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The Mg-2Sn-2Zn-0.7Mn-0.5Ca (wt.%) alloy was employed to investigate the effect of forging passes on both microstructural and mechanical properties as well as the mechanism of multidirectional forging (MDF). The results show that with the increase of MDF passes, the second phase is fragmented and dispersed. At the same time, the alloy's microstructure exhibits necklace-like microstructures with different thicknesses due to the generation of recrystallized grains. After the alloys are deformed by the first forging pass (MDF-1) and the third forging pass (MDF-3), both the strength and plasticity tend to increase. The strength of MDF-3 passes is the highest (230 MPa), while the elongation is improved in the fifth forging pass (MDF-5) deformed alloy with a concomitant decrease in tensile strength by 11 MPa. This phenomenon occurred because, after the alloy undergoes MDF-5 deformation, the texture changes from a typical basal texture to a bimodal texture. In other words, following MDF treatment, grain refinement and texture weakening together affect the mechanical properties of the alloys. [ABSTRACT FROM AUTHOR]

The chair-mounted passive trunk orthosis (CMPTO) is designed to enhance wheelchair safety for individuals with dystrophinopathy during their daily activities. Given the disease's progressive nature, it is crucial to ensure that assistive devices are carefully evaluated to prevent overexertion. This study aims to assess the CMPTO's user experience and its impact on fatigue-related psychophysiological measurements. We conducted electromyography (EMG) evaluations of four trunk muscles and assessed perceived exertion using the Borg CR-10 scale in 40 healthy subjects while they performed seated maximal reaching tasks with the CMPTO. Additionally, fifteen dystrophinopathy patients evaluated the CMPTO for usability with the System Usability Scale. Paired t-tests were employed to compare the median frequency (MDF) of EMG signals, the Wilcoxon signed-rank test for evaluating exertion, and the Mann–Whitney U test to compare the usability reported by patients to those of healthy subjects. The 4-way ANOVA revealed that MDF patterns were significantly influenced by task orientation for each muscle. The CMPTO did not cause a significant reduction in the MDF. Tasks requiring greater trunk rotation were perceived as more exhaustive. Patients reported acceptable usability with the CMPTO, with scores higher than those of healthy subjects. The CMPTO's usability was comprehensively evaluated in both healthy subjects and patients with dystrophinopathy. Our findings indicate that the CMPTO can be safely used by individuals with dystrophinopathy as an assistive device to improve seated comfort and functional abilities. [ABSTRACT FROM AUTHOR]

Medium-density fiberboard (MDF) waste generation has increased steadily over the past decades, and therefore, the investigation of novel methods to recycle this waste is very important. The potential of repurposing MDF waste as an adsorbent for the treatment of Cd(II), Cu(II), Pb(II), and Zn(II) ions in water was investigated using MDF offcuts. The highest adsorption potential in single-metal ion solution systems was observed for Pb(II) ions. The experimental data of Pb(II) ions fit well with the Freundlich isotherm and pseudo-second-order kinetic models. Complexation and electrostatic interactions were identified as the adsorption mechanisms. The adsorption behavior of multi-metal ion adsorption systems was investigated by introducing Cd(II) ions as a competitive metal ion. The presence of the Cd(II) ions reduced the adsorption potential of Pb(II) ions, yet the preference for the Pb(II) ions remained. Regeneration studies were performed by using 0.1 M HCl as a regeneration agent for both systems. Even though a significant amount of adsorbed metal ions were recovered, the adsorption potential of the MDF was reduced in the subsequent adsorption cycles. Based on these results, MDF fines have the potential to be used as an economical adsorbent for remediation of wastewater containing heavy metal ions. [ABSTRACT FROM AUTHOR]

Effects of adding different boron compounds to the urea-formaldehyde resin were evaluated relative to the physical, mechanical, and other properties of medium-density fiberboard (MDF). While the chemical addition of boric acid to the urea-formaldehyde resin increased the modulus of rupture and modulus of elasticity values of MDF boards, the physical and chemical additions of other boron compounds decreased those values. While there were no significant decreases in internal bond values, the chemical addition of boric acid and borax decahydrate to ureaformaldehyde resin increased the internal bond values of MDF boards. It was observed that in both types of addition, borax pentahydrate reduced the formaldehyde emission values of MDF boards the most and also reduced the burnt area by up to 30%. When the type of addition of boron compounds to urea-formaldehyde was compared, the addition of boron compounds at the resin formation stage showed better results in the properties of MDF boards than physical addition. [ABSTRACT FROM AUTHOR]

The effective and comprehensive utilization of forest resources has become the theme of the global "dual-carbon strategy". Forestry restructured wood is a kind of wood-based panel made of wood-based fiber composite material by high-temperature and high-pressure restructuring–molding, and has become an important material in the field of construction, furniture manufacturing, as well as derivative processing for its excellent physical and mechanical properties, decorative properties, and processing performance. Taking Medium Density Fiberboard (MDF) as the recombinant material as the research object, an event-triggered synergetic control mechanism based on interventional three-way decision making is proposed for the viscoelastic multi-field coupling-distributed agile control of the "fixed thickness section" in the MDF continuous flat-pressing process, where some typical quality control problems of complex plate shape deviations including thickness, slope, depression, and bump tend to occur. Firstly, the idea of constructing the industrial event information of continuous hot pressing based on information granulation is proposed, and the information granulation model of the viscoelastic plate shape process mechanism is established by combining the multi-field coupling effect. Secondly, an FMEA-based cyber granular method for diagnosing and controlling the plate thickness diagnosis and control failure information expression of continuous flat pressing is proposed for the problems of plate thickness control failure and plate thickness deviation defect elimination that are prone to occur in the continuous flat-pressing process. The precise control of the plate thickness in the production process is realized based on event-triggered control to achieve the intelligent identification and processing of the various types of faults. The application test is conducted in the international mainstream production line of a certain type of continuous hot-pressing equipment for the production of 18 mm plate thickness; the synergistic effect is basically synchronized after 3 s, the control accuracy reaches 30%, and the average value of the internal bond strength is 1.40, which ensures the integrity of the slab. Practical tests show that the method in the actual production is feasible and effective, with detection and control accuracy of up to ±0.05 mm, indicating that in the production of E0- and E1-level products, the rate of superior products can reach more than 95%. [ABSTRACT FROM AUTHOR]

This research focuses on the effect of mat water spraying on the production yield and the quality of medium density fiberboard (MDF) on an industrial scale at Arian Sina MDF Company. A total of 180 raw medium density fiberboard panels, each with dimensions of 3.66×1.83×0.016 m, manufactured by the company in 2018, have been used as the experimental samples. These samples have been produced under various conditions, including 3 different groups: 1 – without mat water spraying; 2 and 3 – with mat water spraying using 40 and 50 g/m² of water, correspondingly. Other parameters have included a constant adhesive content (10 % of dry fiber content), a fixed mat moisture content (7 %), and the use of poplar species (70 %) and Eucalyptus camaldulensis (30 %). Additionally, a hardener (at 0.8 % of the dry weight of glue) has been applied. The results have demonstrated that water spraying onto both sides of the mat increases the strength properties and improves the production yield. This enhancement is attributed to the reduced time required for transferring heat from the press plates to the core layer of the mat. Furthermore, X-ray vertical profile density analysis has indicated that water spraying onto the mat surface also increases the surface and core layer density of the panels.

Local agro-industrial wastes-based particleboards and fiberboards in Egypt are manufactured mainly from sugarcane-bagasse and flax shives. These panels are used in decorations and interior claddings. This paper aimed to broaden their market to be utilized in local low-cost and simple building envelope retrofitting packages instead of conventional packages that depend on imported expanded polystyrene and wet-rendered gypsum boards. Thermal conductivities of various existing sugarcane-bagasse and flax-shives-based panels were measured to be used in developing multilayered interior claddings with adequate thermal insulating performance to increase the thermal mass of a validated non-insulated case-study residential building as recommended by the Egyptian Code for Energy Efficiency of Residential Buildings. Models retrofitted using the developed cladding assemblies were simulated using Design Builder to determine their achieved annual energy savings and predict their profitability. Thermal conductivities of sugarcane-bagasse and flax-shives-based particleboards were lower than wood-based cladding panels, with the range of 0.05–0.1166 W/mK. Moreover, the thermal conductivities of sugarcane-bagasse fiberboard had the range of 0.0926–01,111 W/mK which is significantly lower than wood-based fiberboards. Simulation results showed that both models retrofitted, sugarcane bagasse-based and flax shives-based, achieved better energy savings, 5.07% and 5.04%, than the conventionally retrofitted model, 3.73%. Furthermore, the flax-shives-based model showed higher profitability, with positive income achieved in the 15th year, than a conventionally retrofitted model, achieved in the 20th year, and the sugarcane-bagasse-based model, achieved in the 19th year. Thus, it was recommended that although flax-shives-based wall claddings were usually 14–20% thicker than sugarcane-bagasse-based claddings, they provided similarly high annual energy savings with lower initial costs and higher profitability.

Local agro-industrial wastes-based particleboards and fiberboards in Egypt are manufactured mainly from sugarcane-bagasse and flax shives. These panels are used in decorations and interior claddings. This paper aimed to broaden their market to be utilized in local low-cost and simple building envelope retrofitting packages instead of conventional packages that depend on imported expanded polystyrene and wet-rendered gypsum boards. Thermal conductivities of various existing sugarcane-bagasse and flax-shives-based panels were measured to be used in developing multilayered interior claddings with adequate thermal insulating performance to increase the thermal mass of a validated non-insulated case-study residential building as recommended by the Egyptian Code for Energy Efficiency of Residential Buildings. Models retrofitted using the developed cladding assemblies were simulated using Design Builder to determine their achieved annual energy savings and predict their profitability. Thermal conductivities of sugarcane-bagasse and flax-shives-based particleboards were lower than wood-based cladding panels, with the range of 0.05-0.1166 W/mK. Moreover, the thermal conductivities of sugarcane-bagasse fiberboard had the range of 0.0926-01,111 W/mK which is significantly lower than wood-based fiberboards. Simulation results showed that both models retrofitted, sugarcane bagasse-based and flax shives-based, achieved better energy savings, 5.07% and 5.04%, than the conventionally retrofitted model, 3.73%. Furthermore, the flax-shives-based model showed higher profitability, with positive income achieved in the 15th year, than a conventionally retrofitted model, achieved in the 20th year, and the sugarcane-bagasse-based model, achieved in the 19th year. Thus, it was recommended that although flax-shives-based wall claddings were usually 14-20% thicker than sugarcane-bagasse-based claddings, they provided similarly high annual energy savings with lower initial costs and higher profitability. [ABSTRACT FROM AUTHOR]

The aim was to identify if surface electromyography (sEMG) parameters are indicative of post-activation potentiation (PAP)/post-activation performance enhancement (PAPE), in terms of twitch potentiation and voluntary performance. Three databases were used in April 2024, with the following inclusion criteria: (a) original research, assessed in healthy human adults, and (b) sEMG parameters were measured. The exclusion criteria were (a) studies with no PAP/PAPE protocol and (b) non-randomized control trials. The following data were extracted: study characteristics/demographics, PAP/PAPE protocols, sEMG parameters, twitch/performance outcomes, and study findings. A modified physiotherapy evidence database (PEDro) scale was used for quality assessment. Fifteen randomized controlled trials (RCTs), with a total of 199 subjects, were included. The M-wave amplitude (combined with a twitch torque outcome) was shown to generally be indicative of PAP. The sEMG amplitudes (in some muscles) were found to be indicative of PAPE during ballistic movements, while a small decrease in the MdF (in certain muscles) was shown to reflect PAPE. Changes in the Hmax/Mmax ratio were found to contribute (temporally) to PAP, while the H-reflex amplitude was shown to be neither indicative of PAP nor PAPE. This review provides preliminary findings suggesting that certain sEMG parameters could be indicative of PAP/PAPE. However, due to limited studies, future research is warranted. [ABSTRACT FROM AUTHOR]

A novel pretreatment strategy utilizing a combination of NaOH and 1-Butyl-3-methylimidazolium chloride ([Bmim]Cl) was proposed to enhance the enzymatic hydrolysis of abandoned Medium-density fiberboard (MDF). The synergistic effect of NaOH and [Bmim]Cl pretreatment significantly improved the glucose yield, reaching 445.8 mg/g within 72 h, which was 5.04 times higher than that of the untreated samples. The working mechanism was elucidated according to chemical composition, as well as FTIR, 13C NMR, XRD, and SEM analyses. The combined effects of NaOH and [Bmim]Cl led to lignin degradation, hemicellulose removal, the destruction and erosion of crystalline regions, pores, and an irregular microscopic morphology. In addition, by comparing the enzymatic hydrolysis sugar yield and elemental nitrogen content of untreated MDF samples, eucalyptus, and hot mill fibers (HMF), it was demonstrated that the presence of adhesives and additives in waste MDF significantly influences its hydrolysis process. The sugar yield of untreated MDF samples (88.5 mg/g) was compared with those subjected to hydrothermal pretreatment (183.2 mg/g), Ionic liquid (IL) pretreatment (406.1 mg/g), and microwave-assisted ionic liquid pretreatment (MWI) (281.3 mg/g). A long water bath pretreatment can reduce the effect of adhesives and additives on the enzymatic hydrolysis of waste MDF. The sugar yield produced by the combined pretreatment proposed in this study and the removal ability of adhesives and additives highlight the great potential of our pretreatment technology in the recycling of waste fiberboard. [ABSTRACT FROM AUTHOR]

The wood-based panel industry is experiencing an excessive accumulation of solid residues from the production of medium-density fiberboard (MDF) panels and moldings. It is possible to create new MDF products with acceptable physical and mechanical properties by revaluing MDF residues. Additionally, those products' thermal properties can be improved by incorporating phase change materials (PCMs). This study aims to develop a wood-based fiberboard made of MDF residues, capable of storing thermal energy. Two types of PCMs (liquid and microencapsulated), two PCM ratios (2% and 6%), and two types of adhesives (urea-formaldehyde and phenol-formaldehyde) were used to produce eight different types of panels. The vertical density profile, thickness swelling, water absorption, internal bond (IB), and static bending properties—modulus of elasticity (MOE) and modulus of rupture (MOR)—were determined for each panel type. The specific heat of the panels was also determined. The results show the panels' densities were greater than 700 kg/m3. Thickness swelling in water improved by 23% compared to the reference value of the control panel PCMs after PCM incorporation. The highest IB value was 1.30 MPa, which is almost three times the minimum required by regulation standards. The incorporation of PCMs reduced the panels' bending properties compared to the properties of the control panels. Even though the values obtained are sufficient to comply with the minimum values set out in ANSI standard A208.2 with an MOE value of 2072.4 MPa and the values obtained are sufficient to comply with the minimum standards with an MOE value of 2072.4 MPa and an MOR value of 16.4 MPa, when microencapsulated PCM is used, the specific heat of the panels is increased by more than 100% over that of the control panels. This study developed fiberboards with adequate physical and mechanical properties and capable of storing thermal energy. [ABSTRACT FROM AUTHOR]

Multisensor data fusion (MDF) is a process/technique of combining observations from multiple sensors to provide a more robust, accurate and complete description of the concerned object, environment or process. In this paper we introduce a new MDF method, multisensor optimal data fusion (MODF), to fuse different operational sea ice observations around Svalbard. The overall MODF includes regridding, univariate multisensor optimal data merging (MODM), multivariate check of consistency, and generation of new variables. For MODF of operational sea ice observations around Svalbard, the AMSR2 sea ice concentration (SIC) is firstly merged with the Norwegian Meteorological Institute ice chart. Then the daily SMOS sea ice thickness (SIT) is merged with the weekly CS2SMOS SIT to form a daily CS2SMOS SIT, which is further refined to be consistent with the SIC through consistency check. Finally sea ice volume (SIV) and its uncertainty are calculated based on the merged SIC and fused SIT. The fused products provide an improved, united, consistent and multifaceted description for the operational sea ice observations, they also provide consistent descriptions of sea ice edge and marginal ice zone. We note that uncertainties may vary during the regridding process, and therefore correct determination of the observation uncertainties is critically important for MDF. This study provides a basic framework for managing multivariate multisensor observations. [ABSTRACT FROM AUTHOR]

Iso-amyl ester rosin was synthesized and investigated for its potential utilization in medium density fiberboard (MDF) production. The isoamyl alcohol, the main starting material for the synthesis of isoamyl ester rosin, was obtained through the fractional distillation of fusel oil, a byproduct of bioethanol production. The optimum condition for the iso-amyl ester rosin synthesis was determined as: rosin (165 mmol), isoamyl alcohol (413 mmol), P-TSA/rosin 1.5% (w/w), and commercial additive/rosin 0.15% (w/w). The esterification reaction was followed by FT-IR and mass analysis. For MDF production, a water-repellent material, commercial paraffin (1.5% w/w relative to the dry fiber weight), iso-amyl ester rosin (1.5% and 2.0%; w/w), and unmodified rosin (1.5% and 2.0% w/w) were separately used. In addition, fresh wood fibers, 10% w/w urea formaldehyde (UF) adhesive (relative to the total dry fiber weight), and a 25% aqueous solution of ammonium chloride (as the hardening agent for the UF adhesive, at 0.5% w/w based on the solid adhesive content) were used. MDFs underwent various physical and mechanical tests. Isoamyl ester rosin showed promising results based on the analysis. The results showed that the isoamyl ester rosin can be considered as an alternative to paraffin in sustainable and environmentally friendly MDF production. [ABSTRACT FROM AUTHOR]

In many cases, flood frequency analysis (FFA) needs to be carried out on mean daily flows (MDF) instead of instantaneous peak flows (IPF), which can lead to underestimation of design flows. Typically, correction methods are applied to the MDF data to account for such underestimation. In this study, we first analyse the error distribution of MDF-derived flood quantiles over 648 catchments in Germany. The results show that using MDF instead of IPF data can lead to underestimation of the mean annual peak flow (MHQ) by up to 80 % and mainly depends on the catchment area but appears to be influenced by gauge elevation as well. This relationship is shown to differ for summer vs. winter floods. To correct such underestimation, different linear models based on predictors derived from MDF hydrograph and catchment characteristics are investigated. Apart from the catchment area, a key predictor in these models is the event-based ratio of flood peak to flood volume (p/V ratio) obtained by the MDF data. The p/V models applied to either MDF-derived events or statistics seem to outperform other reference correction methods. Moreover, they require a minimum data input, are easily applied, and are valid for the entire study area. The best results are achieved when the L moments of the MDF maximum annual series are corrected with the proposed model, which reduces the flood quantile errors by up to 60 %. The approach behaves particularly well in smaller catchments (<500 km 2), where reference methods fall short. However, the limit of the proposed approach is reached for catchment sizes under 100 km 2 , where the hydrograph information from the daily series is no longer capable of approximating instantaneous flood dynamics and gauge elevations below 100 m, where the difference between MDF and IPF floods is very small. [ABSTRACT FROM AUTHOR]

Iso-amyl ester rosin was synthesized and investigated for its potential utilization in medium density fiberboard (MDF) production. The isoamyl alcohol, the main starting material for the synthesis of isoamyl ester rosin, was obtained through the fractional distillation of fusel oil, a byproduct of bioethanol production. The optimum condition for the iso-amyl ester rosin synthesis was determined as: rosin (165 mmol), isoamyl alcohol (413 mmol), P-TSA/rosin 1.5% (w/w), and commercial additive/rosin 0.15% (w/w). The esterification reaction was followed by FT-IR and mass analysis. For MDF production, a water-repellent material, commercial paraffin (1.5% w/w relative to the dry fiber weight), iso-amyl ester rosin (1.5% and 2.0%; w/w), and unmodified rosin (1.5% and 2.0% w/w) were separately used. In addition, fresh wood fibers, 10% w/w urea formaldehyde (UF) adhesive (relative to the total dry fiber weight), and a 25% aqueous solution of ammonium chloride (as the hardening agent for the UF adhesive, at 0.5% w/w based on the solid adhesive content) were used. MDFs underwent various physical and mechanical tests. Isoamyl ester rosin showed promising results based on the analysis. The results showed that the isoamyl ester rosin can be considered as an alternative to paraffin in sustainable and environmentally friendly MDF production.

Chitosan and bio-based epoxy resins have emerged as promising formaldehyde-free replacements for traditional urea–formaldehyde (UF) adhesives in engineered wood products. This study evaluated five chitosan-to-epoxy weight ratios (3:1, 2:1, 1:1, 1:2, 1:3) as adhesives for hot-pressing medium density fiberboards (MDF) using mixed hardwood fibers. Increasing the epoxy ratio reduced viscosity and gel time, facilitating spraying and fast curing. The density of the formulated MDFs increased with higher epoxy ratios, ranging from 679 kg/m3 for the 3:1 ratio to 701 kg/m3 for the 1:3 formulation, meeting the 500–900 kg/m3 density range specified in EN 323. The 1:3 epoxy-rich formulation enhanced modulus of rupture (MOR) to 31 MPa and modulus of elasticity (MOE) to 2392 MPa, exceeding the minimum requirements of 16 MPa and 1500 MPa set out in EN 310 and EN 316, respectively. Dimensional stability peaked at 5% thickness swelling for the 1:3 formulation after 24 h water soaking, fulfilling the < 25% requirement per EN 316. Internal bond strength reached a maximum of 0.98 MPa for the 3:1 chitosan-rich formulation, satisfying the 0.40 MPa minimum per EN 319. One-way ANOVA tests showed the adhesive ratio had a significant effect on mechanical properties and dimensional stability at 95–99% confidence levels. Duncan's multiple range test revealed the 1:3 ratio boards exhibited statistically significant improvements compared to untreated group. Overall, tailoring the ratios achieved well-balanced properties for MOR, MOE, and dimensional stability, demonstrating potential to replace UF resins. [ABSTRACT FROM AUTHOR]

Wood waste, which constitutes an important component of solid waste, is produced by the wood industry, and especially in the processing one. The wood industry includes tree bark, sawdust, planer shavings, sander dust etc. produces unwanted products and/or wastes. This study investigated the usability of sawdust of fruit trees in the production of Medium Density Fiberboard (MDF) and some technological properties of the produced MDF panels. Sawdust of fruit trees was mixed to beech fibers at the ratio of 10, 20 and 30% by weight. The mats were manually formed using 13% urea formaldehyde and pressed at a temperature of 185°C for 8 min in a computer control press. The MDF panel samples of water absorption (WA), thickness swelling (TS), surface hardness, surface roughness, MOR and MOE were investigated. It was determined that the values of WA and TS decreased with increasing the ratio of sawdust. Modulus of rupture (MOR), modulus of elasticity (MOE), surface hardness, surface roughness parameters (Ra, Rq and Rz) values of panel samples increased with increasing the ratio of sawdust from panels. Based on these results, it is advisable that wood sawdust fruit-trees can be used as an alternative raw material source in MDF production. [ABSTRACT FROM AUTHOR]

Superlight Mg-10Li-3Al-3Zn (LA103Z) alloy cabins were fabricated by the integration of multi-directionally forging (MDF), die forging, and annealing treatment. α-Mg, β-Li, AlLi, MgLi2Al, and Mg17Al12 phases are detected in the as-cast alloy. Dynamic precipitation dominates during MDF and the relatively randomized macro-texture endows the MDFed billet with quasi-isotropic tensile properties. During subsequent compression, the grain growth and phase dissolution tend to occur with the decline of Zener–Hollomon parameter. The cabin die-forged at 260 °C and 6 mm/s owns the superior strength compared with the other cabins, which should be attributed to the sufficient dissolution of AlLi phases, fine grain size, reasonable amount and distribution of MgLi2Al particles, etc. Further annealed at 245 °C for 3 h, the above cabin exhibits the optimal comprehensive mechanical properties with the tensile yield strength (TYS) of 211 MPa, ultimate tensile strength (UTS) of 243 MPa, and elongation of 20.0%. This work provides a feasible way for industrial production of high-performance large-scale Mg-Li components. [ABSTRACT FROM AUTHOR]

In this study, the effect of successive hot and cold multi-directional forging (MDF) on the mechanical properties of the Al-9Si-0.6Mg-0.1Sr alloy was explored. The alloy was first homogenized and then forged at 200°C from 3 to 15 passes. After each three passes of hot forging, the samples were then cold forged up to three passes at room temperature. The microstructural examinations were carried out with X-ray diffraction technique and scanning electron microscopy equipped with energy-dispersive spectroscopy while mechanical properties were determined by tensile, compression and hardness tests. The hard particles were fragmented and began to distribute homogeneously into the matrix with increasing pass number of hot MDF. The yield, tensile and compressive strengths of the alloy reached to their maximum values at three passes of hot MDF along with hardness, above which they decreased, while its ductility exhibited a reverse trend. The cold MDF significantly increased the mechanical properties of initially hot MDFed samples. The nine passes in hot MDF were determined as the optimum pass number for obtaining the highest yield and tensile strength after cold MDF. These findings were evaluated according to dislocation strengthening, recrystallization and morphology of hard particles. [ABSTRACT FROM AUTHOR]

This research work is focused on the development of an alternative method for manufacturing Wood Plastic Composite (WPC) panels based on Wood Veneers (WVs) and High-Density Polyethylene (HDPE) through compression molding, which enhances the physical properties, particularly, water absorption and moisture content. The aim of the present research was to develop alternative panels to replace commercial ones, which are heavily affected by hot, humid climates. In this context, the study began with the design process, which consisted of the collection and processing of primary material, production of the additional components necessary for the manufacturing process, determination of the WV ratio, and preparation of the samples. Thereafter, physical and mechanical tests were carried out on WPC, HDPE (control), commercial gypsum boards (GBs), plywood (PW), and medium density fiberboard (MDF) samples. The results indicate that the method applied to manufacture the WPC samples improved physical properties, achieving a water uptake of less than 4% in both proportions of replacement tested, in contrast to commercial panels, which reached values between 10% and 40%. In addition, a greater load capacity was achieved for lower thick elements. [ABSTRACT FROM AUTHOR]

In order to improve the decorative properties of Magnesium-Glass-Board (MGB), the surface morphology and decoration performance of MGB, are studied in detail by using profilometer, microscope and SEM, and the influence of its characterization, such as surface roughness, surface porosity and wettability, on decorative properties of MGB is analyzed by comparing with medium density fiberboard (MDF) and medium density particleboard (MDP). The results first showed that the surface of MGB has a porous structure, but MDF and MDP are not, resulting in a poor decorative performance of MGB. Second, it is found that the surface wettability of MGB is better than others. Third, the hot-pressing parameters including pressure, temperature and time have different influence on decorative performance of MGB during hot-pressing experiment. Finally, the surface bonding strength is positively correlated with pressure, but not with temperature and time. In general, a higher surface bonding strength led to a better decorative performance of MGB. The furthermore research can concentrate on the modification method of the MGB's surface according to this paper's conclusion to improve the lamination performance of melamine paper. [ABSTRACT FROM AUTHOR]

Milling wood-based materials on CNC devices causes the creation of chips in small sizes that may escape the chip extraction zone to the surrounding environment and pollute the air. The article studied the effect of the feed rate (vf) and the width of cut (ae), transformed into kinematic average chip thickness, on the amounts of chips in respirable sizes <10.0μm created in the cutting zone from particleboards (PB) and medium-density fibreboards (MDF). The amounts of dust-sized chips are discussed and were determined by the sieving analysis. The sizes of potentially respirable chips were estimated by weighting with the laser diffraction method. The highest amounts of chips from PB were of 0.250-0.500 mm (38-41%w), but in MDF, amounts varied depending on cutting conditions. With (ae) 1 mm were in the size range of 0.125-0.250 mm (35-54%w), for (ae) 2 mm (33-35%w), and (ae) 3 mm (36-40%w) with combinations of (vf) 6-8 m·min-1. With a combination of (vf) 10 and 12 m·min-1 distribution moved to a higher size range. Chips in sizes 10.0-4.0 μm were estimated by <1%, for 4.0-2.5 μm <0.5%, in 2.5-0.1 μm <0.3%, and <0.1 μm by <0.05%. Statistically was proven (p<0.05) only in PB, with adjusted (ae) by 1 mm, increasing the value of (vf) from 6 to 12 m·min-1 and also with (vf) at 6 m·min-1, between values of (ae) 1 and 2 mm (hm of 0.025-0.035 mm), will significantly (p<0.05) lower the percentual amounts of chips in sizes 10.0-4.0 and 4.0-2.5 μm. [ABSTRACT FROM AUTHOR]

An Image Processing Based Scrub Tester (IPBST) was used to imitate the effect of household chemicals on furniture and decoration elements. For this purpose, 8 mm-thick, bright white, acrylic coated medium density fiberboard (MDF), polyvinyl chloride coated MDF, MDF lam ready-to-use sheets, and cellulosic, polyurethane, acrylic, and water-based paint applied MDF sheets were used. Carbon fiber patterned decorative coating was applied to the prepared sample surfaces using the water transfer printing and ultraviolet printing methods. The surfaces of the samples were scrubbed with various household chemicals in accordance with the Turkish Standard TS EN ISO 11998. In the image processing phase, the images before and after scrubbing were first converted to hue, saturation, and value color space. The relationship between the abrasion measurement method of the proposed IPBST and the abrasion data obtained from the stereo microscope device was examined using the Pearson Correlation analysis. The relationship between both abrasion test methods was positive, very strong, and significant (0.81). Thus, the IPBST can be used as an alternative to industrial test devices as it obtains similar data. [ABSTRACT FROM AUTHOR]

This study focuses on investigating the effect of Mg and Si content in different ratios on the microstructure evolution and superplasticity after processing by multidirectional isothermal forging of the Al–Mg–Si–Cu based alloys with additions of Fe and Ni forming large particles of phases of crystallization origin and dispersoid-forming elements Sc and Zr. The study examined alloys with the following Mg/Si content: 1.2/0.4 (3), 1.2/0.7 (1.7), and 2.0/0.7 (2.8) (wt %). The alloys underwent six cycles of isothermal multidirectional forging (MDF) at a temperature of 325°C with cumulative deformation of up to ∑ε = 14.4. During the MDF process, fragmentation occurred in particles of Mg2Si and Al9FeNi eutectic phases, resulting in the formation of particles with sizes of 0.6–0.7 and 1.2–1.5 µm, respectively. Due to particle stimulated nucleation mechanism and suppressed grain growth by nanoscale dispersoids the finegrained structure with a mean grain size of 2 μm was formed in alloys. An increase in Si concentration at constant Mg content, as well as an increase in Mg and Si concentration at a close Mg/Si ratio leads to an increase in fraction of recrystallized grains and a decrease in grain size after MDF. The alloy with the lowest Mg and Si content has shown the highest elongation under superplastic deformation, which is explained by the reduced fraction of Mg2Si phase particles of crystallization origin. [ABSTRACT FROM AUTHOR]

Microstructural evolution and the mechanical properties of recently developed lightweight AA2050 Al-Cu-Li alloy have been presented. A processing route of multi-directional forging (MDF) at 170 °C followed by artificial aging at 150 °C was employed. Systematic EBSD analysis revealed significant grain refinement with grain size reducing from 74.3 ± 12 to 22.1 ± 2.8 µm after 12 passes of MDF. Transformation of deformation bands into subgrains with dynamic recrystallization has led to grain refinement. TEM results show the presence of large dislocation clusters and deformation bands in MDF processed samples with a large number of fine precipitates in peak aged MDF processed samples. XRD analysis shows variation in peak intensities and occurrence of peak shifts due to induced lattice strain upon MDF. A substantial increase in microhardness and strength was observed with a minor trade-off with ductility after 12th MDF pass. Further, enhancement in strengths and microhardness were observed in post-MDF aged samples. Experimental results show the combined effect of strain hardening, grain size reduction, and precipitate hardening which influence the material strength. A combination of MDF and artificial aging has shown great potential to enhance the strength and ductility of AA2050. [ABSTRACT FROM AUTHOR]

The veneering process significantly affects the roughness of the furniture elements. The article investigates the effect of the veneering mode on the roughness of cherry (Prunus avium L.) veneered wood medium-density fiber boards (MDF). Different veneering regimes were carried out with controllable variation of the mode factors temperature and pressing pressure. For this purpose, a two-factor experiment was performed with a change in temperature of pressing from 80 to 200°C and pressure from 0.07 to 0.19MPa. Before venneering process, the veneered surfaces are sanded with P150 sandpaper. The values of basic roughness parameters were measured after each technological treatment, in the same evaluation lengths. Based on the results, graphical dependences between the roughness of the veneered boards and the basic mode parameters are presented. The press pressure does not significantly affect the roughness of the veneer. The combination of high temperature and high press pressure reduced initial surface roughness by 16%. [ABSTRACT FROM AUTHOR]

This study investigated the dissolved oxygen (DO) variation pattern in a Litopenaeus vannamei recirculating aquaculture system (RAS) and established an oxygen-utilization rate (UROxygen) model, pure oxygen addition (QOxygen) model, and control model that linked a microscreen drum filter (MDF) with a U-tube oxygenator. The main objective was to promote the application of the U-tube oxygenator and achieve the efficient, accurate, and automated management of DO in an RAS. To avoid wasting oxygen and ensure production safety, it was recommended to maintain the effluent of the aquaculture pond at 6.9 ± 0.4 mg/L. The modeled relationship between the RAS flow (QRAS), QOxygen, and UROxygen was UROxygen = 0.9626 × (−105.3406 + 0.9911QRAS + 10.6202QOxygen − 0.05964QRASQOxygen − 1.2628 × 10−3QRAS2 − 0.1821QOxygen2 + 6.8888 × 10−5QRAS2QOxygen + 6.3993 × 10−4QRASQOxygen2). The modeled relationship between QRAS, daily feeding rate (MFeeding), and QOxygen was QOxygen = 1.09 × (−12.8633 − 0.02793QRAS + 0.9369 MFeeding − 8.9286 × 10−4MFeedingQRAS + 5.6122 × 10−5QRAS2 − 2.3281 × 10−3MFeeding2). The modeled relationship between the MDF backwashing period (TMDF) and QOxygen was QOxygen = −11.57ln(TMDF) + 78.319. This study provided a theoretical basis and novel methods for the management of DO in an RAS, thus promoting the healthy and stable development of an L. vannamei RAS. [ABSTRACT FROM AUTHOR]

In a context where there is an increasing need for thermal treatments of wooden products, the current research contributes a description of the torrefaction treatment of two of the composite wood materials available on the international market. The present paper presents the importance of the torrefaction process for poplar plywood and medium-density fiberboard. In this paper, the positive aspects of the torrefaction process (decrease in water absorption, thickness swelling and shrinkage, and color) but also the negative aspects of mechanical resistance to static bending are presented. Poplar plywood (PW) and medium-density fiberboard (MDF) panels, with the initial dimensions of 2000 × 1250 mm, were used. From these, 300 × 300 mm samples were cut and torrefied using two different temperatures (170 and 190 °C) and two different periods (for 1 and 2 h). After the treatment, the samples were cut in different sizes (as necessary for each type of evaluation method) from different zones of the panels and used to evaluate the water absorption and thickness swelling, to determine their modulus of rupture, roughness, and color changes. The obtained results emphasize that the mass loses increase at high temperature as the main disadvantageous characteristics of torrefaction. Also, while the calorific power increases with the increase in the parameters of the torrefaction regime, the hygroscopicity and some mechanical properties of the material simultaneously decrease. [ABSTRACT FROM AUTHOR]

Most of the parts of furniture made of medium density fiberboards (MDF) require at least one hole to be assembled. The drilling technological parameters influence the quality of holes. Factors such as tip angle of the drill bit, feed rate, type and diameter of the drill bit, and spindle rotational speed could affect the drilling process. Therefore, the right choosing of drilling parameters is a mandatory condition to improve the drilling efficiency that is expressed through tool durability, cost, and quality of the drilling. Thus, in this work, we are proposed an approach that consists in combining two modelling techniques, which were successfully applied in various fields, namely artificial neural network (ANN) and response surface methodology (RSM), to analyze and optimize the drilling process of MDF boards. Four artificial neural network models with a reasonable accuracy were developed to predict the analyzed responses, namely delamination factor at inlet, delamination factor at outlet, thrust force, and drilling torque. These models were used to complete the experimental design that was requested by the RSM. The optimum values of the selected factors and their influence on the drilling process of the MDF boards were revealed. A part of optimum combinations among analyzed factors could be used both during the drilling of the MDF boards and prelaminated wood particleboards. [ABSTRACT FROM AUTHOR]

Melamine-impregnated paper decorated medium-density fiberboard (MIPMDF) is the main board used for wooden furniture materials in China, and the formaldehyde released from the board and furniture products is harmful to human beings and is a wide concern. This paper aimed to pay attention to the formaldehyde emission of MIP-MDF and its furniture products. This study utilized a 1 m³climatic chamber to measure the formaldehyde emission of MIP-MDF and nightstand made of MIP-MDF in relation to the time and load factors. According to the results, in the 2 to 24 h stage, the emission of formaldehyde in the nightstand made of MIPMDF materials changed significantly, and the overall trend showed a changing trend of first increasing and then declining. The formaldehyde emission of MIP-MDF stabilized after 40 h, while the formaldehyde emission of the nightstand stabilized after 60 h. As time passed, the formaldehyde emission changes of MIP-MDF and nightstand were almost the same. The formaldehyde emission of MIP-MDF and nightstand has a specific positive correlation with the carrying load. With increased carrying loads, the formaldehyde emission tends to increase, but the degree of influence gradually decreases with the addition of the carrying loads. [ABSTRACT FROM AUTHOR]

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Softwoods are the basic and traditional raw materials for medium-density fiberboard production. However, sustainable consumption of wood material in the production of wood-based products requires material variety. Therefore, the usability of hardwood species in the production and its effects on the board properties should be of interest. Considering this, the influence of oak utilization percentages (30 %, 50 %, 70 %, and 100 %) on the physical (density, thickness swelling-TS 2 and 24 h) and mechanical (modulus of rupture, modulus of elasticity, internal bonding, screw holding resistance, and Janka hardness) properties of medium density fiberboard was evaluated in this study. Boards were factory-made instead of laboratory-made using Quercus petraea (oak), Fagus orientalis (beech), and Pinus sylvester (Scots pine) fibers. According to the results, the modulus of rupture, modulus of elasticity, and Janka hardness values were increased when medium-density fiberboard was produced using only oak fiber. On the contrary, thickness swelling, screw-holding resistance, and internal bonding properties were decreased.

This paper presents a study on the accuracy of the width of the groove channel depending on the magnitude of the mechanical vibrations. Wood-based parts, used in furniture production like plywood and medium-density fiberboard (MDF) were milled. The details are machined on a universal milling machine with bottom location of the working shaft model FD-3. The rotation frequency used for the experiments was 6000min-1 . During the research, attention is paid to some technological factors such as the feed speed of the processed material which is from 2m.min-1 to 10m.min-1, as well as milling area which ranges is from 48mm2 to 144mm2 . Measurements of the accuracy of the groove channel are made with an electronic caliper at a minimum of three points along its length. The investigation results can be used as a base for making some recommendations for the selection of technological factors. [ABSTRACT FROM AUTHOR]

To investigate an impact of microcapsules on water-based coatings for a medium density fiberboard (MDF), three types of aloe emodin microcapsules prepared at a 3.0% concentration of SDBS, OP-10 and TWEEN-80 emulsifiers were added to the water-based coatings and applied on a MDF surface. Then, three sets of coatings were tested. Antibacterial properties of three groups of coatings on MDF surface increased with the addition of aloe emodin microcapsule content, and antibacterial properties of the water-based coating against Escherichia coli in the three groups were slightly superior to that of Staphylococcus aureus. The water-based coatings on the MDF surface with SDBS as the emulsifier showed the highest antibacterial rates of 74.1% and 66.0% against Escherichia coli and Staphylococcus aureus, respectively. The antibacterial rates of 70.0% and 62.8% were achieved for the OP-10 emulsifier group, and 67.0% and 61.9% for the TWEEN-80 emulsifier group, respectively. The aloe emodin microcapsules prepared at a 3.0% concentration of SDBS, OP-10 and TWEEN-80 emulsifiers inhibit bacterial growth and improve the mechanical and optical properties of coatings. It supplies technical references for the utilization of aloe emodin microcapsules to the antibacterial coating on the surface of wooden furniture. [ABSTRACT FROM AUTHOR]

Wood-based composites are increasingly used in the industry not only because of the shortage of solid wood, but above all because of the better properties, such as high strength and aesthetic appearance compared to wood. Medium-density fiberboard (MDF) is a wood-based composite that is widely used in the furniture industry. In this work, an attempt was made to predict the surface roughness of the machined MDF in the milling process based on acceleration signals from an industrial piezoelectric sensor installed in the cutting zone. The surface roughness parameter Sq was adopted for the evaluation and measurement of surface roughness. The surface roughness prediction was performed using a radial basis function (RBF) artificial neural network (ANN) and a Takagi–Sugeno––Kang (TSK) fuzzy model with subtractive clustering. In the research, as inputs to the ANNs and fuzzy model, the kinematic parameters of the cutting process and selected measures of the acceleration signal were adopted. At the output, the values of the surface roughness parameter Sq were obtained. The results of the experiments show that the surface roughness is influenced not only by the kinematic parameters of the cutting, but also by the vibrations generated during the milling process. Therefore, by combining information on the cutting kinematics parameters and vibration, the accuracy of the surface roughness prediction in the milling process of MDF can be improved. The use of TSK fuzzy modelling based on the subtractive clustering method for integrating the information from many acceleration signal measurements in the examined range of cutting conditions meant the surface roughness was predicted with high accuracy and high reliability. With the help of two tested artificial intelligence tools, it is possible to estimate the surface roughness of the workpiece with only a small error. When using a radial neural network, the root mean square error for estimating the value of the Sq parameter was 0.379 μm, while the estimation error based on fuzzy logic was 0.198 μm. The surface of the sample made with the cutting parameters vc = 76 m/min and vf = 1200 mm/min is characterized by a less concentrated distribution of ordinate densities, compared to the surface of the sample cut with lower feed rates but at the same cutting speed. The most concentrated distribution of ordinate density (for the cutting speed vc = 76 m/min) is characterized by the surface, where the feed rate value was vf = 200 mm/min, with 90% of the material concentrated in the profile height of 28.2 μm. When using an RBF neural network, the RMSE of estimating the value of the Sq parameter was 0.379 μm, while the estimation error based on fuzzy logic was 0.198 μm. [ABSTRACT FROM AUTHOR]

The study aims to investigate the influence of fraction of coarse undeformed particles on the microstructure evolution and mechanical properties of alloys processed by isothermal multidirectional forging (MDF). For this purpose, Al-Mg-Ni-Sc-Zr-based alloys with different Ni concentrations and a fraction of Al3Ni particles of solidification origin phase were subjected to MDF at 350 °C. Precipitates of the L12-structured Al3(Sc,Zr) phase retained their structure, morphology, and size after MDF and were coherent with the aluminum matrix. The Al3Ni phase particles stimulated the nucleation of recrystallized grains and contributed significantly to the formation of an ultrafine-grained structure. The uniformity of the grain structure increased, and the average grain size decreased with an increase in the fraction of Al3Ni particles. A fine-grained structure with a mean grain size of 2.4–3.4 µm was observed after MDF with a cumulative strain of 12. The results demonstrate that a bimodal particles size distribution with a volume fraction of nanoscale f~0.1% and microscale f~8% particles provided for the formation of a homogenous fine-grained structure after MDF and improved the mechanical properties. [ABSTRACT FROM AUTHOR]

The study aimed to increase the screw withdrawal strength of medium density fiberboard and particleboard used in furniture strength by using epoxy resin in the screw pilot hole. Therefore, the effects of pilot hole diameters, screw diameter, and amount of epoxy resin on screw withdrawal strength of medium density fiberboard and particleboard from face and edge were investigated. According to TS EN 13446, 50 mm × 50 mm specimens were cut from commercial medium density fiberboard and particleboard boards. A static load was applied parallel to the screw direction. The screw withdrawal strength of medium density fiberboard was higher than the screw withdrawal strength of particleboard because of its density. Besides, the screw withdrawal strength of medium density fiberboard and particleboard samples with a 3.5 mm screw diameter was higher compared to those with a 4.5 mm screw diameter. A decrease in pilot hole diameter and an increase in the amount of epoxy resin provided higher screw withdrawal strength of materials. Using 20 % epoxy resin of the volume of the pilot hole resulted in two times better screw withdrawal strength values. The study showed that a higher amount of epoxy resin, smaller pilot hole diameter, and smaller screw diameter contribute to better screw withdrawal strength of both medium density fiberboard and particleboard from the face and edge.

This study presents an unexplored method to produce formaldehyde-free MDF. Steam exploded Arundo donax L. (STEX-AD) and untreated wood fibers (WF) were mixed at different mixing rates (0/100, 50/50, and 100/0, respectively) and two series of boards were manufactured, with 4 wt% of pMDI, based on dry fibers, and self-bonded. The mechanical and physical performance of the boards was analyzed as a function of the adhesive content and the density. The mechanical performance and dimensional stability were determined by following European standards. The material formulation and the density of the boards had a significant effect on both mechanical and physical properties. The boards made solely of STEX-AD were comparable to those made with pMDI, while the panels made of WF without adhesive were those that performed the worst. The STEX-AD showed the ability to reduce the TS for both pMDI-bonded and self-bonded boards, although leading to a high WA and a higher short-term absorption for the latter. The results presented show the feasibility of using STEX-AD in the manufacturing of self-bonded MDF and the improvement of dimensional stability. Nonetheless, further studies are needed especially to address the enhancement of the internal bond (IB). [ABSTRACT FROM AUTHOR]

This study aimed at the application of unmodified (G) and modified graphite (EG) materials as a multifunction additive to the UF resin for improving the properties of medium density fiberboard (MDF). For this purpose, expanded graphite EG was synthesized from graphite using the Tsai et al (2011) method. Then, as-synthesized EG was intercalated with manganese dioxide by Schwarz et al (1995) method and converted to MnO2-EG. Both additives were individually added to the urea formaldehyde resin in three doses of 1, 2 and 3% (based on the dry weigth of UF resin) to make the MDF panels with 750 kg/m3 nominal density. During the pressing time, the tT0°c parameter (time to reach temperature100٥C) of the middle layer of the board under the influence of the additive was determined by a chromium-nickel-based thermocouple. The treatment of MnO2-EG3 (amount of 3% modified expanded graphite) showed the highest effect in reducing tT100°C of the middle layer of the board by 22%. In addition, the elastic modulus increased by 68% as a result of this treatment. G and EG additives showed a higher degree of internal bonding compared to MnO2-EG additive. In this regard, EG2 and EG3 treatments showed 42% increase in internal bonding and G2 treatment showed 40% increase in internal bonding. The effect of EG2 treatment in improving TS24 was greater than other treatments, so that it caused a 19% decrease compared to the control. [ABSTRACT FROM AUTHOR]

Composite wood materials, also known as engineered wood products, are fabricated from wood veneer, particles, strands, flakes, or fibers that are bonded together with synthetic or renewable, biobased adhesive systems and designed to meet a wide range of structural and non-structural applications [[1], [3]]. However, one of the major drawbacks of wood and wood-based composites is their high flammability [[30]], which has restricted their use as construction and building materials. Handbook of Wood Chemistry and Wood Composites; CRC Press: Boca Raton, FL, USA. [Extracted from the article]

Aircraft wing design using Multidisciplinary Design Optimization (MDO) techniques is a complex task that involves different disciplines, mainly aerodynamic and structure. This study develops and explores a coupled aero-structural multidisciplinary model that optimizes the performance of CRJ-700 aircraft, taking into account its path-dependent behavior. Two approaches, namely distributed and monolithic architectures, are available to achieve this aim. The decomposition strategies employed in these architectures differ and can significantly impact the design process. Therefore, comparing these methods can assist designers in understanding the design cost and accuracy of the results obtained. Eventually, optimizing the aircraft problem involved leveraging two methods: Multidisciplinary feasible (MDF) and Collaborative optimization (CO). Finally, the results obtained by two approaches; CO gives a high range value; MDF will be converged after 6013 times of the call function; but the number of call functions in the system-level of CO is around 4000 and the average of it for aerodynamic and structure optimizers are around 500 and 20, respectively. The range of the optimum wing of MDF approach raise about 41% and for CO approach raise about 66% compared to the baseline wing ranges. [ABSTRACT FROM AUTHOR]

Upright bipedal posture is the physiological human posture; however, it is not the only possible form of human standing; indeed, an inverted position, a handstand, is required during gymnastics or other sports. Thus, this study aimed to understand the differences between the two standing strategies from a postural and neuromuscular perspective. Thirteen gymnasts with at least three years of sports experience underwent a baropodometric assessment and a surface electromyography (sEMG) examination in a standard upright bipodalic stance and during a handstand. The sEMG examination was performed on the gastrocnemius during an upright stance and on the flexor carpi radialis during the handstand. Limb weight distribution presented differences between the two vertical stances (p < 0.01). During the handstand, the weight ratio was prevalently observed on the palm of the hand for both hands with a significant difference between the front and rear aspect of the hand compared to the standing tasks (p < 0.01). Normalized sEMG amplitude showed significant differences during bipedal standing and hand standing; however, over a 5 s period, the normalized median frequency (MDF) value was similar for the two tasks. Both standing tasks presented similar postural weight managing patterns when analysed on the frontal plane, but they were different on the sagittal plane. In addition, the neuromuscular patterns during a 5 s window differ in amplitude but not for the frequency domain. [ABSTRACT FROM AUTHOR]

The structural properties and whiteness of the substrate surface markedly effect printing quality and are closely related to the primer coating processes. Herein, four different roller coating schemes were applied on MDF surfaces to change their structural properties and color, and the whiteness, gloss, and roughness properties of the substrate surfaces were characterized for UV inkjet printing. Data analysis was conducted to explore the effects of these variables on the color reproduction, relative contrast, and printing gloss of the MDF substrates. The results showed that, according to CMYK, L*a*b* values and spectral reflectance data, the finishing of the MDF substrate with a 40 g/m2 layer of transparent primer combined with three layers of white primer at 20 g/m2 per roll coating layer had the best color reproduction effect for UV inkjet printing. Regarding the effects of relative contrast, the correlation with whiteness and glossiness was significant, while the correlation with glossiness was minor. The inkjet printing gloss value was positively correlated with substrate primer surface whiteness, while it was negatively correlated with roughness. When the surface whiteness of the substrate was relatively high, the roughness was lower and the printing effects were glossier. We sought to optimize the printing effects of all aspects of the MDF substrate by primer coating. The results of this work provide a feasible application method to improve printing quality and enhance the added value of low-quality boards, as well as to further expand the application of UV inkjet printing in the wood decoration market. [ABSTRACT FROM AUTHOR]

Traditional wood-based composites are bonded with synthetic formaldehyde-based adhesives [[1]]. 10.1155/2019/5256897 29 Antov P., Savov V., Neykov N. Reduction of Formaldehyde Emission from Engineered Wood Panels by Formaldehyde Scavengers - A Review. Another alternative to the use of synthetic formaldehyde-based adhesives is to manufacture binderless wood composites [[48]], since wood is a natural polymer material which is rich in lignocellulosic compounds such as cellulose, hemicellulose, and lignin. The properties of co-extruded wood/polyethylene composites (Co-WPCs) were improved by filling the shell and wood fiber layers with low-cost nano-silica (nSiO SB 2 sb ) and micro-silica (mSiO SB 2 sb ) [[34]]. [Extracted from the article]

Milling with use of CNC machines is a well-established method and much research was concluded on this topic. However, when it comes to wood and wood composites, the material non-homogeneity brings a lot of variability into cutting conditions. As a part of research into potential signals for nesting milling, material vibrations at clamping points were examined in this study. The main goal was to conclude if cutting parameters have a statistically significant effect on measurement. The place of measurement was analyzed so it was accessible to the machine operator. Medium density fiberboard and particleboard specimens were cut through by razor and spiral mill, with spindle rotating 10,000 and 20,000 min−1 and feed rates 2, 6, 10 m·min−1. Vibrations were measured at vacuum grippers, and were then processed by fast Fourier transform. Then, frequency spectrum maxima were compared, as well as amplitude sizes. Main frequencies were of roughly 166 Hz and multiples, suggesting their origin in tool rotation. When maxima were compared, tool use, spindle rotation, and feed rate seemed to affect the result. Frequency spectrum amplitudes were subjected to analysis of variance, significant effect was found on spindle speed, tool, and specimen material. No significant effect was found with differing feed rates. [ABSTRACT FROM AUTHOR]