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Wood Science and Technology
Journal Prestige (SJR): 0.659  Citation Impact (citeScore): 2 Number of Followers: 2  Hybrid journal (It can contain Open Access articles)ISSN (Print) 1432-5225 - ISSN (Online) 0043-7719 Published by Springer-Verlag  [2468 journals]
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- Facile one-step synthesis of cork-derived hierarchical porous carbons with
P, N, and O heteroatoms for high-performance supercapacitor electrodes-
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Abstract: High-performance electrodes of activated carbons (PNOACs) with P, N, and O heteroatoms were prepared through a simple one-step phosphoric acid activation method without the need for any dopants or post-treatment. In the preparation procedure, cork biomass material from Quercus variabilis was used as the precursor, and phosphoric acid was used as both the phosphoric resource and the activation agent. The pore structure, morphology, and physicochemical properties of the as-prepared carbons were investigated. In addition, the electrochemical performances of the PNOACs were evaluated using three-electrode and two-electrode systems (symmetric supercapacitor, AS). The results indicated that cork is promising as a low-cost and environmental-friendly precursor for producing high-performance supercapacitors electrode. Furthermore, galvanostatic charge–discharge analysis revealed a specific capacitance of 206 F g−1 at a current density of 0.5 A g−1, which can be attributed to the excellent hierarchical pore structure (micro-, meso-, and macropores) and suitable pore size distribution of the PNOACs. The specific surface area and total pore volume as high as 515.80 m2 g−1 and 0.29 cm3 g−1 were obtained, respectively. The presence of heteroatoms, namely N (0.81–1.07%), P (0.52–2.06%), and O (15.87–19.18%) content, on the carbon surface resulted in a considerable enhancement in the capacitive performance. Furthermore, a PNOAC sample, prepared at 600 °C with a mass ratio of 1:1, exhibited high long-term cycling stability (84.5%) and an energy density of 15.03 W h kg−1. Therefore, cork is highly promising as an electrode material for supercapacitors to attain exceptional electrochemical performance, as well as provide a new possibility for the utilization and valorization of high-value cork waste.
PubDate: 2023-05-13
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- A route of polyethylene glycol-based phase change heat storage wood with
AlN as the thermal conductive filler-
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Abstract: Wood is a great natural material with good energy storage and temperature adjustment for the energy crisis. In this study, wood was delignified, and the PEG-based eutectic polymer (PGMA) was impregnated into the delignified wood, and styrene (SM) grafted AlN was selected as thermal conductive filler to synthesize a stable phase change heat storage wood. The result shows that the styrene (SM) polymerized on the surface of AlN to form polystyrene (PS), and the dispersion of AlN was enhanced. The thermal stability and loss resistance of PCES-Wood are improved for the penetration of PS-AlN into the cavities, which is attributed to the PS-AlN playing a “limiting” role in the crystallization of PGMA. When the content of PS-AlN is 6%, the thermal conductivity of PCES-Wood reaches 0.5148 W/(m·K). 4% PS-AlN-PCES@Balsa has the lowest undercooling and heat loss rate, and the melting enthalpy and solidification enthalpy reach 125.60 J/g and 120.30 J/g, respectively. The phase change temperature range is between 19.59 and 33.87 °C, which is in the comfortable temperature range for humans. Under the illumination of the simulated solar light source, the surface temperature of PS-AlN-PCES@Balsa rises rapidly and shows a lasting heat storage capacity at low temperatures compared with the original wood. After 200 cold and hot cycle tests, the phase change enthalpy of PS-AlN-PCES@Balsa is still high, and there is a slight leakage phenomenon. The phase change wood prepared in this study shows that it is a potential material to store and release solar energy in practical applications.
PubDate: 2023-05-06
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- Prediction of moisture-induced cracks in wooden cross sections using
finite element simulations-
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Abstract: Wood absorbs and desorbs moisture due to its hygroscopic behavior, leading to moisture gradients in timber elements as well as swelling and shrinkage. These processes are constrained due to the orthotropic material properties of wood, leading to moisture-induced stresses, which can cause crack initiation and propagation. A significant amount of the damage in timber constructions indoors can be related to changes of the moisture content (MC). However, more information is needed about the correlation between moisture changes or gradients and specific damage characteristics, like crack depths. Thus, based on numerical simulations, the crack depth development within two solid timber and one glued laminated timber (GLT) cross section over time for different relative humidity (RH) reductions and initial MCs is analyzed. For this purpose, a multi-Fickian transport model is used to determine moisture fields, which are then used as loads in a subsequent stress simulation, where linear elastic material behavior is considered. An extended finite element approach, supported by a multisurface failure criterion defining the failure behavior, allows for the simulation of moisture-induced discrete cracking. Based on simulation results, correlations between potential maximum crack depths and moisture gradients in indoor climate conditions are derived, which enables the prediction of crack depths in wood. Finally, it is shown that the initial MC level significantly influences the maximum crack depth that can be expected.
PubDate: 2023-04-27
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- Toward a logistic model of dynamic mold growth on wood
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Abstract: This paper deals with mathematical modeling of mold growth on wood. The logistic growth equation is used to model mold growth phenomena in changing environmental conditions. Microscopic mold coverage fraction is used in the logistic equation to represent mold development on a material surface over time. The current state-of-the-art dynamic Finnish mold growth model is used as the reference model for development of the logistic mold growth model. The optimal values of mold growth coefficient are estimated by simulations of mold growth under constant environmental conditions and by finding the best agreement with the Finnish mold growth model using mathematical optimization methods. It is shown that the mold growth coefficient can be approximated as a function of relative humidity, temperature, wood species and the quality of the surface. The model parameters are then verified by a comparison with the Finnish mold growth model. In this case, cyclic step changes of constant relative humidity are used. Finally, the logistic mold growth model is compared with published experimental observations of mold growth. The discrepancy of mold growth models and experimental mold growth data, and possible improvements are discussed.
PubDate: 2023-04-26
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- Maturation-related phenolic compounds in cachaça aged in oak barrels:
influence of reuses-
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Abstract: The aging process, although not mandatory in the production of cachaça, adds sensory complexity to the beverage. During the aging process, several physicochemical reactions occur between the wood and the distillate, such as hydrolysis, oxidation, polymerization, and esterification. The phenolic compounds related to maturation, extracted from the wood, directly interfere in the chemical and sensory composition of the distillate. However, knowledge of wood composition is not enough to determine the sensory profile of cachaça, since this also depends on numerous factors such as the origin of the wood, wood species, barrel manufacturing, number of times the barrel was used, aging time, and composition of the beverage. This research explores, quantitatively and qualitatively, the influence of these factors on the extraction of phenolic compounds derived from lignin in cachaça aged up to 144 months in oak barrels of different origins using high-performance liquid chromatography. The content of phenolic compounds increased at an accelerated rate in the first years of aging. Nonetheless, the wood species and the number of times the barrels were used exhibited great influence on the evolution of aging, regardless of the aging time. Regarding the extraction of maturation indicators, each year of aging in new barrels corresponded to approximately 5 years of aging in extensively used barrels.
PubDate: 2023-04-26
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- Fractal dimension of wood cell wall pores from pore size distribution:
insights from nitrogen gas adsorption analyzer-
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Abstract: Understanding wood cell wall pore geometry and distribution is the basis for studying its macroscopic properties. This research investigated the pore fractal dimension using the pore size distribution of selected softwoods and hardwoods. Nitrogen gas analyzer was used to study the detailed structural parameters of wood pore size distributions and use as a raw data to assess their fractal dimension. The results revealed significant variability in pore size distribution, porosity, pore volume, specific surface area, and fractal dimension. The cell wall pore size distribution ranged from 1.41 (minimum) to 442 nm (maximum). Western red cedar heartwood and sapwood show a higher and lower number of micropores, respectively, in the wood cell wall. The results also showed that the fractal dimensions of the cell wall pore spaces of wood vary between 2.92 and 2.97. There was no significant difference in fractal dimensions between wood types and species.
PubDate: 2023-04-21
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- Effect of solvent type and pH degree on the chemical composition of kraft
black liquor via ARAS method-
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Abstract: It is barely known that the wastewater, or black liquor, released during the transformation of wood into paper is rich in carbon due to its lignin content. While the chemicals used in paper pulping are recovered by separating them from the black liquor, the value-added chemicals are wasted as they are burned. This study aims to determine how these value-added chemicals dissolved in black liquor and wasted through burning, can be utilized simply and efficiently. To examine the changes in black liquor chemical content, kraft black liquor samples obtained from Pinus brutia (PB) and Populus tremula (PT) woods were adjusted with 1 MH3PO4 to pH 5.5, 7 and 8.5. Chloroform (C), toluene (T) and dichloromethane (DM) were used as solvents for liquid–liquid extraction of the value-added chemicals. High-pressure liquid chromatography (HPLC) was used for both qualitative and quantitative analyses. The Additive Ratio Assessment (ARAS) method determined that the optimal conditions for recovering value-added chemicals were obtained with PT at pH 5.5 with DM as a solvent.
PubDate: 2023-04-20
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- Effect of heat treatment on the electrical conductivity of
carbon–nitrogen onion nanomaterial based on the interpolyelectrolyte
complex lignosulfonate–chitosan-
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Abstract: The effects of the second step pyrolysis temperature on surface, structure, texture properties, and electrical conductivity of carbon onion nanomaterials based on the interpolyelectrolyte complex lignosulfonate–chitosan were studied. The results indicate that higher temperature of heat treatment leads to improvement of the porous structure and allows to obtain a carbon material with high value of specific electrical conductivity. The second step of heat treatment makes it possible to more fully remove oxygen- and hydrogen-containing functional groups from the carbon–nitrogen nanomaterial and increase the number of carbon–carbon double bonds, while a significant amount of built-in nitrogen is retained in the onion structure, which contributes to a significant decrease in electrical resistance. After the second step of the heat treatment, the specific electrical conductivity of the samples increased by 5–10 orders in comparison with initial carbon sample obtained at 600 °C. Experimental values for electrical conductivity of carbon onion nanomaterials were (1.67–2.98)·10–2 S cm−1, (0.27–0.38)·10–2 S cm−1 and 1.2–2.2 S cm−1 for materials obtained at 900, 1100 and 1300 °C, respectively. Carbon nanomaterials are promising for practical use as electrically conductive dispersed particles in semiconductor technology.
PubDate: 2023-04-20
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- A novel three-dimensional model for the prediction of ultrasonic velocity
in wood considering its orthotropy-
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Abstract: This paper deals with a three-dimensional model capable of determining the propagation velocities of ultrasound waves in wood. Considering simultaneously the three planes of orthotropy and using a spherical coordinate system, the mathematical expression of this model is proposed. The model is based on the two-dimensional Hankinson models commonly used for the characterization of velocities in each orthotropic plane. The model is composed of six (6) parameters. Three velocities in the main directions (VL, VR and VT) and three calibration coefficients (l, m and n) correspond to the three orthotropy planes. The experimental validation is based on ultrasonic measurements taken on a Douglas fir cube. A finite element support is used to recalculate the propagation velocities whatever the orientation of the propagation line by considering a cylindrical orthotropy induced by the construction of growth rings. The process of determining the model parameters (VL, VR, VT, l, m and n) by an inverse analysis algorithm is presented. The results show that the model improves the fit to the observed angular dependencies of the wave propagation velocities. The model predicts well the velocities outside the principal planes.
PubDate: 2023-04-20
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- Hygroscopy and adaptive architectural façades: an overview
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Abstract: Hygroscopic properties of wood have been utilized in adaptive façades to respond to variation in humidity levels. Shape-shifting materials have been developed to replace mechanical actuators that respond to climatic variation with zero-energy consumption. This paper presents a systematic review of the literature on the use of hygromorphic behaviour in developing adaptive architectural façades, with the primary focus of identifying the venues of implementation of hygroscopic actuation in adaptive facades. The paper triangulates the intersection between hygroscopic design parameters with manufacturing strategies and their application as a passive motion mechanism in adaptive facades. This review focuses on state-of-the-art experimental work in hygroscopic design, with specific interest in manufacturing methods of hygromorphic adaptive façades, response motion behaviour evaluation and tracking, analysis of the current applications of hygromorphic design in real weather conditions, and performance prediction. Results reveal that most of the studied papers focus on the response behaviour of programmable materials to variation in moisture content and the implementation of hygroscopic design in adaptive façades. From the literature analysis, it was shown that programming the response behaviour of hygroscopic materials mainly takes place through variation in fabrication methods, followed by passive layer configurations, which act as actuators that are controlled by differences in layer properties.
PubDate: 2023-04-08
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- Modification with carboxymethylation-activated alkali
lignin/glutaraldehyde hybrid modifier to improve physical and mechanical
properties of fast-growing wood-
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Abstract: A novel, environmentally friendly, biomass-based modification technique utilizing carboxymethylation-activated alkali lignin (CAAL) and glutaraldehyde (GA) is proposed to enhance the physical and mechanical properties of poplar and fir wood. Water-soluble CAAL was prepared by modifying alkali lignin (AL) with sodium chloroacetate following low-temperature activation under a NaOH/urea system. AL is a biomass-based material from industrial by-products. As such, it does not rely on fossil resources nor emit volatile compounds that might limit its range of application. The successful preparation of CAAL was demonstrated by Fourier transform infrared spectroscopy (FTIR), 1H nuclear magnetic resonance spectroscopy (NMR), and 13C NMR, and the changes in structure were analyzed by 2D-heteronuclear singular quantum correlation (2D-HSQC), 31P NMR, and gel permeation chromatography (GPC). The following characteristics of the modified wood samples were investigated in detail: weight percent gain (WPG), bulking, anti-swelling efficiency (ASE), water absorption rate (WAR), leachability of the modifier, microstructure, and mechanical properties. Water immersion results demonstrated that the CAAL/GA hybrid modifier enhanced ASE to 41.3% and 31.5% for fir and poplar, respectively, at a concentration of 15 wt.%. Furthermore, the WAR of fir was reduced by nearly three times to 30.7%, compared to that of a control sample treated solely with GA. GA-treated samples showed high brittleness, whereas both poplar and fir showed enhanced modulus of rupture and elasticity following treatment with the CAAL/GA hybrid modifier.
PubDate: 2023-03-28
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- Physicomechanical properties of raw and comminuted pine and poplar
shavings: energy consumption, particle size distribution and flow
properties-
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Abstract: The aim of this study was to assess the energy consumption during milling and cutting-milling of pine and poplar shavings and the determination of particle size distribution (PSD) characteristics and mechanical properties of these materials. Cutting-milling process required less energy (in kJ·kg–1) than milling but maximum mass flow rate of shavings was significantly higher and thus the effective power requirement of the knife mill during cutting also was higher. Comminution of plastic poplar shavings was more energy-consuming than harder pine shavings. These features influenced PSD, which was approximated with four mathematical models: Rosin–Rammler-Sperling-Bennett (RRSB), normal, logistic and lognormal. On the basis of the best fitting (Radj2) for RRSB, detailed PSD parameters were calculated and all PSDs were described as ‘mesokurtic’, ‘fine skewed’ and ‘well-graded’. In comparison to milled shavings, cut-milled shavings had higher density, but were less compressible and had lower unconfined yield strength. However, cut-milled shavings had higher flowability because of lower cohesion and internal friction angles, because after cutting-milling particles were more spherical than elongated particles after milling. Cut-milled poplar shavings had more favourable mechanical parameters and better PSD characteristics, but required more energy for comminution than pine shavings.
PubDate: 2023-03-25
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- Enhancing the selective separation of hemicelluloses from cellulosic
fibers in NaOH/ZnO aqueous solution-
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Abstract: To achieve a breakthrough in the application of cold caustic extraction, it is necessary to limit the amount of alkali and to dissolve the hemicelluloses sufficiently. A NaOH/ZnO aqueous solution system was used to separate hemicelluloses from bleached bamboo pulp efficiently and selectively. The NaOH/ZnO process proved to be more successful in the removal of hemicelluloses. Under the conditions of 0.5% ZnO concentration, the NaOH/ZnO aqueous solution system decreased the hemicelluloses content to 4.99%, which was lower than 7.46% of the control sample treated with NaOH alone at the same 7% NaOH concentration. Correspondingly, the NaOH/ZnO system led to an increase in alpha-cellulose content with significantly improved hemicelluloses removal efficiency and selectivity. As a result of the NaOH/ZnO process, a higher degree of polymerization was observed, and the cellulose I structure was always maintained, which provided good benefits for the subsequent utilization of cellulose.
PubDate: 2023-03-06
DOI: 10.1007/s00226-022-01437-3
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- Preservation status and microbial community of waterlogged archaeological
woods over 7800 years old at the Jingtoushan Site, China-
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Abstract: The Jingtoushan Site (8300–7800 BP), located in Ningbo City, Zhejiang Province, is of great value for the in-depth understanding of China’s prehistoric coastal culture. At this site, numerous valuable wooden relics showing past human civilization have been discovered. Multiple approaches were taken, including wood anatomy and physicochemical analyses, to assess the preservation state of waterlogged archaeological woods (WAWs), while using high-throughput sequencing (HTS) to explore their microbial diversity and composition as well as that of the surrounding soil. The secondary walls of WAWs showed to be severely degraded, whereas the compound middle layer and cell corner were well preserved. Bacteria were the main microorganisms causing the biodegradation of WAWs, and 85.6% of the phyla was also found in the surrounding soil environment. Specifically, Arcobacter, Flavobacterium, Hyphomicrobium, Pseudomonas and Sphingomonas, bacteria retrieved by HTS in high abundance, were inferred to be potentially associated with the biodegradation of WAWs at the Jingtoushan Site. Meanwhile, it is hypothesized that lignin in the wooden artefacts still buried and unexcavated at the Site might be at risk of further degradation, although it may be better preserved than the cellulose and hemicellulose.
PubDate: 2023-03-02
DOI: 10.1007/s00226-023-01463-9
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- Determining the pore structure and radial variability of moso bamboo
(Phyllostachys edulis)-
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Abstract: The native pore structure and characteristic are the basis for studying the permeability, pretreatment and further processing of bamboo. Herein, the porosity, surface area, pore volume and pore size distribution of moso bamboo and their radial variabilities were investigated by a combination of mercury intrusion porosimetry (MIP), nitrogen adsorption and scanning electron microscopic image analysis. Bamboo has a wide porosity range (48 ~ 70%) that exhibits a quadratic polynomial relation to the radial position, and parenchyma tissue shows higher surface porosity (around 71%) compared to vascular bundles (50.5 ~ 20.3%). The cell wall pores uncovered by MIP and N2 adsorption display the meso- to macropores abundant characteristics and the mesopores account for 54.5 ~ 62.4%. Different radial samples demonstrate the similar pore size distributions but variable volumes and surface areas (85.3 ~ 88.2 m2/g). The outer part of bamboo has these values smaller than that of middle and inner samples, revealing a more compact structure. The present work gives an in-depth view on bamboo pore structure and radial heterogeneity, which could provide the basis for pretreatment and subsequent development of value-added bamboo products.
PubDate: 2023-03-01
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- Luminescent transparent wood from balsa wood loaded by graphite carbon
nitride for application in photoelectric device-
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Abstract: In this study, metal-free wood-based encapsulating materials for white light-emitting diode were obtained by using renewable transparent wood as the biological support and the light scattering component, and graphite carbon nitride as the color light emitting component. The graphite phase carbon nitrides with blue and green color were prepared by thermal polymerization through structural regulation of raw materials. The resulting different color phosphors were mixed with epoxy resin, respectively, and then, blue epoxy resin, green epoxy resin and red epoxy resin were mixed with a mass ratio of 4:2:1 and a proper amount of curing agent. The delignified balsa wood with high porosity was vacuum impregnated with epoxy resin mixture to obtain white luminescent transparent wood with better performance such as high transmittance and high haze. This work provides a feasible solution for the sustainable development of transparent wood and the application of transparent wood to photoelectric materials.
PubDate: 2023-02-20
DOI: 10.1007/s00226-023-01459-5
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- Biomorphic porous TiO2 with wood template size scaling for improved
adsorption and photocatalysis performance-
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Abstract: Biomorphic TiO2 with hierarchical porous structures for photocatalytic degradation is fabricated by templating wood residues of different size scales (lignocellulose, wood flour, and solid wood as biological templates) using a simple sol–gel method. Compared to template-free TiO2, the biomorphic TiO2 had a better adsorption capacity and photocatalytic performance when decomposing methylene blue (MB) and phenol. The lignocellulose-templated TiO2 reached adsorption equilibrium within 60 min because of a composite hierarchical structure with the complex interlaced wood, and demonstrated 98.9 and 84.3% degradation of MB and phenol within 60 min under visible light conditions. The multiscale structures of these wood templates enhanced light absorption and mass transfer efficiency due to the presence of additional surface hydroxyl groups and a reduced bandgap. This research proposes a convenient synthesis method to obtain biomorphic TiO2 using wood residues and modifies the physio-chemical interaction between wood and TiO2 to enhance the visible light response and transfer of photogenerated charge carriers in the system.
PubDate: 2023-02-14
DOI: 10.1007/s00226-023-01462-w
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- Exploring the effect of lignin on the chemical structure and
microstructure of Chinese fir wood by segmental delignification-
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Abstract: This study proposed a new method for the rapid and uniform removal of lignin components from wood, which was applied to abundant fast-growing Chinese fir. Based on the lignin removal using acidic NaClO2, the impregnation process with positive pressure-negative pressure circulation was used to promote the reaction. Using this method, the time of the impregnation and discharge of lignin was shortened, and the complete cellulose skeleton of Chinese fir can be easily prepared. The lignin removal effect on crystalline structure and chemical structure was discussed. It was deduced that the macroscopic morphology of Chinese fir was complete and the end face did not crack under the positive–negative pressure cycles. The FTIR showed that the proposed method can better reduce the damage of holocellulose by delignification treatment and uniform and efficient removal of lignin. The relative crystallinity gradually increased with the increase in the cycle number, achieving a selective delignification effect. This method achieved accurate regulation of the lignin removal effect, promoted the utilization of Chinese fir in functional materials, and provided a cellulose wood-based template for the high-value utilization of Chinese fir.
PubDate: 2023-02-10
DOI: 10.1007/s00226-023-01461-x
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- Well-controlled SI-ARGET ATRP of EGDMA for maintaining the dimensions of
waterlogged archaeological wood-
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Abstract: Controls over the dimensions of waterlogged archaeological wood (WAW) upon drying are a critical issue for its conservation. Surface-initiated activator regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP) has been proven to be an effective consolidation method to increase the dimensional stability. However, the drawback of the current method is that the expansion stress generated during graft polymerization cannot be well controlled. An improved SI-ARGET ATRP system using a bifunctional monomer ethylene glycol dimethacrylate (EGDMA) to introduce a cross-linking process during the polymerization is presented in this paper. Both Pinus massoniana and Sapium sp. samples with different maximum moisture contents as 507% and 863%, respectively, show a reduced volumetric shrinkage of around 5% without any expansion phenomenon after the treatment. This method shows potential applications in the field of WAW conservation and may provide a new solution for consolidation of other organic archaeological objects as well as developing new wood-based materials.
PubDate: 2023-01-29
DOI: 10.1007/s00226-023-01454-w
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- Water vapor sorption characteristics and hysteresis of earlywood and
latewood within the same growth ring of Catalpa bungei-
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Abstract: Catalpa bungei is an economically important native hardwood in China whose hygroscopic behavior is vital for industrial applications as it influences the final product’s dimensional stability and mechanical properties. In this study, the adsorption and desorption behavior of earlywood and latewood in the same growth ring of C. bungei wood samples was documented using a dynamic vapor sorption resolution and analyzed using the Guggenheim–Andersen–de Boer (GAB) model. The earlywood and latewood exhibited varying sorption isotherms and hysteresis degrees, and the reasons were analyzed in terms of structure and chemical composition (mainly hemicellulose and lignin). The influence of benzene–alcohol extracts and vessels on sorption characteristics was also examined. The GAB model perfectly fits the experimental data (R2 ≥ 99.7%) over the full relative humidity range. Specifically, parameters such as the internal specific surface area of wood can be obtained from the GAB model to help explain the differences in sorption properties between earlywood and latewood. The maximum water content bound to the primary sites for earlywood and latewood is 6.87% and 7.47%, respectively. Correspondingly, two internal specific surface areas are 261 m2/g and 284 m2/g, respectively. The adsorption isotherms of earlywood and latewood in C. bungei cannot be fully classified as type II.
PubDate: 2023-01-29
DOI: 10.1007/s00226-023-01457-7
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