4 research outputs found
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Application of Infrared Spectroscopy for Determination of Wood Natural Durability
Natural durability remains one of the most attractive characteristics of wood, and helps wood obtain a premium price. A worldwide shift towards the use of younger trees from intensively managed forests has created greater concerns about wood quality, especially the wood’s resistance to fungi and insects. Wood durability is assessed using a variety of standards. Some standards are based on destructive methods that measure weight loss after exposure to wood degrading organisms. These tests are useful but there are concerns about variabilities in durability classifications according to different testing methods. Furthermore, durability can be heavily influenced by variations within and between trees, sites, regions, genetic origin, and age. Thus, there is a need for a faster, non-destructive and economically viable technique for screening wood durability. Fourier transform infrared spectroscopy with attenuated total reflectance (ATR-FTIR) and near infrared spectroscopy (NIR), with chemometrics analysis was explored for classifying wood durability. The extractive contents of Alaska yellow cedar (Callitropsis nootkatensis) and western juniper (Juniperus occidentalis) were investigated to understand the variability that existed between and within trees, and the relationships between brown-rot decay (Gloeophyllum trabeum and Rhodonia placenta), termite (Reticulitermes flavipes) resistance, and the spectroscopic results were examined. FT-IR showed sensitivity in detecting to one of the extractive concentrations (carvacrol) as differences were observed on 3% concentration. The majority of the Alaska yellow cedar and western juniper samples were classified as resistant to highly resistant against decay fungi and termites. A moderate to poor correlation between extractives and mass loss to wood biodegradations agents (fungi and termites) was observed, indicating the possibility for other factors may contribute to wood superior durability. Chemometrics analysis using principal component analysis (PCA) and hierarchical cluster analysis (HCA) on the spectral data was unable to accurately classify wood based on their durability. Nevertheless, results suggest FT-IR and NIR can be used for analyzing wood extractives, as well as the possibility for producing more accurate predictions on species with greater variability in durability
ATR-FTIR Study of Alaska Yellow Cedar Extractives and Relationship with Their Natural Durability
New approaches for assessing wood durability are needed to help categorize decay resistance as timber utilization shifts towards plantations or native forest regrowth that may be less durable than original native forest resources. This study evaluated attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy combined with principal component analysis (PCA) for distinguishing between groups of Alaska yellow cedar (Cupressus nootkatensis) wood for susceptibility to two decay fungi (Gloeophyllum trabeum and Rhodonia placenta) and the eastern subterranean termite (Reticulitermes flavipes). Alaska yellow cedar durability varied with test organisms, but the majority of samples were highly resistant to fungal and termite attack. Weight losses and extractives yield using sequential extractions (toluene:ethanol > ethanol > hot water) showed moderate to weak relationships. PCA analysis revealed limited ability to distinguish amongst levels of wood durability to all tested organisms. The absence of non-resistant samples may have influenced the ability of the chemometric methods to accurately categorize durability
ATR-FTIR Study of Alaska Yellow Cedar Extractives and Relationship with Their Natural Durability
New approaches for assessing wood durability are needed to help categorize decay resistance as timber utilization shifts towards plantations or native forest regrowth that may be less durable than original native forest resources. This study evaluated attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy combined with principal component analysis (PCA) for distinguishing between groups of Alaska yellow cedar (Cupressus nootkatensis) wood for susceptibility to two decay fungi (Gloeophyllum trabeum and Rhodonia placenta) and the eastern subterranean termite (Reticulitermes flavipes). Alaska yellow cedar durability varied with test organisms, but the majority of samples were highly resistant to fungal and termite attack. Weight losses and extractives yield using sequential extractions (toluene:ethanol > ethanol > hot water) showed moderate to weak relationships. PCA analysis revealed limited ability to distinguish amongst levels of wood durability to all tested organisms. The absence of non-resistant samples may have influenced the ability of the chemometric methods to accurately categorize durability
Anatomical and physical properties of three lesser-known timber species from Malaysia
The purpose of this study is to determine the anatomical and physical
properties of three lesser-known Malaysian timber species, i.e., mahang
(Macaranga hosei), medang (Litsea costalis), and terap (Artocarpus
scortechinii). Correlation factors that influenced the density and
shrinkage were also discussed. From the results obtained, terap wood
had the longest fibre (1421 µm), followed by medang (1309 µm), and
mahang (1161 µm). Terap, medang, and mahang were categorized as
having very thin fibres. The density of terap, medang, and mahang had
average values of 504 kg/m 3 , 485 kg/m 3 , and 474 kg/m 3 , respectively. In
addition, terap wood also showed the highest shrinkage, followed by
mahang and medang wood. This present study showed that the density
was significantly influenced by the fibre length, fibre wall thickness,
vessel diameter, and number of vessels. In addition, the shrinkage was
highly correlated with the density. In conclusion, mahang, medang, and
terap wood could be an alternative raw material to fulfill demand in wood-
based industries