Historians and sociologists of science often identify the efflorescence of social stud ies of science with the work of postwar American intellectuals such as Robert K. Merton and Thomas S. Kuhn. They often also refer to the views of Michael Polanyi (1891-1976) on the roles of tacit knowledge, apprenticeship, social...
In this study, triglycidylamine (TGA) was synthesized and evaluated as a crosslinking agent for soy flour (SF) for making five-ply plywood from yellow poplar. Glycerol polyglycidyl ether (GPE) and trimethylolpropane triglycidyl ether (TTE) were also investigated as crosslinking agents for SF as adhesive for plywood. The plywood panels bonded with...
The most active phenolics in Quercus sideroxyla Humb. & Bonpl. residual bark were identified and evaluated following a chromatographic fractionation. Bark powder was defatted with hexane and crude extract (CE) was obtained by extraction with aqueous acetone (70%). A liquid partition with ethyl acetate was performed to produce an organic...
Adsorbed molecules are involved in many reactions on solid surfaces that are of great technological
importance. As such, there has been tremendous effort worldwide to learn how to theoretically
predict rates for reactions involving adsorbed molecules. Theoretical calculations of rate constants
require knowing both their activation energy and prefactor. Recent...
The load transfer between wood particles and
the matrix was analyzed by observation of the strain patterns
in thin films of high density polyethylene (HDPE)
with embedded wood particles subjected to tensile loading.
Optical measurement techniques based on the digital
image correlation (DIC) principle were employed for quantitative
measurement of...
Finite element analysis was used to study the effective transverse modulus of solid wood for all possible end-grain patterns. The calculations accounted for cylindrical anisotropy of wood within rectangular specimens and explicitly modeled wood as a composite of earlywood and latewood. The effective modulus was significantly reduced by growth ring...
For wood beams, it is often assumed that the neutral axis (NA) is located at the centroid of the beam. This would be the case for isotropic and homogeneous materials but these prerequisites are not valid for wood. The varying grain patterns and knots located throughout wood make wood anisotropic...
Although literacy programs in North African countries vary in method, management approach, and in content emphasis, their discourse is strikingly similar: It focuses too often on learners' deficits and considers the condition of these “illiterate” subjects, i.e. persons lacking the 3Rs, as a “disease” against which a war of eradication...
Current compression perpendicular-to-grain (C-perpendicular to) design values for wood members are based on mean stress obtained from ASTM D143 specimen. The standard ASTM test with metal on wood bearing has limited applicability in modern construction assemblies with C-perpendicular to loading scenarios. Previous work has shown that end-bearing conditions and wood-on-wood...
Wood and wood-based composites are being used extensively in single-family residential dwellings. Therefore, it is important to categorize their response when exposed to elevated temperatures for a sustained period of time. In fire-resistant design for wood structures, the main goal is to ensure that enough structural integrity is maintained, during...