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In recent years, ancient wooden building fires have been a hot issue that has not been properly solved. The existing ancient wood buildings objectively have serious natural ageing phenomenon, among which the dry and wet alternating ageing phenomenon of wood caused by water is the most serious. However, the phenomenon of dry and wet alternating ageing pays less attention to the influence of wood combustion. Therefore, this study took the typical wood species of ancient wooden buildings as the research object, based upon the natural ageing phenomenon of these buildings, determining the artificial acceleration of dry and wet alternate ageing method, to obtain dry and wet alternate ageing wood. The thermal diffusion coefficient of dry and wet ageing wood was analysed by thermal property experiments. Using differential scanning calorimetry experiment, we appraised the change law of heat flow in the combustion process of dry and wet ageing wood, determined the characteristic peak intensity and stage continuous temperature of dry and wet ageing wood, and mastered the change characteristics of wood in different thermal release stages affected by dry and wet alternating ageing. Finally, the apparent activation energy distribution of ageing wood in different exothermic stages was calculated and analysed by isoconversion method. The influence mechanism of alternating dry and wet ageing on wood combustion thermal release behaviour was revealed. The results show that the main thermal release of dry–wet ageing is the stage of volatiles precipitation. The alternate ageing of dry and wet has the greatest impact on the energy demand of thermal response in the accelerated thermal release stage. The influence of alternating dry and wet ageing on different types of wood in the rapid exothermic stage is quite different. [ABSTRACT FROM AUTHOR]

The study explored the post-wildfire elemental composition of parts (wood, bark, branch, cone, trunk, litter, twig, needle, sward, fallow, sapling, etc.) and by-products (biomass ashes, partly burnt parts, and char) of different woody species in the Bohemian Switzerland National Park, Czech Republic, and considered their effects on soils. Multi-elemental analysis of the fire by-products of the woody species was determined with inductively coupled plasma-optical emission spectrometry and mass spectrometry and compared with control biomass samples unaffected by wildfire. Most fire by-products were slightly alkaline, with acidic ashes obtained from blueberry wood. The by-products of the wildfire were characterized by varied total contents of macro (P, Ca, K, Mg, and S), micro (Na, Mn, Fe, Cu, and Zn), and other elements (B, Co, Mo, and V) vital to soil fertility and plant growth. The mean content of macro elements in the biomass ashes was up to 4.16 P, 23.5 Ca, 2.48 Mg, 63 K, and 5.57 S g kg−1. These values were comparatively lower than published data for ashes obtained under optimized conditions, e.g., those combusted in power generation facilities. Conversely, partly burnt parts—an indication of incomplete combustion—had higher 9.22 P, 79 Ca, and 5.99 Mg g kg−1 contents in spruce needles than in biomass ashes and the control. Variations in woody species and anthropogenic activities in areas of wildfires produced varied As, Cd, Cr, Ni, and Pb contents above EU fertilizer regulation. Caution in applying biomass ashes from wildfires on fields is required due to risk/toxic elements input from anthropogenic activities. Wildfire effects on the elemental composition of woody species can provide information on plant parts most suitable for biomass ashes for soil and ecosystem safety. [ABSTRACT FROM AUTHOR]

Sextonia rubra is an Amazonian tree known for the larvicide activity of its wood extracts against Aedes aegypti. However, the lipophilic character of this extract presents an obstacle to the development of vector management products. The purpose of this study was to assess the feasibility, efficacy, and selectivity of a water-soluble formulation based on a S. rubra wood extract characterized by its larvicidal compounds rubrenolide and rubrynolide. Using reference and wild strains, larval mortality, oviposition behavior, hatching response, and fitness of mosquitoes exposed to the extract were evaluated. Laboratory eco- and cytotoxicity bioassays were performed concurrently. The extract showed larvicidal efficacy and no repulsive effect on oviposition, thus supporting its use in the treatment of breeding sites. The formulation exhibited strong acute toxicity, leading to 100% larval mortality in 2–4 days in either the dry or rainy season at a test dose of 102 µg/ml under semi-operational conditions, with residual activity maintained during the 5 weeks of testing. The formulation allowed for a noticeable gain in selectivity compared with the extract, with lower immobilization rates for Daphnia magna and Chironomus riparius, and no significant toxicity towards human cell lines (IC50 > 100 µg/ml). These results highlight the potential of the S. rubra-based formulation for the management of Ae. aegypti larvae, including strains showing resistance to conventional insecticides. [ABSTRACT FROM AUTHOR]

Herein, we successfully modified wood sponge (WS) with Fe3O4 (MWS) to enhance its ability to adsorb five different oils, eight organic solvents, metal ions, and degrade methylene blue (MB) from wastewater. MWS, possessing over 96% porosity, exhibited remarkable sorption capacities of 26.79 g g− 1 for CCl4 and 21.00 g g− 1 for pump oil. Notably, MWS maintained high sorption capacity even after repeated use. Furthermore, MWS effectively removed toxic metal ions including As3+, Cr6+, and Pb2+ from real industrial wastewater, at pH 4 and 50 °C to levels suitable for drinking water. Also, MWS demonstrated excellent photocatalytic properties for degrading methylene blue dye. The photodegradation process involved the generation of superoxide anion radicals and the participation of hydroxyl radicals. The magnetic properties of MWS allow for easy remote retrieval using a magnet, making it a cost-effective and reusable solution for environmental remediation. [ABSTRACT FROM AUTHOR]

The study investigates the horizontal fuel size effect on free-burning fires for PMMA plates and wood cribs. The fuel size effect on mass burning flux and flame behavior is mainly discussed and compared with typical pool fires. For the PMMA plate and liquid pool, when the fuel size is small (< 10 cm), either the 3D sidewall burning of PMMA or the container wall heated by flame can promote the burning flux at the horizontal projection area. As the fuel size increases, these side wall burning or heating effects decrease, causing the drop in burning flux with fuel scale for both the PMMA plate and liquid pool. For small-scale wood cribs, fire cannot self-sustain due to the large airflow cooling. With the increase in wood crib size, the burning rate first remains constant and then gradually increases, driven by the enhanced internal radiation. As the fuel size increases above 20–30 cm, the flame radiation dominates the burning flux for all fuel types. Fire dynamics simulator (FDS) was adopted to simulate the horizontal size effect by setting a varied fire source (horizontal projection) area. First, the flame geometry and heat release rate (HRR) of simulations were validated against experimental results. Subsequently, the validated fire model generates cases covering a broad range of fire scales. Finally, a new correlation of flame height with the fire heat release rate and fuel size is proposed, and its prediction capability is validated in the numerical fire modeling. This study quantifies the size effect on the burning rate for common solid fuels and provides valuable information for the numerical modeling of multi-scale fires. [ABSTRACT FROM AUTHOR]

In the present study, with a view to decreasing the inherent fire risk associated with the usage of wood, the flame-retardant efficacies of some additives for wood samples were investigated. The additives included: 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), triphenylphosphine (TPP), diammonium hydrogen phosphate ((NH4)2HPO4) and sodium carbonate (Na2CO3). The test samples incorporating the flame-retardant additives were primarily evaluated by thermo-gravimetric analysis (TGA). It was found that the presence of DOPO imparted some beneficial effects, especially, in terms of increased energetic needs for the second-stage decomposition of the lingo-cellulosic material, coupled to an enhanced production of char residues. However, with the other additive systems, such as TPP, Na2CO3 and (NH4)2HPO4, the flame-retardant effect seemed to arise from increased char production with a concomitant effect on the energetic requirements for the decomposition pathways, especially, at a high temperature. In terms of to the conversion degrees, for samples PFC2, PFC3 and PFC4, stage one was found to extend over the conversion range of 0 ≤ α ≤ 0.65, corresponding to temperatures from 30 to 350 °C. In contrast, for samples PFC5, PFC6 and PFC7, stage one seemed to span over a conversion range of 0 ≤ α ≤0.55, during the same temperature range. Additionally, PFC2 exhibited maximum char residue, indicating it may represent a more effective formulation. Furthermore, a detailed kinetic analysis would be processed in the future. [ABSTRACT FROM AUTHOR]

The experimental study presented in this paper aimed to investigate the effects of bolt number and their pattern on the failure time of minimally fire-protected glulam beam bolted connections. Four full-size glulam beam-end connection configurations reinforced perpendicular to wood grain with self-tapping screws (STS) were experimentally tested under exposure to elevated temperatures that followed the CAN/ULC S101 (Standard methods of fire endurance tests of building construction and materials. Underwriters Laboratories of Canada, Fifth edition, Ottawa, Canada, 2019) standard fire time–temperature curve. All metal connecting components (i.e., bolt heads and nuts and steel plate edges) were fire protected using wood plugs and strips, respectively. Throughout the duration of fire tests, all specimens were subjected to monotonic load causing bending moment equivalent to the maximum moment design capacity of the weakest unreinforced connection configuration. Fire test results show that the failure time of all four proposed wood–steel–wood connection configurations surpassed the 45-min mark, which is the minimum prescribed fire resistance rating for timber connections in applicable codes, with the two configurations that employed six bolts sustained the applied load for more than 60 min in standard fire conditions. Increasing the number of bolts from four to six enhanced the failure time of the proposed connection configurations with time increments more than those due to changing the bolt pattern. Most importantly, test results confirm that reinforcing the connections with STS fully curtailed wood splitting and averted row shear failure that is frequently encountered in similar but unreinforced connection configurations. [ABSTRACT FROM AUTHOR]

In the process of poplar fermentation for ethanol, different methods are adopted to achieve efficient treatment and resource utilization of fermentation residues, which meets the current demand for green energy and carbon neutrality. Therefore, this work aims to establish an evaluation method on energy consumption, pollutant emissions, and cost expenditures in the production process for biofuels from poplar wood and residue. The process was simulated with commercial software (Aspen Plus for chemical production simulation and cost estimation and eBalance for LCA). Results showed that compared to FCE, it made a higher conversion efficiency of CFG because of the biojet fuel and gasoline from the gasification and conversion of residual lignin. And the flash evaporator, hydrolysis reactor, and fermentation reactor were components with the highest exergy loss. The economic cost of CFG was 9.63% less than that of FCE, and cellulase enzymes and poplar wood in variable costs were main factors in the total cost. Comparing environmental impacts from four perspectives, it was found that the total comprehensive impact of FCE was higher than that of CFG under each weight. The degree of influence of the first level indicator layer was energy consumption, environmental impact, and economic cost in descending order. [ABSTRACT FROM AUTHOR]

This study investigated self-heating and off-gassing of Scots pine (Pinus sylvestris) wood pellets made from sawdust generated from separated mature and juvenile wood. The pellets were produced at an industrial scale and stored in large piles of about 7.2 tonnes. The production process involved drying the sawdust using three different methods and to varying moisture contents. The results indicated significant influences of both raw material type (F(6) = 61.97, p < 0.05) and drying method (F(2) = 65.38, p < 0.05) on the self-heating of the pellets. The results from the multiple regression analysis further showed that both the raw material type and pellet moisture content significantly influenced the temperature increase, with strong correlations observed for pellets produced using low-temperature drying (F(3, 14) = 83.52, multiple R2 = 0.95, p < 0.05), and medium temperature drying (F(3, 13) = 62.05, multiple R2 = 0.93, p < 0.05). The pellets produced from fresh mature wood sawdust were found to be more prone to self-heating and off-gassing while steam drying the sawdust at high temperature and pressure led to a significant reduction in heat and gas generation across all materials. The heightened self-heating and off-gassing in mature wood pellet can be attributed to a higher proportion of sapwood in the raw material. The probable explanations to the observed differences are in line with biological mechanisms for self-heating and off-gassing, as well as the chemical oxidation of fatty and resin acids. [ABSTRACT FROM AUTHOR]

Transparent wood has the potential to be a sustainable alternative to glass in the building and construction industry. However, it is crucial to consider the fire hazard in building applications. In this study, we applied a green strategy to treat the wood aerogel with an intumescent flame retardant coating. The coating consisted of positively charged polyethyleneimine (PEI) and melamine, as well as negatively charged phytic acid. The treated wood aerogel demonstrated excellent flame retardancy. Subsequently, we incorporated the flame-retardant wood aerogel into epoxy resin to examine its impact on the thermal stability and fire resistance of the epoxy. The wood aerogel, with two bilayers of PEI + melamine/phytic acid, significantly enhanced the fire resistance of the epoxy. This was evident through notable reductions in peak heat release rate (42%) and total heat release (15%). By characterizing the char residue of the epoxy/wood-2 composite, we observed the formation of a continuous network within the epoxy matrix, effectively impeding the transfer of combustible gases and heat. Our work presents a simple and environmentally friendly approach to producing multifunctional transparent wood. [ABSTRACT FROM AUTHOR]

Wood modification techniques, like densification, can improve the mechanical performance of low-density and undervalued wood species, rendering them suitable for high-value engineering applications. Nevertheless, densified wood (DW) commonly manifests a set recovery (SR) phenomenon when exposed to water, negating the enhancements achieved through densification. Our method addresses the SR issue and the non-recyclability associated with conventionally produced DW using chemical techniques in wood densification. To mitigate SR in DW, an ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate was impregnated as a cellulose plasticizing agent prior to wood densification. This method facilitated permanent deformation within the cellulose network, resulting in negligible SR. Moreover, the DW treated with IL (DW_1w) demonstrated an increase in both modulus of rupture and modulus of elasticity after water washing and subsequent redrying, in comparison to the untreated control (UC). Notably, spectroscopic (FTIR) analyses indicated that the chemical structure of DW_1w remained akin to that of UC. Additionally, the IL leached out during the DW-water washing step can be recovered. This research contributes to advancing sustainable alternatives to less ecologically friendly (chemical) pretreatment methods to reduce SR related issues in DW. [ABSTRACT FROM AUTHOR]

Polylepis (Queñua) is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism, which may be particularly threatened by climate change. Wood anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience, resistance, and recovery to extreme climates. Although the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively, our knowledge is relatively limited to quantitative differences in the main xylem tissues. To address this gap, we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability (semi-dry with high moisture and semiarid with dry winters). We selected hydraulic diameter, vessel density, vessel grouping index, solitary vessel index, vulnerability index, mesomorphy index, vessel element length, fiber length, fiber wall thickness, fiber lumen diameter, and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric stress. We performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic factors. Specific wood anatomical traits (vessel grouping index, vulnerability index, and fiber wall thickness) were dissimilar between xeric- and mesic-Polyelpis species. This study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel traits. Our findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna forests. By evaluating the effects of drought on wood anatomical characteristics and ecological function, we demonstrate the capacity of tree species to adapt and endure climate-related changes, thereby emphasizing their resilience and adaptability. [ABSTRACT FROM AUTHOR]

Carbon emissions and environmental concerns have led to the aspiration to reduce peat extraction and its use as a growing medium (GM). In Nordic Forest tree seedling production, Sphagnum peat has been almost exclusively used as a GM in seedling containers due to its good properties and availability. This study examined the feasibility of several peat-reduced and peat-free GM in container tree seedling production of the key tree species in Nordic forestry (Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L. Karst.) and silver birch (Betula pendula Roth) as well as Russian larch (Larix archangelica P. Lawson & C. Lawson ex Trautv.) and common alder (Alnus glutinosa (L.) Gaertn.). Pure or mixed GM, consisting of low-humified Sphagnum peat (pure as a control), harvested Sphagnum moss, wood fiber, cow manure digestate from a biogas plant, and a common reed compost were tested. Seedlings were grown in controlled conditions in greenhouse experiments and also in larger-scale commercial tree nurseries. Peat-reduced media containing peat of at least 50 vol% provided growth that is similar to pure Sphagnum peat for the tested species and container types. All the studied alternative media can yield marketable seedlings, although commonly of reduced size and requiring special adjustments in growing management. The studied media have a potential to reduce or replace peat in seedling production, but adjustments of their physical and chemical properties, as well as of seedling fertigation and management procedures, are required. The economic feasibility and environmental sustainability of these GM, as well as the outplanting success of seedlings grown in these media, remain to be studied. [ABSTRACT FROM AUTHOR]

Though awareness of fertilizer application has increased over time, low nutrient use efficiency is still a major limiting factor for eucalyptus plantations in India. A study was carried out to understand the nutrient dynamics under different soil fertility conditions by omission of macro nutrients (alone or in combination) and its comparison with balanced nutrient application (NPK) in short rotation Eucalyptus camaldulensis in southern India. This study revealed two phases of nutrient accumulation. The juvenile phase was characterised by an increase in nutrient uptake till canopy closure followed by a phase when the nutrient demand declined. The nutrient partitioning in different tree components changed with age. The rate of accumulation of N and K decreased in the order: leaves > bark > branches > wood > underground parts. The rate of accumulation of P, Ca and Mg decreased in the order: bark > leaves > branches > underground parts > wood. Balanced nutrient application gave 79% higher wood yield than control (no nutrient supply). This study conceptually and quantitatively compares the soil fertility regimes and explores the effect of nutrient limitation at the plant and plant-soil-level. Study also highlights the role of efficient nutrient management for sustainability of plantations, and ways to maximize yield, and improve soil nutrient balance at harvest. [ABSTRACT FROM AUTHOR]

Originating from furniture scraps, packaging, urban tree pruning, and construction waste, urban wood waste generates surprisingly large annual volumes. Due to its abundance and interesting physical–chemical characteristics for its use, it can be an excellent alternative for generating renewable energy for heat and electricity. In this context, urban wood waste's physical, chemical, and energetic properties were investigated, proposing alternative environmental routes for its introduction into the urban and industrial electricity sectors. Waste collected in Piracicaba (Brazil) was evaluated for physical and chemical composition, such as moisture, bulk density, particle size distribution, mineral contaminants, immediate chemical composition, chemical composition, and calorific value analysis. The waste studied presented potential characteristics for bioenergy generation, with ash and contaminant contents (such as metallic materials and sand) within the quality thresholds established by the energy sector. Among the waste materials analyzed, plywood, chipboard, wood, and OSB stood out for their high energy density (averaging 2.97 GJ/m3) and low ash content (averaging 1.13%). In contrast, MDF and hardboard exhibited lower calorific values and energy densities due to the wood cooking step in their manufacturing process, which could result in the loss of extractives and volatile materials. When categorizing the residues based on their characteristics, three distinct groups emerged, each associated with MDF, hardboard, or a combination of chipboard, OSB, wood, and plywood. This study's findings support the creation of public policies aimed at valorizing and reusing urban wood waste, contributing to solid waste management in cities of different countries while sustainably generating energy. [ABSTRACT FROM AUTHOR]

Currently, interfacial solar steam generation (ISSG) in desalinating water has become very popular for obtaining purified water from polluted water. However, finding an efficient evaporator with low cost is a challenging task for researchers. In this work, we introduce natural bamboo wood (BW) that acts as an interfacial evaporator for obtaining purified water. Four different wood evaporators namely, flat wood (BW-FW), two-cut grooved wood (BW-2G), four-cut grooved wood (BW-4G), and four-cut grooved with Co3O4-coated wood (BW-4G/Co3O4) are used to study the mass loss (ML), evaporation rate (ER), and evaporation efficiency (EY). From the observations, BW-4G/Co3O4 gives an admirable ML, ER, and EY of 4.4 g, 3.366 kg m−2 h−1, and 91.34% under 1 sun illumination for 60 min. Also, the BW-4G/Co3O4 evaporator is kept under natural sun illumination. It achieves 17.8 g of ML, 1.92 kg m−2 h−1 of ER, and 76% of EY respectively under 604.762 W/m2 solar illumination for 8 h. The reasons for the observed results are as follows: (i) the presence of grooves increases the exposing area for solar illuminations, (ii) super hydrophilicity nature of wood gives continuous replenishment of water from the bottom to the evaporative surface, (iii) the excellent salt rejection property of wood aids in continuous water transportation without salt accumulations. As a result of the condensed seawater samples, the ion concentrations (zinc, magnesium, cadmium, lead, copper, and sodium) come under WHO standards. Consequently, it gives better dye water separation from polluted water. [ABSTRACT FROM AUTHOR]

Using biodegradable material derived from renewable resources as petroleum-based plastics replacement is a promising way towards sustainable development. However, the insufficient mechanical properties and complex manufacturing process of bioplastics still need to be improved for high-quality food packages. Herein, we report a top-down strategy to transform natural wood into a clear wood packaging film through scalable delignification and polyvinyl alcohol (PVA) infiltration. The wood packaging film demonstrates a laminated structure with completely collapsed cell walls and PVA intertwined together after energy-saving air drying, resulting in high light transmittance with low haze, good mechanical performance, and high barrier performance for oxygen and water vapor. Molecular dynamics simulations reveal the underlying fracture mechanism between cellulose and PVA, which effectively enhances the Young's modulus and strength of the wood packaging film. These findings contribute to the development of biodegradable and strong packaging materials, as well as other food-related applications, using sustainable wood. [ABSTRACT FROM AUTHOR]

Forest management allows the sustained removal of significant amounts of carbon from the atmosphere. Within different activities in the forest, wood utilisation has the most significant man-made environmental impact which affects the carbon balance, which is important to know, to be able to accurately identify its role in climate change. This study aims to determine the carbon footprint of logging during utilisation based on scenario analysis in national default and theoretical assortment structures (11 additional scenarios for each forest stand) within the entire life cycle of raw wood products. Based on a common functional unit (100 m3 of cut wood), a comparative environmental life cycle analysis (LCA) for intermediate and final cutting was performed in shortwood forestry work systems in beech (Fagus spp.), oak (Quercus spp.), spruce (Picea spp.), black locust (Robinia pseudoacacia), and hybrid poplar (Populus x euramericana) stands in Hungary. After obtaining the results, the present study calculated the carbon footprint order for the utilisation life cycle phases and the entire tree utilisation life cycle. The distribution of absolute carbon footprint (ACF: considered emitted CO2 from fossil and biotic origins together) by final cutting exhibited the following order: hybrid poplar (6%)—spruce (8%)—beech (26%)—oak (27%)—black locust (33%). The ACF ranking for the whole technological life cycle (intermediate and final cutting, 400 m3 of cut wood) was hybrid poplar– spruce—oak—beech–black locust. The carbon footprint rankings of the studied stands were expanded to the national level. [ABSTRACT FROM AUTHOR]

Worldwide, silicified woods are found in many geological formations. Significantly, the organic materials of wood are no longer dominant; almost all wood fossils have been mineralized into inorganic silica materials. These unique geological processes must be understood to develop better understanding on organic material fossilization, particularly in the micron scale. Therefore, our aim was to characterize the composition of silicified wood using comprehensive microanalysis. The methods utilized were XRF, ICP-MS, XRD, FTIR, and FE-EPMA. Specimens are from Jasinga, West Java, Indonesia. The results showed that wood silicification was controlled by the infiltration of silica from the host rock into the spaces of the wood structure. In Jasinga, they are controlled by Pliocene tuffaceous sedimentary rocks. The ratio of silica phases revealed a trend in the degree of silicification. Besides silica, the distribution of trace elements also demonstrates the geochemical interaction between the wood fossil and host rock. Wood fossils are affected by the gradual replacement of organic carbon-based materials with silica through silicification. Silica enrichment occurs in the internal of wood, facilitates permineralization and recrystallization. Silica replaces organic material and preserves the wood structures. The microanalytical approach provides comprehensive perspectives on wood petrification, leads to better insights for paleontological studies. [ABSTRACT FROM AUTHOR]

Background: Wood carbon fractions (CFs)—the proportion of dry woody biomass comprised of elemental carbon (C)—are a key component of forest C estimation protocols and studies. Traditionally, a wood CF of 50% has been assumed in forest C estimation protocols, but recent studies have specifically quantified differences in wood CFs across several different forest biomes and taxonomic divisions, negating the need for generic wood CF assumptions. The Intergovernmental Panel on Climate Change (IPCC), in its 2006 "Guidelines for National Greenhouse Gas Inventories", published its own multitiered system of protocols for estimating forest C stocks, which included wood CFs that (1) were based on the best available literature (at the time) and (2) represented a significant improvement over the generic 50% wood CF assumption. However, a considerable number of new studies on wood CFs have been published since 2006, providing more accurate, robust, and spatially- and taxonomically- specific wood CFs for use in forest C estimation. Main text: We argue that the IPCC's recommended wood CFs and those in many other forest C estimation models and protocols (1) differ substantially from, and are less robust than, wood CFs derived from recently published data-rich studies; and (2) may lead to nontrivial errors in forest C estimates, particularly for countries that rely heavily on Tier 1 forest C methods and protocols (e.g., countries of the Global South with large expanses of tropical forests). Based on previous studies on this topic, we propose an alternative set of refined wood CFs for use in multiscale forest C estimation, and propose a novel decision-making framework for integrating species- and location-specific wood CFs into forest C estimation models. Conclusion: The refined wood CFs that we present in this commentary may be used by the IPCC to update its recommended wood CFs for use in forest C estimation. Additionally, we propose a novel decision-making framework for integrating data-driven wood CFs into a wider suite of multitiered forest C estimation protocols, models, and studies. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the performance and factors affecting the species classification of convolutional neural network (CNN) architecture using whole-part and earlywood-part cross-sectional datasets of six Korean Quercus species. The accuracy of species classification for each condition was analyzed using the datasets, data augmentation, and optimizers—stochastic gradient descent (SGD), adaptive moment estimation (Adam), and root mean square propagation (RMSProp)—based on a CNN architecture with three to four convolutional layers. The model trained with the augmented dataset yielded significantly superior results in terms of classification accuracy compared to the model trained with the non-augmented dataset. The augmented dataset was the only factor affecting classification accuracy in the final five epochs. In contrast, four factors in the entire epoch, such as the Adam and SGD optimizers and the earlywood-part and whole-part datasets, affected species classification. The arrangement of earlywood vessels, broad rays, and axial parenchyma was identified as a major influential factor in the CNN species classification using gradient-weighted class activation mapping (Grad-CAM) analysis. The augmented whole-part dataset with the Adam optimizer achieved the highest classification accuracy of 85.7% during the final five epochs of the test phase. [ABSTRACT FROM AUTHOR]

As major terrestrial carbon sinks, forests play an important role in mitigating climate change. The relationship between the seasonal uptake of carbon and its allocation to woody biomass remains poorly understood, leaving a significant gap in our capacity to predict carbon sequestration by forests. Here, we compare the intra-annual dynamics of carbon fluxes and wood formation across the Northern hemisphere, from carbon assimilation and the formation of non-structural carbon compounds to their incorporation in woody tissues. We show temporally coupled seasonal peaks of carbon assimilation (GPP) and wood cell differentiation, while the two processes are substantially decoupled during off-peak periods. Peaks of cambial activity occur substantially earlier compared to GPP, suggesting the buffer role of non-structural carbohydrates between the processes of carbon assimilation and allocation to wood. Our findings suggest that high-resolution seasonal data of ecosystem carbon fluxes, wood formation and the associated physiological processes may reduce uncertainties in carbon source-sink relationships at different spatial scales, from stand to ecosystem levels. Forest carbon source and sink processes may have contrasting climatic sensitivities. This analysis on 177 coniferous forest sites shows that carbon fluxes and wood formation are coupled but not fully synchronous at intra-annual scales, with peaks in cambial activity preceding those in photosynthesis and respiration. [ABSTRACT FROM AUTHOR]

Wood degradation by termites is a major concern for researchers, builders of timber-frame houses and stored wood products. This study aimed to determine the wood-degrading Isopterofauna in the cities of Yaoundé and Douala, Cameroon. Woods deposits and joineries workshops in the two cities were investigated monthly over 12 months, and termites were collected from wood species identified by their vernacular names. A total of 44 samples of wood-attacking termites were collected, grouped into two families (Rhinotermitidae, Termitidae), six subfamilies (Rhinotermitinae, Apicotermitinae, Coptotermitinae, Macrotermitinae, Nasutermitinae and Termitinae) and nine species. The species Nasutitermes arborum (14 samples) and Schedorhinotermes putorius (12 samples) were the most common in the city of Yaoundé. Only three species were found in Douala, mainly Coptotermes sp. (three samples). Of the 21 wood species examined in the two cities, Entandrophragma cylindricum hosted the highest termite species richness (six species). These findings are a milestone in the study of termites on lumber in storage and could be used by researchers and agents in the timber industry to make decisions regarding the application of pesticides on wood. [ABSTRACT FROM AUTHOR]

Water vapor sorption is a fundamental property of cellulosic materials. Numerous theoretical and empirical models have been developed to describe the relationship between water activity, temperature, and equilibrium moisture content (EMC). However, a meaningful connection between model parameters and thermodynamic properties related to the sorption process is often lacking. In cases where models yield thermodynamic properties, such as through use of the Clausius-Clapeyron equation, these are limited to temperatures where the ideal gas equation is applicable. In this paper we advance a thermodynamic framework and formulate a new semi-empirical sorption model based on the differential Gibbs energy of sorption as a function of EMC and temperature, intended for high temperature applications such as steam drying or fire modeling. We refer to this as the Comprehensive Analytical Sorption Thermodynamic (CAST) model. It has six parameters, includes temperature explicitly, and is invertible. The CAST model includes analytical equations for the differential enthalpy of sorption, the differential entropy of sorption, and the integral heat of wetting. The model is evaluated using sorption data and calorimetric data over a range of temperatures from the wood science literature and compared with several existing models. Overall, the CAST model fits the experimental sorption and calorimetric data with higher accuracy than existing models. [ABSTRACT FROM AUTHOR]

The actual study is the description of the biochemical characteristics of a wide range of enzymes (phenylalanine ammonia lyase, superoxide dismutase, catalase, peroxidase, polyphenol oxidase) and metabolites (malondialdehyde, phenols, extractives, cellulose, lignin), as well as the profiles of their activities during the xylem structural elements' formation during the predominance of differentiation processes during straight-grained wood formation or proliferation while the figured wood formation in the radial row cambial zone (Fraction 1)—differentiating xylem (Fraction 2)—mature xylem (MX) in the period of active cambial growth in 16-year-old straight-grained Betula pendula var. pendula and figured Betula pendula var. carelica plants. We generalized the processes associated with abnormal xylogenesis were separated spatially, and, to the greatest extent, the metabolism of the studied birch forms differed in the Fraction 2, while the diagnostic contribution of secondary metabolism enzymes and malondialdehyde (MDA) probably characterized the active secondary metabolism of parenchyma cells, which formed figured wood basis. This study described for the first time the biochemical features of a wide range of enzymes and metabolites as well as the profiles of their activities in the xylem structural elements' formation. The necessity of separately analyzing all tissue complexes was proven. This approach made possible to separate the generally observed biochemical patterns spatially. Thus, during the active cambial growth period in 16-year-old B. pendula var. pendula and B. pendula var. carelica, the differences between straight-grained plants and Karelian birch plants (non-figured and figured trunk parts) were most clearly expressed in the differentiating xylem. [ABSTRACT FROM AUTHOR]

Wood-based laminated composites with excellent strength and toughness have attracted much attention, but it is a challenge to process fast-growing natural poplar wood with poor mechanical properties into high-performance laminated composites without the use of adhesives. In this study, natural poplar wood was delignified and TEMPO-oxidized by a "top-down" strategy to obtain a wood scaffold with a cellulose content of up to 98%, which was then used as a substrate and impregnated with Ca2+ and PVA to form a large number of hydrogen and ionic bonds within the wood. Finally, under the action of hot pressing, laminated composites with high tensile strength (237 MPa), flexural strength (246 MPa) and impact toughness (50.45 KJ/m2) were obtained, which also displayed excellent thermal stability and water resistance. This work demonstrates that the utilization of renewable fast-growing poplar wood as a substrate and glue-free bonding method can produce low-cost, sustainable and high-performance wood-based laminated composites. [ABSTRACT FROM AUTHOR]

Sorption of water has a profound effect on the material properties of wood. The uptake of water vapour in wood and other materials releases more heat than the condensation of vapour to liquid water. This excess energy provides insights to the interactions and energy state of the absorbed water molecules. Modification of wood by acetylation is a common way of altering the wood-water interactions; however, very few data exist on how this and other types of modification affect the energy state of absorbed water in wood. This study is the first to use sorption calorimetry on modified wood to explore the effect of acetylation on wood-water interactions. Acetylation decreased the strength of the interactions between wood and water as seen from a decrease in differential enthalpy of mixing, both overall and in the dry state. It appears that acetylation removes or hinders the most-energetic interactions or bonding configurations of water in wood, perhaps because acetylation reduces the number of water-accessible hydroxyls more than it reduces the amount of absorbed water molecules. [ABSTRACT FROM AUTHOR]

Like many other anthropogenic habitats, log piles are mainly built in urban areas as a species-specific conservation measure for the European stag beetle (Lucanus cervus). As little is known about the success of this measure, we aim to study their success and longevity based on 100 small log piles that were followed up with emergence traps. Log piles were colonised the first year of building and beetles emerged up to 13 years later, with most beetles emerging after eight years. Overall, 67% of the log piles had emerging beetles: Quercus robur log piles (80%) were more successful than Fagus sylvatica (58%) and Populus x canadensis (50%). Overall, 177 ± 5, 131 ± 5 and 89 ± 5 beetles emerged per 1 m³ wood used in the log pile for oak, beech, and poplar respectively, but tree species had no effect on the size of the beetles. The emergence phenology was explained by a degree-day model with 6.6 °C as baseline temperature, predicting start and end of the emergence around 620 and 810 accumulated degree-days. Implications for insect conservation: We conclude that log piles are a successful conservation measure for the European stag beetle but distance to populations and abiotic characteristics need to be considered. For conserving this species in urban areas, we propose to build a network of log piles and to build new log piles about every ten years while retaining the old log piles. As the log piles are used by several species, they can also be useful for the conservation of other saproxylic species. [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]

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]

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]

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]

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]

Wood, a readily available and sustainable natural resource, has found widespread use in construction and furniture. However, its inherent flammability poses a potential fire risk. Although intumescent fire-retardant coatings effectively mitigate this risk, achieving high transparency in such coatings presents a significant challenge. In our approach, we employed a cross-linked network of phytic acid anion and N-[3-(trimethoxysilyl) propyl]-N,N,N-trimethylammonium cation to create a transparent "three-in-one" intumescent coating. The collaborative P/N/Si flame-retardant effect markedly improved the intumescent char-forming capability, preventing the wood from rapid decomposition. This resulted in a substantial reduction in heat release (13.9% decrease in THR) and an increased limiting oxygen index (LOI) value of 35.5%. Crucially, the high transparency of the coating ensured minimal impact on the wood's appearance, allowing the natural wood grains to remain clearly visible. This innovative approach provides a straightforward method for developing transparent intumescent flame-retardant coatings suitable for wooden substrates. The potential applications extend to preserving ancient buildings and heritage conservation efforts. [ABSTRACT FROM AUTHOR]

Despite a clear preference of the Eurasian Three-toed Woodpecker Picoides tridactylus for spruce trees as foraging sites by both males and females, some studies showed intersexual resource partitioning that allows competition for food to be minimized. The objective of the study was to characterize foraging sites of the Three-toed Woodpecker in the primeval stands of the Białowieża National Park (BNP, Poland) in relation to sex. Although the woodpeckers foraged on seven tree species, both males and females foraged predominantly on spruce (83% and 90% of the observations, respectively). Selection indices showed a significant preference for dead spruce trees for both sexes and additionally for live spruce trees in the case of females. Spruce trees where woodpeckers foraged were twice as thick as those available, regardless of whether they were dead or alive. The only feature differentiating the feeding sites of males and females was the diameter of the part of the tree at foraging locations. This suggests that there is some niche partitioning between the sexes of the Three-toed Woodpecker in primeval stands of the BNP. Our research clearly showed that even in the very rich environment of the BNP, abounding in various forms of dead wood, large dead spruce trees are crucial for the Eurasian Three-toed Woodpecker. [ABSTRACT FROM AUTHOR]

Functionalized monomer with specific chain length leads to different behaviors of UV-curable polymers. Due to the high demand for high-performance bio-based coating, this research was conducted to understand the effect of fluoroacrylate monomer (FAM) additions on physicochemical properties of palm oil-based polyurethane (POPU) coating. POPU oligomer was synthesized through a series of steps which was acrylation and isocyanation to form acrylated epoxidized palm oil (AEPO) and POPU oligomer, respectively. The POPU oligomer was further added with trimethylolpropane triacrylate and 1,6 hexamethyl diacrylate monomers at 60/30/10 wt% compositions respectively to form 100 wt% resin and followed by the addition of FAM at different concentrations (2–12 parts per hundred resin, phr). The sample was cast on a silicone mold at 1 mm thickness and cured under UV radiation for 60 s. The chemical structure elucidation was successfully done by NMR on AEPO and POPU. In 1H NMR analysis, C = C group was detected at 2.0–3.0 ppm and OH peak at 3.687 ppm. For POPU, peak at 3.0 ppm in 1H NMR analysis suggested that NH functional has formed. In 13C NMR, the existence of urethane linkage at 172 ppm further confirmed the reaction. The SEM and XRD results revealed that the addition of FAM induced separation between molecules, which lowered the crosslinking density of POPU coating. The thermal properties of POPU improved glass transition temperature (Tg) of the coating by 2.64% at the addition of 2 phr FAM. The physical properties of POPU was also improved as excellent adhesion properties of FPOPU was shown at 2–6 phr FAM addition: for glass (4B), wood (3B), and steel (5B to 4B). The hardness also improved across all substrates, such as glass (2H to 6H), wood (3H to 4H), and steel (7H to 8H). On the other hand, the addition of higher FAM concentrations (8–12 phr) showed a reduction in thermal properties as the Tg decreased by 7.54%. Moreover, physical properties of FPOPU also deteriorate as high concentration of FAM added. The hardness decreased for glass (6H to 3H) and steel (6H to 5H). Adhesion also decreased for all the substrates tested, including glass (3B to 2B), wood (3B to 2B), and steel (5B to 3B). The optimum FAM addition contributing to high adhesion, hardness and thermal performance was observed at 4 phr, and the best surface application was steel surface. [ABSTRACT FROM AUTHOR]

Biochars produced from different feedstocks and at different pyrolysis temperatures may have various chemical and physical properties, affecting their potential use as alternative microbial carrier materials. In this study, biochars were produced from pine wood and oak feedstocks at various temperatures (400°C, 500°C, 600°C, 700°C and 800°C), characterized, and assessed for their potential as carriers for Bradyrhizobium japonicum (CB1809) strain. The biochars were then stored at two different storage temperatures (28°C and 38°C) for up to 90 days. Furthermore, the study also explored the role of potentially ideal carriers as inoculants in the growth of Glycine max L. (soybean) under different moisture levels i.e., 55% water holding capacity (WHC) (D0), 30% WHC (D1) and, 15% WHC (D2) using a mixture of 50% garden soil and 50% sand. The results were compared to a control group (without inoculants) and a peat inoculant. Among all the materials derived from pine wood and oak, pine wood biochar pyrolyzed at 400℃ (P-BC400) exhibited the highest CFU count, with values of 10.34 and 9.74 Log 10 CFU g− 1 after 90 days of storage at 28℃ and 38℃, respectively. This was notably higher compared to other biochars and peat carriers. Significant (p < 0.05) increases in plant properties: shoot and root dry biomass (174% and 367%), shoot and root length (89% and 85%), number of leaves (71%), membrane stability index (27%), relative water content (26%), and total chlorophyll (140%) were observed in plants treated with P-BC400 carrier inoculant compared to the control at D2; however, lower enrichment of δ13C (37%) and δ15N (108%) with highest number of root nodules (8.3 ± 1.26) and nitrogenase activity (0.869 ± 0.04) were observed under D2, as evident through PCA analysis, showing more nitrogen (N) fixation and photosynthetic activity. Overall, this experiment concluded that biochar pyrolyzed at lower temperatures, especially P-BC400, was the most suitable candidate for rhizobial inoculum and promoted soybean growth. [ABSTRACT FROM AUTHOR]

Reducing the ignition temperature of aromatic volatile organic compounds (VOCs) is a long-term pursuit for environmental pollution treatment and industrial application. In this paper, the toluene catalytic combustion was ignited at ultra-low temperature of 73 °C over a poplar wood monolithic catalyst with highly dispersed Pd particles coated by nano-thick graphited carbon layer via in-situ carbonization. Combing the characterizations and DFT calculations, the satisfying catalytic performance could be attributed to two aspects: (i) the unrestricted mass transfer of reactant and the high dispersity of Pd were simultaneously ensured in the straight micrometer-channel with abundant surface anchoring groups of poplar wood; (ii) the nano-thick graphited carbon layer on Pd significantly enhanced the oxygen activation. Given the low cost of economic wood and facile preparation technique, this work opened up new alternative for the preparation of highly dispersed noble metal catalyst and the low temperature catalytic combustion of aromatic VOCs in industry. [ABSTRACT FROM AUTHOR]

To address drawbacks of significant toughness decrease of furfurylated wood and comprehensively improve properties of low-quality wood, this study synthesized hyperbranched poly(ester-amide) (HBP) as toughening agent and used synergies of furfuryl alcohol (FA) and HBP for poplar wood modification. The SEM–EDX and FTIR analysis showed that FA and HBP penetrated into wood and in situ polymerized in cell walls and cell lumina, leading to about 25% mass gain and 7% volumetric changes. After compound modification, wood exhibited enhanced hydrophobicity and dimensional stability, suggested by the maximum decrease of over 30% moisture content and volumetric change. This was mainly because polymers blocked water exchanging paths, reduced water accommodation, covered sorption sites and bulked cell walls. The flexural strength and surface hardness of modified wood were notably improved. The impact toughness increased by about 50% compared with that of furfurylated wood, which was mainly ascribed to (1) HBP with a three-dimensional globular structure had micro-phase separation with FA resin during polymerization. The HBP with high flexibility and mobility, acting as the second phase particles, increased the free volume for macromolecular movement. (2) The flexible group-ester group and tertiary amide group of HBP contributed to more absorption of energy and interruption of crack development under impact. Besides, the cracks would be blunted and dissipate impact energy by producing extensive shear deformation. (3) The HBP interrupted the cross-linking of furfural resin and reduced brittle furfural resin network dense. This study provided new references for improving toughness of resin-modified wood and upgrading low-quality wood products for wide application. [ABSTRACT FROM AUTHOR]

To achieve sustainable desalination and water purification, solar interface evaporation technology is an effective means due to its high energy efficiency. Reasonable photothermal conversion materials and surface design are crucial for the interfacial solar evaporation process. How to design water transport routes and thermal insulating layers simultaneously is one of the major challenges to solar interface evaporation technology today. Herein, this work reports an arch-shaped wood evaporator (pine@carbon black (CB)-metal-organic framework-801 (MOF-801)-36%) for efficient, fast and continuous interfacial solar evaporation, which is composed of an arch-shaped wood substrate, MOF-801, and CB as a light absorption layer. The arch-shaped structure has a double-sided evaporation effect, which has a synergistic effect on augmenting solar evaporation efficiency. In addition, the in-situ growth of MOF-801 in pretreated wood microchannels renders the wood evaporator a significant function of reducing the equivalent enthalpy of evaporation due to the reduction of the hydrogen bonding density of water molecules as they pass through the wood channels. The best evaporation rate of the arch-shaped wood evaporator can reach 2.535 kg·m−2·h−1, and the efficiency reaches 93.7% under the irradiation of 1 sun illumination. Notably, it could be used for desalination and wastewater treatment to collect fresh water that meets drinking requirements set by the World Health Organization (WHO). This integrated evaporator provides an efficient way for commercial portable photothermal conversion and new ideas for advanced solar-driven water treatment technology. [ABSTRACT FROM AUTHOR]

Plants adjust to abiotic conditions by changing their anatomical, morphological, and physiological traits. Traits can vary independently or in an integrated manner, known as trait variation and covariation respectively. It has been hypothesized that a trade-off would emerge along a gradient of abiotic constraints in which trait variation would be favored under resource-rich conditions while covariation under resource-limited ones. Although many studies have provided empirical support for this trade-off, a consensus has not yet emerged, due to a lack of support in some cases. This study investigated variation and covariation in three leaf and four wood traits of 74 woody species from a rainforest, a semideciduous forest, and a Restinga heath vegetation in the Atlantic Forest, which are subjected to different water-related constraints. We asked: Is there a variation-covariation trade-off within and across vegetation types? How does incorporating intraspecific variability change the magnitude and pattern of trait covariation? We found a variation-covariation trade-off and a positive relationship both within and across vegetation types. Wood variation was higher and covariation was lower in the rainforest, likely due to the greater water availability. Conversely, wood trait covariation was higher and variation was lower in the Restinga and seasonal semideciduous forest. Differences between vegetation types are likely related to the species' strategies to prevent hydraulic failure, particularly for Restinga species that adjust their wood density and xylem vessel density in a coordinated manner. Accounting for intraspecific trait variability increased covariation across all vegetation types, particularly in the Restinga. This highlights the loss of functional information when analyses are based solely on species' mean trait values. Our results also contribute to this discussion by providing evidence that the trade-off or a positive relationship between trait variation and covariation may be context-dependent. [ABSTRACT FROM AUTHOR]

Trees in breeding programmes are often selected at 1/4–1/3 of rotation, called 'early selection', which is typically between 8 and 10 years in radiata pine. However, differences between populations and genotypes selected for either basic density or wood stiffness are already apparent at age 2. We report the application of very early screening techniques for wood properties in the New Zealand Radiata Pine Breeding Programme deployment populations. Approximately 3000 trees representing three populations with 92 families and 10 clones were grown in a common garden trial, leaning for 21 months to separate compression and opposite wood. The trees were harvested and analysis carried out separately by wood type. The trial showed the existence of large variability in wood properties at early age, in some cases similar to variability near rotation age, and moderate to high degree of genetic control ( 0.35 ≤ h 2 ≤ 0.71 ). The genetic association between traits was strong, particularly between wood stiffness and longitudinal shrinkage ( - 0.69 ) and between longitudinal and volumetric shrinkage (0.83), suggesting that improving stiffness would also have a strong effect on improving dimensional stability. Basic density was also associated with stiffness and shrinkage, but with lower predictive capacity. These results can be used for roguing deployment populations-which already contain superior growing trees-and quickly upgrade the wood quality of seeds and clones currently available to New Zealand forest growers. We discuss necessary modifications to turn this research work into operation to screen any new material before commercial release. [ABSTRACT FROM AUTHOR]

The diversification of species for bioenergy silviculture in Amazonia will help several local and/or regional industrial segments. Thus, the expansion of knowledge on silvicultural practices of Tachigali vulgaris will support future commercial-scale plantations in Amazonia. This study aimed to evaluate possible differences in diameter, height, and wood volume of T. vulgaris trees grown under different nutritional doses, on two soil texture classes. In addition, we sought to determine the appropriate nutritional dose for the studied types of soil texture aiming at the production of energy wood. The study was conducted in two experimental areas of 1.6 ha each, located in the municipality of Almeirim – Pará, Brazil. Independent analyses were performed in both experimental areas at each age. The experiments were set up in a randomized block design with four blocks. A factorial scheme considering four phosphorus and three potassium doses were adopted, totaling 12 treatments. The diameter at 1.30 m (DBH), equivalent diameter, total height of the trees, and the commercial wood volume with bark per hectare (Vwb ha−1) were evaluated. A significant effect of nutrient doses was reported on DBH at the age of 2 years for the soil with a sandy loam texture. The Vwb ha−1 of the trees at 4, 5, and 6 years old was significantly affected by fertilization in clayey soils. Under the conditions of the present study, the nutritional doses of 0 kg ha−1 of triple superphosphate and 172 kg ha−1 of potassium chloride are recommended for the area with Oxisol of sandy loam texture and 195 kg ha−1 of triple superphosphate and 343 kg ha−1 of potassium chloride are recommended for the area with Oxisol of clayey texture. [ABSTRACT FROM AUTHOR]

Global climate crisis and severe water scarcity worldwide demand alternative genotypes that allow an adequate balance between production and water use while ensuring benefits for foresters. The genetic improvement of water use efficiency (WUE) in forest plantations could reduce water use without compromising yield. Above-ground biomass (AGB), saw-wood volume up to small-end diameter of 15 cm (V15), wood density (WD) and intrinsic WUE (WUEi) from wood carbon isotopic discrimination was evaluated in forty open-pollinated families of G. arborea grown in a tropical dry forest known as a water-limited environment, to select superior genotypes considering a balance in wood production and water use. Heritability of open-pollinated family means were moderate with values of h2f = 0.554 for AGB, h2f = 0.541 for V15, h2f = 0.608 for WD and h2f = 0.495 for WUEi. Significant genetic correlations between both WD and WUEi and production traits (p < 0.05) and a nonsignificant genetic correlation between WD and WUEi were found. Although production traits and WUEi showed moderate narrow-sense and family means heritabilities, considerable responses to selection of up to 13.7% in AGB, 15.5% in V15, 2.5% in WD and 3.0% in WUEi could be achieved from intensive selection of superior families. Our results showed that it may be possible balancing wood production and WUE by selecting open-pollinated families of G. arborea with higher V15 and WUEi. The deployment of these superior families can be used as a forest management strategy to adapt the species to future drought scenarios associated with global climate change. [ABSTRACT FROM AUTHOR]

The development of flame-retardant materials has become an important research direction. For the past dozen years, researchers have been exploring flame retardants with high flame-retardant efficiency, low toxicity, less smoke, or other excellent performance flame retardants. Therefore, this work aimed to synthesize new cyclodiphosph(V)azane derivatives and their Cu(II) and Cd(II) metal complexes and investigated their potential applications as high flame-retardant efficiency. Various techniques were used to characterize the prepared ligand H2L and its metal complexes, including elemental analyses, mass spectra, conductivity measurements, electronic spectral data UV–vis, FT-IR, 1H,13C-NMR, TGA, XRD, and molecular docking experiments studies were M. tuberculosis receptors (PDB ID: 5UHF) and the crystal structure of human topoisomerase II alpha (PDB ID: 4FM9). Wood-based paint was physically mixed with the ligand H2L and its metal complexes. The obtained results of mechanical characteristics of the dried paint layers were noticed to improve, such as gloss value, which ranged from 85 to 95, hardness 1.5–2.5 kg, adhesion 4B to 5B, and impact resistance, which improved from 1.3 to 2.5 J. Moreover, the obtained results of flame-retardant properties showed a significant retardant impact compared to the blank sample, such as ignitability, which includes the heat flux which increased from 10 to 25 kW/m2, and ignition time, ranging from 550 to 1200 s, respectively, and limiting oxygen index (LOI) (%) which has been increased from 21 to 130 compared with the plywood sample and sample blank. The ordering activity of the observed results was noticed that coated sample based on Cd(II) metal complexes > coated sample based on Cu(II) metal complexes of Cyclophosphazene ligand > coated sample based on phosphazene ligand H2L > coated sample without additives > uncoated sample. This efficiency may be attributed to (1) the H2L is an organophosphorus compound, which contains P, N, Cl, and aromatic six- and five-member ring, (2) Cu(II) and Cd(II) metal complexes characterized by high thermal stability, good stability, excellent performance flame retardants, and wide application. [ABSTRACT FROM AUTHOR]