72 research outputs found
Discriminant Analysis of Geographical Origin of Cork Planks and Stoppers by Near Infrared Spectroscopy
The objective of this study was to assess the potential of visible and near infrared spectroscopy (VIS+NIRS) combined with multivariate analysis for identifying the geographical origin of cork. The study was carried out on cork planks and natural cork stoppers from the most representative cork-producing areas in the world. Two training sets of international and national cork planks were studied. The first set comprised a total of 479 samples from Morocco, Portugal, and Spain, while the second set comprised a total of 179 samples from the Spanish regions of Andalusia, Catalonia, and Extremadura. A training set of 90 cork stoppers from Andalusia and Catalonia was also studied. Original spectroscopic data were obtained for the transverse sections of the cork planks and for the body and top of the cork stoppers by means of a 6500 Foss-NIRSystems SY II spectrophotometer using a fiber optic probe. Remote reflectance was employed in the wavelength range of 400 to 2500 nm. After analyzing the spectroscopic data, discriminant models were obtained by means of partial least square (PLS) with 70% of the samples. The best models were then validated using 30% of the remaining samples. At least 98% of the international cork plank samples and 95% of the national samples were correctly classified in the calibration and validation stage. The best model for the cork stoppers was obtained for the top of the stoppers, with at least 90% of the samples being correctly classified. The results demonstrate the potential of VIS + NIRS technology as a rapid and accurate method for predicting the geographical origin of cork plank and stopper
Non-destructive evaluation techniques and what they tell us about wood property variation
To maximize utilization of our forest resources, detailed knowledge of wood property variation and the impacts this has on end-product performance is required at multiple scales (within and among trees, regionally). As many wood properties are difficult and time-consuming to measure our knowledge regarding their variation is often inadequate as is our understanding of their responses to genetic and silvicultural manipulation. The emergence of many non-destructive evaluation (NDE) methodologies offers the potential to greatly enhance our understanding of the forest resource; however, it is critical to recognize that any technique has its limitations and it is important to select the appropriate technique for a given application. In this review, we will discuss the following technologies for assessing wood properties both in the field: acoustics, Pilodyn, Resistograph and Rigidimeter and the lab: computer tomography (CT) scanning, DiscBot, near infrared (NIR) spectroscopy, radial sample acoustics and SilviScan. We will discuss these techniques, explore their utilization, and list applications that best suit each methodology. As an end goal, NDE technologies will help researchers worldwide characterize wood properties, develop accurate models for prediction, and utilize field equipment that can validate the predictions. The continued advancement of NDE technologies will also allow researchers to better understand the impact on wood properties on product performance
Woods with physical, mechanical and acoustic properties similar to those of Caesalpinia echinata have high potential as alternative woods for bow makers
Genetic parameters for growth, wood density and pulp yield in Eucalyptus globulus
Genetic variation and co-variation among the key
pulpwood selection traits for Eucalyptus globulus were
estimated for a range of sites in Portugal, with the aim of
improving genetic parameters used to predict breeding
values and correlated response to selection. The trials
comprised clonally replicated full-sib families (eight trials)
and unrelated clones (17 trials), and exhibited varying
levels of pedigree connectivity. The traits studied were stem
diameter at breast height, Pilodyn penetration (an indirect
measure of wood basic density) and near infrared reflectance
predicted pulp yield. Univariate and multivariate
linear mixed models were fitted within and across sites, and estimates of additive genetic, total genetic, environmental
and phenotypic variances and covariances were obtained.
All traits studied exhibited significant levels of additive
genetic variation. The average estimated within-site narrowsense
heritability was 0.19±0.03 for diameter and 0.29±
0.03 for Pilodyn penetration, and the pooled estimate for
predicted pulp yield was 0.42±0.14. When they could be
tested, dominance and epistatic effects were generally not
statistically significant, although broad-sense heritability
estimates were slightly higher than narrow-sense heritability
estimates. Averaged across trials, positive additive
(0.64±0.08), total genetic (0.58±0.04), environmental
(0.38±0.03) and phenotypic (0.43±0.02) correlation estimates
were consistently obtained between diameter and
Pilodyn penetration. This data argues for at least some form
of pleiotropic relationship between these two traits and that
selection for fast growth will adversely affect wood density
in this population. Estimates of the across-site genetic
correlations for diameter and Pilodyn penetration were
high, indicating that the genotype by environment interaction
is low across the range of sites tested. This result
supports the use of single aggregated selection criteria for
growth and wood density across planting environments in
Portugal, as opposed to having to select for performance in
different environment
Use of near infrared spectroscopy to distinguish carbonization processes and charcoal sources
A review of recent application of near infrared spectroscopy to wood science and technology
Salvaged lumber for Structural Mass Timber Panels: Manufacturing and Testing
Portland, OR, was the first US city to implement a deconstruction ordinance in 2016. Although salvaged lumber can have a high demand, the market for small-sized lumber from deconstructed dwellings is near saturation. New applications for this material are required for market development, industry diversification, and increasing deconstruction practices. Mass timber products such as cross-laminated timber (CLT) could be a new market for this material, but presently there is minimal information qualifying the performance of mass timber panels made with salvaged lumber. Three, full-sized 3-ply experimental layups, with varying amounts of salvaged/recycled wood content, were manufactured and tested to characterize panel properties. Manufacturing processes and testing methods followed ANSI/APA PRG 320-2018; Standard for Performance Rated Cross-Laminated Timber. Each panel layup had three replicates for nine panels in total. Panels measured 1.1 m by 2.3 m by 3 plys, and test results were used to calculate the effective flatwise bending moment resistance ((FbS)eff), effective flatwise bending stiffness ((EI)eff) effective shear stiffness in flatwise bending ((GA)eff), flatwise shear resistance (Vs), percent wood failure (WF%), and percent delamination (Delamination %). Results were compared with E3 grade 3-ply CLT panels made in the United States and indicated that salvaged lumber could be used as feedstock for mass timber panels in core layers or all layers. All panel layups passed benchmarks for (FbS)eff and (EI)eff benchmarks with values greater than PRG320. Panels having salvaged lumber in core layer also met Vs benchmarks. Furthermore, all panels passed examination for WF% but struggled to meet delamination requirements. Possibilities exist for better performance if panels were made in a commercial setting. This research shows salvaged lumber has promise for manufacturing structural CLT, but more research and a larger samples size is needed to verify findings
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