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Determining the wood properties is fundamental because these properties are directly related to wood quality. The near-infrared (NIR) spectroscopy technique has been used to determine various properties of wood. However, even with promising results, NIR spectroscopy needs to be further investigated to evaluate the robustness of its estimates. The objective of this study was to develop regression models from NIR spectra to estimate the basic density and the extractive and lignin contents of wood as well as to verify their robustness through independent and cross-validation. NIR spectra were initially obtained through an integration sphere and optical fiber for the transverse and radial faces of solid wood and through an integration sphere for powdered wood. The wood basic density and the extractive and lignin contents were determined by conventional methods in 180 and 143 specimens, respectively. The samples were collected from Eucalyptus urophylla × Eucalyptus grandis clones aged 5 years. The basic density and extractive and lignin content values were correlated with the NIR spectra by a partial least squares regression. The best models for estimating the basic density of the wood were generated from the spectra obtained on the transverse surface, both with the integration sphere pathway and in the optical fiber pathway. For estimating the chemical properties of wood, the best models were developed from the powdered wood via the integration sphere for assessing the extractive content, Klason lignin, acid-soluble lignin content and total lignin. In all the models, the mathematical treatment of the data by the first derivative was essential for better fitting the models and reducing the error. We concluded that NIR spectroscopy was effective for the estimation of basic density and extractive and lignin contents of wood. [ABSTRACT FROM AUTHOR]

The collapse-prone nature of eucalyptus wood has implications for the measurement of drying rheological characteristics, particularly free shrinkage. The study outlined the calculation method for drying strain and the determination of drying stress direction. It also analyzed the free shrinkage properties of the wood, as well as the variations in elastic strain, viscoelastic strain, and mechano-sorptive creep strain throughout the drying process. The findings indicate the following: 1, there were no significant differences in free tangential shrinkage between the layers of the specimens. 2, the free tangential shrinkage of the layers was greater than that of the specimens. 3, the use of fresh thin wood that has not been subjected to drying stresses was recommended for accurate measurement of free shrinkage strains, as steaming does not fully reverse the plasticizing deformation caused by drying. 4, the collapse of eucalyptus wood in the early stages of drying hindered the reversal of tensile strain in elastic, viscoelastic, and mechano-sorptive behaviors. [ABSTRACT FROM AUTHOR]

The demand for forest-related goods and services has continued to grow in Ethiopia due to the increasing population, urbanization, and the boom of the construction sector. In the past, the demand was covered by indigenous timber species, which now have declined due to unwise exploitations. To narrow down the gap between supply and demand an alternative solution is promoting and utilizing fast-growing species such as Eucalyptus wood. To effectively utilize this species identifying its special characteristics, level of acceptance in wood industries, and utilization practices are very important. To achieve the goals of this review, a thorough search was carried out across multiple scholarly databases. Then, pertinent research, papers, and articles about the use of Eucalyptus in the wood industries were downloaded and reviewed. The study shows that Eucalyptus is widely cultivated in various regions of Ethiopia and plays a significant role in the socio-economic dimensions of many Ethiopians, providing livelihood opportunities, environmental services, and supporting sustainable development. Although it is being used as an alternative to traditional timber species in many places in the world, it is not being widely used in Ethiopia's wood industry for furniture manufacturing. This is because producers are unaware of the special properties of this species; its felling technique, sawing method, and drying behavior which demands proper attention and care. To ensure the sustainable use of Eucalyptus resources, better tree management techniques, innovative wood processing techniques, market development, and strengthening the capacity of relevant stakeholders are imperative.

Eucalyptus plantations are an important source of raw materials for the Thai forest products industry. Despite its economic value, only a few noncomprehensive papers have been published about the wood properties and fungal susceptibility of eucalyptus. Our study covered the most commonly used commercial eucalyptus clones with a wide variety of sizes from eastern Thailand. We assumed that the properties of the clones would differ based on the tree sizes. The objectives of this study were to determine the effects of diameter at breast height (DBH), size, and clone type on wood properties and mould susceptibility. The optimal usage of each log characteristic based on the log quality and properties could be used to determine the maximum payoff. The wood properties and log characteristics of five eucalyptus log classes with three clones were investigated. In general, the levels of means and standard deviations were as follows: the modulus of rupture (MOR) was between 39 ± 4.9 MPa and 66 ± 5.4 MPa, and the modulus of elasticity (MOE) was between 14.5 ± 9.7 GPa and 24.0 ± 2.7 GPa. In addition, the compression parallel to the grain was between 28 ± 3.2 MPa and 43 ± 2.4 MPa, and the compression perpendicular to the grain was between 13 ± 0.7 MPa and 19 ± 1.1 MPa. The shear strength parallel to the grain was between 10 ± 0.3 MPa and 14 ± 0.6 MPa. The cleavage and hardness were from 4.7 ± 1.6 N to 7.4 ± 0.9 N and from 3.6 ± 0.3 kN to 6.2 ± 0.6 kN, respectively. The toughness and nail withdrawal were from 27.3 ± 3.5 kN.mm-1 to 50.5 ± 1.0 kN.mm-1 and from 28.56 ± 4.1 N.mm-1 to 34.52 ± 2.8 N.mm-1, respectively. Eucalyptus clone K7 had lower MOR and other mechanical properties than clones K58 and K62 except MOE. When DBH increased, the mechanical and physical property values increased as well. This happened for all clones, and especially when DBH was over 200 mm. The results of this study showed that log characteristics, such as taper, slenderness, and crookedness, should be used for log grading standards and that each fast-growing eucalyptus clone could be applied to different product classes.

Eucalyptus plantations are an important source of raw materials for the Thai forest products industry. Despite its economic value, only a few noncomprehensive papers have been published about the wood properties and fungal susceptibility of eucalyptus. Our study covered the most commonly used commercial eucalyptus clones with a wide variety of sizes from eastern Thailand. We assumed that the properties of the clones would differ based on the tree sizes. The objectives of this study were to determine the effects of diameter at breast height (DBH), size, and clone type on wood properties and mould susceptibility. The optimal usage of each log characteristic based on the log quality and properties could be used to determine the maximum payoff. The wood properties and log characteristics of five eucalyptus log classes with three clones were investigated. In general, the levels of means and standard deviations were as follows: the modulus of rupture (MOR) was between 39 ± 4.9 MPa and 66 ± 5.4 MPa, and the modulus of elasticity (MOE) was between 14.5 ± 9.7 GPa and 24.0 ± 2.7 GPa. In addition, the compression parallel to the grain was between 28 ± 3.2 MPa and 43 ± 2.4 MPa, and the compression perpendicular to the grain was between 13 ± 0.7 MPa and 19 ± 1.1 MPa. The shear strength parallel to the grain was between 10 ± 0.3 MPa and 14 ± 0.6 MPa. The cleavage and hardness were from 4.7 ± 1.6 N to 7.4 ± 0.9 N and from 3.6 ± 0.3 kN to 6.2 ± 0.6 kN, respectively. The toughness and nail withdrawal were from 27.3 ± 3.5 kN·mm-1 to 50.5 ± 1.0 kN·mm-1 and from 28.56 ± 4.1 N·mm-1 to 34.52 ± 2.8 N·mm-1, respectively. Eucalyptus clone K7 had lower MOR and other mechanical properties than clones K58 and K62 except MOE. When DBH increased, the mechanical and physical property values increased as well. This happened for all clones, and especially when DBH was over 200 mm. The results of this study showed that log characteristics, such as taper, slenderness, and crookedness, should be used for log grading standards and that each fast-growing eucalyptus clone could be applied to different product classes. [ABSTRACT FROM AUTHOR]

The influence of pulping variables on the pulp and black liquor properties for a neutral sulphite semi-chemical pulping system was investigated in a pilot plant pulping setup situated at an industrial paper mill. Eucalyptus chips were used as raw material and the operating variables were Na2SO3 charge (8–18% w/w on oven-dry wood), Na2CO3 charge (0.5–3.0% w/w on oven-dry wood) and maximum cooking temperature (160–180 °C). Response surface methodology was used to parametrize empirical models to find the optimal conditions for maximizing the short-span compression strength index of the pulp. The derived regression models for the black liquor properties and the pulp hypo number had R2-adjusted values above 0.8 and p-values for overall significance below 0.05. The derived regression models for the handsheet strength properties had R2-adjusted values between 0.3 and 0.45 and p-values for overall significance either below 0.05 or between 0.05 and 0.1. The sulphite charge, followed by the carbonate charge, had the most notable effect on the evaluated properties with the effects of temperature being less significant. Optimization of the pilot plant system showed that the short-span compression strength index of the pulp could be maximized to 26.7 N m/g, using a sulphite charge of 9.4% (w/w on oven-dry wood) and a carbonate charge of 1.94% (w/w on oven-dry wood), similar to short-span compression strength indices typically achieved using other pulping processes. [ABSTRACT FROM AUTHOR]

A rectangular waveguide antenna was tested for eucalyptus wood moisture content (MC) measurement before being used. To improve the moisture content measurement of the rectangular waveguide antenna, a woodpile-shaped Electromagnetic Band Gap (EBG) was installed by Transverse Electric (TE) arrangement. This antenna is responsible for receiving and transmitting signals which are converted from electrical energy into radio frequency energy transmitted through the air. In this research, we take advantage of the wave propagation of antennas in the air and use them to propagate waves through wood materials. To compare signal transmission power to determine moisture content in wood and the benefit of the EBG is that it acts like a convex lens to increase the strength of the waves so that they can penetrate the wood more efficiently. The results showed that woodpile-shaped EBG could increase the efficiency of receiving and transmitting signals, reduce working hours for farmers and reduce costs by about 90 %. When this antenna was tested and actually used, it was found that the frequency band that responded best to the moisture content value was 2.20 GHz. This antenna was built with an aluminum material of size 9×4×15 cm3 and 2×6 units woodpile EBG on a 9.54×4 cm2 Polyester Mylar base plate. There was a gain of 7.81 dBi from the original structure, or by 20 %. At a radius of 4 cm, the values of moisture content ranged from -9.46 to -42.19 dBm. At a radius of 6 cm, the values were -9.41 to -42.89 dBm. At a radius of 8 cm, the values ranged from -9.39 to -43.01 dBm, respectively. All 3 values were found to be efficient. The size was not less than 84 % compared to the general standard meter. [ABSTRACT FROM AUTHOR]

Energy issues are becoming increasingly prominent, and biomass blending in coal-fired power plants can improve combustion performance and reduce gaseous pollutant emissions, thereby improving economic efficiency. In this study, a thermogravimetric analyzer, a horizontal tube furnace, and an infrared flue gas analyzer were used to investigate the combustion behavior and gaseous pollutant emissions of the co-combustion of LC and EW. The results show that blending EW into LC cofiring can inhibit the release of volatile matter and promote the decomposition of fixed carbon and lignin simultaneously. The HHV of EW (15.88 MJ/kg) reaches 63.7% of LC’s (24.90 MJ/kg), indicating EW has a high energy utilization value. With increasing combustion temperature, the average value of CRS increased from 47.09% to 59.94%, and the average value of CRCl increased from 26.15% to 52.15%, leading to a significant increase in SO2 and HCl emissions. The decrease in combustion temperature slightly promoted the release of N (CRN increased from 11.76% to 14.45%). The results of the economic analysis show that the cost of CaO and NH3·H2O used for removing gaseous pollutants decreased the most, and the economic efficiency increased the fastest to 14,000 RMB/day when the EW blending ratio increased from 10% to 20%. [ABSTRACT FROM AUTHOR]

Eucalyptus wood vinegar (WV) is a versatile natural product employed in several areas such as for agriculture, zootechnics, and veterinary applications. However, the product may contain contaminants such as polycyclic aromatic hydrocarbons, methanol, metals, and so on in its raw form. Thus, refining is required to remove them. Only after reaching a high-purity grade can WV be applied as a basis for pharmaceuticals, antimicrobials, and additives for animal husbandry. This work aimed to assess the effect of refining on the contaminant content of a WV produced on an industrial scale and traded as agricultural input in the Brazilian market. WV was refined by sequential vacuum distillations and had its contaminant contents assessed before and after refining. The following chemical classes were investigated: metals and other elements, insecticides, fungicides, and herbicides (carbamates, organochlorines, organophosphates, pyrethroids, and others), mycotoxins, polychlorinated dioxins and furans, polycyclic aromatic hydrocarbons, and volatile organic compounds, encompassing more than 100 chemical species. Also, the WV physical–chemical properties before and after refining were determined. Gas chromatography and mass spectrometry (GC/MS) were employed to attain the WV's chemical profile. The main chemical components, such as phenolic compounds, furans, ketones, pyrans, etc., were annotated in the WV chemical profile. No traces of insecticides, fungicides, herbicides, heavy metals, mycotoxins, polychlorinated dioxins, or polychlorinated furans were found in raw WV or refined versions. However, several other undes/irable chemicals were determined in the raw product, such as PAHs and volatile organic compounds (acetaldehyde, acetone, ethylene glycol, and methanol). Nevertheless, all of them were effectively removed from the raw WV after the first or second sequential refining steps, resulting in a pure product. Therefore, only one refining step can be applied to raw WV to yield a high-quality product for pharmaceutical and animal husbandry applications. [ABSTRACT FROM AUTHOR]

β-sitosterol (BS) is a phytosterol with wide potential in cosmeceutical, biomedical and food applications. In acid sulphite pulp cooking, BS and its derivatives are considered an underutilized natural source of bioactive compounds, which are adsorbed on the resulting pulp or dispersed in the spent liquor. In this work, a new method for the isolation of BS from alkaline extract (AE) of unbleached sulphite pulp purification stage is proposed. BS was recovered by two-step acidification of AE up to pH 3 under pre-selected conditions, followed by fractionation of the formed precipitate with water-miscible organic solvents, having obtained best results (>90% of BS purity; yield of 70-210 mg/dm3 of AE) with mefthanol fractionation followed by BS crystallization induced via addition of water (ca. 10% vol.). When ethanol was used instead, BS was detected in low amounts in the isolate, being fatty acid sterol esters and fatty acid glycerides the major components, as revealed from analyses by wet chemistry coupled with gas chromatography-mass spectrometry and thin layer chromatography (TLC). The method is adaptable for large-scale industrial production of BS and may represent an important source of sterol-based products. [ABSTRACT FROM AUTHOR]

Microbial resistance to drugs is a public health problem; therefore, there is a search for alternatives to replace conventional products with natural agents. One of the potential antimicrobial agents is wood vinegar derived from the carbonization of lignocellulosic raw materials. The objectives of the present work were to evaluate the antibacterial and antifungal action of two kinds of wood vinegar (WV), one of Eucalyptus urograndis wood and another of Bambusa vulgaris biomass, and determine their chemical profile. The antimicrobial effect was assessed against Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enteritidis, Escherichia coli, Streptococcus agalactiae, and Candida albicans. The minimum inhibitory concentration and the minimum bactericidal and fungicidal concentrations were determined. Micrographs of the microorganisms before and after exposure to both kinds of wood vinegar were obtained by scanning electron microscopy. The chemical profile of the eucalyptus and bamboo vinegar was carried out by gas chromatography and mass spectrometry (GC/MS). Both types of WV presented significant antimicrobial activity, with the bamboo one having a higher efficiency. Both studied pyroligneous extracts seem promising for developing natural antimicrobials due to their efficiency against pathogens. GC/MS analyses demonstrated that the chemical profiles of both kinds of WV were similar but with some significant differences. The major component of the eucalyptus vinegar was furfural (17.2%), while the bamboo WV was phenol (15.3%). Several compounds in both WVs have proven antimicrobial activity, such as acetic acid, furfural, phenol, cresols, guaiacol, and xylenols. Together, they are the major in the chemical composition of the organic fraction of both WVs. Bamboo vinegar had a more expressive content of organic acids. Micrographs of microorganisms taken after exposure to both kinds of wood vinegar displayed several cell modifications. The potential of both types of wood vinegar as a basis for natural antimicrobial products seems feasible due to their proven effect on inhibiting the microorganisms' growth assessed in this experiment. [ABSTRACT FROM AUTHOR]

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Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office 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.)

Hard carbon is generally considered to be an attractive disordered carbon anodes for Na-ion batteries (NIBs). Herein, a type of Eucalyptus wood-derived hard carbon (HC) material is reported for efficient Na storage, which holds several merits such as high initial Columbic efficiency (89.1%), moderate carbon yield (21%) and satisfying electrochemical performance simultaneously. Natural holey structure inherited from wood lead to hierarchical porous morphology of the resulting HC. The structural and morphological properties have been characterized by XRD, XPS, BET, SEM, TEM and Raman spectroscopy. Small angle X-ray scattering analysis (SAXS) is used to obtain the closed pore information. The optimal HC was got by changing pyrolysis temperature to regulate the open and closed pores. It has a high specific capacity of about 300 mAh g−1 and a good capacity retention of 93% after 200 cycles at 0.1 A g−1 in the range of 2–0.01 V. A considerably high desodiation capacity of 239 mAh g−1 can be delivered even at 5 A g−1. This may provide a rational guide for designing hard carbon anode with comprehensive merits for NIBs. [ABSTRACT FROM AUTHOR]

Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office 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.)

Climate change and the advancement of forestry in areas with greater water scarcity represent major challenges for Eucalyptus cultivation in Brazil. This study aimed to evaluate the productivity and wood quality of non-traditional Corymbia and Eucalyptus species in two Brazilian climatic conditions, to expand the genetic base available for breeding programs. Mean annual increment, wood density, stem biomass, heartwood and bark percentage, tangential vessel diameter, vessel frequency, fiber length, and fiber wall thickness were assessed. Four Corymbia species (Corymbia citriodora subsp. citriodora , Corymbia henryi , Corymbia torelliana , Corymbia citriodora subsp. variegata) and three Eucalyptus species (Eucalyptus amplifolia , Eucalyptus longirostrata , Eucalyptus major) were evaluated. Monthly evaluations were conducted on the mean air temperature, precipitation, and soil water deficit. Soil water deficit had a negative impact on mean annual increment, biomass, and heartwood percentage, while also resulting in higher bark percentages. However, it did not affect wood density or vessel diameter. The species showed different behaviors in response to the increase in water deficit. Eucalyptus longirostrata had the lowest impact on the environment, the highest mean annual increment (48.40 m³ ha−1 and 26.94 m³ ha−1) and heartwood percentage values (19.23 % and 16.27 %). Corymbia henryi had the most similar mean annual increment values in both locations (25.33 m³ ha−1 and 20.18 m³ ha−1), but there was a significant decrease in heartwood formation in the location with the lower soil water deficit (18.20 %). Corymbia citriodora subsp. citriodora , Corymbia henryi , Corymbia citriodora subsp. variegata , Eucalyptus major , and Corymbia torelliana displayed strong growth and wood characteristics, indicating great potential for cultivation in both locations. • Site differences had an impact on tree growth. • Productivity decreases as water deficit increases. • The climate variations across sites didn't impact the species' vessel density or diameter. • C. citriodora subsp. variegata and E. longirostrata had the highest stem biomass values in both sites. [ABSTRACT FROM AUTHOR]

Alkali and alkali earth metals (AAEM) can be removed from lignocellulosic biomass via a new demineralization process constituting hydrothermal treatment. The dissolution mechanism of AAEM in different demineralization processes has not been extensively studied. This study employed calcium as a representative of the AAEM group, and changes in the concentration of calcium ions during the hydrothermal demineralization of eucalyptus wood were studied. The dissolution kinetics were modelled using Fick’s second law. The effects of the reaction temperature, hydrolysate pH, and holding time on the dissolution rate of calcium ions were investigated. The kinetic equation for calcium ion dissolution was expressed as ln(1.9532e0.0077T/1.9532e0.0077T -C) = (0.4257P-0.2142e -10622.1/8.314T )t + ln(1.9532e0.0077T /1.056×10-8T 3.5263p 0.4449). The activation energy of the reaction was 10.62 kJ/mol. The linear regression coefficient (R²) of the predicted and experimental values was 0.9879, which implied high precision of the kinetic model. The results showed that the calcium ions underwent rapid internal diffusion and dissolution during hydrothermal demineralization. The study provides theoretical support for the efficient removal of alkali earth metals via hydrothermal demineralization. [ABSTRACT FROM AUTHOR]

The presence of phenolic compounds in petroleum refinery wastewater is a matter of significant environmental concern. Its removal is achieved through various methods, among which adsorption is an efficient and economically viable option. This study reports the development of activated biochar (EABC) from Eucalyptus wood pyrolytic biochar (EPBC) to remove phenols from petroleum refinery wastewater. The best activation strategy involved ball-milling of KOH and EPBC in the ratio 3:1, followed by annealing at 800 °C under an N2 atmosphere. The activated biochar (EABC-3–800) exhibited high phenol adsorption capacity (308.9 mg/g), attributed to the presence of heterogeneous pores, corroborated by large BET surface area (2048 m2 /g). As determined through HPLC, the EABC-3–800 could remove nearly 95% phenol (C0=114 ppm) from the wastewater of the delayed coking unit of a petroleum refinery. The best-fitting of the adsorption results in the Freundlich isotherm model substantiates the hypothesis of pore-based adsorption of phenol compared to the surface-adsorption-based Langmuir isotherm. The phenol adsorption kinetics followed the pseudo-second-order model, indicating weak chemical interactions between phenol and activated biochar. The regeneration and reuse of EABC-3–800 for a minimum of five operational cycles demonstrate its potential for industrial wastewater remediation.

The wood‐to‐charcoal process (carbonization) is crucial in developing new materials at the lab for key technological processes nowadays. Unfortunately, laboratory carbonization methods are relatively costly and produce charcoal on a one‐gram scale. This work presents a simple‐to‐build and simple‐to‐operate homemade kiln that carbonizes Eucalyptus wood chips (yield of 30±1 %) and produces charcoal on the 200‐gram scale (two orders of magnitude higher). As‐made solid particles had the typical structure, composition, and chemical behavior of charcoal obtained from wood with standard carbonization procedures. Research of charcoal‐based materials is now probably more accessible. [ABSTRACT FROM AUTHOR]

Herein, lignin‐rich KOH‐activated porous carbon from eucalyptus wood (named as PACE) is presented as an efficient electrode for supercapacitors (SCs). Compared with the most commonly used higher activation temperature, i.e., 800 °C with KOH (PACE‐800), a more efficient SC is developed by activating carbon with KOH at lesser temperature, i.e., 600 °C (PACE‐600). The high specific capacitance (i.e., 230 F g−1 at 1 A g−1 measured in a 2 m NaCl electrolyte) measured by galvanostatic charge–discharge (GCD) studies is not primarily due to larger surface area, but due to the inherent electron‐rich oxygen‐based functionalities that persist at the lower activation temperature, contributing to the hydrophilic nature to PACE‐600. The mechanism of the capacitive charge storage is deduced from electrochemical impedance spectroscopy (EIS). The application of PACE‐600 as a SC electrode is confirmed from insignificant loss in the specific capacitance after 10 000 charging–discharging cycles, recorded at 10 A g−1. Further, fabrication of higher‐voltage (1.6 V) symmetric SC PACE‐600//PACE‐600 in aqueous neutral electrolyte (2 m NaCl) is presented, which illuminates a red LED (1.8 V) for 1 min after charging for 5 s. The corresponding energy density is calculated to be 41 W h kg−1, and at a power density of 2396 W kg−1. [ABSTRACT FROM AUTHOR]

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Changes in the lignin structure of eight eucalypt species (E. botryoides, E. globulus, E. grandis, E. maculata, E. propinqua, E. rudis, E. saligna, and E. viminalis) upon mild thermal treatment, where the temperature was gradually raised from 160 to 230 °C over 3 h, were studied by solid-state carbon nuclear magnetic resonance (13C NMR) and after lignin isolation from the wood by acidolysis employing liquid-state 1D and 2D NMR techniques. The molecular weight of the isolated lignins was assessed by size exclusion chromatography (SEC) and their composition by analytic pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS). The thermal treatment induced in lignin partial demethylation (up to ca. 30% from total) and a remarkable reduction in β-O-4 structures (up to ca. 60%), in an extent depending on the ratio of syringyl and guaiacyl units of the specific lignins. The lignin molecular weight reduced only ca. 25% under the thermal treatment due to the likely occurrence of condensation reactions by homolytic and heterolytic mechanisms. The noticeable increase in phenylcoumaran (β-5) and pinoresinol/syringaresinol (β-β) structures in lignin after thermal treatment was tentatively explained by their relative thermal resistance and by newly formed structures as the result of radical coupling reactions occurred during homolytic dissociation of the β-O-4 linkages. Lignins in thermally treated wood contained more than twice phenolic hydroxyls and more aliphatic carboxyl groups than lignins in untreated wood. [ABSTRACT FROM AUTHOR]

Eucalyptus globulus wood samples were subjected to hydrothermal processing according to a three-stage, crossflow scheme with intercalated washing stages. The operational conditions for each hydrothermal stage were selected based on previous experiments, as the kinetics and yields depended on the composition of the reaction media. The solid recovery yields as well as the compositions of the various solids and liquids involved in each stage were measured, in order to allow the formulation of material balances. Under the conditions selected, the various stages enabled solid recovery yields in the range 70.8–74.4 g/100 g oven-dry wood, with extensive hemicellulose removal and almost quantitative recovery of both cellulose and lignin in solid phase. The production of valuable polysaccharide-derived products (including saccharides and furans) along the process decreased owing to the different initial composition of the various reaction media. In turn, the generation of monosaccharides from soluble saccharides of oligomeric or polymeric nature was promoted in the second and third stages. The experimental data provided in this study allow a quantitative assessment on the considered process, a basic information for simulation and economic evaluation. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the influence of sample preparation including variation in moisture content and particle size on the accuracy of near infrared (NIR) spectroscopy models developed to predict Klason lignin, total lignin, and holocellulose in wood. Seventy-five samples of sawdust obtained from a eucalyptus plantation were divided into aliquots and submitted to three different treatments: traditional (TRAD), large particle dried at room temperature (LPRT), and large particle oven-dried (LPOD). The influence of sample preparation method on models' accuracy was compared by statistical analysis. Overall, grinding to a larger particle size and drying at room temperature (treatment LPRT) did not decrease the accuracy of the prediction models when compared to the TRAD sample preparation method. These findings were more evident for Klason lignin and holocellulose. This is relevant because resources used for sample preparation (i.e. grinding and drying) can be minimized, which is expected to reduce the costs associated with analysis of wood properties by NIR. [ABSTRACT FROM AUTHOR]

The objective of this study was to verify the behavior of the sawn wood of eucalyptus clones during the drying process in the open air, in order to subsidize the phenotypic classification for genetic selection, through the evaluation of wood quality. For this, 15 boards of 2.54 x 10.00 x 1.20 cm were used for each drying process in the open air, after the evaluation of the drying defects, in addition, the index from top to bottom cracks. Already for the determination of the linear contraction coefficients, maximum volumetric contraction and anisotropy coefficient, 30 specimens with dimensions 2.0 x 2.0 x 10.0 cm per clone were used. Clone 1007 presented the highest drying rate, being considered the one with the best performance in relation to the appearance of top cracks in log and quality in the incidence of defects after drying, and its genetic selection is recommended. The average of the basic density of the hybrids was 0.4016 g.cm-3, characterizing the wood as light. The species under study have low retractable wood, being within the limits presented in the literature for the genus Eucalyptus, the anisotropic factor indicated that the wood exhibits normal behavior. [ABSTRACT FROM AUTHOR]

As a wood containing many ordered cell cavities and blood vessels, eucalyptus is an ideal precursor material in preparing hierarchical porous carbon electrodes for Zn-air batteries. However, insufficient micro-mesoporous and minor active sites inhibit the application of wood-directly derived carbon materials in Zn-air batteries. Hence, a simple and cost-effective formic acid pretreatment method was proposed to prepare nitrogen-doped bulk phase catalysts with abundant micro-mesoporous and enough high active sites from eucalyptus. Formic acid pretreatment selectively removed part of lignin and hemicelluloses, thus generating abundant nanopores and contributing to the introduction of more nitrogen active sites. Moreover, the obtained bulk carbon had high mechanical strength and wonderful electrical conductivity, containing cross-linked networks and natural ion transport channels. Benefiting from the above advantages, the bulk carbon catalyst could be directly used as self-supported cathode, and the resulting Zn-air batteries achieved a long cycle life of more than 300 h. This work provides a simple and feasible method for the development of biomass-derived hierarchical bulk-phase porous carbons for energy-related applications. • Hierarchical porous nitrogen doped bulk carbon derived from eucalyptus by formic acid pretreatment. • The bulk carbon with a large number of nanopores has high mechanical strength and high electrical conductivity. • A high number density of graphite N and pyridine N is introduced in carbon lead to favorable ORR activity. • The Zn-air battery with bulk FA-CN achieves a long cycle life of more than 300 h at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

The combination of autohydrolysis and ionic liquid microwave treatments of eucalyptus wood have been studied to facilitate sugar production in a subsequent enzymatic hydrolysis step. Three autohydrolysis conditions (150 °C, 175 °C and 200 °C) in combination with two ionic liquid temperatures (80 °C and 120 °C) were compared in terms of chemical composition, enzymatic digestibility and sugar production. Morphology was measured (using SEM) and the biomass surface was visualized with confocal fluorescence microscopy. The synergistic cooperation of both treatments was demonstrated, enhancing cellulose accessibility. At intermediate autohydrolysis conditions (175 °C) and low ionic liquid temperature (80 °C), a glucan digestibility of 84.4% was obtained. Using SEM micrographs, fractal dimension (as a measure of biomass complexity) and lacunarity (as a measure of homogeneity) were calculated before and after pretreatment. High fractals dimensions and low lacunarities correspond to morphologically complex and homogeneous samples, that are better digested by enzyme cocktails. [ABSTRACT FROM AUTHOR]

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The potential for using pectinase as a pre-treatment to improve the properties of bamboo or eucalyptus fibers for use in a woody fiber/polypropylene (PP) composite was compared with the addition of a silane coupling agent or NaOH pre-treatment. Pectinase pre-treatment reduced the amount of pectin in both fibers (p < 0.0001) and this reduction was associated with improved tensile strength, modulus of rupture and modulus of elasticity (p < 0.001) of bamboo, or eucalyptus fiber-based composites. Pre-treatment had no consistent effects on the thickness swell or water absorption. The addition of a coupling agent produced similar improvements in panel properties (p < 0.05), but also markedly reduced moisture absorption and thickness swell (p < 0.05). Sodium hydroxide pre-treatment had no consistent effects on panel properties, although it did appear to affect thickness swell. Short pectinase pre-treatment might be useful for enhancing the properties of woody tissue/PP composites while reducing but not completely eliminating the need for coupling agents. [ABSTRACT FROM AUTHOR]

In analytical pyrolysis, carbohydrates are degraded into stable anhydrosugars, which are analyzed by GC/MS. The benefit of Py-GC/MS is that fiber composition including carbohydrates, lignin and its S/G ratio can be determined simultaneously from fiber-based materials without need of extensive pretreatment, contrary to the traditional method. In this study, the relative carbohydrate composition of various Eucalyptus species was determined by Py-GC/MS. In addition, pulps produced from the same species by soda-AQ and soda-O 2 processes were analyzed similarly. The results were compared with those obtained by acid hydrolysis followed by HPLC. This comparison showed that the relative carbohydrate composition determined by Py-GC/MS for the wood samples differed from the values obtained by acid hydrolysis. Significantly better correlation between the two methods was observed for the pulp samples cooked to varying kappa number levels. Fractionated pyrolysis was applied in order to find explanation to the observed difference in the degradation behavior of carbohydrates in wood and pulp samples. Due to the close association of lignin and carbohydrates, the thermal behavior of lignin was followed as well. The results showed that the thermal behavior of xylan and cellulose differed in the wood samples, but were almost equal in the pulp samples. Thermal degradation of xylan was similar with lignin in both sample types. Similar thermal behavior between the components is a prerequisite for reliable Py-GC/MS analysis. Therefore, this method cannot be recommended for the comparison of carbohydrate compositions between different wood raw materials. However, it is applicable to pulp samples and may find application in research for profiling carbohydrate compositional changes with processing methods: and conditions. [ABSTRACT FROM AUTHOR]

Chemical pulp was prepared by the low-temperature, atmospheric pressure, and short reaction time pulping of Eucalyptus wood chips using a high-boiling-point solvent. The pulping conditions and pulp properties were evaluated. After the digestion of the Eucalyptus chips, pulp containing 6% residual lignin was obtained in 59.6% yield. It exhibited a low shive content and a sufficiently pulped appearance. With subsequent digestion at 110 °C for 60 min, the shive content further decreased, and fiber bundles disintegrated by simple mechanical stirring. The fiber length and width of the pulp were 500-577 and 20.1-27.9 μm, respectively, and the fiber roughness was 8.8-16.8 mg/100 m. The degree of crystallization of the pulp proportionally increased with cooking temperature. The brightness of the pulp with ~ 6% residual lignin content was greater than 52% ISO, and the zero-span tensile strength and viscosity gradually increased with pulping time. [ABSTRACT FROM AUTHOR]

Effects of different acid hydrolysis conditions were studied relative to the chemical transformations of lignin in eucalyptus, sugarcane bagasse, and sugarcane straw, and on the transformations of multiple polysaccharides in eucalyptus. The acid hydrolysis using 12 mol/L sulfuric acid followed by acid hydrolysis using approximately 0.41 mol/L sulfuric acid was used as the reference for the lignin and sugar analysis. During acid hydrolysis, the relative amount of lignin increased with longer reaction times and/or greater acid concentrations for all biomasses. The overestimation of lignin in harsher acidic conditions resulted from the summation of lignocellulosicderivatives (pseudo-lignin) together with lignin itself. Lignin reactions (dissolution/deposition) for bagasse and straw occurred in a greater extent than for eucalyptus, considering similar conditions of acid hydrolysis. The sugar transformation during acid hydrolysis was also investigated for eucalyptus. The sugar content quantified in eucalyptus decreased as the acid concentration and/or reaction time in the second hydrolysis increased. Glucose, galactose, and mannose were more resistant to harsher acidic conditions than xylose and arabinose. However, the most severe conditions (121 °C, 90 min, and 6.15 mol/L H2SO4) caused complete sugar degradation. [ABSTRACT FROM AUTHOR]

Hydrothermal and acid pretreatments using different acid charges (1.5%, 3.0%, and 4.5% H2SO4) were proposed for eucalyptus, sugarcane bagasse, and sugarcane straw prior to their bioconversion into ethanol using the semi-simultaneous saccharification and fermentation (SSSF) process. The hydrothermal and acid pretreatments were efficient for hemicelluloses removal from eucalyptus (63 to 96%), bagasse (25 to 98%), and straw (23 to 95%) and to remove a substantial amount of lignin from eucalyptus (10 to 34%) and bagasse (10 to 27%). During pretreatments, pseudo-extractives and pseudo-lignin were generated from biomasses. The SSSF was performed in pretreated biomasses using 24 h presaccharification followed by an additional 10 h of simultaneous saccharification and fermentation (SSF). With hydrothermal pretreatment, the eucalyptus presented the highest ethanol production, but only low values for SSSF parameters were obtained, as follows: ethanol yield (0.017 gethanol/gbiomass), volumetric productivity of ethanol (0.16 g L-1 h-1), and ethanol concentration (1.6 g L-1). On the other hand, using acid pretreatment, the straw (pretreated using 4.5% H2SO4) presented the highest ethanol production among the biomasses, assessed based on ethanol yield (0.056 gethanol/gbiomass), volumetric productivity of ethanol (0.51 g L-1 h-1), and ethanol concentration (5.1 g L-1). [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG) 2000/phosphate salt based aqueous two-phase systems (ATPS) were used to recover phenolic compounds with antioxidant activity from wastes of eucalyptus wood veneers. Combinations of two phosphate salts (KHPO or mixtures of KHPO and KHPO) with PEG 2000 were studied in order to understand the influence of pH and type of salt on phenols partition. Each ATPS was studied under different conditions (polymer/salt ratio, temperature, volume ratio and solid-liquid ratio). In all the ATPS studied, it was found that phenols had preference for the PEG-rich phase and it was demonstrated that the highest phenols recovery was favored by a high polymer/salt ratio, high temperature and a high volume ratio. The maximum total phenols yield in the top phase, 1.89 mg gallic acid equivalent/100 mg oven dried wood, was attained at 65 °C and a solid/liquid ratio of 0.5:10 using a PEG 2000/KHPO ATPS. However, higher partition coefficients were attained for PEG 2000/KHPO-KHPO ATPS. It was found that at low pH values higher partition of phenolic compounds was achieved. Extract analysis by RP-HPLC-ESI-TOF confirmed the presence of various phenolics compounds with antioxidant activity such as ellagic acid and quercetin 3- O-rhamnoside. [ABSTRACT FROM AUTHOR]

Este trabalho teve como objetivo geral analisar a competitividade da cadeia produtiva da madeira de eucalipto no Brasil, comparando diferentes sistemas de produção, por meio da matriz de análise política (MAP). Pelos resultados, conclui-se que a lucratividade privada e social da produção e comercialização da madeira de eucalipto foi positiva e maior em áreas motomecanizáveis; os produtores brasileiros foram penalizados por políticas públicas adotadas para o setor; a produção em áreas motomecanizáveis apresentou-se mais competitiva e menos exposta aos efeitos negativos das políticas públicas; e os produtores nacionais tiveram seus lucros reduzidos.The present work aimed to analyze the competitiveness of the eucalyptus productive chain in Brazil, comparing different production systems, through a policy analysis matrix (PAM). Based on the results obtained, it was concluded that the private and social profitability of the production and commercialization of eucalyptus was positive and greater in flat areas; Brazilian producers were penalized by the public policies adopted for the sector; the production in flat areas was more competitive and less exposed to the negative effects of public policies; and national producers had decreased profits.

Este trabalho analisou a percepção dos fabricantes do Polo Moveleiro de Ubá, MG, quanto à utilização da madeira de eucalipto para a fabricação de móveis. A crescente restrição ambiental ao uso de madeiras provenientes de florestas nativas tem estimulado a utilização da madeira de reflorestamento, principalmente a de eucalipto. Foram entrevistadas 17 empresas do segmento de sala de jantar, 21 do segmento de cama e 6 do segmento de móveis sob encomenda. A experiência de uso da madeira de eucalipto foi constatada em 43,2% das empresas, sendo os principais fatores que influenciaram seu uso: o fato de a madeira ser proveniente de floresta plantada e ter características uniformes, além da escassez de madeira oriunda de florestas nativas. Das empresas que nunca usaram a madeira de eucalipto, 88% já ouviram falar das suas potencialidades, mas não usavam porque tinham pouco conhecimento sobre o assunto, faltavam fornecedores, não havia demanda por parte dos consumidores e consideravam alto o preço dessa madeira. Conclui-se que a maioria das empresas tinha interesse em usar a madeira de eucalipto no futuro, desde que tenha maiores informações e que o preço seja acessível.The main objective of this work was to analyze the perception of the manufacturers of the furniture center of Ubá-MG, Brazil on the use of eucalyptus wood for furniture production. The increasing environmental restraint on the use of wood from native forests has stimulated the use of reforestation plantings specially of eucalyptus. A questionnaire was made and applied to the undertakers of the furniture center of Ubá, who use solid wood for furniture production, including seventeen of the dining-room section, twenty-one of the bedroom section and six of the made-to-order furniture section. The experience of using eucalyptus wood was observed in 43.2% of the enterprises. The main factors that influenced its use were: the fact that the lumber comes from planted forest and have uniform characteristics, and the scarcity of wood from native forest. 88% of the enterprises that have never used eucalyptus wood have already learned about its potentialities but do not use it because of their little knowledge about it, the lack of suppliers, lack of consumer demand and high price. It was concluded that most enterprises have interest in the use of eucalyptus wood in the future, once they obtain more information and reasonable price.

Herein, we described for the first time, biosynthesis of silver nanoparticles (AgNPs) using pre-hydrolyzed liquor of Eucalyptus wood under ambient conditions. The pre-hydrolyzed liquor containing a high amount of metabolites such as polyphenols, hemicelluloses and its derivatives are mainly assisted for the reduction and stabilization process of Ag+ ions to AgNPs. The formation of AgNPs is monitored by recording the UV–vis spectrophotometer for surface plasmon resonance (SPR) peak observed at ∼415 nm. The intensity of SPR increased linearly with increasing the reaction time at ambient condition. X-ray diffraction (XRD) pattern of AgNPs reveals the formation of face-centered cubic structure. Field emission electron microscopy (FESEM) and transmission electron microscopy (TEM) images show the spherical shaped particles and narrow size distribution with an average diameter of 25–30 nm. The elemental analysis by energy dispersive X-ray (EDAX) analysis confirms the presence of Ag as the major amount and is found to be 82%. Analysis of the fourier transform infrared (FT-IR) spectra of the NPs revealed the presence of phytoconstituents from pre-hydrolyzed liquor adsorbed on the surface of AgNPs. Moreover, in vitro , antimicrobial activity is found to be effective for as-synthesized AgNPs on tested bacteria (viz., P. aeruginosa, S. aureus and E. coli ) followed by fungus ( C. oxysporum, P. chrysogenum, C. albicans and A.niger ). Thus, these results suggest the use of biosynthesized AgNPs as effective growth inhibitors for various biomedical applications. [ABSTRACT FROM AUTHOR]

Grain drying using firewood as fuel for air heating, with direct fire, is still widely used in Brazil. The combustion of organic material, such as wood, can generate polycyclic aromatic hydrocarbons (PAHs) which are known to have carcinogenic potential. In the present work corn grain drying was carried out at three drying air temperatures: 60 °C, 60/80 °C and 80 °C. Following the drying process, the presence and quantification of PAH in the corn grains was investigated. After extracting the PAHs of the matrix, the material was subjected to analysis by gas chromatography with mass detector. he results showed the presence of seven compounds: fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene and chrysene. [ABSTRACT FROM AUTHOR]

The impact of alkaline pretreatment at different alkaline charges (5%, 10% and 15% NaOH w/w, on dry basis) on the chemical composition of eucalyptus, sugarcane bagasse and straw were compared with the subsequent bioconversion into ethanol, using semi-simultaneous saccharification and fermentation (SSSF). By increasing alkaline charge in pretreatments, substantial amount of lignin, hemicelluloses and cellulose were fractionated. The chemical composition of biomasses was expressed based on the complete mass balance. The chemical transformation of biomasses during pretreatments was assessed by comparing the chemical composition of pretreated biomasses and their untreated counterparts. Pretreatments promoted delignification in the range of 11%–51% for eucalyptus, 22%–90% for bagasse, and 60%–99% for straw for the alkaline charges in the range of 5%–15% (NaOH w/w). The removal of lignin from bagasse and straw was higher than that from eucalyptus, which was due to the combined effect of higher frequency of both, the free phenolic groups and the ester bonds in grass lignin that made the lignin solubility escalate in alkaline conditions. It was also observed that bagasse had a removal by 37%–45% hemicelluloses and 0.8%–11% cellulose. For straw, higher amount of carbohydrates was removed, in the range of 55%–66% hemicelluloses and 19%–36% cellulose. Fragments of lignin and carbohydrates were converted into new structures called “pseudo-extractives” in eucalyptus during pretreatments. Pseudo-extractives and native extractives were quantified together, thus increasing the total extractives contents by 3.3 (5% NaOH), 3.5 (10% NaOH) and 2.9 (15% NaOH) times, in line with the original raw materials. Maximum ethanol yield and maximum volumetric productivity of ethanol were achieved for eucalyptus pretreated using 10% NaOH, bagasse pretreated using 15% NaOH and straw pretreated using 5% NaOH. At the optimal pretreatment condition, just about 51% glucose was released from pretreated bagasse. Sugarcane bagasse presented the highest values for the respective parameters, namely: 8.8 g L −1 ethanol concentration, 0.101 g ethanol /g biomass ethanol yield and 0.88 g L −1 h −1 volumetric productivity of ethanol. Alkaline charge proved to be an important control variable for alkaline pretreatments, with determinant effect on chemical transformations of biomasses and result on ethanol production. [ABSTRACT FROM AUTHOR]

An intensified reaction technology was investigated to achieve high concentrations of levulinic acid (LA) from eucalyptus wood. In the new process, the woody biomass was first pretreated in mild conditions to hydrolyze hemicellulose and recover xylose. The pretreated wood with a high content of cellulose was further treated under relatively severe conditions to produce LA and formic acid. The reaction solution was reused in treatment of new batches of biomass, resulting in high concentrations of LA (105 g/L) and formic acid (39 g/L), respectively. The lignin and humins were recovered as solid byproducts, which had an estimated high heating value of 25–27 MJ/kg in comparison with 18 MJ/kg of original wood. In the sequential repeated batch reactions, however, the LA yield deteriorated batch by batch. It was found out that the old LA in the reaction solution inhibited formation of new LA from glucose. In addition, some LA at high concentrations was lost due to its interactions with other intermediates and byproducts. [ABSTRACT FROM AUTHOR]

New lignin-degrading microorganisms and their enzymes can contribute to more efficient and environmentally sound use of lignocellulosic biomass in future biorefineries. In view of this, 127 endophytic fungi were isolated from eucalyptus trees. Strains were tested for their ability to produce ligninolytic enzymes in agar-plate medium containing ABTS, and 21 showed positive ABTS-oxidation. Positive strains in liquid medium confirmed that five produced laccase but no peroxidase activity. These strains were identified as Hormonema sp. and Pringsheimia smilacis , of the family Dothioraceae, Ulocladium sp. (Pleosporaceae) and Neofusicoccum luteum and Neofusicoccum australe (Botryosphaeriaceae). Laccase production by fungi of the family Dothioraceae is described here for the first time. To increase laccase production from these fungi, copper sulphate and ethanol were assayed as inducers. An increase in laccase activity of 85% was found for Hormonema sp. and N. luteum and 95% for N. australe. No increase was obtained for P. smilacis. A maximum temperature of 40 °C is recommended for possible biotechnological applications with these four strains at pH 2 for N. luteum and N. australe , pH 4 for Hormonema sp. and pH 4–5 for P. smilacis. [ABSTRACT FROM AUTHOR]

As dificuldades quanto ao uso da madeira do eucalipto, na forma sólida, estão baseadas na falta de conhecimentos de como trabalhar corretamente esse material. É preciso conhecer a estrutura da madeira e os parâmetros de usinagem para entender suas relações, que proporcionam os bons resultados em qualidade. O presente trabalho visou verificar as variações no sentido medula-casca de diferentes operações de usinagem e das dimensões das fibras da madeira de Eucalyptus grandis Hill ex. Maiden. A madeira foi proveniente de plantio comercial da Klabin Fabricadora de Papel e Celulose S.A., com 25 anos de idade. Os dados foram avaliados através de análises de variância e testes de médias. Além disso, realizaram-se as correlações de Pearson entre as operações de usinagem e as dimensões das fibras. Foram obtidos diferentes modelos de variação da medula para a casca. Nas operações de usinagem, pôde-se concluir que as condições de corte foram insuficientes para apresentar melhores qualidades das superfícies, podendo detacar as baixíssimas velocidades de corte, que produziram pré-clivagem. A madeira de Eucalyptus grandis apresentou resultados satisfatórios, mas inferiores aos do mogno e da imbúia. A utilização de operações como a moldura no topo (corte 90º-90º), moldura axial ";parada"; (corte 90º-0º) e perfilagem axial sinuosa com faca plana (corte 90º-0º, contra as fibras) permitem apreciar a usinabilidade da madeira, pois esta é usinada sob drásticas condições, podendo mostrar seu verdadeiro potencial.The difficulties to the use of eucalypt as solid wood are based on the lack of knowledge about the process of how to work correctly this material. It is necessary to know both the wood structure and wood workability parameters to better understand their relationships. Thus, this research aimed to identify the variation of wood machining property and the fiber morphology from pith to bark in 25-year-old Eucalyptus grandis Hill ex. Maiden. Data were evaluated through analysis of variance and tests of comparison of means. Then wood machining properties were correlated with fiber dimensions. Different standards of variation from pith to bark were obtained. For wood workability, it was conclued that cut conditions were considered insufficient to present better surface qualities, due to very low cutting velocities, which produced precleavage. Eucalyptus grandis wood presented satisfactory surface quality, but poorer than that of mahogany (Swietenia macrophylla R.A. King.) and Brazilian Walnut (Ocotea porosa (Nees ex.Mart.) Barroso). The operations, such as moulding in top (cut 90º-90º), axial moulding ";stopped"; (cut 90º-0º) and axial edge cutting with plane knife (cut 90º-0º against the fibers) allowed to better evaluate the workability than other properties, since wood is processed under drastic condictions, showing its true potential.

Heat treatment is often applied to some wood species to improve dimensional stability. This study evaluated the effect of heat treatment on some physical and mechanical properties and colour of Eucalyptus wood (Eucalyptus camaldulensis Dehn.), which has industrially high usage potential and large plantations in Turkey. Wood specimens from Tarsus, Turkey were subjected to heat treatment in varying temperatures and durations. After the heat treatment, hardness, swelling, ovendry density, and colour change of the wood specimens were tested in comparison with untreated specimens. The results showed that density, swelling, and hardness decreased with increasing treatment temperature and durations while heat treatment made the colour of the wood specimens darker