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Nondestructive methods have been used to predict different technological characteristics of wood. The study evaluated multivariate PLS (partial least squares) models for Klason lignin prediction in forest species native to the Amazon using Fourier transform near-infrared spectroscopy (FT-NIR). Samples of 40 species of commercial wood (Amazonas/Brazil) were obtained in the form of discs at breast height, and wedges in the sapwood-pith direction were extracted. Lignin quantification (reference) was performed, and NIR spectra were obtained on the surface of the radial plane of the samples. A matrix was built with reference data × spectra, and PLS models were built and evaluated. The combination of chemometric data produced 150 predictive models in the bands 7,400–5,823, 7,332–5,187, and 7,000–4,100 cm−1. Using figures of analytical merit (precision), 28 models were selected when they presented R2c > 0.85 (calibration determination coefficients) and R2v > 0.50 (validation). The PLS 4 model (2nd derivative, 8 latent variables) was considered the most robust in the study (R2v = 0.93; SE = 0.01%, standard error; RMSEP = 3.52%, root mean squared error of prediction). The results indicate the use of FT-NIR spectroscopy to predict Klason lignin in Amazonian woods, confirming the efficiency of the tool in producing fast, accurate, nondestructive results without the generation of chemical residues, where this estimate can be useful for studies of forestry, ecology, forest management, and wood technology. [ABSTRACT FROM AUTHOR]

Costa Rica produces a considerable, important quantity of wood residues. This waste can be pyrolyzed to produce charcoals as main products that can be effectively used as an energy source or to immobilize carbon for soil treatment. However, there is a lack of information about the pyrogenic carbonaceous materials (PCMs), such as charcoal or biochar, obtained at different pyrolysis temperatures. Hence, this study aimed to evaluate the quality of PCMs (physical, mechanical, ultimate analysis, and FTIR analysis) and charcoal characteristics (energetic properties and thermogravimetric analysis—TGA) and biochar characteristics (conductivity, pH, initial contact angle, and wetting rates) for four tropical wood residues produced in five temperatures (300 °C, 350 °C, 400 °C, 450 °C, and 500 °C). In general, pyrolysis temperature between 450 °C and 500 °C produced charcoals with lower values of density, moisture content, compression strength, volatiles, H and O content, and higher values of C and ash contents, conductivity, pH, initial contact angle, and wetting rates. FTIR and TGA analyses show that celluloses and lignin are pyrolyzed at these temperatures, so these temperatures are recommended. The range of 300–350 °C is not recommended, as these parameters were inverse. Multivariate analysis shows that (i) PCMs obtained at lower temperatures (300–350 °C) from Dipteryx panamensis, Hieronyma alchorneoides, and Tectona grandis belong to a cluster with poorer properties, indicating that these temperatures are not adequate for pyrolysis of these species; (ii) all the PCMs obtained from Gmelina arborea were grouped into one cluster, suggesting different PCM quality; and (iii) the PCMs produced from D. panamensis, H. alchorneoides, and T. grandis at 400–500 °C were grouped into another cluster with better properties, suggesting this pyrolysis temperature range as the best for these species. [ABSTRACT FROM AUTHOR]

The infrared spectrum carries the so-called fingerprint of a plant, a characteristic that can help the identification of wood from an integrative perspective. Fourier-transform near-infrared spectroscopy (FT-NIRS) was evaluated for its potential use in the taxonomic identification of natural fallen trees from the Amazon rainforest (Myristicaceae). Trees found on the forest floor (Amazonas, Brazil) were surveyed, and eight individuals were selected for the study. The material was removed from the trunk for anatomical identification based on xylem structure and obtaining NIR spectra (10,000 to 4,000 cm-1). A total of 1,080 spectra were collected and used in the multivariate analysis. Absorption bands in the NIR region and chemometrics (calibration models) were used to interpret the spectra, which indicated similarity trends at the genus and species levels. Linear discriminant analysis (LDA) was able to differentiate Iryanthera ulei and Virola (five species), which were misclassified in the field as a single species (Virola sp.). The accuracy of the results obtained by chemometric models (LDA 7 and 14) indicates the robustness of NIR spectroscopy, which can be used as a new tool in the integrative taxonomy of plant material from tropical forests that are difficult to identify and can analyzing many tests quickly and securely. Study Implications: The taxonomic identification of natural fallen trees found on the floor of tropical forests is quite complex given the lack of flowers, fruits, and leaves in field collection. Fourier-transform near-infrared spectroscopy demonstrated its capability to distinguish between wood samples from fallen trees belonging to the Myristicaceae family. The chemometric model successfully discriminated the samples, which had been erroneously lumped together in the field under the single species designation of Virola sp. This technique has been previously overlooked for providing differentiation. Our study highlights its efficacy to address misclassifications and allow taxonomic identification. [ABSTRACT FROM AUTHOR]

Why was the work done: Cachaça, the oldest distilled beverage in the Americas, has great historical and cultural significance. A review of cachaça production is important to preserve tradition, standardise industry processes, promote innovation and quality. This review offers a comprehensive overview of current knowledge and advancements in cachaça production, covering regulation, process control, product quality and future developments. What are the main findings: The production of Cachaça observes well defined regulations, with its processes encompassing both field and industrial practice. The review focuses on sugar cane cultivation, fermentation, distillation, and ageing in wooden barrels. It underscores the significance of regional factors such as climate, soil, and the varirty of sugar cane in shaping the sensory profile of cachaça. While a range of sugar cane cultivars have been developed and grown in different environments, further research on the adaptation of sugar cane crop is necessary. Fermentation of cachaça is spontaneous utilising the microbiota in the sugar cane juice. However, the use of wild sugar cane yeasts, complemented with commercial strains is increasingly used by producers. With regard to distillation, production of the spirit using copper still pots and ageing in tropical wood barrels remain prevalent in the industry. Why is the work important: This review contributes to ongoing efforts to enhance the quality of cachaça. Whilst the importance of traditional production methods is recognised, this review embraces advancements in technology coupled with insights to future perspectives. [ABSTRACT FROM AUTHOR]

The study characterized the technological properties of eight woods from small-diameter forest species with vast occurrence in the Central Amazon (Amazonas/Brazil), as a potential for indication in a forest exploration plan. Samples were obtained from the managed area, and 24 trees (diameter at breast height ≤ 50 cm) were used in chemical and physical–mechanical determinations. Among the eight species studied, the wood matá-matá yellow (Eschweilera odora) had the highest concentration of extractives and polyphenols (7.08 and 2.63%), while piãozinho (Microdropsis scleroxylon) had the highest lignin content (34.80%). For the physical–mechanical properties, the basic density ranged from 0.56 for ingá-white (Inga alba), and 0.93 g/cm3 for piãozinho, and matá-matá black (Eschweilera truncata) showed the highest static bending stiffness of 17,350 MPa and static bending strength of 173.93 MPa. The multivariate analysis (principal component analysis) indicated the formation of five groups, and the matá-matá black grouping was characterized by higher values of ash, static bending stiffness, and strength. The quality of the wood of the studied species indicates use in the forest industry (structural use, energy, and engineered wood products), where new species can be included in the sustainable forest management of the Amazon. [ABSTRACT FROM AUTHOR]

Costa Rica produces a considerable, important quantity of wood residues. This waste can be pyrolyzed to produce charcoals as main products that can be effectively used as an energy source or to immobilize carbon for soil treatment. However, there is a lack of information about the pyrogenic carbonaceous materials (PCMs), such as charcoal or biochar, obtained at different pyrolysis temperatures. Hence, this study aimed to evaluate the quality of PCMs (physical, mechanical, ultimate analysis, and FTIR analysis) and charcoal characteristics (energetic properties and thermogravimetric analysis—TGA) and biochar characteristics (conductivity, pH, initial contact angle, and wetting rates) for four tropical wood residues produced in five temperatures (300 °C, 350 °C, 400 °C, 450 °C, and 500 °C). In general, pyrolysis temperature between 450 °C and 500 °C produced charcoals with lower values of density, moisture content, compression strength, volatiles, H and O content, and higher values of C and ash contents, conductivity, pH, initial contact angle, and wetting rates. FTIR and TGA analyses show that celluloses and lignin are pyrolyzed at these temperatures, so these temperatures are recommended. The range of 300–350 °C is not recommended, as these parameters were inverse. Multivariate analysis shows that (i) PCMs obtained at lower temperatures (300–350 °C) from Dipteryx panamensis, Hieronyma alchorneoides, and Tectona grandis belong to a cluster with poorer properties, indicating that these temperatures are not adequate for pyrolysis of these species; (ii) all the PCMs obtained from Gmelina arborea were grouped into one cluster, suggesting different PCM quality; and (iii) the PCMs produced from D. panamensis, H. alchorneoides, and T. grandis at 400–500 °C were grouped into another cluster with better properties, suggesting this pyrolysis temperature range as the best for these species.

Charcoal production from woody species from fast-growth plantations has gained importance in a variety of uses. The objective of the present work is to determine the density, compression resistance, moisture content (MC), gross calorific value (GCV), ash and volatile content, chemical modification by Fourier-transform infrared spectroscopy (FTIR) spectrum and thermogravimetric degradation of charcoal produced by pyrolysis at 450°C from sixteen tropical woods from fast-growth plantations in Costa Rica. The results showed values of MC of 2.65–7.72%, density of 0.15–0.39 g/cm3, compression strength of 19.07–82.92 kg/cm2, ash content of 0.26–7.98%, GCV of 32.10–24.29 MJ/kg, volatile matter of 22.45–33.34%, fixed carbon of 60.36–68.91%, carbon of 78.51–69.43%, hydrogen of 4.15–3.55%, oxygen of 17.25–26.56%, O/C ratio of 0.17–0.29 and H/C ratio of 0.56–0.64. FTIR spectrum evidenced the presence of OH, CH2, C = O, C-O-C groups, common in pyrolyzed biomass. TGA analysis showed two types of behavior, which differ in that one group presents two peaks between 200°C and 800°C. The multivariate analysis by principal components (PC) applied to charcoal characteristics measured in sixteen species showed that the variations of these characteristics can be explained up to 99% and four groups were established. [ABSTRACT FROM AUTHOR]

The relaxation of growth stress in trees from plantation forests of tropical areas is manifested in the quality of wood after the sawing and the relaxation of drying stress is expressed during the drying process, producing low wood quality. The present study aims to evaluate the lumber quality in logs by heating and steaming application before sawing as pretreatment to reduce growth stress and the application of steaming step during drying of Dipteryx panamensis (almendro) and Hieronyma alchorneoides (pilón) wood. The results showed that the variation of moisture content and drying rate concerning drying time in wood from logs steamed before or during drying led to a quick increase in the drying rate and a decrease in the moisture content. The steaming application to the logs or during drying decreased the incidence and magnitude of drying defects and increased the quality of dried lumber, especially bow, split, crook, and check defects. [ABSTRACT FROM AUTHOR]

This study explores the integration of legal timber harvesting and conservation efforts in the Amazon, repurposing wood processing waste into biofuel through pelletization to meet environmental standards and reduce diesel dependence in isolated systems. The research focuses on pellets derived from six Amazonian species managed sustainably: Peltogyne lecointei (S1), Erisma uncinatum (S2), Martiodendron elatum (S3), Handroanthus incanus (S4), Dipteryx odorata (S5), and Allantoma decandra (S6). Four blends (B1: S5 and S6; B2: all species; B3: S1, S3, S4 and S5; B4: S2 and S6) with different species combinations are pelleted at 8 % and 10 % moisture content. Pellet characteristics are compared with ISO 17225-2 standards [1], including calorific value, bulk density, water content, dimensions, ash content, mechanical durability, and fines. Although blends B1, B2, and B3 meet A1-criteria, none achieve the required 96.5 % mechanical durability. B3, pelleted with 10 % moisture content, exhibits the highest durability (90.4 %). Pelletization enhanced the bioenergy density by 255 % and showed a bioenergy index up to 12.50 GJ m−3. The produced pellets reported a potential CO 2 emissions mitigation of up to 1259.38 kgCO 2 eq by replacing diesel fuel. However, the blends do not meet the sulfur (>0.05 %) content requirement for industrial and domestic applications, deserving further investigation into pre-treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Magnetic wood is a composite material that achieves harmony between both woody and magnetic functions through the active addition of magnetic characteristics to the wood itself. In addition to showing magnetic characteristics, magnetic wood offers low specific gravity, humidity control and acoustic absorption ability. It has potential for broad applications in the fields of electromagnetic wave absorption, electromagnetic interference shielding, furniture, etc. This work reports on the synthesis of Fe3O4 nanoparticles (NPs) in wood from three tropical species (Pinus oocarpa, Vochysia ferruginea and Vochysia guatemalensis) using a solution of iron (III) hexahydrate and iron (II) chloride tetrahydrate with a molar ratio of 1.6:1 at a concentration of 1.2 mol/L ferric chlorate under 700 kPa pressure for 2 h. Afterward, the wood samples were impregnated with an ammonia solution with three different immersion times. The treated wood (wood composites) was evaluated for the weight gain percentage (WPG), density, ash content and Fe3O4 content by the Fourier transform infrared spectroscopy (FTIR) spectrum, X-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The results show that the species P. oocarpa had the lowest values of WPG, and its density decreased in relation to the untreated wood, with lower ash and Fe3O4 NP content. The XRD and some FTIR signals associated with changes in the wood component showed small differences from the untreated wood. Fe3O4 NPs presented nanoparticles with the smallest diameter of (approx. 7.3 to 8.5 nm), and its saturation magnetization (Ms) parameters were the lowest. On the other hand, V. guatemalensis was the species with the best Ms values, but the wood composite had the lowest density. In relation to the different immersion times, the magnetic properties were not statistically affected. Finally, the magnetization values of the studied species were lower than those of the pure Fe3O4 nanoparticles, since the species only have a certain amount of these nanoparticles (NPs), and this was reflected proportionally in the magnetization of saturation. [ABSTRACT FROM AUTHOR]

ABSTRACT Agroforestry systems (AFSs) integrate, through sustainable practices, agricultural and forest crops for the production of wood and food, providing environmental services, and conserving biodiversity. The freijó (Cordia goeldiana) has potential for cultivation in the Amazon for timber purposes, but data on the characteristics of its wood produced in AFSs are scarce. Our objective was to determine the physical-mechanical properties and suggest technological applications of freijó wood produced in a multi-stratified AFS established in the state of Rondônia, Brazil in 1996. Agricultural and forest species were established in the AFS in double rows with 5.0-m x 2.5-m spacing. Three 19-year-old freijó trees were harvested for chemical, physical (density and dimensional stability), and mechanical (compression, static bending, Janka hardness, and shear strength) characterization of the wood. The wood presented a chemical composition similar to tropical hardwoods, was moderately heavy (582.63 kg m-3), and had high dimensional stability in comparison with other consecrated woods on the market (longitudinal, radial, and tangential retraction = 0.25, 4.27, and 6.83%, respectively). The values determined for parallel (32.32 MPa) and perpendicular compression (8.02 MPa), specific strength (55.32 MPa kg-1 m-3), parallel (2373.33 N) and perpendicular Janka hardness (2326.67 N), strength to static bending (63.5 MPa), and shear (5.94 MPa) were similar to the values observed in other high-density tropical woods grown in either monoculture plantations or natural forests. The wood under study is suitable for manufacture of high-value-added products, such as fine furniture, residential floors, musical instruments and structural pieces.

ABSTRACT The recent interest in constructing high and robust wooden structures has stimulated the investigation of physical and mechanical properties as well as their correlation with other important parameters of the material of tropical species like the Vatairea sp., whose popular name is angelim-amargoso, used especially in roof structures with large spans. The Brazilian Standard for wood constructions recommends using linear models to correct or estimate the strength and/or stiffness of wood correlated with moisture content and also provides the classification of hardwoods according to their characteristic strength. However, because wood is a natural, heterogeneous, and anisotropic material, certain properties may not be affected by significant differences in moisture content. Therefore, in this study, the influence of moisture content on fifteen physical and mechanical properties of Vatairea sp. wood was investigated through its characterization. The tests were carried out on 12 specimens for each property and two groups: with the moisture content of 12% and at the fiber saturation point. The Anderson-Darling test was performed to verify the results’ normality and the analysis of variance (ANOVA) to analyze the influence of moisture content on these properties. In addition, the wood was classified according to the strength classes of the Brazilian Standard, and the strength and stiffness were estimated according to the linear models proposed by the same norm. The estimated results were compared with the experimental ones through the difference calculation and percentual error of the values. It was concluded that most properties were not affected by the moisture content, and the most significant errors obtained in the estimates were for properties that were significantly influenced by the moisture content.

The great diversity of tropical wood species makes it difficult to obtain information about their technological properties. The present work employed ultrasound to estimate the physical and mechanical properties of four wood species: African mahogany (Khaya senegalensis), 'freijó' (Cordia goeldiana), 'paricá' (Schizolobium amazonicum), and teak (Tectona grandis). Nineteen-year-old adult trees were selected and harvested from an agroforestry system (AFS) located in the Brazilian Amazon. From the harvested trees, 1.5 m logs were sawn and test specimens were obtained for physical-mechanical assays. The ultrasound propagation speed (V0) and the dynamic modulus of elasticity (Ed) were obtained from applying ultrasound longitudinally in wood samples. Values of V0 decreased from the lightest wood (paricá) to the heaviest (African mahogany), and Ed presented the opposite behavior. For the physical properties, the coefficient of determination (R2) ranged from 12 to 35% and the best linear regression models were fitted for the basic density, having V0 and Ed as independent variables. For the mechanical properties, the values of R2 varied from 18 to 63% and higher correlations were found between parallel-to-grain compression strength and Ed, and rigidity, static bending and Ed. Ultrasound presented the potential to estimate the properties of tropical wood species from the ASF. [ABSTRACT FROM AUTHOR]

Clarinets are made with a variety of materials, e.g., plastic, graphite, porcelain, or even metal. However, the most commonly used material to make clarinets is wood. Today, African granadilla or African blackwood (Dalbergia melanoxylon) is the most popular and most widely used species by leading international companies in terms of clarinet production, because of its high density, color, fine texture, and exceptional durability. This species is also used to manufacture flutes, oboes, and bagpipes, making African blackwood one of the most valuable tree species in the world. However, the focus on the usage of a single species puts considerable pressure on a rare and endangered wood species. Therefore, this work aims to identify viable alternatives to African blackwood in terms of manufacturing clarinets as well as providing a similar combination of instrument characteristics that musicians and companies believe contribute to the value of the instrument, e.g., acoustics, aesthetics, and price. [ABSTRACT FROM AUTHOR]

The illegal logging of valuable tree species is mainly motivated by a global market that consumes logs, lumber, veneers, and furniture. The use of objective techniques to identify species and the effects of international initiatives such as CITES rules contributes to controlling trade, exploitation, and smuggling of these products. The anatomical identification of wood veneers is limited due to the loss of several anatomical characters in the production process of the veneers. For this reason, we propose the Near-Infrared Spectroscopy technique associated with chemometric tools for the discrimination of wood veneer of woods with similar general characters: Swietenia macrophylla King (mahogany), Carapa guianensis Aubl. (andiroba), Cedrela odorata L. (cedro), Micropholis venulosa Pierre (curupixá), and Hymenaea coubaril L. (jatobá) using a portable spectrometer.The development of the discrimination models was performed using the PLS-DA (Partial Least Squares for Discriminant Analysis) algorithm. The detection and subsequent exclusion of outliers were performed based on Hotelling T2, Q residuals, and errors in estimating class values. The PLS-DA models showed an efficiency between 96.5% and 100% in the samples' discrimination among the five forest species. In conclusion, the portable NIRS technology and the PLS-DA models were suitable for the rapid identification and discrimination of the wood veneers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Traceability of a legal commercial cedar shipment based on NIRS. • Comparison of cargo at origin (Amazon region) and destination (>3100 km away). • The cedar cargo has a 76.2% likelihood of being the original shipment. • Batches of cedar from different origins showed a probability range of 5.7–20.8%. • Batches from different species showed a probability range of 0–21.9%. The traceability of commercial timber is one of the preventive measures to combat illegal timber trade. Even though there are several methods to determine wood species or its origin, there is no standard procedure established yet. Furthermore, traceability is a difficult problem, and there is a lack of studies about the subject. NIRS technology combined with multivariate data analysis has proved to be a fast and efficient methodology for species identification, as well as a promising tool for geographical origin determination. This study aimed to track a commercial cargo of 19,114 m3 of Cedrela odorata L. boards from the legal extraction concession area in the Jamari National Forest (Amazon region) to the final dealer located in the city of Ubatuba (São Paulo), a distance of 3100 km by land. The cargo was packed and transported by truck to protect it from weather. The NIR spectra obtained at the origin were used to create a data driven soft independent modelling by class analogy (DD-SIMCA model), which was applied to the spectra obtained at the destination of the cargo. The compatibility rate found by the model using all sampled batches was 76 %, which means that most of the samples were within the model acceptance area and were highly compatible with the initial cargo. When applied to C. odorata samples from other origins/cargos, the number of samples within the acceptance area did not go over 21 %. When testing the model on other wood species (Erisma uncinatum Warm. Swietenia macrophylla King, and Micropholis melinoniana Pierre), this rate was no more than 22 %. These latter values corroborate the practicality, precision, and reliability of NIRS for in-field tracking of wood cargo. [ABSTRACT FROM AUTHOR]

Magnetic wood is a composite material that achieves harmony between both woody and magnetic functions through the active addition of magnetic characteristics to the wood itself. In addition to showing magnetic characteristics, magnetic wood offers low specific gravity, humidity control and acoustic absorption ability. It has potential for broad applications in the fields of electromagnetic wave absorption, electromagnetic interference shielding, furniture, etc. This work reports on the synthesis of Fe3O4 nanoparticles (NPs) in wood from three tropical species (Pinus oocarpa, Vochysia ferruginea and Vochysia guatemalensis) using a solution of iron (III) hexahydrate and iron (II) chloride tetrahydrate with a molar ratio of 1.6:1 at a concentration of 1.2 mol/L ferric chlorate under 700 kPa pressure for 2 h. Afterward, the wood samples were impregnated with an ammonia solution with three different immersion times. The treated wood (wood composites) was evaluated for the weight gain percentage (WPG), density, ash content and Fe3O4 content by the Fourier transform infrared spectroscopy (FTIR) spectrum, X-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The results show that the species P. oocarpa had the lowest values of WPG, and its density decreased in relation to the untreated wood, with lower ash and Fe3O4 NP content. The XRD and some FTIR signals associated with changes in the wood component showed small differences from the untreated wood. Fe3O4 NPs presented nanoparticles with the smallest diameter of (approx. 7.3 to 8.5 nm), and its saturation magnetization (Ms) parameters were the lowest. On the other hand, V. guatemalensis was the species with the best Ms values, but the wood composite had the lowest density. In relation to the different immersion times, the magnetic properties were not statistically affected. Finally, the magnetization values of the studied species were lower than those of the pure Fe3O4 nanoparticles, since the species only have a certain amount of these nanoparticles (NPs), and this was reflected proportionally in the magnetization of saturation.

Drywood termites, Cryptotermes brevis (Walker) (Isoptera: Kalotermitidae), are eusocial insects living and foraging in groups inside pieces of wood, in which they perform a suite of behavioral traits ranging from individual to coordinated group activities. Vibroacoustic cues play important roles in behavioral mediation during defense and foraging activities. However, termite societies also exhibit other relevant behaviors, including substrate selection for colony establishment, which has received little attention. Therefore, we tested the hypothesis that vibrational cues produced by termites inside pieces of drywood influence wood recruiting of conspecifics using dichotomous choice tests. In addition, we assessed whether the choice affects colony success (i.e., termite survival and wood consumption). Two behavioral activities were recognized among drywood termites colonizing wood galleries – walking and chewing. However, only the chewing cues overcome background noise, allowing acoustic signal characterization and playback tests; thus, they were the focus of our study. Overall, drywood termite groups exhibit random choice among wood‐testing unities, indicating that the chewing cues from the natural and/or playback signals are not used as a social trigger to mediate conspecific recruiting for wood preference and colonization. Nonetheless, the establishment of termite colonies in infested vs. non‐infested wood pieces led to better termite performance in the former, exhibiting higher wood consumption and survival. [ABSTRACT FROM AUTHOR]

Ghana has a long history as a major supplier of high-value hardwood timber and wood products to many countries. The research seeks to assess the effects of tropical wood leachates to aquatic organisms. Hence, five wood samples were selected; Mahogany (Khaya ivorensis), Cedrela (Cedrela odorata), Emire (Terminalia ivorensis), Wawa (Triplochiton scleroxylon) and Ceiba (Ceiba pendandra) from Oboyow forest reserve in Eastern Region- Ghana to assess their toxicity to aquatic organisms. Toxicity tests: Algal (Desmodesmus subspicatus) Duckweed (Lemna minor) and crustacean (Daphnia magna) were carried out using exposures to concentrations of 20, 30, 45, 67 and 100% v/v wood leachate in control media. The high levels of phenols measured in the various wood leachates was the main cause of toxicity. The percentage median Inhibition Concentration (%IC50) of the various wood leachate, ranged from 21.5 - 55.6% with mahogany exhibiting the highest toxicity and wawa the lowest. All the wood leachates were toxic to the aquatic organisms. The %IC50 showed both confirmed and potential toxicity among the various wood leachates and established that there was significant difference between various wood leachate toxicity.

Hyperspectral and colorimetric patterns were determined from anatomical and physical aspects for the characterization of dry Peltogyne purpurea Pittier wood from natural forest trees. A sample of 24 P. purpurea wood discs was taken and anatomical characteristics (density and diameter of vessels, percentage of solitary vessels), wood density, colour (CIELab) and hyperspectral reflectance in the range of 310 to 1 100 nm in the dry wood, both in sapwood and heartwood section, were determined. Significant anatomical differences were found between sapwood and heartwood; a higher presence of solitary vessels was found in sapwood (34.28%) but with a vessel density of 27.07 pores mm'2 and diameter of 148.53 im In the colorimetry analysis, brightness and b* (yellowing) were higher in sapwood, but with significantly lower values in a* (redness), thus generating a total color difference (higher than 14.55). As regards reflectance, three significant differentiation points were found between both sections, which were at 460, 580 and 1 020 nm; when correlating these three segments, no correlation was found with the anatomical aspects, but with the density of the wood (higher than 0.69), at the color level no relationship was found with the color parameter L* (brightness), while a* only showed inverse correlations at 580 nm and linear ones with b* at 580 nm. In this study no colorimetric relationships with anatomical aspects were found. [ABSTRACT FROM AUTHOR]

The fiber saturation point (FSP) is an important parameter of wood material, related to dimensional stability and variations of mechanical performance. This paper investigated the FSP values of 15 tropical Brazilian wood species covering all strength classes of the Brazilian standard code. An additional goal was to estimate FSP value based on the wood's apparent density. The FSP values were determined by measuring the wood specimen dimensions during moisture content reduction from the saturated state. Wood densities at 0% and 12% moisture contents and basic density were determined according to the Brazilian standard code. The average FSP for all wood species was 21.6% moisture content. Among density values, good correlations were observed, and a multivariate regression model for FSP estimation based on wood densities presented a coefficient of determination equal to 13.07%. There was no correlation between FSP and wood densities, suggesting that this parameter is almost constant regardless of the wood species. [ABSTRACT FROM AUTHOR]

Wood residues hold great potential for the development of composites. However, reinforcing wood requires modifications to enhance its adhesion to the polymeric matrix. In thermopressing, composites reinforced with wood are processed over a wide range of moisture levels. Nevertheless, there are limited studies on how varying this parameter influences the mechanical properties of these composites. This research provides valuable insights into how the moisture content present in wood reinforcement during the thermopressing process affects the adhesion of the composite through the modulus of rupture, a contribution not previously found in the literature. Therefore, our study aims to investigate the effects of different NaOH concentrations (5% and 10%) and the moisture content levels (3% and 12%) during thermopressing on the modulus of rupture of polyurethane-based composites. We analyzed three types of tropical wood residues from the Amazon, both with or without mercerization treatment, using thermal (TG/DSC), structural (XDR and FTIR), and morphological (SEM) characterizations. Subsequently, we evaluated the impact of moisture content on the modulus of rupture. The concentration of NaOH modifies the thermal, structural, and morphological characteristics of the wood residues, but these modifications were more effective in the composite when the moisture content of the fibers was low (3%). Reducing the moisture content of the reinforcement increased the resistance and the modulus of rupture of the composites made from Louro Itaúba (from 2 to 9 MPa), Louro Gamela (from 12 to 16 MPa), and Massaranduba (from 3 to 11 MPa). Therefore, mercerization alone was insufficient to boost the modulus of rupture of polymeric composites. Instead, the control of moisture content emerged as the crucial factor during the thermopressing process. [Display omitted] • Amazon wood waste holds potential for composite development. • The correlation between wood mercerization and moisture content in composites was studied. • Wood reinforcement with 3% moisture adheres better to matrix than 12% moisture. • Lowering the wood moisture content increased the modulus of rupture. [ABSTRACT FROM AUTHOR]

The aims of this work were to determine the color change and physical–mechanical properties of polystyrene glulam from three tropical wood species. Wood laminas were cut from logs harvested from a young plantation forest of manii (Maesopsis eminii), mangium (Acacia mangium), and rubber-wood (Hevea brasiliensis). The laminas were impregnated with monomer styrene that was polymerized using potassium peroxy-disulfate as a catalyst and heat. Three-layer glulam was constructed from the polystyrene laminas, using isocyanate glue and cold press. For comparison purposes, three-layer untreated glulam and solid wood samples were prepared. The results showed that the color change of polystyrene glulam was very small compared with untreated glulam. Polystyrene glulam had the highest density, while the density of untreated glulam did not differ from that of the solid wood. The moisture content of all products was matched to the environment, and fulfilled the Japanese standard. Compared with both types of glulams, solid wood had lower values for modulus of rupture (MOR), modulus of elasticity (MOE), and hardness, but higher shear strength. Meanwhile, polystyrene glulam had lower values for MOR and MOE, equal shear strength and wood failure, and higher hardness than the untreated glulam. All glulams had very little delamination in the hot water test. Only rubber-wood glulams fulfilled JAS 234-2003 for MOR, MOE, shear strength, and delamination. To obtain adequate physical–mechanical properties of glulams, medium-density wood is recommended for glulam manufacturing.

This paper aims to characterize the wood anatomy of Croton piptocalyx. To carry out an investigation of axial variation, discussing it in a functional context, helping to increase knowledge about the species. Five randomly selected 32-year-old trees were felled at the Luiz Antonio Experimental Station, located in Luiz Antonio City, São Paulo state, Brazil. From stems, discs were cut from six different stem heights (stem base, 1 m, 2 m, 3 m, 4 m, and 5 m). For each disc, samples close to the bark were removed for wood anatomy studies and specific gravity calculation. Wood anatomy of C. piptocalyx generally agrees with that of other species of the genus as described in the literature. However, variation in both quantitative and qualitative data could be related to tree age and species differences. Axial variations found in vessel element length, vessel diameter and ray height can be respectively related to the hypothesized Typical Radial Pattern based on the occurrence of shorter and narrower cells in younger parts of the wood, involving vessel element length and diameter, and mechanical requirement in the case of higher rays at the trunk base.Nosso objetivo foi caracterizar anatomicamente a madeira de Croton piptocalyx, investigando a variação axial e discutindo-a em um contexto funcional, contribuindo para aumentar o conhecimento sobre a espécie. Cortamos aleatoriamente cinco árvores com 32 anos de idade na Estação Experimental de Luiz Antonio, na cidade de Luiz Antonio, São Paulo, Brasil. Dos troncos retiramos discos em seis alturas diferentes (base do tronco, 1 m, 2 m, 3 m, 4 m e 5 m). Em cada um dos discos, retiramos amostras próximas à casca para estudos anatômicos e determinação da densidade aparente. A anatomia da madeira de C. piptocalyx em geral é similar com o que já está descrito na literatura para outras espécies do gênero. No entanto, há variações quantitativas e qualitativas, que em parte podem estar relacionadas às diferenças na idade de árvores e, obviamente, à diferença entre espécies. As variações axiais no comprimento dos elementos de vaso, diâmetro do vaso e altura do raio, devem estar relacionadas, respectivamente, ao Típico Padrão Radial, caracterizado pela ocorrência de células menores e mais estreitas em partes mais jovens da madeira (comprimento do elemento de vaso e diâmetro do vaso) e aos requerimentos mecânicos, no caso dos raios mais altos na base do tronco.

The main objective of this research was to investigate tropical wood sorptive properties. For selected tropical wood species (courbaril, ipe, light red meranti, merbau, tatajuba, and teak), the equilibrium moisture content was determined at 20 °C and 9, 30, 55, 70, and 97% relative humidity. The experimentally determined values were analysed using the Hailwood-Horrobin sorption model to compute the fibre saturation point and mono- and multi-layer sorption. There were significant differences in the sorption behaviour of different wood species. Generally, the fibre saturation point of tropical wood species is lower than in wood species from moderate climate zones. The lowest values of fibre saturation point were found for ipe (18.7%), courbaril (20.4%), and tatajuba (20.5%). Furthermore, chloroform-ethanol extractives content was correlated with multilayer sorption and the fibre saturation point, such that a higher content of chloroform-ethanol extractives was associated with a lower equilibrium moisture content. Therefore, chemisorption was not influenced by chloroform-ethanol extractives. Ethanol extracts showed an influence on monomolecular-bound water.

ABSTRACT The lack of use of the residues generated by the mechanical processing of wood and their inadequate disposal are challenges for the timber industry. They have potential for products with higher value. The purpose of this research was to evaluate the use of residues generated by the mechanical processing of Amazonian woods Caryocar villosum, Hymenolobium excelsum, Mezilaurus lindaviana, Erisma uncinatum, Tachigali myrmecophyla and Qualea paraensis in the high-density particleboard production. The panels produced had nominal density of 850 kg.m-3, nominal thickness of 15.7 mm and 8% of phenol formaldehyde adhesive. The physical-mechanical properties of the panels produced from each species and with a mixture of all of them in equal parts were evaluated. The specimens from the panels were prepared for physical tests (apparent density, moisture content, water absorption and thickness swelling) and mechanical tests (static bending - modulus of elasticity and modulus of rupture, and internal bond) according to the standard ABNT NBR 14810-3. The mechanical properties of the particleboards manufactured with the C. villosum, H. excelsum and T. myrmecophyla residues were generally superior than those of the other species and met one or more of the minimum requirements indicated by the ANSI A208.1 standard for (H-1 classification) and for floors production (PBU classification).

Ground contact speeds up timber decay because of the large number of microorganisms in soil. This study, we assessed the natural durability of seven tropical species using the European standard EN 807 (2001). We embedded samples of Dalbergia granadillo, Cordia elaeagnoides, Swietenia humillis, Tabebuia donell-smithii, Hura polyandra, Enterolobium cyclocarpum and Tabebuia rosea and temperate species Fagus sylvatica (as a control) in sandy, clay-sandy-loam and clay-loam for 8, 16, 24 and 32 weeks. We evaluated durability of the samples by determining the mass loss and modulus of elasticity (MOE) loss. The results varied significantly (p < 0.001) depending on timber species and soil type considered. The D. granadillo and C. elaeagnoides were the most durable, with mass losses of 4.5%, 6.5% and MOE losses of 4.5%, 20.5%, respectively. F. sylvatica, T. rosea and E. cyclocarpum samples were the least durable, with mass losses of 22.3-25% and MOE losses of 35.8-59.8%, respectively. Decay was most aggressive in sandy-clay-loam soil followed by the clay-loam soil and finally the sandy soil.

ABSTRACT The objective of this study was to evaluate the volumetric lumber yield of four native species of the Amazon Region: Cedrinho (Erisma uncinatum Warm), Cumaru ( Dipteryx odorata Aublet), Garapeira (Apuleia leiocarpa Voguel), and Cambará (Qualea paraensis Ducke). Twelve logs of each species with different diameters were randomly selected from different sawmills in northern Mato Grosso state, Brazil. Additionally, the influence of diameter on the yield of each species was evaluated through regression analysis. Among the evaluated species, Cedrinho obtained the highest yield values, followed by Garapeira. Cumaru and Cambará showed the lowest yields, and did not differ statistically. Log diameter negatively influenced lumber yield, except for Cumaru wood, which did not present a clear relation between these parameters.

For selected tropical woods (Cumaru, Garapa, Ipe, Kempas, Merbau), a relationship was established between non-isothermal thermogravimetry runs and the wood weight loss under flame during cone calorimetry flammability testing. A correlation was found for the rate constants for decomposition of wood in air at 250 and 300 °C found from thermogravimetry and the total time of sample burning related to the initial mass. Non-isothermal thermogravimetry runs were assumed to be composed from 3 theoretical runs such as decomposition of wood into volatiles itself, oxidation of carbon residue, and the formation of ash. A fitting equation of three processes was proposed and the resulting theoretical lines match experimental lines.

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present work studies the morphological, physical, mechanical and chemical properties, decay resistance, preservation and workability of Cedrela odorata wood from trees growing in agroforestry systems with Theobroma cacao at four ages (4-, 5-, 6- and 7-years-old) in Costa Rica. It was found that the morphological properties (heartwood, pith and bark), together with the physical properties (specific gravity, green density, shrinkage and green moisture content) presented few differences at the four ages. The wood from 4-years-old trees was the only exception, showing less resistance in compression, flexion and lateral hardness. The content of lignin, carbon, and extractives in hot water were not affected among the different ages, contrary to the rest of chemical properties. In relation to decay resistance in accelerated tests with the fungus Trametes versicolor, the wood is classified as highly resistant, while with the fungus Lencites acuta it is classified as moderately resistant. As concerns properties related to industrialization, it was found that the wood can be preserved through vacuum-pressure methods obtaining similar results as those from other plantation timbers. As for workability tests, the wood from the 4-years-old trees show acceptable to very poor performance, differing from trees from the other ages. [ABSTRACT FROM AUTHOR]

Ground contact speeds up timber decay because of the large number of microorganisms in soil. This study, we assessed the natural durability of seven tropical species using the European standard EN-807 (2001). We embedded samples of Dalbergia granadillo, Cordia elaeagnoides, Swietenia humillis, Tabebuia donell-smithii, Hura polyandra, Enterolobium cyclocarpum and Tabebuia rosea and temperate species Fagus sylvatica (as a control) in sandy, clay-sandy-loam and clay-loam for 8, 16, 24 and 32 weeks. We evaluated durability of the samples by determining the mass loss and modulus of elasticity (MOE) loss. The results varied significantly (p < 0,001) depending on timber species and soil type considered. The D. granadillo and C. elaeagnoides were the most durable, with mass losses of 4,5%; 6,5% and MOE losses of 4,5%; 20,5%; respectively. F. sylvatica, T. rosea and E. cyclocarpum samples were the least durable, with mass losses of 22,3-25% and MOE losses of 35,8-59,8% respectively. Decay was most aggressive in sandy-clay-loam soil followed by the clay-loam soil and finally the sandy soil. [ABSTRACT FROM AUTHOR]

The aim of this research was to determine the influence of exposure time at 60 °C in the compression strength parallel to the grain (fc0) and modulus of elasticity in compression parallel to the grain (Ec0) for cupiúba (Goupia glabra), eucalypt (Eucalyptus saligna), garapeira (Apuleia leiocarpa) and jatobá tamarindo (Hymeneae sp.) wood species. The factor investigated in this research was the residence time in kiln (exposure at controlled temperature 60 °C) of specimens: 0 (wood tested at room temperature and moisture content around to 12%), 168, 456, 720, and 2160 hours, simulating the reaction of the material in confined roof structures. Compression parallel to the grain tests were conducted according to the methods of the Brazilian Standard Code ABNT NBR 7190 (1997). ANOVA results indicated that the temperature (60 °C) had a significant influence in the five exposure times. All studied wood species showed an increase in the fc0 value with increasing time of exposure at 60 °C. For Ec0, this phenomenon occurred only for the jatobá tamarindo and cupiúba wood species. [ABSTRACT FROM AUTHOR]

Studies on root wood anatomy are scarce, mainly due to the lack of commercial interest and the difficulty to collect. In Brazilian Cerrado, local craftsmen use root wood for marquetry, the manufacture of such small items as lampshades or ornaments, and table bases. However, taxonomy based on root wood can serve as a guide toward the conservation and management of tree stocks in urban environment. Therefore, we herein describe the root wood anatomy of 14 tree species that occur in the Brazilian Cerrado. To accomplish this, we studied samples from main sinker root, at a depth of about 20 cm, from 37 trees aged 5 to 10 years. Anatomical procedures followed the standard techniques for preparation and analyses of wood samples. We used stem or branch samples from other studies to carry out anatomical description and comparison. However, we encountered some problems, such as: difficulty to distinguish growth rings, sample processing and, in some cases, sample description, since quantity, distribution and type of axial parenchyma differed substantially from that of the main stem. Nonetheless, we did find a variation in the presence/absence of septate fibers among the samples, and noted differences in ray composition. [ABSTRACT FROM AUTHOR]

The work aimed to evaluated the effect of heat treatment on physical and mechanical properties of Hymenolobium petraeum Ducke wood. For this, were manufactured samples with 25.0 × 9.0 × 1.7 cm which were submitted to different heat treatments, with two temperatures (180 and 200 °C) and two exposure times (2 and 4 hours), besides the control samples (without the heat treatment). After the treatments, each sample were submitted to the assays with withdrawal of subsamples for the physical (density, mass loss, equilibrium moisture content and dimensional stability) and mechanical properties (static bending and compression parallel to grain). The heat treatment provided a weight loss of wood, with the higher temperature treatments displayed the greatest losses. However, it proved effective to decrease the equilibrium moisture content and the dimensional stability. The mechanical properties were not affected to the heat treatment. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Environmental conditions affect the natural weathering that leads to changes in wood characteristics. This study was conducted to evaluate physical and color changes and to predict changes in the mechanical properties of uncoated wood after outdoor exposure for 10 months (300 days). Five commercially important tropical wood species from Indonesia were used in field tests in this study, namely sengon or albizia (Paraserianthes falcataria), meranti or shorea (Shorea spp.), mahoni or mahagony (Swietenia spp.), teak (Tectona grandis), and merbau (Intsia spp.). Moisture content, wood density, and color change, as well as the ultrasonic wave velocity and dynamic modulus of elasticity, were evaluated every month. After 2 months of exposure (60 days), color totally changed (ΔE* > 12) for all species except merbau, which underwent changes in the fourth month (120 days). Wood became darker during the experimental period, with the exception of merbau wood, which became lighter by the end of 10 months. Shorea and teak were sensitive to color change as a function of the length of exposure. The wood species and length of exposure also significantly affected both ultrasonic wave velocity and dynamic modulus of elasticity. [ABSTRACT FROM AUTHOR]

This study aimed to verify the behavior of wood Angelim stone (Hymenolobium petraeum Ducke) submitted to the machining process. The study was developed in a carpentry shop in the city of Alta Floresta-MT. 36 boards with dimensions of 150 cm x 13.5 cm x 2.5 cm, length, width and thickness were randomly selected respectively for machining tests. The tests were developed according to the machinability of equipment used by the furniture industry, planing, sanding, drill and split by nail. 8 boards of wood in the stack were selected randomly to determine the moisture, according to 7190 (ABNT, 1997). The notes used for evaluation of defects resulting in the wood during the machining processes were assigned according to ASTM D 1666 (1987). It was observed that the type of angelim stone showed excellent performance in grinding tests, no scratch on the surface piece a of the burring parts and the parts free from defects, with the burning of wood. In cracking test for nail had a good performance, because it showed cracks with the insertion of the nail and planing test a regular performance, with pullout grain, surface arrepiamento and pullout chip. Wood Angelim stone responds with quality to the machining processes in planing, sanding, drill and split by nail.

The purpose of the study was to determine the influence of artificial weathering on selected properties of wood. This paper presents the changes of incompressive strength of wood along fi bers. The study involved wood of different density and anatomy - 17 species of tropical wood commercially available in Europe and Scots pine and European oak. The specimens were exposed to artificial weathering consisting of soaking wood in water, drying at 70 °C and exposure to UV radiation. Three-step aging cycle was repeated 140 times. In general, the tested wood species changed their compressive strength differently under the influence of artificial weathering. The process of artificial weathering caused a loss of strength of all tested wood species. The extent of changes depended on initial properties of wood (especially density) and anatomy. The changes were most pronounced at the beginning of the artificial weathering process.

ABSTRACT The aim of this research was to evaluate the effects of removing fines on the physical and mechanical properties of high-density particleboard produced by mechanical processing of Caryocar villosum (pequiá), Tachigali myrmecophyla (tachi-preto) and Hymenolobium excelsum (angelim-da-mata) Amazonian woods. The panels were produced with nominal density of 850 kg.m-3, thickness of 15.7 mm and phenol formaldehyde adhesive. The experimental design was arranged in a factorial design, with the assessment of the effects of three species (pequiá, tachi-preto and angelim-da-mata) and two particle classifications (with and without fines). Their performance was evaluated with respect to their physical (apparent density, moisture content, water absorption and thickness swelling) and mechanical (static bending – modulus of elasticity and modulus of rupture and internal bond) properties, realized according to ABNT NBR 14810-3. The removal of fines in the production of panels generated a tendency towards increased MoR, MoE and internal bond values and contributed to reductions in AAw2h, AAw24h and ST2h.

Timber from the second cutting cycle may make up the majority of future crop volumetric. However, there are few studies of the physical and mechanical properties of this timber, which are important to support the consolidation of new species. This study aimed to use Artificial Neural Networks to estimate the physical and mechanical properties of wood from the Amazon, based on basic density. The properties were: shrinkage (tangential, radial and volumetric), static bending, parallel and perpendicular to the fiber compression, parallel and transverse to the fibers, Janka hardness, traction, splitting and shear. The estimate followed the tendency of the data observed for the tangential, radial and volumetric shrinkage. The network estimated the mechanical properties with significant accuracy. Distribution of errors, static bending, parallel compression and perpendicular to the fiber compression also showed significant accuracy. Artificial Neural Networks can be used to estimate the physical and mechanical properties of wood from Amazon species.