183 research outputs found
Method For Obtaining Wood/Bark Adhesion Measurements on Small Samples
Using the Instron Tester, a procedure has been developed for measuring wood/bark adhesion on small samples. Using very small, specially prepared samples, wood/bark adhesion measurements were made on twenty-four hardwoods and eighteen conifers. High dormant season wood/bark adhesion in hardwoods was found to be associated with the presence of fibers in the inner bark. The procedure appears to be useful in identifying difficult-to-debark species and evaluating methods of reducing adhesion
Morphological and Bark Strength Characteristics Important to Wood/Bark Adhesion in Hardwoods
Dormant season wood/bark adhesion was determined for twenty-four hardwood species using a previously described Instron testing machine method. Wood/bark adhesion was compared, using simple and multiple correlation techniques, with bark specific gravity, inner bark strength, bark toughness, wood specific gravity, wood toughness, percent bark fibers, and percent sclereids. Wood/bark adhesion was found to be positively correlated with percent bark fibers, bark toughness, and inner bark strength. Wood/bark adhesion was negatively correlated with percent sclereids in the bark. Morphologically, it appeared that the presence of fibers increased inner bark strength, sclereids decreased inner bark strength, and inner bark strength had a major influence on wood/bark adhesion. A multiple correlation comparison employing wood toughness and inner bark strength accounted for 69% of the wood/bark adhesion encountered
Coal Spoil-Bank Materials as a Medium for Plant Growth
The use of draglines and mechanical shovels to uncover and remove coal from surface mines has greatly increased in importance in the last 20 years. Strip mining, as this is called, has resulted in a greater per man day coal production and a greater percentage recovery of coal. Along with this increased production and increased efficiency in the use of one resource there occurs a change in the use capability of land mined for coal
Wood and Paper Properties of Vacuum Airlift Segregated Juvenile Poplar Whole-Tree Chips
Whole-tree chips from a hybrid poplar clone (Populus 'Tristis #1') grown under short rotation, intensive culture (SRIC) were separated into three fractions using vacuum airlift segregation (VAS). The fractions were: accepts, which was predominantly a woody fraction; rejects, which contained less wood and more bark and twigs; and fines, which consisted mostly of bark particles. The raw material quality was evaluated and kraft pulp and paper properties were determined on the whole-tree chips and each VAS fraction as well as on a 50:50 mixture of the accepts: rejects fractions. A 50:50 mixture of VAS accepts and 55-yr-old mill-run jack pine was also studied. Pulp and paper properties of the whole-tree chips, the VAS accepts and rejects, and a 50:50 mixture of accepts:rejects were similar and were only slightly lower in quality than those of mature aspen chips. The 50:50 mixture of VAS accepts and mill-run jack pine was acceptable by industrial standards. These results suggest that whole-tree chips from SRIC poplar stands can be mixed with conifer chips to supplement furnishes for kraft pulping
Crystallographic analyses of an active HIV-1 ribonuclease H domain show structural features that distinguish it from the inactive form
Bark and wood properties of pulpwood species as related to separation and segregation of chip/bark mixtures. Project 3212, report two : a progress report to members of Group Project 3212
"February 14, 1975.""Members of Project 3212: Abitibi Paper Company, Ltd., Blandin Paper Company, the Procter and Gamble Company, Scott Paper Company, Weyerhaeuser Company.""The Institute of Paper Chemistry, Marianne L. Harder, research assistant, John D. Hankey, research associate, Dean W. Einspahr, senior research associate, and John W. Swanson, director, Division of Natural Materials and Systems.
Wood/bark adhesion and methods of reducing adhesion in hardwood species. Project 2929, report one : a progress report to Members of Group Project 2929.
"December 21, 1970.""The Institute of Paper Chemistry ... Dean W. Einspahr, John D. Hankey, W. A. Wink, Miles K. Benson, and John W. Swanson.
Remote Sensing of Ploidy Level in Quaking Aspen (Populus Tremuloides Michx.)
Ploidy level in plants may influence ecological functioning, demography and response to climate change. However, measuring ploidy level typically requires intensive cell or molecular methods. We map ploidy level variation in quaking aspen, a dominant North American tree species that can be diploid or triploid and that grows in spatially extensive clones. We identify the predictors and spatial scale of ploidy level variation using a combination of genetic and ground‐based and airborne remote sensing methods. We show that ground‐based leaf spectra and airborne canopy spectra can both classify aspen by ploidy level with a precision‐recall harmonic mean of 0.75–0.95 and Cohen\u27s kappa of c. 0.6–0.9. Ground‐based bark spectra cannot classify ploidy level better than chance. We also found that diploids are more common on higher elevation and steeper sites in a network of forest plots in Colorado, and that ploidy level distribution varies at subkilometer spatial scales. Synthesis. Our proof‐of‐concept study shows that remote sensing of ploidy level could become feasible in this tree species. Mapping ploidy level across landscapes could provide insights into the genetic basis of species\u27 responses to climate change
The carbohydrate-binding specificity and molecular modelling of Canavalia maritima and Dioclea grandiflora lectins
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