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In this thesis, wood loaded with a silica–titanium (Si-Ti) composite film was prepared using the sol–gel method in order to achieve improved wood with high hydrophobicity and photocatalytic activity under visible light. The factors affecting the structure and properties of the composite film, as well as the optimization process, were discussed. Infrared analysis revealed that the vibrational intensity of Si-O-Si, Ti-O-Ti, and Ti-O-Si telescopic vibration peaks increased with an increase in vinyltriethoxysilane (VETS). Additionally, the number of Ti-O-Ti telescopic vibration peaks also increased with an increase in VETS. Furthermore, the intensity of -NO3, Si-O-Si, and Ti-O-Ti telescopic vibrational peaks was enhanced with a higher dosage of nitric acid. Conversely, the intensity of -OH telescopic vibrational peaks decreased with an increase in drying temperature. XRD analysis showed that nitric acid could promote the transformation of TiO2 from amorphous to anatase, while SiO2 would reduce the grain size of anatase TiO2 and promote the growth of rutile TiO2. Additionally, wood surfaces loaded with Si-Ti composite film changed from hydrophilic to hydrophobic, with significant differences observed between different levels of each factor. The photocatalytic activity of surface-loaded Si-Ti composite films on wood was most affected by the amount of nitric acid, which influenced crystallinity of TiO2 and thus impacted the photocatalytic activity. Furthermore, changes in VTES dosage not only affected the crystalline phase of TiO2 and the grain size of Si-Ti composite film but also influenced the crystallinity of TiO2 through generating SiO2. Finally, based on optimal preparation process (titanium–alcohol ratio of 1:5, titanium–silicon ratio of 1:0.2, titanium–acid ratio of 1:0.5, and drying temperature of 100 °C), wood surfaces loaded with Si-Ti composite film achieved a contact angle up to 125.9° and exhibited a decolorization rate for rhodamine B under UV light reaching 94% within 180 min. [ABSTRACT FROM AUTHOR]

Mytilaria laosensis, a common fast-growing tree species in southern China, boasts excellent growth speed and attractive color and texture. However, due to its short growth cycle and high proportion of juvenile wood, it typically exhibits poor dimensional stability and low strength, which significantly limits its practical applications. This study uses vacuum impregnation to modify M. laosensis wood with polyethylene glycol (PEG), focusing on the effects and mechanisms of PEG with different molecular weights on wood properties. The results indicate that PEG enters the wood cell walls through capillary action and diffusion, forming hydrogen bonds with the free hydroxyl groups on cellulose and hemicellulose, which keeps the cell walls swollen and enhances dimensional stability. Post modification, the dimensional stability of M. laosensis wood improved, with an anti-swelling efficiency ranging from 61.43% to 71.22%, showing an initial increase followed by a decrease with increasing PEG molecular weight. The optimal PEG molecular weight for anti-swelling efficiency was 1500 Da, achieving 71.22%. The flexural modulus of elasticity and flexural strength of the treated wood also first decreased and then increased with increasing PEG molecular weight. Among them, the PEG1000-treated material showed the best performance, with the flexural modulus of elasticity increased by about 29% and the flexural strength increased by about 5% compared to untreated wood. Additionally, PEG, having a higher pyrolysis temperature than wood, raised the initial pyrolysis temperature and maximum pyrolysis rate temperature of M. laosensis wood, thus improving its thermal stability. These findings provide scientific evidence and technical support for the efficient utilization and industrialization of M. laosensis wood, promoting its widespread application and industrial development. [ABSTRACT FROM AUTHOR]

The effects of heat treatment on Cupressus funebris Endl. wood were examined under different combinations of temperature, time, and pressure. The chemical composition, crystallinity, and microstructure of heat-treated wood flour and specimens were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Vacuum heat treatment led to changes in the functional groups and microstructure of C. funebris wood, and the relative lignin content decreased with increasing treatment temperature, which was significant at lower negative pressures. Cellulose crystallinity showed a change rule of first increasing and then decreasing throughout the heat treatment range, and the relative crystallinity ranged from 102.46% to 116.39%. The cellulose treated at 120 °C for 5 h at 0.02 MPa had the highest crystallinity of 44.65%. These results indicate that although heat treatment can improve cellulose crystallinity, very high temperatures can lead to decreased crystallinity. The morphology and structure of the cell wall remained stable throughout the heat treatment range; however, at elevated temperatures, slight deformation occurred, along with rupture of the intercellular layer. [ABSTRACT FROM AUTHOR]

In this study, we proposed an improved Harris Hawks Optimization (IHHO) algorithm based on the Sobol sequence, Whale Optimization Algorithm (WOA), and t-distribution perturbation. The improved IHHO algorithm was then used to optimize the BP neural network, resulting in the IHHO-BP model. This model was employed to predict the bonding strength of heat-treated wood under varying conditions of temperature, time, feed rate, cutting speed, and grit size. To validate the effectiveness and accuracy of the proposed model, it was compared with the original BP neural network model, WOA-BP, and HHO-BP benchmark models. The results showed that the IHHO-BP model reduced the Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and Mean Absolute Percentage Error (MAPE) by at least 51.16%, 40.38%, and 51.93%, respectively, while increasing the coefficient of determination (R2) by at least 10.85%. This indicates significant model optimization, enhanced generalization capability, and higher prediction accuracy, better meeting practical engineering needs. Predicting the bonding strength of heat-treated wood using this model can reduce production costs and consumption, thereby significantly improving production efficiency. [ABSTRACT FROM AUTHOR]

In this study, environmentally friendly and low-cost biomass materials were selected as wood flame retardants. Three polyelectrolyte flame-retardant coatings made from chitosan (CS), tea polyphenols (TP), soybean isolate protein (SPI), and banana peel powder (BBP) were constructed on wood surfaces by layer-by-layer (LBL) self-assembly. The results of SEM-EDS and FT-IR analyses confirmed the successful deposition of CS-TP, CS-SPI, and CS-BPP on the wood surface, and the content of N element increased. The TG results showed that the initial decomposition temperature and the maximum thermal decomposition temperature of the coated wood specimens decreased, while the char residue increased significantly. This is due to the earlier pyrolysis of CS-TP, CS-SPI, and CS-BBP. This shows that the three polyelectrolyte flame-retardant coatings can improve the thermal stability of wood. The combustion behavior of the wood specimen was observed by exposure to combustion; the coated wood could self-extinguish within a certain period of time after ignition, and the flame-retardant performance was improved to a certain extent. SEM and EDS characterization analyses of the carbon residue after combustion showed that the coated wood charcoal layer was denser, which could effectively block heat and combustible gas. [ABSTRACT FROM AUTHOR]

Wood extractives have proven strong anti-oxidative properties which may be used to mitigate surface deterioration caused by photolytic effects and free radical formations. An interesting challenge regarding wood extractives is understanding how they behave in terms of treating natural wood surfaces to reduce anti-oxidative processes that arise from exposure to the main environmental factors. In this study, the possible efficacy of chestnut (Castanea sativa Mill.) extractives derived from native (CH) and thermally modified wood (TMT CH), as a means of protecting against UV exposure in poplar (Populus spp.) and spruce (Picea abies Karst.) wood, was evaluated. Chestnut wood was first thermally modified at 180 °C for 3 h, and the extractives were obtained by the accelerated solvent extraction technique (ASE) and subsequently used to treat wood surfaces. Samples were immersed in extractive solutions and exposed to artificial UV-weathering exposure, then contact angle and colour stability were monitored during the process. An FTIR analysis of the photo-degradation process of poplar and spruce surfaces was also executed. Extractives of TMT chestnut changed the total colour variation in both poplar and spruce wood. A much darker colour compared to the extractives of native wood was observed and an increase in ∆E* from 9.75 to 30.76 and 6.24 to 22.97 in poplar and spruce was calculated. The stability of the colour depended both on the surface wood and the type of extractive. The initial contact angle remained almost unchanged in the poplar wood surface and only slightly increased in spruce regardless of whether they were treated with extractives from native or TMT chestnut wood. A strong reduction in contact angle after the accelerated UV exposure test was observed, especially in spruce treated with CH extractives. FTIR analysis confirmed the lower levels of chemical degradation of surfaces observed by colorimetry, where TMT CH extractives formed more stable chemical bonds than native extractives. The comparative analysis in this study clarified the complex relationships between the effects of high-temperature modification of wood and the potential protective role of TMT extractives on some wood surfaces. [ABSTRACT FROM AUTHOR]

Castanopsis hystrix, a precious tree species in Southeast Asia, has the advantages of rapid growth and high-quality wood materials. However, there are problems such as its long breeding cycle and low efficiency, and being time-consuming, which greatly restricts the industrial development of C. hystrix. Performing genome selection (GS) for growth and wood traits for the early selection of superior progeny has great significance for the rapid breeding of new superior varieties of C. hystrix. We used 226 clones in the main distribution and 479 progenies within 23 half-sib families as experimental materials in this study. Genotyping datasets were obtained by high-throughput re-sequencing technology, and GS studies were conducted on the growth (tree height (H), diameter at breast height (DBH)) and wood (wood density (WD), fiber length (FL), and fiber length–width ratio (LWR)) traits. The coefficient of variation (CV) of five phenotypic traits ranged from 10.1% to 22.73%, the average CV of growth traits was 19.93%, and the average CV of wood traits was 9.72%. The Pearson correlation coefficients between the five traits were almost all significantly positive. Based on the Genomic Best Linear Unbiased Prediction (GBLUP) model, the broad-sense heritabilities of growth traits were higher than those of wood quality traits, and the different number of SNPs had little effect on the heritability estimation. GS prediction accuracy first increased and then reached a plateau at around 3K SNPs for all five traits. The broad-sense heritability of these five traits was significantly positively correlated with their GS predictive ability (r = 0.564, p < 0.001). Bayes models had better GS prediction accuracy than the GBLUP model. The 15 excellent progeny individuals were selected, and their genetic gain ranged from 0.319% to 2.671%. These 15 superior offspring individuals were 4388, 4438, 4407, 4468, 4044, 4335, 4410, 4160, 4212, 4461, 4052, 4014, 4332, 4389, and 4007, mainly from three families F5, F6, and F11. Our research lays out the technical and material foundation for the rapid breeding of new superior varieties of C. hystrix in southern China. [ABSTRACT FROM AUTHOR]

Fire is generally recognized as a major threat to the protection of historic timber architecture. Thus, there is an urgent need to study the fire properties of historic timber structures so as to better protect them in the future. Two types of commonly used wood species (pine and poplar) were selected as test specimens and three types of surface treatments (Chinese traditional coating, modern flame retardant, and a combination of the two methods) were applied. The specimens were subjected to a semi-full-scale fire test. The charring rate and the surface heating curve were calculated during the fire test to assess the flammability of various woods under different treatments. Results showed that the fire properties of traditional-coated wood were better than the modern type, but large amounts of smoke were released during combustion. The combination of traditional and modern methods did not significantly improve the overall fire properties and was even worse than the traditional treatment alone. At the same time, the fire properties of the modern method are highly correlated with the type of wood species used. The above results can provide informative advice on the selection of suitable surface treatments for the subsequent restoration of ancient buildings. [ABSTRACT FROM AUTHOR]

This study outlines a method of utilizing the finite element method and a simple mathematical model to predict the behavior of laminated veneer lumber (LVL) beams strengthened with composite sheets. The numerical models were created using the Abaqus 2017 software. The LVL was considered as a linearly elastic or elastic–plastic material, factoring in Hill's yield criterion. The composites were simulated as linearly elastic–ideally plastic materials. The mathematical models were predicated on the methodology of transformed cross-section. The theoretical and numerical outcomes were juxtaposed with previous empirical investigations. The comparison encompassed load-bearing capacity, stiffness, and deformation under peak force. Furthermore, presentations of normal stress maps in the LVL and composite have been illustrated. The derived maps were juxtaposed with the delineations of failure modes. An adequate correlation was identified between the theoretical, numerical, and empirical values in the case of beams reinforced with aramid, glass, and carbon sheets. The relative deviation varied from several to multiple percentages. This technique is not applicable for evaluating load-bearing capacity and deformation when only dealing with sheets with low elongation of rupture. This is a consequence of their premature failure. The proposed models may be utilized by researchers and engineers in the design of reinforcements for timber structures. [ABSTRACT FROM AUTHOR]

Nanocellulose (CNC) seems to be a promising surfactant, which, together with expandable graphite (EG), forms the essence of an effective natural-based fire-retardant wood coating. In our research, the most suitable composition of the mixture was tested concerning good solubility, dispersion, and consistency. Favorable results were achieved with the formulation composed of a 4% CNC alkaline solution with 80 wt.% of the selected EG. Subsequently, six different types of EG were used to prepare these wood fire-retardant coatings. The effectiveness of treatments was verified using a test with a radiant heat source, where the test samples' relative weight loss, relative burning rate, and surface temperature during 600 s were evaluated. All prepared formulations can be characterized as more or less equally effective. However, the best results were obtained with the EG of GG 200–100 N, where the mass loss of the sample was 8.10 ± 1.24%. Very good results were also achieved by graphite 25 E + 180 HPH (8.70 ± 0.89%), which is similar to the previous one, even according to the microscopic assessment of the coating as well as the expanded layer. The graphite type 25 K + 180 (8.86 ± 0.65%) shows the expanded layer's best adhesion, coating uniformity, and ease of application. The results of this work confirmed that the CNC coating itself has significant retardation effects. [ABSTRACT FROM AUTHOR]

Urea–formaldehyde resin was used as a wall material and Toddalia asiatica (L.) Lam extract was used as a core material to prepare urea–formaldehyde resin-coated Toddalia asiatica (L.) Lam extract microcapsules (UFRCTEMs). The effects of UFRCTEM content and the mass ratio of core-to-wall material (Mcore:Mwall) on the performance of waterborne coatings on poplar surfaces were investigated by adding microcapsules to the waterborne topcoat. Under different Mcore:Mwall of microcapsules, as the content of microcapsules increased, the glossiness and adhesion of the coatings gradually decreased, and the color difference value of the coatings gradually increased. The cold liquid resistance, hardness, and impact resistance of the coatings were all improved, and the roughness of the coatings increased. The antibacterial rates of the coatings against Escherichia coli and Staphylococcus aureus were both on the rise, and the antibacterial rate against Staphylococcus aureus was slightly higher than that against Escherichia coli. When the microcapsule content was 7.0% and the Mcore:Mwall was 0.8:1, the surface coating performance on poplar wood was excellent. The glossiness was 3.43 GU, light loss was 75.55%, color difference ΔE was 3.23, hardness was 2H, impact resistance level was 3, adhesion level was 1, and roughness was 3.759 µm. The cold liquid resistance was excellent, and resistance grades to citric acid, ethanol, and cleaning agents were all 1. The antibacterial rates against Escherichia coli and Staphylococcus aureus were 68.59% and 75.27%, respectively. [ABSTRACT FROM AUTHOR]

Fossil woods are preserved as calcareous permineralizations in the Upper Cretaceous Northumberland Formation on Collishaw Point, Hornby Island, British Columbia, Canada. They are well preserved, often including peripheral tissues, and reveal the diversity and structure of vegetation in the region ca. 72 million years ago. We describe a new genus and species based on two specimens. Two specimens were cut using a rock saw to expose the fossil wood in transverse and longitudinal sections. Thin sections were prepared using the cellulose acetate peel technique. Peels were mounted on slides with Eukitt mounting medium. Anatomical description follows the IAWA guidelines. We compared the anatomy of the fossils with that of other plants using data available in the published literature and the InsideWood database. The combination of wide vessels and high vessel frequency given the narrow diameter of the stem, combined with the abrupt increase in vessel diameter near the pith indicates this plant had hydraulic properties typical of a climbing plant (liana). The anatomy of the rays, the arrangement of the vessels and their pitting, and the thickness of the bark are also consistent with the climbing habit, but not diagnostic of any extant family. This is the second species of liana to be described from the Hornby Island assemblage, providing new information about the composition of structurally complex mixed conifer–angiosperm forests in the Late Cretaceous of western North America. [ABSTRACT FROM AUTHOR]

Rationale: This study overcomes traditional biomass analysis limitations by introducing a pioneering matrix‐free laser desorption/ionization (LDI) approach in mass spectrometry imaging (MSI) for efficient lignin evaluation in wood. The innovative acetic acid–peracetic acid (APA) treatment significantly enhances lignin detection, enabling high‐throughput, on‐site analysis. Methods: Wood slices, softwood from a conifer tree (Japanese cypress) and hardwood from a broadleaf tree (Japanese beech), were analyzed using MSI with a Fourier transform ion cyclotron resonance mass spectrometer. The developed APA treatment demonstrated effectiveness for MSI analysis of biomass. Results: Our imaging technique successfully distinguishes between earlywood and latewood and enables the distinct visualization of lignin in these and other wood tissues, such as the radial parenchyma. This approach reveals significant contrasts in MSI. It has identified intense ions from β‐O‐4‐type lignin, specifically in the radial parenchyma of hardwood, highlighting the method's precision and utility in wood tissue analysis. Conclusions: The benefits of matrix‐free LDI include reduced peak overlap, consistent sample quality, preservation of natural sample properties, enhanced analytical accuracy, and reduced operational costs. This innovative approach is poised to become a standard method for rapid and precise biomass evaluation and has important applications in environmental research and sustainable resource management and is crucial for the effective management of diverse biomass, paving the way towards a sustainable, circular society. [ABSTRACT FROM AUTHOR]

Funerary cremations in Roman times were important rites of passage that involved the use of fire to accompany the dead into the afterlife. In the present study, we investigated the wood fuel that was used to build cremation pyres and the foodstuffs involved in offerings and funerary feasts in a necropolis of Barcino (present-day Barcelona), dated to the 1st century CE and located at the Sant Antoni Market site. Our approach began with the analysis of wood charcoal and fruit/seed remains, which were preserved over time through carbonisation. These archaeobotanical remains offer valuable insights into the selection of woody species and the condition of wood logs used for cremations. Additionally, they shed light on the food composition of offerings and feasts in this area of the Mediterranean coast, where data on such practices are scarce. The anthracological analysis of different combustion structures revealed that the principal taxon used for the stacks was evergreen oak, with deciduous oak playing a significant role during the initial use of the necropolis. Dendro-anthracological analysis indicated that medium to large diameters wood logs of deciduous oak obtained from mature individuals were commonly employed. Moreover, charcoal analysis suggested the use of pruning remains from fruit trees such as olive, grapevine, walnut, plums, and members of the apple family, providing evidence of arboriculture practices in the city. Additionally, various minor woody species (Aleppo and mountain pines, juniper, cypress, mastic, and rockroses) may have had several functions, including symbolic sensory aspects relating to smell and good flammability, the constitution of small objects or furniture placed on the stack (boxwood), and fire kindling or decoration (mastic, rockroses, honeysuckle, and laurustinus). Carpological analysis indicated that the most abundant offerings and/or feast remains consisted primarily of cultivated fruits such as figs, walnuts, and grapes, while pulses and cereals were comparatively scarce or absent. Finally, a noteworthy quantity of Arbutus berry remains was recorded, marking the first occurrence of such findings in similar Roman contexts to date. [ABSTRACT FROM AUTHOR]

The aim of this paper is to provide new data on forest management and arboricultural practices in the Roman and Late Antique periods in the north-eastern Iberian Peninsula. In this study, the waterlogged branches found in three wells at the sites of Iesso and Vilauba in the northeast of the Iberian Peninsula were analysed. To determine management practices the roundwood method, based on the correlation between age and diameter, has been applied. The study has revealed the presence of a wide range of species collected on surrounding forests, especially in riparian forest. Moreover, it is remarkable the abundance of fruit trees at both sites, being the most abundant Prunus sp. The comparison of the archaeological branches with a reference collection of modern twigs from cultivated and non-managed individuals of the Prunaceae family, Salix sp. and Sambucus nigra , has provided clear evidence of management practices in these taxa. In addition, direct evidence of pruning was observed on some branches of Vitis vinifera. [ABSTRACT FROM AUTHOR]

Paleoclimate reconstructions from the Holocene are important for defining baseline conditions in order to interpret and contextualize the effects of modern climate change. Such records are particularly lacking for Siberia, a region that represents ~ 50% of the Arctic. In addition, the majority of proxy-based paleoclimate reconstructions for the Holocene represent mean annual conditions, and few quantify winter temperature, which is particularly important for predicting the effects of global warming in Arctic environments. Here we provide the first quantitative proxy reconstruction of precipitation and temperature for both summer and winter for 3000 years ago via novel high-resolution intra-annual carbon and oxygen isotope measurements across annual growth rings of fossil wood mummified within the permafrost of far northeastern Siberia. We found that the site experienced greater precipitation year-round (~ 10% increase in summer and ~ 30% increase in winter), cooler summer temperatures, and warmer winter temperatures, compared with today. Our findings indicate that warmer winter temperatures (+ 3.0 °C above early twentieth century values) in the Arctic 3000 years ago drove higher mean annual temperature by up to 1 °C, despite the existence of cooler summers, a similar phenomenon to what is observed within today's Arctic environments, and past intervals of extreme global warmth. [ABSTRACT FROM AUTHOR]

Wood constantly interacts with the surrounding, locally varying climate, leading to changes in the moisture content. Advanced simulation tools can predict the two-dimensional moisture distributions caused by these changing climate conditions within wood cross sections over time. However, there is a notable absence of systematic simulation results for diverse climatic conditions and various wood cross sections. This study seeks to bridge this gap in research. Here, we present moisture fields in three solid timber and three glued laminated timber cross sections in Austria and show the effect of the location and the altitude on the moisture content distribution. The results reveal decreasing influence of the location on the moisture content development with increasing cross section size, and primarily the altitude affecting the moisture content. In addition, the results are compared with the standard for the design of timber–concrete composite structures (ONR CEN/TS 19103), revealing appropriate values in most of the cases. Only for cross sections with a width of 14 cm and larger, assigned to a specific region, the standard value is assumed underestimated. Furthermore, the distribution of moisture gradients, which are related to the crack depth development, are analyzed for Austria, demonstrating the influence of mountain areas in the moisture gradient development. [ABSTRACT FROM AUTHOR]

Encapsulating luminescent dyes within delignified wood templates is a promising strategy for developing wood-based composite luminescent materials. However, the interactions between the nanopore structure of delignified wood, the loading efficiency of luminescent dyes, and the resulting luminescent properties of these composites remains unclear. In this study, we developed a series of wood-based luminescent composites using delignified wood templates as a dispersion platform for encapsulating classical organic fluorescent dyes. By extensively exploring the interrelationships among the delignification degree, organic dye loading efficiency, and luminescence properties, we uncovered the influence of delignified wood templates on the luminescent characteristics of wood-based luminescent composites. Furthermore, we demonstrated that the luminescent color could be controlled by encapsulating varying proportions of blue-, green- and red-fluorescent dyes, thus enabling the achievement of full-color fluorescence in wood-based luminescent composites. These wood-based luminescent composites hold great promise for applications in data anti-counterfeiting and light-emitting diode technology, offering valuable theoretical support for the development and utilization of innovative wood-based luminescent composites. [ABSTRACT FROM AUTHOR]

Water evaporation‐induced electricity generators (WEIGs) are promising as self‐powered electronic devices, as they can harvest green, small‐grade, and ubiquitous hydrovoltaic energy in ambient environment to electricity. Here, biodegradable wood‐based WEIGs with high performance are reported by removing lignin and hemicellulose from balsa wood (BW) with more exposed cellulose nanofibrils. Delignified BW (DBW) and cellulosic BW (CBW) display significant enhance in open circuit potential (Voc) and short circuit current (Isc) due to increased specific surface area, hydrophilicity, and surface charge density. The electricity‐generating performance of CBW‐based WEIG (CBWG) is not stable due to its structural collapse. DBW‐based WEIG (DBWG) shows a steady electricity output and fast responsivity to ambient environments, such as humidity, temperature, light, and wind. Therefore, DBWGs can be employed as self‐powered environmental sensors. The effects of different kinds of electrolytes with varied concentrations on the performance of DBWG are also studied. The DBWG (40 mm × 40 mm × 2 mm) displays a Voc of 0.77 V and Isc of 148 µA in 1.2 m CaCl2 solution. In this study, all wood‐based sustainable WEIGs with high electricity generating performance are facilely prepared and are promising for remote self‐powered environmental sensors and power sources. [ABSTRACT FROM AUTHOR]

The tomb of Marquis Yi of Zeng was unearthed in 1978 at Leiguudun in Suizhou City, Hubei Province, China. This is the largest wooden coffin in rock pit and vertical cave in the Warring States period in China. The large wooden coffin components provide reliable material data for the study of the feudal burial system in the pre-Qin period and have high value. In this paper, the wooden coffin excavated from the tomb of Marquis Yi of Zeng was studied. By understanding the composition of wood, studying the weight gain rate, shrinkage rate, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and compression resistance, the wood reinforced by rosin and epoxy resin was compared, and the reinforcement effect and principle of the two reinforcement methods were discussed. The study found that the wood properties of rosin reinforced group were better than those of epoxy reinforced group in the aspects of compressive strength, weight gain rate and volume shrinkage rate, and the mechanical properties of wood were significantly improved. In addition, methanol or ethanol can be used to dissolve the rosin shellac in this strengthening process, which can achieve reversible strengthening treatment. The results provide valuable examples and research ideas for the selection of different conservation techniques of large wooden cultural relics unearthed in the middle and lower reaches of the Yangtze River during the Warring States Period. [ABSTRACT FROM AUTHOR]

China has abundant straw resources, however, most of them have not been effectively developed and utilised, resulting in a waste of resources. Therefore, the development of straw puffing technology and its efficient use has become an unavoidable trend. This paper firstly intro- duces the main components of crop straw, then gives an in-depth overview of the working principle of screw extruder, details the research history of single-screw, twin-screw and three-screw extruders in the field of straw extrusion, and analyses the advantages and disadvantages of various types of extruders. At the same time, a comprehensive summary of the influencing factors in the expansion process is also presented. Based on the application of straw bulking, the article looks forward to the utilisation of straw in pulping, composite boards and ethanol, providing theoretical guidance for the efficient utilisation of straw. [ABSTRACT FROM AUTHOR]

Over recent decades, the southeastern United States (Southeast) has become increasingly well represented by the terrestrial climate proxy record. However, while the paleo proxy records capture the region's hydroclimatic history over the last several centuries, the understanding of near surface air temperature variability is confined to the comparatively shorter observational period (1895‐present). Here, we detail the application of blue intensity (BI) methods on a network of tree‐ring collections and examine their utility for producing robust paleotemperature estimates. Results indicate that maximum latewood BI (LWBI) chronologies exhibit positive and temporally stable correlations (r = 0.28–0.54, p < 0.01) with summer maximum temperatures. As such, we use a network of LWBI chronologies to reconstruct August‐September average maximum temperatures for the Southeast spanning the period 1760–2010 CE. Our work demonstrates the utility of applying novel dendrochronological techniques to improve the understanding of the multi‐centennial temperature history of the Southeast. Plain Language Summary: Tree‐ring data are important sources of paleoclimate information, which allow for the longer‐term evaluation of modern climate values and trends. Compared to much of North America, the Southeastern United States (Southeast) contains substantially fewer paleoclimate records from tree rings, and no estimates of past temperature variability which extend before the observational period. Employing a recently developed technique, which uses light reflectance properties of wood to obtain a representative metric of tree‐ring density, we develop a network of temperature‐sensitive tree‐ring records across the Southeast. These records enable us to reconstruct late summer maximum temperatures across the region spanning the period 1760–2023 CE. As few ground‐based, pre‐instrumental temperature records previously existed for this region, our reconstruction allows for an improved understanding of the region's multi‐centennial climatic history. Key Points: Maximum latewood blue intensity from tree rings can effectively be used to develop paleotemperature estimates for the southeastern USThe fidelity of tree‐ring density parameters for paleoclimate reconstruction are influenced by disturbance regimes and microsite conditionsCompared to the last 260 years, regional 20th‐century maximum late summer temperatures are not characterized by unprecedented positive trend [ABSTRACT FROM AUTHOR]

With the increasing production of municipal sewage sludge (MSS) worldwide, the development of efficient and sustainable strategies for its management is crucial. Pyrolysis of MSS offers several benefits, including volume reduction, pathogen elimination, and energy recovery through the production of biochar, syngas, and bio-oil. However, the process can be limited by the composition of the MSS, which can affect the quality of the biochar. Co-pyrolysis has emerged as a promising solution for the sustainable management of MSS, reducing the toxicity of biochar and improving its physical and chemical properties to expand its potential applications. This review discusses the status of MSS as a feedstock for biochar production. It describes the types and properties of various co-substrates grouped according to European biochar certification requirements, including those from forestry and wood processing, agriculture, food processing residues, recycling, anaerobic digestion, and other sources. In addition, the review addresses the optimization of co-pyrolysis conditions, including the type of furnace, mixing ratio of MSS and co-substrate, co-pyrolysis temperature, residence time, heating rate, type of inert gas, and flow rate. This overview shows the potential of different biomass types for the upgrading of MSS biochar and provides a basis for research into new co-substrates. This approach not only mitigates the environmental impact of MSS but also contributes to the wider goal of achieving a circular economy in MSS management. [ABSTRACT FROM AUTHOR]

In recent decades, wood drying has emerged as an important method to ensure wood quality and improve wood utilization. However, the addition of modifiers to wood can hinder the transfer of moisture, making the drying process difficult. Therefore, the drying of modified wood is challenging. This study focuses on poplar wood and reports the preparation of modified wood capable of releasing health-beneficial negative oxygen ions. In particular, this study examined the effect of hexacyclite on the transfer of internal moisture and heat in wood. Hexacyclite was dispersed using sodium hexametaphosphate as a dispersing agent, and the modified poplar wood was prepared via vacuum pressure impregnation. The process involved six cycles of the following treatments: a vacuum treatment (−0.08 MPa, 20 min), followed by a pressure treatment (1 MPa, 120 min), and a final atmospheric treatment (5 min). The modified wood was dried via kiln drying, during which the overall wood temperature rapidly increased, with the total drying rate also increasing by 1.05%/h. The introduction of hexacyclite potentially altered the way modified wood bound with moisture, leading to permanent changes in the porosity of cell walls and the structure of polymers and thus altering the movement of water molecules. The modified wood continuously emitted far-infrared rays with a wavelength of 8–15 μm. In some large water clusters, after the far-infrared energy was absorbed, the movement of water molecules accelerated, thereby increasing the drying rate in the wood below the fiber saturation point. Ultimately, this resulted in the modified wood drying faster and thus exhibiting a better quality. [ABSTRACT FROM AUTHOR]

The increasing global commitment to carbon neutrality has propelled a heightened focus on sustainable construction materials, with wood emerging as pivotal due to its environmental benefits. This review explores the development and application of eco-friendly polymer nanocomposite coatings to enhance wood's fire resistance, addressing a critical limitation in its widespread adoption. These nanocomposites demonstrate improved thermal stability and char formation properties by integrating nanoparticles, such as nano-clays, graphene oxide, and metal oxides, into biopolymer matrices. This significantly mitigates the flammability of wood substrates, creating a robust barrier against heat and oxygen. The review provides a comprehensive examination of these advanced coatings' synthesis, characterization, and performance. By emphasizing recent innovations and outlining future research directions, this review underscores the potential of eco-friendly polymer nanocomposite coatings as next-generation fire retardants. This advancement supports the expanded utilization of wood in sustainable construction practices and aligns with global initiatives toward achieving carbon neutrality. [ABSTRACT FROM AUTHOR]

The synergetic strategy has created tremendous advantages in drug-resistance bacterial infection treatment, whereas challenges related to novel compound discovery and identifying drug-binding targets still remain. The mechanisms of antimicrobial resistance involving β-lactamase catalysis and the degradation of β-lactam antibiotics are being revealed, with relevant therapies promising to improve the efficacy of existing major classes of antibiotics in the foreseeable future. In this study, it is demonstrated that nordalbergin, a coumarin isolated from the wood bark of Dalbergia sissoo, efficiently potentiated the activities of β-lactam antibiotics against methicillin-resistant Staphylococcus aureus (MRSA) by suppressing β-lactamase performance and improving the bacterial biofilm susceptibility to antibiotics. Nordalbergin was found to destabilize the cell membrane and promote its permeabilization. Moreover, nordalbergin efficiently improved the therapeutic efficacy of amoxicillin against MRSA pneumonia in mice, as supported by the lower bacterial load, attenuated pathological damage, and decreased inflammation level. These results demonstrate that nordalbergin might be a promising synergist of amoxicillin against MRSA infections. This study provided a new approach for developing potentiators for β-lactam antibiotics against MRSA infections. [ABSTRACT FROM AUTHOR]

While the succession of terrestrial plant communities is well studied, less is known about succession on dead wood, especially how it is affected by environmental factors. While temperate forests face increasing canopy mortality, which causes considerable changes in microclimates, it remains unclear how canopy openness affects fungal succession. Here, we used a large real-world experiment to study the effect of closed and opened canopy on treatment-based alpha and beta fungal fruiting diversity. We found increasing diversity in early and decreasing diversity at later stages of succession under both canopies, with a stronger decrease under open canopies. However, the slopes of the diversity versus time relationships did not differ significantly between canopy treatments. The community dissimilarity remained mainly stable between canopies at ca. 25% of species exclusively associated with either canopy treatment. Species exclusive in either canopy treatment showed very low number of occupied objects compared to species occurring in both treatments. Our study showed that canopy loss subtly affected fungal fruiting succession on dead wood, suggesting that most species in the local species pool are specialized or can tolerate variable conditions. Our study indicates that the fruiting of the fungal community on dead wood is resilient against the predicted increase in canopy loss in temperate forests. [ABSTRACT FROM AUTHOR]

In this work, levulinic acid (LLA) was used as a new bio-based solvent for solvolysis liquefaction of wood under mild conditions (temperature 160 ± 5 °C and atmospheric pressure). The liquefaction of sugar maple (Acer saccharum Marsh.) wood at a high rate (up to 93%) was obtained under these conditions. The liquefied product was divided into water-insoluble (WILW) and water-soluble (LArF) fractions. LArFs were mixtures of low-molecular weight compounds including unreacted LLA and furfuryl alcohol, as shown by electrospray ionization-mass spectrometry (ESI–MS) analysis. WILW has shown a high acid number (205–211 mg KOH/g) and a low hydroxyl number (< 23 mg KOH/g), which is in contrast with the conventional hydroxylated liquefied products reported in the literature so far. WILW was cured with LArF, a glycerol-liquefied wood, hexamine, and methylene diphenyl diisocyanate for the preparation of wood coatings. Cured coatings showed good pull-off adhesion strengths to the surface of beech wood, resistance to water, and low ΔE* color change when exposed to ultra-violet (UV) light. Liquefying wood in LLA provides a reactive product containing carboxylic acid groups that could be used to produce cleaner, petroleum-free materials. [ABSTRACT FROM AUTHOR]

Water interactions with cellulose, hemicellulose, and lignin in cell walls significantly influence their dimensional properties and thus the many applications of wood and other cellulosic materials. The sustainable development and application of wood and cellulosic materials require a better understanding of the mechanisms involved in the deformation with moisture changes. The dimensional changes of multiscale structures of Masson pine were studied during moisture desorption, and the differences at different scales were compared. The confocal laser scanning microscopy (CLSM) was used to observe the deformation of cells. The detail of wood nanostructure was characterized by small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS). The molecular interaction between moisture and cell wall was studied using Fourier-transform infrared (FTIR). The results revealed that weakly hydrogen-bonded water molecules and water molecule clusters desorbed from the wood cell walls during moisture loss. The loss of water molecules altered the wood nanostructure, resulting in 12% and 7% reductions in the distances between the elementary fibrils in the latewood (LW) and earlywood (EW) cell walls, respectively. The dimensions of the cellulose crystallites in LW and EW decreased by 5% and 2%, respectively. At the cellular level, the tangential shrinkage of LW and EW were 9% and 6%, respectively. The reduction of the shrinkage at the larger scale can be attributed to the mutual inhibition and fine-tuning of the multi-scale hierarchical structures in wood. These findings provide insight into the instability of wood or natural cellulosic materials during moisture desorption and contribute to developing of more targeted wood-based materials. [ABSTRACT FROM AUTHOR]

Wood constitutes a unique and valuable material that has been used from ancient times until nowadays in a wide variety of applications, in which the surface quality of wood often constitutes a critical factor. In this study, the influence of different wood areas and therefore, of different anatomical characteristic areas of chestnut wood (Castanea sativa Mill.) on the surface quality, was thoroughly studied, in terms of surface roughness. Five different chestnut tree trunks were harvested, from which five different disks were obtained corresponding to five different trunk heights. Surface roughness was measured on these disks on the transverse, radial, and tangential planes, on the areas of sapwood and heartwood, measuring the roughness in each point both vertically and in parallel to the wood grain. The results revealed that the examined roughness indexes (Ra, Rz, Rq) follow a parallel path to one another. In the case of all surfaces (transverse, radial, tangential) of the disks examined, when the measurement was implemented perpendicularly to the wood grain, a significantly higher roughness was recorded, compared to the wood grain measurements being implemented in parallel with the wood grain. Significant differences between heartwood and sapwood roughness were not demonstrated, although sapwood often appeared to exhibit a higher surface roughness than heartwood sites. Among the roughness values of the three different surfaces, the highest roughness in the vertical-to-wood-grain measurements was recorded by tangential surfaces, with slightly lower values on the transverse surfaces and the lowest roughness on radial surfaces. Meanwhile, for the measurements in parallel with the wood grain, the transverse surfaces presented significantly higher roughness values compared to the tangential and radial surfaces. Significant roughness differences were not detected among the surfaces at different trunk heights. Although, significant differences in roughness were recorded among different trees, it was observed that all the studied trees align with the identified and described within-tree trends. [ABSTRACT FROM AUTHOR]

As the construction industry places increasing emphasis on environmental conservation and sustainability, this trend has spurred profound research into the optimization of door and window performance. One of the critical components of windows is their frames. Over the past several decades, the design of window frames has undergone significant innovations, ranging from introducing new materials to novel design concepts. The performance of window frames is typically influenced by materials, structural design, and the surrounding environment. Consequently, this paper analyzes the common window frame materials in Chinese civil buildings through investigation. It explores commonly used types of window frames available in the market, focusing on their materials and structural designs. It analyzes issues observed during their usage, integrates findings from existing research, and discusses the performance of window frame materials. Additionally, it explores improvement strategies to meet the evolving demands of contemporary and future architectural doors and windows, providing valuable reference points for designers. Finally, approaching the discussion from a sustainable development perspective, the paper evaluates the environmental impact of wood, aluminum alloy, polymer, and composite window frame materials. It emphasizes that wood- and aluminum-clad wood windows represent sustainable options with versatile applications in diverse scenarios. [ABSTRACT FROM AUTHOR]

Introduction: Global illegal trade in timbers is a major cause of the loss of tree species diversity. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) has been developed to combat the illegal international timber trade. Its implementation relies on accurate wood identification techniques for field screening. However, meeting the demand for timber field screening at the species level using the traditional wood identification method depending on wood anatomy is complicated, time-consuming, and challenging for enforcement officials who did not major in wood science. Methods: This study constructed a CITES-28 macroscopic image dataset, including 9,437 original images of 279 xylarium wood specimens from 14 CITES-listed commonly traded tree species and 14 look-alike species. We evaluated a suitable wood image preprocessing method and developed a highly effective computer vision classification model, SE-ResNet, on the enhanced image dataset. The model incorporated attention mechanism modules [squeeze-and-excitation networks (SENet)] into a convolutional neural network (ResNet) to identify 28 wood species. Results: The results showed that the SE-ResNet model achieved a remarkable 99.65% accuracy. Additionally, image cropping and rotation were proven effective image preprocessing methods for data enhancement. This study also conducted real-world identification using images of new specimens from the timber market to test the model and achieved 82.3% accuracy. Conclusion: This study presents a convolutional neural network model coupled with the SENet module to discriminate CITES-listed species with their look-alikes and investigates a standard guideline for enhancing wood transverse image data, providing a practical computer vision method tool to protect endangered tree species and highlighting its substantial potential for CITES implementation. [ABSTRACT FROM AUTHOR]

This study aimed to investigate and compare the non-anatomical characteristics of six Korean oak wood species (Quercus variabilis, Q. serrata, Q. mongolica, Q. dentata, Q. aliena and Q. acutissima) to provide identification keys and quality indices for the effective utilization of these species. Non-anatomical characteristics, including heartwood fluorescence, fluorescence and color of water and ethanol extracts, froth test, chrome azurol S test and burning splinter test, were evaluated according to the International Association of Wood Anatomists (IAWA) lists. None of the six Korean oak species displayed heartwood fluorescence or fluorescence in the ethanol extract. Only Q. serrata exhibited bright blue fluorescence in the aqueous extract. Each species showed distinct colors in both water and ethanol extracts, and the water extract of all species was darker than that of the ethanol extract. A weak positive reaction in the froth test was observed only for Q. serrata. Furthermore, Q. variabilis and Q. acutissima showed positive reactions to both heartwood and sapwood in the chrome azurol S test. The burning splinter test revealed that only Q. acutissima was transformed into charcoal. Thus, water extract fluorescence and color, ethanol extract color, froth test, chrome azurol S test, and burning splinter test can be used to identify the six Korean oak species. [ABSTRACT FROM AUTHOR]

The manufactured capital, usually denoted as material stocks from an industrial ecology perspective, has thus far received wide attention in sustainability and circularity science. Sustainable resource management should be rooted in detailed knowledge of manufactured capital accumulation in society at a high spatial resolution. Previous studies demonstrated that night‐time light (NTL) data provide a great opportunity for monitoring material stocks dynamics at a higher spatial resolution on the regional and global scale. However, the potential of historical–geographical refined material stocks has not been fully analyzed and explored because of the inconsistency of NTL images detected by the different satellites. In this study, based on a new set of material stocks data in China and harmonized NTL images (1992–2018), we map the national stocks of 13 bulk materials (including cement, gravel, wood, brick, sand, asphalt, glass, lime, plastic, rubber, copper, aluminum, and steel) at a 1 × 1 km resolution from 1992 to 2018. The results find that the total material stocks increased from 190,000 to 460,000 t/km2 between 1992 and 2018. Among the five end‐use sectors, buildings have the highest density of 430,000 t/km2, while domestic appliances have the lowest density of 140 t/km2. Four manufactured capital clusters, including the Yangtze River Delta, Pearl River Delta, Beijing–Tianjin–Hebei, and Chengdu–Chongqing agglomerations, possess 38% of the national total stocks in 2018, revealing an unbalanced distributed pattern of manufactured capital across China. Our results provide valuable support for policymakers and business decision‐makers on efficient resource management and urban mining. [ABSTRACT FROM AUTHOR]

The effects of timber harvest practices and climate change have altered forest ecosystems in southeast Alaska. However, quantification of patterns and trends in stream habitats associated with these forests is limited owing to a paucity of data available in remote watersheds. Here, we analyzed a 30-year dataset from southeast Alaska's Tongass National Forest to understand how these factors shape stream habitats. First, we examined differences between broad management classes (i.e., harvested and non-harvested) that have been used to guide stream channel restoration goals. Second, we assessed associations between intrinsic landscape characteristics, watershed management, and timber harvest legacies on aquatic habitat metrics. And third, we examined trends in stream habitat metrics over the duration of the dataset to anticipate future management challenges for these systems. Small effect sizes for some harvest-related predictors suggest that some stream habitat metrics, such as pool densities, are less responsive than others, and management practices such as protecting riparian buffers as well as post-harvest restoration may help conserve fish habitats. Large wood densities increased with time since harvest at sites harvested >50 years ago, indicating that multiple decades of post-harvest forest regrowth may contribute large wood to streams (possibly alder), but that it is not enough time for old-growth trees (e.g., spruce, Picea, or hemlock, Tsuga,), classified as key wood, to develop and be delivered to streams. The declining trend in key wood (i.e., the largest size class of wood) regardless of management history may reflect that pre-harvest legacy old-growth trees are declining along streams, with low replacement. The introduction of wood to maintain complex stream habitats may fill this gap until riparian stands again contribute structural key wood to streams. Trend analyses indicate an increasing spatial extent of undercut banks that may also be influenced by shifting hydrologic regimes under climate change. [ABSTRACT FROM AUTHOR]

Nanocellulose extraction from lignocellulosic materials is a highly chemical and energy‐intensive process as it requires the removal of lignin and hemicellulose. Writing paper is one of the processed materials that could be used as a raw material for the extraction of nanocellulose. In this work, cellulose nanofibers (CNFs) were synthesized from paper waste using TEMPO‐oxidation followed by high‐shear microfluidization. Scanning electron microscopy and atomic force microscopy confirmed the diameter of fibers in the nano‐range and a consistent zeta potential confirmed the stability of CNF suspension in water over a long time frame. Characterization of the CNFs using Fourier transform infrared spectroscopy indicated the presence of a carbonyl group due to the oxidation process. Thermogravimetric analysis and x‐ray diffraction revealed lower thermal stability and reduction in the crystallinity index of CNFs, as compared to pulp fibers. The obtained CNFs were used successfully as the sole binding agent in the preparation of fiberboards and also utilized as a reinforcing agent for polyvinyl acetate (PVAc) adhesive in the preparation of laminated veneer lumber (LVLs). The addition of CNFs in PVAc improved the glue shear strength indicating superior bonding characteristics and also increased the water resistance of the LVLs. Highlights: This work focused on cellulose nanofibers (CNFs) extraction from waste paperObtained CNFs form stable water suspension and have a diameter of less than 15 nmThermal stability and crystallinity index reduced after conversion to nanofibersCNFs form a complex network and act as a sole binder to make fiberboardsCNFs were utilized as a reinforcing agent for PVAc in preparation of LVLs [ABSTRACT FROM AUTHOR]

In this research, microblasting with powdered vegetable particles (almond and hazelnut husks, cork saw dust and rice husks) and cellulosic fibres was used to analyse their usefulness for cleaning unpainted wooden cultural heritage and their effects on surface morphology. Tests were made on mock-ups of old pine wood from wooden boards with original soiling. Before cleaning powdered particles were characterised by SEM–EDS to analyse their morphology and elemental composition. Wood surfaces were analysed before and after cleaning by means of digital microscope (white and UV light) and SEM–EDS to evaluate cleaning effectiveness, assess effects on the wood surface, and determine eventual soiling and powdered particles larger than 1 µm that might remain in the surface after the procedure. Results indicate that microblasting with powdered vegetable and cellulosic media is a useful and safe technique to remove soiling from wood, including micrometric particles embedded in its texture, with negligible surface changes. Furthermore, residues left after the cleaning procedure are very scarce and chemically compatible with the substrate because they are mainly composed of cellulose, hemicellulose and lignin, the main components of wood. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to fabricating interdigitated capacitive (IDC) touch sensors using graphite-based pencils on a wood substrate. The sensors were designed to detect touches and pressure variations, offering a cost-effective and environmentally friendly solution for sensor fabrication. The fabrication process involved abrasion of graphite pencils on a wooden substrate to create conductive traces, followed by the integration of interdigitated electrode structures. Capacitance variations resulting from touch interactions were investigated to calibrate sensor responses for tailored tasks. The sensitivity of the sensor was found to be 1.2 pF/kPa, highlighting its responsiveness to pressure variations. Additionally, the sensors were interfaced with an Arduino Uno microcontroller board to demonstrate practical applications, such as replicating arrow key functionality. Additionally, the sensors exhibit sensitivity to environmental factors, with the relative change in capacitance increasing from 0.1 to 0.65 as relative humidity ranges from 30 to 90%. Furthermore, variations in temperature from 30 to 60ºC result in a relative change in capacitance increasing to approximately 0.5. The results indicate the feasibility and versatility of using wood-based substrates and graphite-based pencils for fabricating IDC touch sensors, offering promising prospects for sustainable and accessible sensor technology. [ABSTRACT FROM AUTHOR]

Background: Drought periods are major evolutionary triggers of wood anatomical adaptive variation in Lower Tropical Montane Cloud Forests tree species. We tested the influence of historical drought events on the effects of ecological stress memory on latewood width and xylem vessel traits in two relict hickory species (Carya palmeri and Carya myristiciformis) from central-eastern Mexico. We hypothesized that latewood width would decrease during historical drought years, establishing correlations between growth and water stress conditions, and that moisture deficit during past tree growth between successive drought events, would impact on wood anatomical features. We analyzed latewood anatomical traits that developed during historical drought and pre- and post-drought years in both species. Results: We found that repeated periods of hydric stress left climatic signatures for annual latewood growth and xylem vessel traits that are essential for hydric adaptation in tropical montane hickory species. Conclusions: Our results demonstrate the existence of cause‒effect relationships in wood anatomical architecture and highlight the ecological stress memory linked with historical drought events. Thus, combined time-series analysis of latewood width and xylem vessel traits is a powerful tool for understanding the ecological behavior of hickory species. [ABSTRACT FROM AUTHOR]

Perennial trees have a recurring annual cycle of wood formation in response to environmental fluctuations. However, the precise molecular mechanisms that regulate the seasonal formation of wood remain poorly understood. Our prior study indicates that VCM1 and VCM2 play a vital role in regulating the activity of the vascular cambium by controlling the auxin homoeostasis of the cambium zone in Populus. This study indicates that abscisic acid (ABA) affects the expression of VCM1 and VCM2, which display seasonal fluctuations in relation to photoperiod changes. ABA‐responsive transcription factors AREB4 and AREB13, which are predominantly expressed in stem secondary vascular tissue, bind to VCM1 and VCM2 promoters to induce their expression. Seasonal changes in the photoperiod affect the ABA amount, which is linked to auxin‐regulated cambium activity via the functions of VCM1 and VCM2. Thus, the study reveals that AREB4/AREB13‐VCM1/VCM2‐PIN5b acts as a molecular module connecting ABA and auxin signals to control vascular cambium activity in seasonal wood formation. [ABSTRACT FROM AUTHOR]

Symbionts form intricate associations with their hosts. They can only establish when potential hosts are present, but in addition, their distribution is often influenced by microhabitat preferences, which may not overlap those of their hosts. This leads to a patchy local distribution of the symbiont, being present with some hosts and absent with others. We studied this effect of microhabitat preferences on symbiont distribution by examining the occurrence and density of the obligately ant‐associated springtail Cyphoderus albinus Nicolet (Collembola: Paronellidae) across a mosaic of ant nests. Nest structure strongly varied both within and between ant species and included sand, dead wood, arboreal and thatch mound nests. We hypothesized that the symbiotic springtail would show the strongest preference for thermoregulated and organic‐rich nests such as thatch mounds. The springtail was found in all thatch mound nests of red wood ants and in all arboreal nests of Lasius fuliginosus (Latreille). A high occurrence (75%) was recorded in the smaller thatch nests of Formica sanguinea Latreille. Lasius, Myrmica and Formica species exhibited variation in nest structures on the ground, establishing nests in both sand and wood. For each of these three host taxa, encountering the springtail was more likely in their wood nests (medium‐to‐high occurrence), than in their sand nests where the occurrence was low. Nest structure did not only impact springtail occurrence, but their densities as well. The densities within thatch nests were much higher than those in other nest types, achieving the highest densities (1148 individuals per litre of nest material) observed for a social insect symbiont. Our findings emphasize that host nests with wood structures and thatch material provide a more favourable habitat for the springtail compared with soil nests. Overall, this study underscores the role of microhabitat variation in the spatial distribution and density of a symbiotic species. [ABSTRACT FROM AUTHOR]

The preparation of mechanical robust organic room‐temperature phosphorescence (RTP) materials especially with white afterglow is attractive but rarely reported. Herein, a method to produce mechanical robust colorful RTP transparent wood (PTW) by infiltrating delignified wood with poly (vinyl alcohol) solutions containing arylboronic acids with various π conjugations is reported. The doubly rigid environment provided by the B─O covalent bonds and hydrogen bonds can stabilize the triplet excitons, leading to a ultralong lifetime of up to 2.13 s and excellent RTP emission stability (without obviously quenching over a month) of the target PTW. Besides, as a promising structural material for optical applications, the PTW shows combined advantages of multicolored persistent luminescence (from blue to green and then to red), good optical transmittance (≈90%), and striking mechanical strength (≈154 MPa). More importantly, by introducing appropriate amount of fluorescent dye rhodamine 6 G to the PTW with blue afterglow, white afterglow with a lifetime of 1.85 s is successfully achieve through triplet‐to‐singlet Förster resonance energy transfer. The PTW can function as afterglow window, anticounterfeiting label, and time delay lighting. This success paves the way for the development of mechanical robust, ecofriendly, and practical RTP materials. [ABSTRACT FROM AUTHOR]

Agropastoral practices that historically reduced the flammability of Mediterranean landscapes are poorly understood due to state prohibitions and lack of scientific interest. Oral histories, analysis of agronomical writings, transect walks, and ethnographic study of fire managers and community members in the Monte Pisano of Italy, find legacies of traditional agropastoral practices in present-day landscapes. Forest leaf litter raking, largely carried out by women, combined with fire wood cutting and burning to greatly reduce fire risk. Historic stigmatization of traditional burning and ignoring gendered peasant labor have reduced contemporary scientists' and fire managers' understandings of ecological processes and of options for reducing fire risk. Fire managers in the Mediterranean, and in areas around the world affected by rural depopulation, would benefit from a better understanding of traditional agropastoral and fire management practices. Litter raking has been understudied outside Central Europe, is often gendered, and may have important ecological consequences around the world. [ABSTRACT FROM AUTHOR]

Recent global market disruptions, including the COVID-19 crisis, inflation, and oil crises, have highlighted the need for industries to reduce dependence on petrochemicals. However, the coating industry remains reliant on petrochemicals due to a lack of knowledge about local and sustainable alternatives. This study explored the potential of wood extractives as precursors for producing high-quality wood coatings. Terpenes were modified through acrylation, and bio-based latexes were synthesized from these modified terpenes. Analysis showed that all tested latexes had conversion levels above 88.5%. The bio-based films were characterized, and their transparency, measured by ultraviolet-visible spectroscopy, exceeded 80%. The good incorporation of bio-based monomers in the latex films was confirmed by thermogravimetric analysis and pyrolysis-gas chromatography-mass spectrometry. Comparative analysis between bio-based and conventional latexes showed equivalent results in particle size, molecular weight, glass transition temperature, and minimum film formation temperature. However, bio-based films exhibited lower hardness. The study suggests that using monomers derived from wood extractives offers a viable alternative to petrochemicals, utilizing abundant forest residues. This approach could address raw material shortages and help make the coatings industry more sustainable by reducing its reliance on petrochemicals. [ABSTRACT FROM AUTHOR]

Wood specimens were dyed by boiling them in the presence of walnut shells and dye to penetrate the dyestuff into the sample. Specimens prepared from Scots pine, oak, and beech woods were boiled separately in walnut shell, water, and NaOH environment, and the penetration of the dyestuff into the samples was ensured. Sodium hydroxide solution was preferred because it facilitates the dissolution of the hemicelluloses in the wood and the dyestuffs in the walnut shell. Alum was added in other samples to reveal the mordant effect on the adhesion of dyestuffs to wood. Thermogravimetric (TG) analysis revealed that wood degradation primarily occurs due to evaporation of free water at 50 to 120 ℃, followed by lignin and cellulose breakdown across a wide temperature range of 160 to 600 ℃. Treatment with NaOH and NaOH+alum notably reduced the peak temperatures in differential-thermogravimetric analysis by indicating an effect on lignin. This was supported by Fourier transform infrared analysis, particularly in the disappearance of carboxyl groups at 1710 cm-1 and significant decreases in peak intensities at 1027, 1247, 1315, and 1501 cm-1. Based on the findings, it was concluded that the dyed parts obtained can be used in the wooden toy industry. [ABSTRACT FROM AUTHOR]

Efficient utilization of wood is inseparable from high-quality drying, and analysis of its free shrinkage performance is essential to optimize the drying process. This study took Pinus sylvestris L. sawn timber (500 mm ×200 mm×50 mm) as the research object and adopted the image analysis method to analyze the influence rules of different temperatures and axial positions of the test material on the free dry shrinkage coefficient of each layer of specimens in the thickness direction. The free shrinkage coefficients of each layer in the thickness direction of the test material decreased from the maximum value of the first layer near the tangential direction (0.282%, 0.275%, 0.267%, at 60 ℃, 80 ℃, and 100 ℃, respectively) to the minimum value of the ninth layer near the radial direction (0.248%, 0.249%, 0.227%); except for the near-radial layers, when temperature increased from 60 ℃ to 100 ℃ the free shrinkage coefficients of other representative layers decreased with increased temperature. The first layer's free shrinkage coefficient decreased from 0.282% to 0.267%, and the fifth layer decreased from 0.264% to 0.243%. The difference of free shrinkage coefficients between corresponding layers at different axial positions of the test material was less than 0.017%, and the size stability of the corresponding layers at axial positions was high. [ABSTRACT FROM AUTHOR]

The clonal materials of Tectona grandis L. f. in fast-growing plantations exhibit faster growth than the seminal materials. Therefore, it is necessary to investigate the differences in wood drying to ensure the quality and yield of the final product. This study evaluated the outdoor drying behavior of three genotypes of teak lumber. Two clonal genotypes (G1 and G2) and one of seminal origin (G3) were assessed. Boards measuring 30 × 150 × 1000 mm (thickness × width × length) were produced from the basal logs. The average moisture content (79.3, 64.9, and 60,1%), final moisture content (10.8, 9.8, and 11.6%), and mean drying rate (1.2, 0.97, and 0.85%.day-1) were observed in the wood from genotypes G1, G2 and G3, respectively. The clonal material crooked and bowed below 5 mm.m-1, which is considered the tolerance limit for both warpings. The seminal material had a greater incidence of splitting. The clonal genotypes G1 and G2 had similar qualities and presented higher drying rates, final moisture contents below 11% and a lower incidence of defects, especially splitting, compared to the naturally seeded material. [ABSTRACT FROM AUTHOR]

Wood fiber insulation (WFI) was studied as an eco-friendly alternative for fossil-based building insulation, focusing on its use in new wood fiberinsulated panels (WIPs). Rigid WFI boards with densities of 110, 140, and 180 kg/m³, including a 140 kg/m³ variant without paraffin wax, were evaluated. Key properties investigated included porosity, water vapor transmission, liquid water adsorption, and thermal conductivity. The porosity ranged between 85 and 92%, primarily influenced by density. Water vapor permeability ranged from 65 to 90 ng·s-1m-1Pa-1, while liquid water absorption was between 2.5 and 20% by volume, influenced by both wax and density. The thermal conductivity coefficient ranged from 0.038 to 0.055 W/(m·K). Bond strength tests with WFI (140 kg/m³ with wax) laminated to various materials using structural adhesives showed tensile perpendicular-to-grain strengths of 10 to 16 kPa and shear strengths of 60 to 90 kPa, with failure only occurring within the WFI. It was concluded that WFI is a promising material for novel WIPs, offering competitive hygrothermal properties and compatibility with structural adhesives. However, its bio-based nature suggests variability and complexity, necessitating further rigorous testing in various climates and in more complex assemblies. [ABSTRACT FROM AUTHOR]

Thermal modification processes are environmentally friendly methods used to improve certain properties of wood. Currently, wood from thinning of young plantations of Nothofagus alpina (raulí) in Chile is being evaluated to obtain value before the plantation has reached maturity. The objective of this paper was to assess selected properties of thermally modified wood of young (14- to 25-years-old) N. alpina wood that comes from thinning of two sites with intensive silviculture and one similar to a secondary growth forest. To achieve this, non-destructive tests were carried out to measure some chemical-crystalline characteristics, as well as physical and mechanical properties; the differences between the 25%, 50%, and 75% distance from pith to the bark in each site was studied. The modification temperatures used were 170, 190, and 210 ℃. The results show that thinning wood from N. alpina can be thermally modified with favorable results, thus presenting an option to obtain value while the plantation reaches maturity, particularly the thinning wood from the intensive forestry regimes, which presented most homogeneous results, especially at the modification temperature of 190 ℃. [ABSTRACT FROM AUTHOR]

The bordered pitting arrangements in the tracheids of Dahurian larch (DL) and Japanese larch (JL) growing in Korea were studied using optical microscopy to gain insights into the wood identification of both species. Differences were noted in the tracheid pitting patterns between the species. In juvenile wood, DL dominantly exhibited uniseriate pitting along the earlywood within a growth ring, whereas JL displayed biseriate pitting at the start of the earlywood, transitioning to uniseriate pitting. In the transition wood, DL predominantly showed biseriate pitting at the beginning, with uniseriate pitting at the end, while JL exhibited uniseriate pitting initially and at the end, with biseriate pitting in the middle. The mature wood of both species predominantly exhibited a biseriate pitting arrangement with a few uniseriate pitting at the end of the earlywood. JL exhibited a higher proportion of biseriate pitting than DL. The proportion of biseriate pitting and radial tracheid width in both species increased with increasing growth ring number, showing a positive correlation. While some differences were found between DL and JL, further investigation is needed to evaluate the consistency and practical applicability of pit patterns for wood identification in diverse field conditions. [ABSTRACT FROM AUTHOR]