Acoustic wave velocities in standing trees or live softwood species were measured by the time-of-flight (TOF) method. Tree velocities were compared with acoustic velocities measured in corresponding butt logs through a resonance acoustic method. The experimental data showed a skewed relationship…
Keywords: Acoustic velocity, time-of-flight, dilatational wave, Poisson's ratio, standing trees, logs, regression analysis, multivariate analysis, wood grading, trees, acoustic properties, nondestructive testing, wood quality, softwoods, mechanical properties, nondestructive testing, standing trees
Source: Wood and fiber science. Vol. 39, no. 1 (2007): pages 28-38.
This poster presentation reports on recent laboratory work aimed at quantifying the biodegradation process of wood during exposure to natural weathering. Approximately 330 southern pine lumber specimens were placed “above-ground” at an outdoor exposure site near Gulfport, Mississippi for periods up…
Keywords: Wood preservatives, multivariate analysis, near infrared spectroscopy, nondestructive testing, spectrum analysis, deterioration, weathering, preservatives, DDAC, Didecyl-dimethyl ammonium chloride, treated wood, chromated copper arsenate, CCA, durability, southern pine, wood decay, exposure tests
Source: WCTE 2006 : 9th World Conference on Timber Engineering, August 6-10, 2006, Portland, OR, USA : program and abstracts. Portland, Or. : World Conference on Timber Engineering, :  pages.
Research to date on effects of fire exclusion in ponderosa pine (Pinus ponderosa) forests has been limited by narrow geographical focus, by confounding effects due to prior logging at research sites, and by uncertainty from using reconstructions of past conditions to infer changes. For the work…
Keywords: ponderosa pine, Douglas-fir, fire exclusion, forest community structure, multivariate analysis
Source: Forest Ecology and Management 237: 418-428.
Forest environments of the Southern Appalachian Mountains and their characteristic plant communities are among the most varied in the Eastern United States. Considerable data are available on the distribution of plant communities relative to temperature and moisture regimes, but not much…
Keywords: Classification, ecosystems, fertility, geologic formations, logistic regression, moisture, multivariate analysis, ordination, temperature
Source: Res. Pap. SRS-41. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 41 p.
Detailed structural studies on the plant cell wall have traditionally been difficult. NMR is one of the preeminent structural tools, but obtaining high-resolution solution-state spectra has typically required fractionation and isolation of components of interest. With recent methods for dissolution…
Keywords: Nuclear magnetic resonance spectroscopy, plant cell walls, spectrum analysis, lignin analysis, acetylation, polysaccharides, biotechnology, analytic chemistry, multivariate analysis, chemical composition, chemometrics, wood chemistry
Source: Proceedings of the 15th International Symposium on Wood, Fiber and Pulping Chemistry. 2009 June 15-18, Oslo, Norway. (P-105) Oslo, Norway: Congress-Conference AS, 2009:  p.
Two new methods based on FT–Raman spectroscopy, one simple, based on band intensity ratio, and the other using a partial least squares (PLS) regression model, are proposed to determine cellulose I crystallinity. In the simple method, crystallinity in cellulose I samples was determined based on…
Keywords: Cellulose, crystallinity, Raman spectroscopy, FT–Raman, univariate analysis, multivariate analysis, PLS, X-ray, analytic chemistry, chemistry, wood chemistry, Fourier transform spectroscopy, spectrum analysis, correlation, cellulose I, partial least squares, band intensity ratio, standard error
Source: Cellulose. Vol. 17 (2010): p. 721-733.
Early studies of allozyme variation in plant populations suggested that allelic frequencies in some loci vary by geography. Since then, the expectation that allozymes might be useful in describing geographic patterns has generally not been borne out by single locus analyses, except on the broadest…
Keywords: geographic variation, multivariate analysis, trend-surface analysis, transfer risk
Source: New Forests 6: p. 279-309
Monoterpene and isozyme loci, used as markers to study the genetic structure of Scots pine (Pinus sylvestris L.) native to Scotland, showed that the endemic populations are not genetically impoverished, in spite of severe contraction in range and numbers as a result of both natural and…
Keywords: Isozymes, monoterpene inheritance, multivariate analysis, Pinus sylvestris, Pleistocene
Source: New Phytol. 104: p. 703-729
In this work, the effect of temperature on charcoal structure and chemical composition is investigated for four tree species. Wood charcoal carbonized at various temperatures is analyzed by mid infrared spectroscopy coupled with multivariate analysis and by thermogravimetric analysis to…
Keywords: wood charcole, chemical composition, infrared spectroscopy, multivariate analysis, principal component analysis, projection to latent structures, white oak, red maple, sugar maple, silver pmaple, whiskey, maturation, mellowing process, toasting and charring process
Source: J. Agric. Food Chem., Vol. 54: 3492-3497
Near infrared spectroscopy (NIRS) was used to study a set of Southern Yellow Pine boards exposed to natural weathering for different periods of exposure time. This non-destructive spectroscopic technique is a very powerful tool to predict the weathering of wood when used in combination with…
Keywords: Near infrared spectroscopy, multivariate analysis, weathering, southern yellow pine, building materials, service life, deterioration, nondestructive testing, spectrum analysis, durability, exposure tests, wood decay
Source: Metropolis & beyond [electronic resource] : proceedings of the 2005 Structures Congress and the 2005 Forensic Engineering Symposium, April 20-24, 2005, New York, NY. Reston, Va. : American Society of Civil Engineers, c2005: ISBN: 0784407533:  pages.