Search Results (3,399)

The emulsification of a molten fusible metal alloy in a liquid epoxy matrix with its subsequent curing is a novel way to create a highly concentrated phase-change material. However, numerous challenges have arisen. The high interfacial tension between the molten metal and epoxy resin and the difference in their viscosities hinder the stretching and breaking of metal droplets during stirring. Further, the high density of metal droplets and lack of suitable surfactants lead to their rapid coalescence and sedimentation in the non-cross-linked resin. Finally, the high differences in the thermal expansion coefficients of the metal alloy and cross-linked epoxy polymer may cause cracking of the resulting phase-change material. This work overcomes the above problems by using nanosilica-induced physical gelation to thicken the epoxy medium containing Wood’s metal, stabilize their interfacial boundary, and immobilize the molten metal droplets through the creation of a gel-like network with a yield stress. In turn, the yield stress and the subsequent low-temperature curing with diethylenetriamine prevent delamination and cracking, while the transformation of the epoxy resin as a physical gel into a cross-linked polymer gel ensures form stability. The stabilization mechanism is shown to combine Pickering-like interfacial anchoring of hydrophilic silica at the metal/epoxy boundary with bulk gelation of the epoxy phase, enabling high metal loadings. As a result, epoxy shape-stable phase-change materials containing up to 80 wt% of Wood’s metal were produced. Wood’s metal forms fine dispersed droplets in epoxy medium with an average size of 2–5 µm, which can store thermal energy with an efficiency of up to 120.8 J/cm³. Wood’s metal plasticizes the epoxy matrix and decreases its glass transition temperature because of interactions with the epoxy resin and its hardener. However, the reinforcing effect of the metal particles compensates for this adverse effect, increasing Young’s modulus of the cured phase-change system up to 825 MPa. These form-stable, high-energy-density composites are promising for thermal energy storage in building envelopes, radiation-protective shielding, or industrial heat management systems where leakage-free operation and mechanical integrity are critical. Full article

Lignocellulosic bio-based materials, such as wood, biocomposites, and natural fibers, exhibit desirable structural properties. This comprehensive review emphasizes the foundational and latest advancements in bioinspired improvement strategies, such as direct mineralization, biomineralization, lignocellulosic nanomaterials, protein-based treatments, and metal-chelating processes. Significant focus was placed on biomimetics, emulating natural protective mechanisms, with discussions on relevant topics including hierarchical mineral deposition, free-radical formation and quenching, and selective metal ion binding, and relating them to lignocellulosic bio-based material property improvements, particularly against fire and fungi. This review evaluates the effectiveness of different bioinspired processes: mineralized and biomineralized composites improve thermal stability, nanocellulose and lignin nanoparticles provide physical, thermal, and chemical barriers, proteins offer biochemical inhibition and mineral templating, and chelators interfere with fungal oxidative pathways while simultaneously improving fire retardancy through selective binding with metal ions. Synergistic approaches integrating various mechanisms could potentially lead to long-lasting and multifunctional protection. This review also highlights the research gaps, challenges, and potential for future applications. Full article

Utilizing forestry and agricultural byproducts like wood and hemp residues advance sustainable additive manufacturing (AM), while reducing material costs. This study investigated the development and characterization of wood–sodium silicate composites incorporating hemp hurd and hemp fibers for AM applications. Formulations varied by wood fiber type (unsifted, 40 mesh, and pellet), sodium silicate concentration (50–60 wt%), and hemp hurd content (0–15 wt%). Properties evaluated include particle size and bulk density of the constituent materials, rheological behavior, extrusion performance, composite bulk density, and flexural and compressive strengths. Rheology and extrusion were largely influenced by the liquid content. Mixtures with low liquid content (50 wt% sodium silicate) had high motor power and low viscosity. As liquid content increased, motor power decreased, while viscosity increased up to 55 wt% and then decreased at 60 wt%. Mechanical properties correlated with particle size, where finer particles enhanced strength. A cost analysis was conducted using raw material prices to determine the economic feasibility of each formulation. Finally, the formulations were evaluated based on strength-to-cost ratios, extrudability and processability. The formulation with pellet wood fibers, 55 wt% sodium silicate, and 10 wt% hemp hurd achieved a high ratio of 73.0 MPa/$ while maintaining low motor power. This formulation offered additional benefits which are discussed qualitatively. Full article

To address the imbalance between the “ecological advantage” and “economic benefit” of wooden structure buildings, this study examines two structural construction methods utilizing inexpensive and readily available small-diameter round timber as the primary material. It demonstrates the advantages of these two structural systems in terms of material consumption, life cycle carbon emissions, and economic efficiency. Through the research methods and processes of “Preliminary analysis–Proposing the construction system–The feasibility analysis of structural technology–Efficiency assessment”, the sustainable wood structure technical system suitable for the development of China is explored. The main conclusions are as follows: (1) Employing the preliminary analysis method, this paper examines and analyzes construction cases that primarily utilize small-diameter round timber as the main material. It delineates specific construction types based on the characteristics of small-diameter round timber. Additionally, it technically reconstructs the methodology for utilizing small-diameter round timber. (2) Two lattice structural systems are proposed, leveraging the mechanical properties and fundamental morphological characteristics of inexpensive and readily available small-diameter round timber of fast-growing Northeast larch. The technical feasibility of these two small-diameter log structure systems is validated through simulation analysis of their spatial threshold suitability. (3) This study conducted a comprehensive comparison between the two small-diameter round timber structural systems and the conventional grain-parallel glued laminated timber (Cross-Laminated Timber) frame structural systems. The analysis was performed from three perspectives. As the primary structural material, grain-parallel glued laminated timber frame structural systems exhibits significant advantages in terms of timber utilization per unit area of the structural system. From a life cycle carbon emission analysis perspective, compared to grain-parallel glued laminated timber frame structures, small-diameter round timber structures can achieve carbon emission reductions ranging from 79.19% to 97.74%. Additionally, the unit area cost of small-diameter round timber structures is reduced by 21.02% to 40.42% relative to grain-parallel glued laminated timber frame structures. Consequently, it can be concluded that small-diameter round timber structural systems possess technical feasibility and construction advantages for small and medium-sized buildings, offering practical value in optimizing technical systems to meet the objective needs of ecological construction. Full article

Polypropylene (PP) nonwovens are widely used as filtration layers in surgical face masks, but their hydrophobic, inert surfaces limit their ability to attach functional coatings that adjust pore size and improve mechanical filtration. Herein, we exploit cellulose derived from sugarcane debris to construct nanocellulose coatings that modify the surface properties of PP mask nonwovens without altering the underlying fibre architecture. Cellulose pulp was fibrillated to cellulose nanofibres (CNFs) and functionalised to yield TEMPO-oxidised nanofibres (TCNFs) and cationic nanofibres (CCNFs). All these nanofibres retain a cellulose I structure with a thermal stability of well above an 80–100 °C drying window. The three nanocelluloses exhibit distinct combinations of surface charge and wettability (ζ ≈ −9, −73, and +76 mV), with various hydrophobicity. Dip coating produces nanocellulose coating layers on PP, with uniform coverage at 1 wt% for TCNF and CCNF. CCNF inverts the negative surface charge of PP and maintains the positive charge at 86% relative humidity. Ethanol pretreatment of PP increases CCNF coating adhesion and preserves a continuous nanoporous CCNF film on the PP surface under humid conditions. Cytotoxicity assays indicate no detectable cytotoxicity for coated or uncoated nonwovens. This work establishes sugarcane-derived nanocellulose, particularly CCNF and TCNF, as a potential biocompatible surface coating for PP mask nonwovens. Full article

Biochar, a carbon-rich material produced through the pyrolysis of wood residues and agricultural byproducts, has carbon storage capacity and potential as a low-carbon construction material. This study predicts the compressive strength of cementitious composites in which cement is partially replaced with biochar using machine learning models. A total of 716 data samples were analyzed, including 480 experimental measurements and 236 literature-derived values. Input variables included the water-to-cement ratio (W/C), biochar content, cement, sand, aggregate, silica fume, blast furnace slag, superplasticizer, and curing conditions. Predictive performance was evaluated using Multiple Linear Regression (MLR), Elastic Net Regression (ENR), Support Vector Regression (SVR), and Gradient Boosting Machine (GBM), with GBM showing the highest accuracy. Further optimization was conducted using XGBoost, Light Gradient-Boosting Machine (LightGBM), CatBoost, and NGBoost with GridSearchCV and Optuna. LightGBM achieved the best predictive performance (mean absolute error (MAE) = 3.3258, root mean squared error (RMSE) = 4.6673, mean absolute percentage error (MAPE) = 11.19%, and R² = 0.8271). SHAP analysis identified the W/C and cement content as dominant predictors, with fresh water curing and blast furnace slag also exerting strong influence. These results support the potential of biochar as a partial cement replacement in low-carbon construction material. Full article

This systematic mapping review and bibliometric analysis examines Scopus-indexed research on computer vision, image processing, and deep learning applied to wood and timber materials and products. A rule-based Scopus search (TITLE-ABS-KEY, 9 December 2025), combining wood and timber terms with imaging and computer vision terminology, followed by duplicate removal and structured exclusions, retained 1019 papers (1983–2026, early access) covering surface inspection, internal imaging, species identification, processing operations (log-yard/sawmill/panels), automation, dimensional metrology, and image-based property/structure characterization. The papers were classified into nine application categories and three methodological classes using improved rule-based classification with weighted scoring and exclusion rules. Paper output continues to accelerate, with 63.7% of papers published since 2016; Wood Surface Quality Control dominates (48.3%), followed by 3D and Internal Wood Imaging (13.6%), Wood Microstructure and Characterization (10.1%), and Wood Species and Origin Identification (10.6%). Methodologically, classical computer vision prevails (73.6%). Deep learning accounts for 26.4% of the corpus overall and 48.8% of papers from 2023–2026 (early access), while classical computer vision remains prevalent (70.1%) across most categories; the dataset totals 11,961 citations (mean: 11.74 per paper). Validation on 97 papers showed 80.41% accuracy for methodological classification and 70.1% for application categories. We quantitatively map method evolution across the nine categories, introducing a tailored taxonomy and tracking the shift from classical vision to deep learning at the category level. The remaining gaps include dimensional measurement automation, warp detection, sawing optimization, and benchmark datasets, with future directions emphasizing Vision Transformers, multi-modal sensing, edge computing, and explainable AI for certification. Full article

The increasing energy crisis demands sustainable functional materials. Wood, with its natural three-dimensional porous structure, offers an ideal renewable template. This study demonstrates that microstructural engineering of wood is a decisive strategy for enhancing magnetothermal conversion. Using eucalyptus wood, we precisely tailored its pore architecture via delignification and synthesized Fe₃O₄ nanoparticles in situ through coprecipitation. We systematically investigated the effects of delignification and precursor immersion time (24, 48, 72 h) on the loading, distribution, and magnetothermal performance of the composites. Delignification drastically increased wood porosity, raising the Fe₃O₄ loading capacity from ~5–6% (in non-delignified wood) to over 14%. Immersion time critically influenced nanoparticle distribution: 48 h achieved optimal deep penetration and uniformity, whereas extended time (72 h) induced minor local agglomeration. The optimized composite (MDW-48) achieved an equilibrium temperature of 51.2 °C under a low alternating magnetic field (0.06 mT, 35 kHz), corresponding to a temperature rise (ΔT) > 24 °C and a Specific Loss Power (SLP) of 1.31W·g⁻¹. This performance surpasses that of the 24 h sample (47 °C, SLP = 1.16 W·g⁻¹) and rivals other bio-based magnetic systems. This work establishes a clear microstructure–property relationship: delignification enables high loading, while controlled impregnation tunes distribution uniformity, both directly governing magnetothermal efficiency. Our findings highlight delignified magnetic wood as a robust, sustainable platform for efficient low-field magnetothermal conversion, with promising potential in low-carbon thermal management. Full article

This study aims to evaluate the potential of circular economy principles in earth-based construction using an experimental rammed earth building located in Pasłęk, Poland as a case study. The research focuses on end-of-life scenarios for earth materials, with particular emphasis on rammed earth, adobe, and compressed earth blocks stabilized with Portland cement. A scenario-based life-cycle assessment (LCA) was conducted to compare alternative demolition and reuse strategies, including manual and mechanical deconstruction, as well as on-site and off-site material reuse. Greenhouse gas emissions associated with demolition (Module C1) and transport (Module C2) were estimated for each scenario. The results indicate that manual deconstruction combined with local, on-site reuse leads to the lowest carbon footprint, whereas off-site reuse involving long-distance transport significantly increases greenhouse gas emissions. In addition, qualitative reuse pathways were identified for wood, glass, ceramics, and insulation materials. The study reveals a lack of standardized technical procedures for the recovery and reuse of stabilized earthen materials after demolition and highlights the importance of integrating end-of-life planning into the early design phase using digital tools such as material passports and BIM. The findings demonstrate that properly designed rammed earth systems can provide a viable low-tech solution for reducing construction waste and supporting circular material flows in the built environment. Full article

This study examines European citizens’ attitudes and willingness to pay for biobased materials in construction and renovation. A survey conducted across nine countries with over 4500 participants revealed a generally positive attitude toward using recycled materials, such as glass and wood, while skepticism persisted toward biobased options. Many respondents expressed willingness to pay more for biobased and innovative materials, though a notable proportion would pay less for recycled and reused components. The findings highlighted significant national differences in attitudes and preferences, underscoring the influence of socioeconomic and cultural factors on the adoption of circular economy practices in the construction sector. Full article

Historic timber buildings rely heavily on naturally aged wood. However, the influence of long-term environmental exposure on the thermal behavior and fire performance of such structural members remains insufficiently understood. This study evaluates the effect of natural aging on heat transfer, charring development, and the phase-change interval of free water in larch wood (Larix decidua). Medium-scale radiant panel tests were conducted on fresh and naturally aged timber beams. Internal temperatures were recorded at multiple depths and analyzed using derivative-based T-history methods. The temperature profiles of aged and fresh larch were highly comparable, exhibiting a strong correlation (R² = 0.89). Aged wood, characterized by a slightly higher density, showed shallower thermal gradients and a marginally lower average charring rate (0.63 mm·min⁻¹) compared with fresh wood (0.65 mm·min⁻¹). In both materials, the charring rate decreased with depth. The phase-change interval of free water differed markedly: fresh wood showed water evaporation between 107.8–142.1 °C, whereas aged wood exhibited an earlier and narrower interval (93.6–116.3 °C), indicating facilitated dehydration due to microstructural degradation. Overall, natural aging did not significantly impair fire-relevant thermal properties, suggesting that aged larch retains charring resistance comparable to that of fresh wood and can reliably perform in passive fire protection applications for heritage structures. Full article

In modern construction, natural materials with a low carbon footprint and full recyclability are becoming increasingly important. A typical group here is products made from solid wood, including glued wood, plywood, and wood-based composites. With their many advantages, however, they all burden the environment with the costs of production processes, as well as the need to use harmful chemicals (adhesives and impregnants). Solid wood is devoid of these disadvantages; however, it is often treated as a rather archaic material. One of the arguments here is its low durability compared to, e.g., glued wood. The article discusses the durability of solid wood using the example of a group of wooden churches preserved in Poland, in Upper Silesia. Some of these buildings are over five hundred years old, making them a reliable source of information about the durability of the material from which they were built. A total of 85 churches, at least 200 years old, were analyzed, evaluating the technical state of the main load-bearing elements of their structures. In view of the number of facilities and the inability to conduct tests in most of them, the assessment was limited to a visual inspection of the technical condition, carried out by an experienced building expert. The assessment estimated the area of corrosion damage, probed its depth, and measured the depth of cracks. The relationship between their technical condition and the environmental conditions in which they were used was described and discussed. In this way, both the threats to the durability of solid wood and the ways to keep it in good condition for hundreds of years were identified, refuting the thesis that solid wood is a material with low durability. Its use in structural elements therefore supports efficient resource management and contributes to sustainable construction, especially in small and medium-sized buildings. Full article

Thermally compressed fast-growing wood exhibits superior mechanical properties, presenting a sustainable and cost-effective alternative to solid wood. However, to prevent structural damage and achieve higher densification during this process, effective pretreatment is essential. This study systematically evaluates the efficacy of hydrothermal and alkaline sulfite pretreatments in modifying Chinese fir (Cunninghamia lanceolata Hook.) and poplar (Populus tomentosa Carr.). The resulting compressed wood was comprehensively characterized in terms of mass loss, mechanical strength, microstructure, chemical composition, and cellulose crystallinity. Results indicate that, under the conditions tested, alkaline sulfite pretreatment was more effective than hydrothermal pretreatment in enhancing the material properties of densified wood, with peak density, compressive strength, and hardness achieved after 5 h for fir and 3 h for poplar, respectively. The results obtained under the present experimental conditions support the fact that alkaline sulfite pretreatment is an effective approach for producing densified wood with enhanced mechanical properties, suggesting its potential suitability for higher-value applications. Full article

Three painted valuable wood sculptures from conventual collections in Apulia (Southern Italy), made between the beginning of the 17th century and the first half of the 18th century, were studied to shed light on the pictorial materials and techniques of the Neapolitan Baroque sculpture in Southern Italy. A multi-analytical approach was implemented using integrated micro-invasive techniques, including polarized light microscopy (PLM) in ultraviolet (UV) and visible (VIS) light, scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS), Fourier-Transform Infrared (FTIR) spectroscopy, and pyrolysis–gas chromatography/high-resolution mass spectrometry (Py-GC/HRMS). The stratigraphic sequences were microscopically identified, and the pictorial layers were discriminated on the basis of optical features, elemental compositions, and mapping. Organic components were detected by FTIR as lipids and proteinaceous compounds for binders, while terpenic resins were detected as varnishes. Accordingly, PY-GC/HRMS identified siccative oils, animal glue, egg, and colophony. The results allowed the identification of the painting techniques used for the pictorial films and the ground preparation layers and supported the distinction between original and repainting layers. The results of this multi-analytical approach provide insights into Baroque wooden sculpture in Southern Italy and offers information to support restorers in conservation works. Full article

Nanoparticle-mediated photothermal conversion exploits the unique light-to-heat transduction properties of engineered nanomaterials to address challenges in energy, water, and healthcare. This review first examines fundamental mechanisms—localized surface plasmon resonance (LSPR) in plasmonic metals and broadband interband transitions in semiconductors—demonstrating how tailored nanoparticle compositions can achieve >96% absorption across 250–2500 nm and photothermal efficiencies exceeding 98% under one-sun illumination (1000 W·m⁻², AM 1.5G). Next, we highlight advances in solar steam generation and desalination: floating photothermal receivers on carbonized wood or hydrogels reach >95% efficiency in solar-to-vapor conversion and >2 kg·m⁻²·h⁻¹ evaporation rates; three-dimensional architectures recapture diffuse flux and ambient heat; and full-spectrum nanofluids (LaB₆, Au colloids) extend photothermal harvesting into portable, scalable designs. We then survey photothermal-enhanced thermal energy storage: metal-oxide–paraffin composites, core–shell phase-change material (PCM) nanocapsules, and MXene– polyethylene glycol—PEG—aerogels deliver >85% solar charging efficiencies, reduce supercooling, and improve thermal conductivity. In biomedicine, gold nanoshells, nanorods, and transition-metal dichalcogenide (TMDC) nanosheets enable deep-tissue photothermal therapy (PTT) with imaging guidance, achieving >94% tumor ablation in preclinical and pilot clinical studies. Multifunctional constructs combine PTT with chemotherapy, immunotherapy, or gene regulation, yielding synergistic tumor eradication and durable immune responses. Finally, we explore emerging opto-thermal nanobiosystems—light-triggered gene silencing in microalgae and poly(N-isopropylacrylamide) (PNIPAM)–gold nanoparticle (AuNP) membranes for microfluidic photothermal filtration and control—demonstrating how nanoscale heating enables remote, reversible biological and fluidic functions. We conclude by discussing challenges in scalable nanoparticle synthesis, stability, and integration, and outline future directions: multicomponent high-entropy alloys, modular photothermal–PCM devices, and opto-thermal control in synthetic biology. These interdisciplinary innovations promise sustainable solutions for global energy, water, and healthcare demands. Full article