Research findings from faculty and students in Wood Science and Engineering http://hdl.handle.net/1957/4573 2013-05-25T10:10:44Z 2013-05-25T10:10:44Z Schauwecker, Christoph F. McDonald, Armando G. Morrell, Jeff J. http://hdl.handle.net/1957/38295 2013-04-23T15:36:15Z 2013-02-01T00:00:00Z

Performance of wood treated with prospective organic surface protectants upon outdoor exposure: FTIR spectroscopic analysis of weathered surfaces Schauwecker, Christoph F.; McDonald, Armando G.; Morrell, Jeff J. Visual appeal of wood is as important as its structural integrity in outdoor applications. Discoloration and checking of wood favor the utilization of alternative materials for outdoor cladding and decking. Lignin depolymerization is one of the critical processes leading to weathering. In the present paper, the potential of different classes of surface protection agents has been assessed on loblolly pine ( Pinus taeda ) impregnated with water repellents, organic UV inhibitors, and an organic biocide. The treated samples were exposed to predetermined doses of solar radiation in Eastern Oregon, and the chemical changes occurring on the surfaces were evaluated by FTIR spectroscopy. After 1-year exposure, lignin loss was complete on all surfaces; however, some treatments provided longer term protection than others. Organic UV light inhibitors were most effective in this regard. A petroleumbased water repellent with a melting point of 54 – 58 ° C also provided protection against lignin degradation. This is the publisher’s final pdf. The published article is copyrighted by De Gruyter and can be found at: http://www.degruyter.com/.

2013-02-01T00:00:00Z Reed, Daniel Bergman, Richard Kim, Jae-Woo Taylor, Adam Harper, David Jones, David Knowles, Chris Puettmann, Maureen E. http://hdl.handle.net/1957/36841 2013-02-13T21:02:24Z 2012-01-01T00:00:00Z

Cradle-to-Gate Life-Cycle Inventory and Impact Assessment of Wood Fuel Pellet Manufacturing from Hardwood Flooring Residues in the Southeastern United States Reed, Daniel; Bergman, Richard; Kim, Jae-Woo; Taylor, Adam; Harper, David; Jones, David; Knowles, Chris; Puettmann, Maureen E. In this article, we present cradle-to-gate life-cycle inventory (LCI) data for wood fuel pellets manufactured in the Southeast United States. We surveyed commercial pellet manufacturers in 2010, collecting annual production data for 2009. Weighted-average inputs to, and emissions from, the pelletization process were determined. The pellet making unit process was combined with existing LCI data from hardwood flooring residues production, and a life-cycle impact assessment was conducted using the Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts (TRACI) model. The potential bioenergy and embodied nonrenewable energy in 907 kg (1 ton, the functional unit of this study) of wood fuel pellets was also calculated. The pelletization of wood requires significant amounts of electrical energy (145 kWh/Mg), but the net bioenergy balance is positive. Wood pellets require 5.8 GJ of fossil energy to produce 17.3 GJ of bioenergy (a net balance of 10.4 GJ/Mg). However, if environmental burdens are allocated to the pellet raw material (flooring residues) by value, then the embodied fossil energy is reduced to 2.3 GJ. The pelletization unit process data collected here could be used in an assessment of the environmental impacts of pellet fuel, or when pellets are a pretreatment step in wood-based biorefinery processes. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Forest Products Society and can be found at: http://www.forestprod.org/.

2012-01-01T00:00:00Z Voelker, Steven L. Noirot-Cosson, Paul-Emile Stambaugh, Michael C. McMurry, Erin R. Meinzer, Frederick C. Lachenbruch, Barbara Guyette, Richard P. http://hdl.handle.net/1957/36612 2013-02-06T21:13:54Z 2012-05-01T00:00:00Z

Spring temperature responses of oaks are synchronous with North Atlantic conditions during the last deglaciation Voelker, Steven L.; Noirot-Cosson, Paul-Emile; Stambaugh, Michael C.; McMurry, Erin R.; Meinzer, Frederick C.; Lachenbruch, Barbara; Guyette, Richard P. Paleoclimate proxies based on the measurement of xylem cell anatomy have rarely been developed across the temperature range of a species or applied to wood predating the most recent millennium. Here we describe wood anatomy-based proxies for spring temperatures in central North America from modern bur oaks (Quercus macrocarpa Michx.). The strong coherence of temperature signals across the species range supports the use of these proxies across thousands of years of climatic change. We also used 79 subfossil oak log cross sections from northern Missouri, ¹⁴C-dated to 9.9-13.63 ka (ka is 1000 cal yr BP), to assess the frequency of oak deposition into alluvial sediments and a subset of these oaks for a wood anatomy-based reconstruction of spring paleotemperatures. Temperatures during the Younger Dryas cold period (YD) were up to 3.5 degrees C lower than modern temperatures for that region, equivalent to or lower than those experienced at the northern edge of the modern species range. Compared to extant oaks growing at much higher [CO₂], subfossil oaks had greater vessel frequencies. Besides very low theoretical (or estimated) xylem conductivity near the beginning of the oak record near 13.6 ka, vessel frequencies greater than modern trees compensated for reduced vessel dimensions so that theoretical xylem conductivity was consistently above that of modern trees at the cold northern sites. Significant correlations were found between the frequency of ¹⁴C-dated oaks and either delta δ¹⁸O from the NGRIP (North Greenland Ice Core Project) ice core or from the Cariaco grayscale marine-sediment record from the southern Caribbean sea. Oak deposition into alluvial sediments during the YD was significantly lower than expected given the average sample depth of oaks from 9.9 to 13.6 ka. Reduced oak deposition during the YD suggests that an abrupt shift in climate reduced oak populations across the region and/or changed the rates of channel movement across drainages. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esa.org/.

2012-05-01T00:00:00Z Burnard, Michael D. http://hdl.handle.net/1957/36505 2013-01-31T00:12:45Z 2012-10-23T00:00:00Z

Key factors influencing checking in maple veneered decorative hardwood plywood Burnard, Michael D. Face checking in decorative maple veneered plywood panels is a significant problem for hardwood plywood manufacturers, furniture makers, cabinetmakers, and consumers. Efforts made by panel producers and researchers to minimize checking conducted to-­‐date have been limited, and produced contradictory results. In this study the impact of four manufacturing factors believed to contribute to check development in decorative maple veneer panels were determined. The factors investigated were face veneer thickness and preparation, lathe-­‐check orientation, adhesive and core type. An efficient, automated, optical technique based on digital image correlation principles was developed and used to detect and measure checks as they develop. The novel new method for characterizing check severity and development was effective in efficiently measuring checking for a substantial number of samples. The results of the factor screening analysis reveal intricate four way interactions between factor levels contribute to check development, and that some combinations are likely to exhibit much more checking than others. Graduation date: 2013

2012-10-23T00:00:00Z