a previous study, the pentachlorophenol (penta) retention and mechanical properties of decommissioned penta-treated southern pine utility poles and pole sections were investigated. The current study evaluated the mechanical and delamination properties of laminated beams made of penta-treated utility pole wood. A total of 45 laminated beams and 15 solid-sawn beams were fabricated from decommissioned penta-treated utility pole wood and untreated southern pine virgin wood. Three composition schemes and two surface preparation methods were investigated for their effects on penta retention, bending, glue-line shear, and delamination properties of the laminated beams. Penta-treated utility pole wood absorbed more penta than virgin wood during retreatment. The bending strength of the laminated beams met American National Standard Institute Standard 05.3. However, percent delamination of the laminated beams failed to meet the standard requirement set by ASTM Standard D2559, and thus, penta-treated utility pole wood beams consolidated by resorcinol phenol formaldehyde resin cannot be used in exterior exposure conditions.