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European Journal of Wood and Wood Products
Journal Prestige (SJR): 0.624  Citation Impact (citeScore): 1 Number of Followers: 3  Hybrid journal (It can contain Open Access articles)ISSN (Print) 0018-3768 - ISSN (Online) 1436-736X Published by Springer-Verlag  [2468 journals]
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- Colour sorting of red oak, yellow poplar and maple veneers using
self-organizing map: comparisons between different camera genres-
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Abstract: Colour sorting is a vital process in manufacturing of high-quality wood products. It is however a manual process in a large majority of manufacturing facilities in Malaysia. Automation is an ideal solution; however, costs are prohibitive for small and medium industries (SMI). This project aims to produce a flexible solution that can cater for manufacturers of different scales. Three cameras of different price ranges were used: (i) Hikrobot® MV-CE200-10UC (CE200), (ii) Logitech® C920 HD Pro (C920), and (iii) Sony® RX0 II (RX0 II). After setting up a veneer imaging prototype, human sorted images of American red oak (Quercus rubra), yellow poplar (Liriodendron tulipifera), and maple (Acer spp.) were acquired. After performing image preparations and calibrations, 26 features were extracted from each image. The features were based on the average and standard deviation of the wood basal colour and wood grain colour. Salient features were obtained using Sequential Forward Selection (SFS), which were then used to train a Self-Organizing Map (SOM). The results affirmed that the colour of the basal colour is highly correlated with human sorted colour groups. As expected, CE200 performed the best being of industrial grade. Interestingly, C920 exhibited comparable performance to CE200. RX0 II performed the worst due to its interface software limitations. This proposed system achieved accuracies of 89.0% for red oak, 94.3% for poplar and 96.4% for maple. This research will assist the SMI to develop affordable vision systems for colour sorting.
PubDate: 2023-06-01
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- Production and characterisation of self-blowing lignin-based foams
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Abstract: Self-blowing lignin-furanic foams were produced using formulations comprising Kraft lignin and furfuryl alcohol as the major components. Diethyl ether, Tween 85 and sulphuric acid were used as blowing agent, surfactant and catalyst. The influence of the components and the ratio of furfuryl alcohol to lignin was investigated with regard to the foam density, mechanical properties, water absorption, thermal properties, and fire behaviour. Depending on the formulation, the density of lignin-furanic foams ranged between 60 and 320 kg m−3. Increasing the furfuryl alcohol content increased the density of the foams. Low-density foams were obtained with a higher proportion of diethyl ether. The compression strength and modulus of elasticity (MoE) of lignin-furanic foams also increased with foam density. All lignin-furanic foams showed good thermal stability and residual masses by thermogravimetric analysis. Cone calorimetric analysis showed that lignin-furanic foams have poor flammability and self-extinguish within few seconds.
PubDate: 2023-06-01
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- Fiber properties and chemical compositions of sheaths from three selected
sympodial bamboo species as raw materials for papermaking in Yunnan of
China-
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Abstract: The fiber properties and chemical compositions of Fargesia yunnanensis, Neosinocalamus affinis and Dendrocalamus farinosus sheaths at different growth stages were investigated. Sheaths contained short and medium-sized fibers. Both the slenderness ratio and Runkel ratio showed good suitability of the sheaths as raw material for papermaking. Shedding sheath of N. affinis were found to be the best as they exhibited a better slenderness ratio and Runkel ratio, as well as low ash, moderate SiO2 and greater holocellulose content, whereas F. yunnanensis sheaths provided the poorest results.
PubDate: 2023-06-01
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- Effects of acetylation on moisture sorption of wood under cyclically
changing conditions of relative humidity-
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Abstract: Dynamic moisture changes affect practical wood processing and wood utilization. To evaluate the effect of acetylation on dynamic moisture sorption of wood, acetylation was controlled at two levels by adjusting the reaction time. A cyclically changing condition was created where the relative humidity changed from 45 to 75% sinusoidally at 25 °C. Moisture content of wood was automatically recorded in time. The two-level acetylated wood exhibited 12.3% and 17.8% mass gain and 7.7% and 9.4% volume increase respectively. Moisture content against time for acetylated wood changed in a similar sinusoidal curve to relative humidity. Higher acetylation resulted in a greater decrease in dynamic moisture sorption as indicated by over 54% decrease in moisture content, about 26% decrease in amplitude and about 23% decrease in moisture sorption coefficient. This was mainly because higher acetylation caused larger cell wall bulking of wood. More hydroxyl group substitution also reduced the dynamic interaction of water molecules and wood in a certain time. The phase lag was reduced by acetylation mainly due to the decrease in the amplitude. Higher acetylation led to lower sorption hysteresis, since the swelling of wood after higher acetylation was lower and less relaxation time was needed for the matrix during moisture sorption. Moreover, acetylation decreased hydrophobicity of wood and facilitated more evaporation of water molecules during desorption. Consequently, the sorption hysteresis decreased. The results can help understand the dynamic interactions between acetylated wood and water and better control wood acetylation according to practical processing requirements.
PubDate: 2023-06-01
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- Production of wood-based panel from recycled wood resource: a literature
review-
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Abstract: This article presents and discusses the available studies on utilization of waste wood (WW) resource for wood-based panel production. The cited literature indicated that the majority of WW research was from Europe and conducted mainly on recycled material from particleboard. In addition, particleboard was presented as the first option of wood-based panel product manufactured from waste wood. There was a lack of research on the recycling of plywood. Physical and chemical contaminants fluctuated strongly between low- and high-quality recycled wood mixes depending on their origins. Findings from studies also noticed that wood-based panels (e.g., particleboard) could be produced from 100% WW. However, the physical and mechanical properties of wood-based panel drop with the high proportion of WW content due to the decrease in slenderness ratio and increase in contaminants. Moreover, formaldehyde emission content of particleboard and Oriented Strand Board (OSB) manufactured from WW particles increases when the WW percentage increases. Contrary, the formaldehyde amount decreases with the increase in recycled fiber content in fiberboards. Notably, the properties and emission of recycled wood composite products could be improved by applying high-tech sorting technologies, appropriate chipping techniques, pretreatment steps and formaldehyde-free binders during waste wood handling and production process.
PubDate: 2023-06-01
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- Investigation of the ınnovation of traditional wood marquetry technique
with CNC laser technology: a design study-
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Abstract: The efforts of people seeking better design have enabled decoration techniques in the wood industry to develop over time and gain a technical dimension. In addition to basic features such as function and durability of furniture, people have also given importance to wood ornamentation from the past to the present. One of the most important of these is the marquetry technique. Traditional marquetry decoration technique can be done over a long period of time with motif design, tool selection and qualified workmanship. This study aims to examine the producibility of marquetry with laser technology, to determine its advantages and disadvantages compared to the traditional method and to contribute to making this method suitable for industrial mass production. For this purpose, a computer numerically controlled (CNC) carbon dioxide gas laser machine was used in the study. In the workshop environment, traditional and laser production of wooden marquetry was made. In the application study, a case study was done by producing a coffee table set. The data obtained from the findings and observations in the production process were evaluated. As a result, it has been determined that the production of marquetry with CNC laser has some limitations compared to the traditional method, but its advantages are quite high. In the industrial wood product sector, it was found that the CNC laser production method and the marquetry technique are adaptable to industrial mass production.
PubDate: 2023-06-01
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- Robustness of texture-based roundwood tracking
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Abstract: The proof of origin of wood logs is becoming more and more important. In the context of Industry 4.0 and to combat illegal logging, there is an increased interest to track each individual log. There were already previous publications on wood log tracing using image data from logs, but these publications used experimental setups that cannot simulate a practical application where logs are tracked between different stages of the wood processing chain, like e.g. from the forest to the sawmill. In this work, we employ image data from the same 100 logs that were acquired at different stages of the wood processing chain (two datasets at the forest, one at a laboratory and two at the sawmill including one acquired with a CT scanner). Cross-dataset wood tracking experiments are applied using (a) the two forest datasets, (b) one forest and the RGB sawmill dataset and (c) different RGB datasets and the CT sawmill dataset. In our experiments we employ two CNN based method, 2 shape descriptors and two methods from the biometric areas of iris and fingerprint recognition. We will show that wood log tracing between different stages of the wood processing chain is feasible, even if the images at different stages are obtained at different image domains (RGB-CT). But it only works if the log cross sections from different stages of the wood processing chain either offer a good visibility of the annual ring pattern or share the same woodcut pattern.
PubDate: 2023-06-01
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- Capacity models for timber under compression perpendicular to grain with
screw reinforcement-
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Abstract: This paper compares the performance of probabilistic and deterministic capacity models for reinforced timber members under compression perpendicular to the grain. A database collecting approximately 60 test results has been compiled by reviewing research papers and master’s and doctoral theses from the past twenty years. The capacity model proposed for the next generation of Eurocodes assesses the capacity as the minimum between the values associated with two failure modes, one at the contact plate and one at the screw tips. The main drawbacks of the model are the excessive elaborateness, given its limitation in accuracy and the fallacy in predicting the observed failure modes. In detail, the failure by the screw tips seldom occurs, although it was expected in more than half of the selected specimens. The authors attempted to simplify the capacity equation by proposing a generalized expression corresponding to the failure mode at the contact plate, corrected by a factor including the effects of load and screw arrangement and geometric details of the specimen. A deterministic mechanical model obtained by multiplying the timber strength by the contact area with a given coefficient performs better than the Eurocode model, which attempts to include the effect of load diffusion (R \(^2\approx 0.27\) ). A constant factor equal to 2 yields a suitable fitting (R \(^2\approx 0.76\) ). The best performance is achieved with a four-term polynomial, with adimensional addends, leading to an optimum fitting (R \(^2\approx 0.82\) ).
PubDate: 2023-06-01
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- Volatile organic compounds emitted from Scots pine and Norway spruce wood
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Abstract: Volatile organic compound (VOC) emissions from Scots pine and Norway spruce wood were evaluated in green and kiln-dried conditions using Micro-Chamber (µ-CTE™) air-sampling, thermal desorption, and GC–MS. A total of 411 specimens were tested to evaluate sampling distributions, effect of kiln drying, and the chemical composition of VOC emissions in detail. There was no significant difference in emissions between spruce heartwood and sapwood. The median total VOC emission rate from spruce was 93% lower than that from pine heartwood in green condition, whereas in the kiln-dried state, the emission was 98% lower. Compared with pine sapwood, the median emissions from spruce were 85% and 94% lower in green and kiln-dried conditions, respectively. Pine sapwood emitted 55% and 79% less VOC than heartwood in green and kiln-dried conditions. Except for pine sapwood, all groups exhibited positively skewed distributions. The skewness was particularly noticeable in the green pine heartwood sample, where the top 10% of VOC scores increased the mean VOC emission by 67%. Kiln drying had a substantial impact on VOC emissions. The median emission reduction due to drying amounted to 93%, 79%, and 80% for spruce, pine heartwood, and pine sapwood, respectively. A strong positive linear relationship was observed between the emissions in the green condition and the emission reduction caused by drying. Except for 3-carene, the emission profiles were similar among the tested groups.
PubDate: 2023-06-01
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- Assessing the information value of wood products perceived from young
consumers-
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Abstract: Taiwan has an extremely low wood self-sufficiency rate (< 1%) and the Forestry Bureau of Taiwan intends to revitalize forestry to alleviate it. A demand for domestic wood products can effectively increase Taiwan’s wood self-sufficiency rate, but how the demand can be increased is currently unknown. Most young consumers are highly educated and have stronger needs for wood product information. However, Taiwan presently lacks relevant surveys on various wood product information. Therefore, this study employed a questionnaire survey to explore young consumers’ views on assessing the value of domestic wood and wood products. This study addressed three issues: Which young consumer groups value the provision of wood product information' What wood product information is valued by which young consumer group' What information is required by young consumer groups when purchasing wood products' The analysis results showed that young consumers valued environmental friendliness, especially with sustainability certifications, of wood products. However, they held a neutral attitude towards the importance of domestic wood products versus imported wood and did not agree that domestic wood products have higher quality compared with imported ones. These results indicated that the government needs to continue promoting sustainable forest certifications to enhance young consumers’ trust in domestic wood products. Lastly, all subgroups of young consumers paid attention to the effects of additives. It is suggested that producers or suppliers should provide more information on wood product compositions and additives.
PubDate: 2023-06-01
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- Experimental assessment and numerical analysis of a shear specimen for
wood adhesive fiber composites-
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Abstract: This study investigated the shear strength of fiber reinforced polymer (FRP)-wood bonds based on the experimental results of a specific type of test specimen developed for this composition by directly comparing the strengths of bondline and solid wood of Picea abies Karst. species. Four types of fibers were used, three synthetic (Vectran, Carbon 300 and Carbon 600) and one natural (Sisal), bonded with two adhesives (polyurethane and epoxy). Carbon 300 and Sisal fibers showed better structural compatibility when bonded with epoxy resin, while Vectran and Carbon 600 presented similar compatibility when glued with epoxy or polyurethane resins. Numerical analysis was carried out in order to understand if the experimental procedure can influence the shear strength results for the different composites. It allowed assessing the stress distribution in the shear plane in terms of tangential and orthogonal stresses to the bond plane for different FRP elastic moduli and glue line thicknesses. The study observed high stress concentrations at the edges of the specimen and lower stresses in the middle of the shear area, both influenced by the elastic modulus and thickness. Numerical results showed that the presence of normal stress peaks increased as stiffness decreased and thickness increased. This occurrence may explain the better strength values observed experimentally for the high stiffness fiber-reinforced assemblies compared to pure adhesives or Sisal, which have low stiffness and high thickness.
PubDate: 2023-06-01
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- Effect of the temperature and grain direction on the stress relaxation
behavior of PCM-impregnated and nonimpregnated wood under tensile and
bending stresses-
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Abstract: Due to its anatomical properties, wood is an anisotropic, porous, and heterogeneous material with constituent cells of varying types and shapes. The time-dependent mechanical response of wood is of notable interest in structural applications, especially the viscoelastic response. This work characterized the viscoelastic response of Pinus radiata impregnated with a paraffinic phase change material (PCM; technical grade octadecane), thereby considering the longitudinal, radial, and tangential log directions. In addition, the effect of the temperature on the viscoelastic response was examined, evaluating the PCM in the solid (15 \(^\circ\) C) and liquid (35 \(^\circ\) C) states. The elastic moduli of all tested wood specimens indicated similar trends; the magnitude was the largest along the longitudinal direction, followed by the tangential and radial directions. In the solid PCM phase, the stress relaxation decreased along the longitudinal direction regarding liquid-phase PCM. Conversely, greater relaxation responses were observed along the radial and tangential directions in the presence of solid-phase PCM compared to a liquid-phase-impregnated sample. Finally, a nonlinear response was observed along the tangential direction during the relaxation tests, depending on the strain reached.
PubDate: 2023-06-01
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- Effect of drying processes and sampling positions on the microstructure
and physical–mechanical properties of NaOH-treated bamboo (Phyllostachys
pubescens) slivers-
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Abstract: Simple aqueous alkali treatment has proven effective in improving the mechanical properties and flexibility of bamboo slivers, yet the effects of drying methods on the structure and properties of alkali-treated bamboo slivers remain not fully explored. Here, we mainly examined the effects of three different drying processes, i.e., hot-air (50 °C for 8 h), microwave (600 W for 2 min), and freeze drying (− 50 °C for 72 h), on the appearance, microstructure, and physical and mechanical properties of bamboo slivers that were pretreated in the 5% NaOH solution for 2 h. The results showed that hot air- and microwave drying resulted in a similar structure of collapsed parenchyma cells, but many large gaps between the cells were generated by microwave drying. Freeze drying well preserved the original structure. According to statistical analysis, the increases in density, tensile strength, and tensile modulus of the hot air-dried bamboo slivers were more significant than that of microwave-dried and freeze-dried slivers. Compared with the untreated bamboo slivers, the density of hot air-dried outer- and inner bamboo slivers was increased by 28.5 and 49.0%, respectively; the tensile strength was increased by 55.7% and 99.4%, respectively; and the tensile modulus was increased by 76.8 and 36.9%, respectively. Regardless of the drying process, the flexibility of all bamboo slivers was considerably improved after drying. The outer bamboo slivers dried by microwave were found to have the highest flexibility, while hot air drying was found the most effective in improving the flexibility of the inner bamboo slivers. The excellent tensile and bending properties of hot air-dried bamboo slivers were mainly attributed to the fact that hot air drying was beneficial for forming more hydrogen bonds after the removal of lignin and hemicellulose in alkali treatment, resulting in tight aggregations of cellulose molecules. The dense connections between parenchyma cells induced by hot air drying allowed the formation of interlocking cell structures, leading to higher tensile strength and flexibility. It suggests that hot air drying, following the alkali pretreatment, is an effective drying method to modify bamboo slivers to be strong and flexible.
PubDate: 2023-06-01
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- Moisture desorption isotherms and thermodynamic properties of two dense
tropical woods: Tali (Erythrophleum suaveolens Brenan) and Bilinga
(Nauclea diderrichii Merr)-
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Abstract: The aim of this study was to determine moisture desorption isotherms and some thermodynamic properties of two dense tropical woods from Cameroon: Tali (Erythrophleum suaveolens) and Bilinga (Nauclea diderrichii), which are classified as medium-heavy (Bilinga) and heavy (Tali) woods with high economic values. Equilibrium moisture contents (EMC) were determined using the static gravimetric method at three temperatures (30 °C, 40 °C, 60 °C) and relative humidities (RH) between 5.5 and 83.6%. For thermodynamic properties, Gibbs free energy (GFE), net isosteric heat (qst,n) and differential entropy (ΔS) were determined using Clausius Clapeyron and Avramidis equations. To interpret hygroscopic behavior and thermodynamic properties, anatomical and chemical structures were analyzed using microscopic images and infrared (IR) spectroscopy respectively. EMC decreased from 19.39 to 1.99% for Bilinga and from 11.17 to 0.51% for Tali as temperature increased. GAB model best described desorption isotherms data. Desorption isotherms recorded type II sigmoids. Anatomical analysis revealed that Tali and Bilinga had porosities of 40.52 and 50.32%, 3–6 and 6–12 vessels/mm2, 400–700 µm and 700–1000 µm rays respectively. Specific Surface Areas (SSA) decreased from 155.602 to 57.115 m2/g for Tali and 287.692 to 175.688 m2/g for Bilinga. This result supports the isotherms measurement in terms of hygroscopic capacity of woods. Positive thermodynamic properties revealed that desorption was non-spontaneous and the difference between harmonic mean and isokinetic temperatures confirms an enthalpy-entropy compensation theory. qst,n is higher for Tali implying it is less hygroscopic and requires more energy than Bilinga.
PubDate: 2023-06-01
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- Essential oils from Thymus spp. as natural biocide against common brown-
and white-rot fungi in degradation of wood products: antifungal activity
evaluation by in vitro and FTIR analysis-
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Abstract: Use of wood products in bio-building is increasing because of the raw material’s sustainability and renewability. Degradation of wood by fungi is one of the most significant threats in the use of wooden structures. In the past, degradation was prevented by the application of wood preservatives or the use of durable tropical species. Therefore, wood preservation by fossil-based compounds and heavy metals is one of the major issues. This study evaluated the antifungal activity of four essential oils of thyme species (Thymus capitatus, Coridothymus capitatus, T. vulgaris, and T. vulgaris Demeter, collected from organic and biodynamic farms, respectively) against two white-rot fungi (Trametes versicolor and Pleurotus ostreatus) and two brown-rot fungi (Poria monticola and Gloeophyllum trabeum). The thyme varieties’ essential oils differed in their chemical composition, with either carvacrol, thymol or p-cymene as major components. All four essential oils showed good antifungal activities, in which T. capitatus was the most toxic when applied against P. monticola (MIC of 0.05) and the most efficient inhibiting the growth of the other fungal strains. Fourier transform infrared (FTIR) spectroscopy was applied to investigate fungal cell wall structure under control and stress conditions. The results are a further step towards more eco-friendly solutions for preserving less durable wood products more frequently used in bio-building.
PubDate: 2023-06-01
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- Towards circular economy by valorization of waste upholstery textile
fibers in fibrous wood-based composites production-
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Abstract: The aim of the research was to utilize textile waste by adding upholstery fabric fibers with different content (0, 5, 10, and 20% by weight referred to dry wood fibers) to high density fiberboards (HDF) and analyze selected physical and mechanical properties of the obtained boards. Tests of mechanical (modulus of elasticity in bending and bending strength, surface soundness, internal bond, screw withdrawal resistance) and physical (density profile, swelling in thickness after immersion in water, water absorption) properties were performed. The results show that the increasing content of textile fibers in HDF panels has the strongest negative influence on mechanical properties, especially internal bond, and screw withdrawal resistance. Modulus of elasticity and modulus of rupture also decreased, but still fulfilled the requirements of European standards. No significant influence of rising content of textile fibers on HDF thickness swelling and water absorption has been found. It can be concluded that, depending on further application of HDF, it is possible to utilize the recovered upholstery textile fibers as a reasonable addition to wood fibers when producing HDF panels. It is also a step toward carbon storage extension, which is fixed in textile fibers.
PubDate: 2023-06-01
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- Steaming or freezing improves decay resistance, copper leaching and
wood/copper interactions of micron CuO/silica sol treated poplar (Populus
tomentosa Carr.)-
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Abstract: Micro-based wood preservatives have tremendous potential for reducing in-service preservative losses thereby reducing the amounts needed for protection. Enhancing micro-based wood preservatives/wood interactions without negatively affecting performance could help further enhance the properties of these materials. The factors affecting the leaching and decay resistance of the micro CuO/silica sol wood preservative and the mechanism of action of the preservative and wood were analyzed using scanning electron microscopy/energy dispersive X-ray analysis, Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction for both steaming and freezing post-treatment. SEM showed that the preservative had an irregular spherical shape with an average diameter of 0.45 μm. Changes in moisture content and pH were factors affecting preservative leaching and blocks decay resistance. FTIR analysis showed that the interaction between preservative and wood occurred in wood cellulose and lignin, and freezing treatment enhanced this interaction, which was the reason why freezing treatment improved preservative leaching resistance.
PubDate: 2023-06-01
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- Research on the orthogonal cutting performance of polyethylene-based
wood-plastic composite based on principal component analysis-
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Abstract: In order to study the interaction between various cutting factors and obtain excellent machined quality in orthogonal cutting of polyethylene-based wood-plastic composites, this paper compared the cutting mechanism of WPC with the classical wood cutting mechanism and applied the principal component analysis method to model the cutting results to carry out a comprehensive analysis. The results showed that the cutting temperature was influenced by the cutting force, rake angle, and squeezing when the chip was removed. The cutting mechanism of the wood-plastic composite was quite different from that of wood; the chip shape of WPC was mainly segmental chip; the chip was torn and broken like a cantilever beam by the tool. The machined surface damage of WPC was similar to the wood cutting direction of 0–90. When chips form, they often drive the destruction of parts of the material below the cutting layer, thus creating pits on the machined surface. During rough machining of the wood-plastic composite material, the rake angle should be less than 20°. When finishing wood-plastic composite material, a larger rake angle would be better. The established principle component analysis model can comprehensively evaluate the cutting of wood-plastic composite materials and plays a significant role in the coupling analysis of multiple factors, the classification of influencing factors, and the comprehensive ranking of cutting quality.
PubDate: 2023-06-01
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- Particle tracking velocimetry as a method for chip ejection studies during
groove milling of particleboard-
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Abstract: Studies on chip ejection from tools provide important information for the design of tools and effective chip collection elements used in woodworking machines. Among the chip properties, chip motion and its distribution are of particular interest for the design process. Until now, chip velocities have only been measured by manual tracking over a high-speed image sequence, which allows only a small scope of inspection. Here, we present the use of high-speed imaging in combination with particle tracking velocimetry as a new method for the semi-automatic evaluation of the magnitudes and directions of chip velocities. The methodology was tested in groove milling of particleboard. It was found that state-of-the-art particle tracking algorithms are suitable for quantitative analysis of chip motion in high-speed images. Therefore, spatial and temporal analysis of the chip velocity along the tool circumference are feasible and are presented here. In addition to chip velocity, chip collisions with the tool or other chips can be observed. This research also shows that image evaluation of chip sizes and shapes is potentially possible. In summary, the presented work provides methods that can quantitatively describe chip motion after chip formation. The experiments indicate that with each tooth engagement, new chips are formed, which initially move into the chip space at a median velocity higher than the cutting speed. After collisions with the tool and interparticle collisions, the particles leave the chip space of the tool at lower speeds. The machining tests performed with different process settings showed differences in the analysis results of chip movement. In the future, the presented methodology offers the possibility of investigating the relationships between tooth and chip space geometries, as well as different materials and the chip ejection of tools. Thus, the presented methodology provides a basis for creating a more general understanding of chip motion from machining operations, which can lead to innovations and improvements in chip collection.
PubDate: 2023-06-01
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- Optimization of the ultrasound-assisted extraction for phenolic compounds
content and antioxidant activity of Cortex fraxini using response surface
methodology-
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Abstract: In this study, for the first time, optimized phenolic compounds and antioxidant properties were derived from the extraction process of Cortex fraxini (CFR) using response surface methodology. Four factors and three levels of Box-Behnken (BBD) were used to study the extraction time (X1), extraction temperature (X2), ethanol concentration (X3), and solvent-material ratio (X4). The analysis of variance (ANOVA) revealed that temperature and solvent-material ratio had a relatively large effect on the response. The optimal combination of phenolic compounds and antioxidant activity was obtained with the optimal conditions of X1 = 1.629 h, X2 = 53.367 ℃, X3 = 60.971% (v/v), and X4 = 45.582 mL/g under ultrasonic assisted extraction (UAE). The experimental parameters were consistent with the predicted values. Caffeic acid, erucic acid, ferulic acid and p-hydroxycinnamic acid and other 19 phenolic acids were characterized by high performance liquid chromatography-mass spectrometry (HPLC–MS). The results of this study indicate that optimization of the extraction process is essential for the accurately determined measurement of phenolic components and antioxidants in CFR for its industrial applications.
PubDate: 2023-06-01
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