European Journal of Wood and Wood Products最新文献

Noise pollution is a growing concern in urban environments, driving the need for sustainable and effective acoustic materials. Wood, a naturally abundant and lingocellulosic material, exhibits sound absorption properties influenced by its porosity, gas permeability, and structural integrity. This study aimed to investigate the relationship between these properties and the sound absorption coefficient (SAC) of five wood types: Coconut (Cocos nucifera L.), Hackberry (Carya ovata), Malas (Homalium foetidum Roxb.), Oak (Quercus mongolica Fisch.), and Paulownia (Paulownia tomentosa). Using the two-microphone transfer function method, SAC was measured across a frequency range of 250–4000 Hz, both with and without back air cavities (0–4 cm). Additional analyses included porosity determination via helium pycnometer, gas permeability using a capillary flow porometer, and surface morphology assessment with a 3D optical profilometer. Results showed that back air cavities significantly enhanced low-frequency SAC. Hackberry and Oak achieved the highest Noise Reduction Coefficients (NRC) values (0.55 and 0.53, respectively at a 4 cm cavity depth). Porosity was critical for low-frequency absorption in Coconut (80.91%) and Paulownia (55.56%), while high permeability and large pore sizes favored low-frequency performance in Oak and Hackberry. Malas demonstrated balanced acoustic properties across frequencies due to its intermediate porosity and diffuse pore structure. This research highlights the novelty of correlating wood anatomy with acoustic behavior and optimizing back air cavity depth to tailor performance. The findings provide valuable insights for developing eco-friendly, wood-based acoustic materials for applications in construction, interior design, and noise mitigation solutions.

This study explores tannin and caffeine, natural compounds with inherent antifungal properties, as scalable treatments to enhance the physical and mechanical performance of oriented strand board (OSB). Unlike previous research that primarily focused on durability, this work evaluates the effects of these bio-based treatments on leaching resistance, internal bond strength (IB), bending properties, water absorption, thickness swelling, and vertical density profile (VDP). The results demonstrate significant improvements over commercially available OSB, particularly in mechanical performance. Post-leaching, both treatments exhibited superior IB, with tannin-treated panels achieving the highest IB value (0.27 MPa). The bending analysis revealed that caffeine-treated panels that were not subjected to leaching achieved the highest modulus of rupture (MOR, 62.54 MPa) and modulus of elasticity (MOE, 10.36 GPa). Both treatments retained significantly higher MOR and MOE values post-leaching compared to the industrial reference and untreated panels. Water absorption and thickness swelling were comparable among tannin-treated, caffeine-treated, and untreated panels but were significantly lower than those of the industrial reference, which was included for general benchmarking purposes alongside the laboratory-made control. VDP analysis showed caffeine-treated panels had the lowest density prior to leaching, whereas tannin-treated panels maintained the highest density after leaching. These findings highlight tannin and caffeine as effective and scalable treatments, providing a sustainable alternative as functional additives for industrial engineered wood product manufacturing.

Semi-non-destructive drilling resistance instruments have been widely adopted for timber testing and forestry for wood quality assessments. The accuracy of a drilling resistance tool for predicting wood density may be affected by needle (drill) wear, and there is limited information regarding the wear behaviour of drill bits in wood resistance drilling. It is unknown when changes in needle sharpness and diameter become critical for quantifying wood density. To measure the effect of Resi needle wear, an IML Resi PD 500 was used to obtain cross-sectional traces of Southern Pine (Pinus elliottii var. elliottii (Engelm) × Pinus caribaea var. hondurensis (Sénéclauze)) average outerwood density: 519 kg/m³ and Spotted Gum (Corymbia citriodora subsp. variegata (F. Muell.)) average outerwood density: 779 kg/m³ logs. Southern Pine was tested with feed speeds of 200 cm/min at 3500 rpm and 100 cm/min at 5000 rpm. Spotted Gum was tested with a feed speed of 70 cm/min at 5000 rpm. A new needle was used for each setting. The effect of needle wear was tested after 0, 100, 200, 300, 400, 500, and 600 m of drilling depth. There was no effect on drilling resistance values up to 600 m of drilling length with feed speed 200 cm/min and 3500 rpm settings for Southern Pine. This would result in 2000 drilling measurements of 30 cm diameter trees. With alternative setting for Southern Pine with a setting of 100 cm/min feed speed and 5000 rpm, the increase in amplitudes was not significant until 300 m of drilling, after which, at 400 m, the amplitude increased by 2% (9.8 kg/m³), and after 600 m, the amplitude increased by 3.1% (15.2 kg/m³). For the hardwood Spotted Gum, the amplitude decreased by 0.9% (2.3 kg/m³) after 100 m, and after 300 m, the amplitude decreased by 3.3% (8.2 kg/m³). After 300 m, it was not possible to drill Spotted Gum due to extensive needle wear. The study highlighted the importance of needle wear in resistance drilling, providing guidance for reliable needle use to improve measurement accuracy and wood quality assessment.

Fast-grown plantation wood species such as poplar (Populus deltoides) are widely available but inherently possess poor decay resistance and limited mechanical strength which restricts its end-use applications. This study focuses on enhancing the properties by impregnating poplar wood with polyvinyl acetate (PVAc) resin fortified with nano hexagonal boron nitride (h-BN). The vacuum-pressure impregnation process was followed for treatment and the treated samples were evaluated for fungal decay resistance against brown rot and white rot fungi, as well as density, water absorption, surface hardness, compressive strength and thermal stability. Nanoparticles distribution within the wood microstructure was analysed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) mapping. Results showed that h-BN fortification of PVAc with different concentrations further improved the properties of poplar wood. These findings demonstrate that h-BN-PVAc impregnation is a promising modification method for producing a wood with enhanced properties for indoor wood products from fast-grown species which can be promising material towards sustainable development.

The European beech (Fagus sylvatica L.) is one of the most economically and ecologically important deciduous tree species in Europe. However, there is a lack of scientific knowledge regarding quality of wood growing on former agricultural land exists in the case of European beech. Therefore, this study aimed to evaluate the wood properties of European beech growing on former agricultural land compared to standard forest stands in north-western Poland. In total 2457 specimens were tested in mechanical strength and around 1000 for dimensions of micro and macrostructural wood elements. In the case of the most important parameter – the wood density, no significant differences were found between values observed in standard forest land (0.722 g/cm³) and afforested farmland (0.701 g/cm³). Land use did not significantly influence MOR nor MOE. However, higher values for these parameters were observed on forest land. The annual ring width was significantly wider on trees that grew on former agricultural land. The high variability with significant differences was obtained within the dimensions of vessels and fibers. The presented results have confirmed that European beech species is highly suitable for former agricultural land afforestation with high-quality wood production. These findings challenge the assumption that wood on afforested agricultural land has worse quality and support its viability for industrial purposes.

The chemical wood properties characterization of biomass feedstocks is important since it determines their potential for various chemical and energy applications. Willow (Salix sp.), a short-rotation hardwood species, is an interesting feedstock for such applications. It can represent an alternative raw material for non-sustainable resources, long-rotation trees, and agricultural biological materials. This research aimed to characterize the chemical properties of different wood tissues of willow and to develop a nondestructive method for their prediction. Wood, bark, and twig samples were sampled from six willow clones (Alberta, Canada). Extractives, cellulose, hemicellulose, and lignin contents were measured in sampled tissues by destructive chemical analysis tests using TAPPI standard test methods. The surface chemistry of the samples was analyzed by near-infrared spectroscopy. Partial least squares regression models were developed for quantitatively predicting wood chemical components. The coefficients of determination (R² calibration, R² cross-validation, and R² prediction) ranged from 0.66 to 0.99 for extractives, lignin, cellulose, and hemicelluloses. Carbohydrates (glucose, xylose, arabinose, and mannose) ranged between 0.98 and 0.99, demonstrating excellent predictive capability for these components. These results confirm the applicability of the developed models to predict the chemical properties of willow biomass. Furthermore, the prediction models apply to all investigated tissues, emphasizing consistency. These results provide the possibility to characterize the chemical properties of willow biomass using easily implemented, cost-effective, nondestructive, and rapid NIR equipment.

Understanding the effects of intact anatomical structures on bamboo shrinkage is crucial for mitigating shrinkage-induced defects in bamboo-based products. However, the effects of bamboo boundary layers (epidermis and pith ring) and their interactive mechanism with vascular bundles (VBs) remain unexplored. This study aims to quantify the effects of these boundaries on shrinkage and clarify how VB content modulates shrinkage under their joint constraints. The results show that the epidermis and the pith ring significantly inhibit radial and tangential shrinkage, while promoting longitudinal shrinkage. This inhibitory effect is further clarified by real-time monitoring, which reveals that the maximum tangential shrinkage (12%) occurred in the mid-VB content areas (37 VB% to 42 VB%). This phenomenon arises because boundary constraints restrict shrinkage in both VB-highest and VB-lowest areas, demonstrating that boundary effects override the influence of VB content gradients. Therefore, the epidermis and pith ring redistributed the shrinkage strain by restricting adjacent zones, thereby localizing maximum strain and crack formation in the mid-VB content areas. This study provides insights into the synergistic effects of anatomical boundaries and VB gradients on bamboo shrinkage, offering a theoretical basis to design low-shrinkage bamboo-based materials.

This research presented a comprehensive investigation of the influence of microwave (MW) treatment on the technological properties of maritime pine (Pinus pinaster) heartwood, including physical, microscopic, chemical, biological, and mechanical performance. Two MW configurations were applied: 400 W and 25 min (MW_400) and 700 W and 5 min (MW_700W). MW_400 treatment significantly improved wood impregnability, enabling 70% higher preservative uptake while maintaining low leaching (4%). The results indicated that MW_400 samples were more stable dimensionally than MW_700, which may be related to the reduction in hemicellulose (12%) and rise in lignin content (22%) of MW_400 samples. The synergistic effect of MW_400 combined with preservative treatment resulted in the highest biological resistance, with reductions in fungal mass loss of up to 54.4%, thereby classifying the wood as resistant. A reduced impact in bending strength (-1% for MW_400 and − 8% for MW_700), modulus of elasticity (-1% for MW_400 and − 4% for MW_700), and compressive strength (-12% for MW_400 and MW_700). MW treatment did not increase the wood’s brittleness. Overall, the MW_400 treatment demonstrated superior performance compared to MW_700, particularly when combined with preservative impregnation, resulting in improvements in dimensional stability and durability while preserving mechanical integrity. Hence, MW-treated wood samples present promising possibilities as construction materials, and MW technology can be a useful, sustainable, and modern methodology for wood treatment.

Understanding the effects of intact anatomical structures on bamboo shrinkage is crucial for mitigating shrinkage-induced defects in bamboo-based products. However, the effects of bamboo boundary layers (epidermis and pith ring) and their interactive mechanism with vascular bundles (VBs) remain unexplored. This study aims to quantify the effects of these boundaries on shrinkage and clarify how VB content modulates shrinkage under their joint constraints. The results show that the epidermis and the pith ring significantly inhibit radial and tangential shrinkage, while promoting longitudinal shrinkage. This inhibitory effect is further clarified by real-time monitoring, which reveals that the maximum tangential shrinkage (12%) occurred in the mid-VB content areas (37 VB% to 42 VB%). This phenomenon arises because boundary constraints restrict shrinkage in both VB-highest and VB-lowest areas, demonstrating that boundary effects override the influence of VB content gradients. Therefore, the epidermis and pith ring redistributed the shrinkage strain by restricting adjacent zones, thereby localizing maximum strain and crack formation in the mid-VB content areas. This study provides insights into the synergistic effects of anatomical boundaries and VB gradients on bamboo shrinkage, offering a theoretical basis to design low-shrinkage bamboo-based materials.

Wood dust generated by CNC machines during milling is hazardous to human health. This study aims to determine the wood dust emissions (PM2.5, PM10) according to the wood species, spindle speed (12000 rpm, 15000 rpm, and 18000 rpm), feed rate (3 m/min, 6 m/min, and 9 m/min), and cutting direction (contours, linear and spiral), and to predict them with machine learning algorithms. Oriental spruce (Picea orientalis L.) and Scots pine (Pinus sylvestris L.), known for their low and high dust emission values, respectively, were used as wood species. A blade with a diameter of 3 mm was preferred as a cutter for milling both wood species. The results of the analyses show that spindle speed, feed rate, and cutting direction parameters have a significant effect on PM. According to the PM2.5 and PM10 values, the highest wood dust emissions were measured at 121.42 µg/m³ and 173.02 µg/m³, respectively, in Scots pine wood material, with a spindle speed of 18,000 rpm, a feed rate of 3 m/min, and cutting direction being linear. The lowest wood dust emission was measured as 4.20 µg/m³ and 7.40 µg/m³ for PM2.5 and PM10 values, respectively, at a feed rate of 6 and 9 m/min, 15,000 rpm in Oriental spruce wood material under the conditions of cutting direction. However, the Cubist model performed best among the machine learning algorithms for predicting PM2.5 and PM10 levels. This study aims to provide data on wood dust emissions during CNC milling to inform the development of CNC parameter adjustments that minimize dust generation.