Research Articles

This study proposes an innovative product design to enhance the safety of indoor furniture. Currently, furniture presents safety concerns due to various factors such as improper placement, excessive loads, and environmental influences. The most prominent of these safety issues is furniture tip-over. Therefore, product designs aimed at preventing tip-over have been developed to ensure safety in indoor environments and avert potential accidents. In the initial phase of the study, the factors contributing to tip-over in a standard cabinet were investigated: the height of force application, leg diameter, leg length, leg’s position on the bottom panel, and the furniture’s load status. In the second phase, designs to prevent tip-over were developed. Following prototype production stages, the developed product was mounted on the cabinet, and experiments incorporating product variables and other variations were conducted. The results indicate that the effectiveness of the developed tip-over prevention product varies depending on usage, with its impact on preventing tip-over ranging between 17.5% and 54.3%. These findings suggest that the designed product can significantly enhance indoor safety and offers a potential alternative solution for preventing furniture tip-over.

Methods for surface moisturization and control of internal moisture movement have been developed to minimize moisture gradients and reduce drying defects, such as cracks, in large cross-sectional timbers used for restoring palaces, temples, and cultural heritage buildings. Cross-sectional sealing and steaming pre-treatments were applied before kiln drying to regulate the internal moisture transfer. Real-time weight changes were monitored using a load cell to track the average moisture content, and hygrometers were used to estimate the moisture content at various positions within the wood. The experimental results demonstrated that the cross-sectional coating with lateral moisturization effectively reduced drying defects, thereby contributing to the preservation of wooden cultural heritage sites and enhancing the sustainability of timber resources. The total drying duration was 835.4 h (approximately 35 d), confirming that surface moisturization is critical in minimizing defects during drying.

The machining processing of wood-plastic composites (WPCs) has some technological gaps in the field of surface damage mechanism and surface quality monitoring. In this study, orthogonal cutting tests were used to investigate the mechanisms of surface damage and the degree of chip (the material cutting off by cutting tool) curling of WPCs with various tool rake angles (from 5 ° to 40 °) and cutting depths (from 0.1 to 1 mm). Based on observations of the processed surface micromorphology, a surface damage model is proposed to describe the temperature-dependent reduction in adhesion force between polyethylene and wood flour. Chip curling was quantified by the point curvature in the side view. The curvature data for each chip point were negatively correlated with the depth of cut, but the relationship with the tool rake angle was less pronounced. The surface damage mechanism of WPCs during machining was revealed, providing a theoretical basis for improving surface quality through material formulation. The analysis of chip curvature offers theoretical support for the dynamic observation of chip morphology and elucidates the relationship between chip morphology, cutting depth, and tool rake angle. These findings can serve as a foundation for monitoring cutting precision in practical production.

Over the past decades, consistent efforts have been dedicated to addressing the challenge of low performance of protein-based wood adhesives. This study explored the potential of polyethyleneimine (PEI) as a crosslinker for improving the bonding strength of canola protein isolate (CPI) and canola meal (CM) bio-adhesive. Simultaneously, the effect of the pH value of the slurry was investigated. Three-layer particleboards were manufactured using the canola-based adhesives and subjected to testing for their internal bonding strength (IB), bending strength (BS), and modulus of elasticity (E-modulus). Results showed that, despite the low PEI ratio utilized, notable enhancements in the mechanical properties of the boards were observed. The IB values increased by 17% and 15% for CPI and CM-based adhesive formulations, respectively; while the BS exhibited rose by 13% and 9%, respectively. It was observed that an increase in pH contributed to enhanced bonding properties of the bio-based adhesive. By enhancing the denaturation of the protein and increasing the free reaction group in the protein chain, this improves the crosslinking mechanism of PEI, leading to improved mechanical properties.

This study presents an eco-friendly strategy to valorize Polygonatum cryptonym Hua flavonoids (PC) from the residues of polysaccharide extraction by synthesizing silver nanoparticles (PC-AgNPs) with enhanced bioactivity. Optimized synthesis (pH 7.5, 10 mM Ag⁺, 55 °C, 30 min) yielded monodisperse, spherical PC-AgNPs (avg. 16.2 nm) with face-centered cubic crystal structure. Nanoparticles showed remarkable scavenging ability for DPPH free radical (SC₅₀ = 2.61 µg/mL) and ABTS free radical (SC₅₀ = 1.65 µg/mL) compared to the native PC samples. The PC-AgNPs were incorporated into polylactic acid (PLA) films (1% w/w), achieving superior mechanical performance (tensile strength: 54.6 MPa; elongation at break: 6.0%) while demonstrating broad-spectrum antimicrobial activity against E. coli, S. aureus, and A. niger. Mechanistic studies revealed that the nanocomposite film disrupted bacterial membrane integrity in E. coli. Applied to litchi preservation at -18°C, the 1%NPs/PLA coating effectively maintained mitochondrial enzyme activities (Succinate dehydrogenase, Cytochrome c oxidase, H⁺-ATPase, Ca²⁺-ATPase) at more than 80% of fresh fruit levels for a certain storage life, significantly delaying senescence compared to controls. These findings establish PC-AgNPs/PLA as a dual-functional active packaging material that synergistically combines antioxidant reinforcement, antimicrobial protection, and physiological regulation for postharvest fruit preservation.

The medicinal and aromatic plant species naturally found in Türkiye are particularly noteworthy. Among them, Phlomis L., a genus within the Lamiaceae family, stands out for its numerous species. This study, conducted in Uludağ (Bursa), aimed to analyze the morphological traits, volatile components, ratios, and molecules present in the leaves and flowers of Phlomis russeliana (Sims) Bentham and P. armeniaca Willd. Samples were collected during their flowering period using a random sampling method. Their morphological characteristics were analyzed using Microsoft Excel and IBM SPSS software, while the volatile components of the leaf and flower samples were identified through the HS-SPME/GC-MS method. The morphological characteristics of Phlomis russeliana and P. armeniaca were examined in detail. The leaf widths and lengths, petiole lengths, number of flowers, petal lengths, sepal lengths were measured. 32 different components were identified in P. russeliana and 43 different components in P. armeniaca, summing up to 56 different components. The main components identified were caryophyllene (31.6%; 26.4%), (E)-β-farnesene (19.6%; 25.2%), and germacrene-D (25.7%; 16.5%), respectively. Such studies are crucial for enhancing the protection and sustainable management of non-wood forest products, which significantly contribute to our country’s economy and play a pivotal role, especially in rural economies.

This paper considers the possibility of using Siberian fir (Abies sibirica) wood damaged by Polygraphus proximus Blandford after various periods of its death (up to 19 years) as raw material to produce fiberboard. Damaged wood was mechanically processed into chips of various dimensions as per GOST 15815(1983). The produced chips were used to prepare wood fiber pulp using thermomechanical methods and two stages of grinding with approximately the same conditions as those used to produce wet fiberboard. Fiber refining was performed using fibrillating refiner discs with all other conditions being equal. The paper considered the changes in quality indicators and fractional composition of fibers during the preparation of wood fiber pulp after different periods of wood death, as well as physical and mechanical properties of produced boards. The obtained research results may indicate the possibility of effectively using damaged Siberian fir wood after different periods of its death as raw material to produce fiberboards, while providing physical and mechanical properties of products (density 960 to 1070 kg/m³, static bending strength 36 to 44 MPa, internal bonding 0.51 to 0.7 MPa, modulus of elasticity 3880 to 4750 MPa, deflection 2.7 to 3.6 mm) that comply with GOST 4598-2018 (EN 622-2), while not requiring binding resins.

This study determines the note for a sundatang, a traditional musical instrument in Borneo. The sundatang originated from two different ethnics so the strings were tuned differently as well as frets and it clearly produces more than one note. The sound was recorded using a microphone which was connected to a PicoScope and analyzed using Fast Fourier Transform (FFT). The string 1 and 2 for sundatang A are tuned to E4(330Hz) and E3(161Hz) respectively, and sundatang B are tuned to C4#(277Hz) and C3#(138.59Hz) respectively. Open string 1 and the fret from sundatang A was tuned to E4(330), G4#(410), A4#(465), C5#(546), D5(569), and F5(692) where E4-G4#:2Tone, G4#-A4#:1Tone, A4#-C5#:2Tone, C5#-D5:1Tone, D5-F5:2Tone, simplified become 2TT2TT2T. Open string 1 and the fret from sundatang B it was tuned to C4#(277), E4(329), F4(340), F4#(361), G4(389), G4#(425) where C4#-E4:1.5Tone, E4-F4:1Semitone, F4-F4#:1Semitone, F4#-G4:1Semitone, G4-G4#:1Semitone simplified become 1.5TSSSS. The note interval for string 1 and 2 for sundatang A and B can be formulated as y = 67.6x + 332.8 and y = 30.2x + 272.1, respectively. The time frequency analysis of the open strings 1 and 2 displayed a dense distribution of partials while fret 1 to 5 showed a distinct distribution which decrease with fret number.

Additive Manufacturing (AM) is a digital manufacturing method that creates structures by adding material layer by layer. This approach offers simplicity, speed, and efficiency. Additive manufacturing methods can process wood-plastic composites, but they are often limited by poor surface quality, low interfacial bonding, and the requirement for complex post-processing. In this study, walnut shell and photosensitive resin were used to fabricate wood-plastic composite specimens with varying walnut shell powder contents using DLP technology. The properties analyzed included dimensional shrinkage, mechanical strength, double bond conversion rate, and microstructure. The results indicated that as the walnut shell content increased, the dimensional shrinkage of the formed parts initially decreased and then increased, reaching the minimum value of 0.631% at 12% walnut shell powder content. SEM imaging revealed that resin infiltrates the particle pores, forming a network structure that enhances mechanical performance. Tensile and flexural strengths also reached their peak values at 8% content, measuring 17.7 and 45.4 MPa, respectively, while impact strength decreased with increasing walnut shell content.

Effects of annual hemp (Cannabis sativa L.) material on the mechanical and physical properties of particleboard was investigated. For this purpose, various levels of hemp shives 10%, 20%, and 30% were added to the middle layer of the chip blank. Urea formaldehyde (UF) resin was used at a 7% level in the middle layer and 12% in the top layer, in proportion to the dry chip weight, as an adhesive. Chip blanks were pressed in a hydraulic press at 195±5 °C temperature, 30 kg/cm² pressure, and 300 s.  Test samples of P1 type with dimensions of 550 × 550 × 19 mm and a density of 580 kg/m³ were produced. It was understood from the test results that hemp sawdust had a positive effect on the mechanical properties of particleboard. Accordingly, a 16.7% increase in tensile strength, 18.4% in bending strength, 23.6% in elasticity modulus, 17.2% in surface strength, and 7.5% in screw holding force were detected. Physical properties showed a 3.8% increase in thickness and a 15.5% increase in water absorption values. Free formaldehyde values decreased by 24.6%. As a result of the research, it was determined that hemp sawdust could be an alternative to wood raw material in P1 type particle board production.