Volume 20 Issue 2

This study evaluated the outdoor performance of wood-plastic composites (WPCs) coated with epoxy-based coatings containing graphene nanoplatelets (GNPs) after 336 h of artificial weathering. Results indicated that color change is inevitable. The GNPs covered the surface of the WPCs and restrained the UV degradation. The lowest color changes were observed in the 0.5% GNPs coating. Contrastingly, crack formations were noted on the coating surface without GNPs. Scanning electron microscopy analysis clearly revealed the splitting of the coating due to UV exposure. As the GNPs ratios increased, the crack formation decreased. Similarly, the macroscopic investigation showed that the surface roughness of the coatings decreased with increasing GNPs. Color stabilization also improved with the increased GNPs. Meanwhile, color changes occurred more rapidly in WPCs coated with pure epoxy. Epoxy-based coatings containing GNPs effectively stabilized the surface color. Additionally, GNPs restricted mechanical losses, with a reduction of only 3.68% for the epoxy coating containing 1% GNPs, compared to a 19% loss in pure epoxy-coated WPCs. In conclusion, coatings containing GNPs considerably enhanced the weathering performance of WPCs.

This study designed a corn kernel drying device and optimized the structure of key components. FLUENT software was used for numerical simulation of wet heat coupling. The differences in physical fields were compared within the drying section before and after optimization. The optimized drying section exhibited improved drying uniformity, drying efficiency, and drying quality. The optimized drying section took 180 seconds for the temperature at the center point to reach the expected value, while the mixed flow drying section took 240 seconds. The moisture content of the optimized drying section decreased to 3.79% at this point, while that of the mixed flow drying section was 2.89%. The results indicated that the drying uniformity and efficiency of the optimized drying structure were higher than those of the mixed flow drying structure. This research provides important data for the design of corn drying equipment.

This paper aims to optimize the product design of nail tables and chairs and enhance user satisfaction. It proposes a comprehensive and visualized design process for developing dual-category user products that balance the needs of two distinct user groups: nail technicians and customers. Leveraging the Kano model, DEMATEL method, and TRIZ theory, the process includes four key steps: gathering dual-category user requirements, categorizing requirement attributes, analyzing the interrelationships between requirements, and resolving design conflicts. Using the design of nail tables and chairs as a case study, the paper empirically demonstrates how to balance the operational efficiency of nail technicians with the customer experience. This approach not only optimizes the design of nail tables and chairs but also offers valuable insights for requirement prioritization and iterative development of other dual-category user products.

This study explored the applicability of oleander (Nerium oleander L.) extract and hydrosol as protective agents for wood materials. The research examined their effects on the physical properties of red pine (Pinus brutia), Oriental beech (Fagus orientalis), and walnut (Juglans regia) following an impregnation process. Wood samples were treated with oleander-based solutions using the dipping method and then subjected to water immersion for various durations to assess retention, specific gravity, shrinkage, swelling, and water uptake. The results indicated that while oleander extract had no significant impact on wood retention, hydrosol enhanced water resistance and dimensional stability. However, the use of mordant increased shrinkage percentages, particularly in Oriental beech and walnut at prolonged exposure times. These findings suggest that hydrosol-based treatments can contribute to improving wood durability, offering an environmentally friendly alternative for wood preservation.

The escalating global demand for energy, coupled with heightened environmental concerns, has rendered the identification of sustainable and environmentally friendly alternative energy sources imperative. Ethanol derived from cellulosic fibers is garnering significant interest as a clean and renewable energy source. Among the various production methods, consolidated bioprocessing (CBP) stands out due to its distinct advantages. Clostridium thermocellum is considered an exemplary candidate strain for the CBP production of cellulosic ethanol; however, the low yield of ethanol remains a critical limiting factor. In the preceding study, it was demonstrated that neodymium ions could enhance the ethanol production of C. thermocellum. In this study, the whole genome sequences of the original strain C. thermocellum ATCC 27405 (C0) and the strain with added neodymium ions (Nd³⁺) (C1) were sequenced and analyzed. The findings indicated that the increased expression of pyruvate-ferric redox protease (PFO) resulted from mutations in its promoter region. Furthermore, an analysis of the sequencing data, along with the results from single knockout experiments, revealed that mutations in the genes encoding methyl-accepting chemotaxis proteins (MCP) and type 3a cellulose-binding domain protein (Type) genes were correlated with enhanced ethanol production. This study serves as a reference for the targeted modification of C. thermocellum to optimize ethanol production.

There has been a growing interest in using natural alternatives to synthetic additives in animal feed. This study aimed to examine the physicochemical properties of signal grass (Brachiaria decumbens) and its cost-benefit application in broiler production. The characterization was performed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric/derivative thermogravimetry (TG/DTG), and scanning electron microscopy (SEM). A feeding trial involving 216 Sasso broiler chicks was conducted to assess the economic value of including B. decumbens grass meal in their diets. The chicks were divided into six groups, with Treatments 1 and 2 serving as controls (without antibiotics and with oxytetracycline, respectively). Treatments 3 to 6 received diets supplemented with 1.25, 2.50, 3.75, and 5.00 g/kg of B. decumbens grass meal without antibiotics. Body weight and feed intake were monitored over eight weeks to determine growth performance and feed conversion ratio. Broilers in Treatment 6, which received 5.00 g/kg of the grass meal, showed significantly improved growth (p < 0.05). A cost-benefit analysis revealed that T6 was the most profitable, suggesting B. decumbens‘ potential as an effective feed additive for broilers.

This study investigated the effect of using infused black tea leaf wastes (TLW) on the three-layer particleboard’s mechanical, physical, and formaldehyde emission properties. Particleboards were composed of 70% core layer and 30% surface layers. The TLW was used in the core layer, surface layers, or as whole material. Mechanical and physical properties, including internal bond strength, modulus of rupter, modulus of elasticity, water absorption, thickness swelling, and density of the samples, were determined according to EN 319 (1993), EN 310 (1993), EN 317 (1993), and EN 323 (1993) standards, respectively. The perforator method determined the formaldehyde content EN 120, (1999). Results showed that 100% TLW utilization in surface layers (Board Type: T/W/T), core layer (Board Type: W/T/W), or whole particleboard (Board Type: T) did not provide the standard internal bond (IB) requirement of 0.35 N/mm². W, 15%T+85%W, and 30%T+70% board groups fulfilled the IB strength TS EN 319, (1993). 15%T+85%W board group provided the best modulus of rupter values. The amount of formaldehyde emission in the groups with 15%T+85%W, 30%T +70%W met the E1  standard. Results showed that TLW could be an alternative raw material by mixing with wood particles in particleboard production.

Increasing concerns regarding plastic waste and its impact on the environment have prompted a global trend to replace plastic films with fiber-based packaging solutions. Though the heat-sealing of polyolefin films provides a simple approach for realizing flexible packaging, paper does not have the natural attributes required for such applications. Therefore, paper sealability must be achieved by other means such as coating or varnishing. This study accordingly investigated the basics of imparting heat-sealability to packaging paper using overprint varnish applied with a lab coater simulating flexographic printing. The sealing and grease resistance properties of the resulting paper were compared with those of commercially available polyethylene dispersion-coated paper and oriented polypropylene/polyethylene laminate. The results confirmed that sufficient capabilities were realized using the proposed method; though the varnished paper exhibited a lower seal strength than the reference plastic films, it exhibited adequate properties for package sealing regardless of applied temperature. These observations were subsequently discussed to inform recommendations for further investigation and development.

The heat and sound insulation properties of the heartwood and sapwood of willow (Salix alba L.) were investigated.  Based on the experimental results, it was determined that the density value of the heartwood of the willow tree was higher than that of sapwood, while the moisture value was lower in the sapwood. The thermal conductivity coefficient was 0.090 W/m.K in sapwood and 0.103 W/m.K in heartwood; thermal transmittance coefficient was 3.954 W/m².K in sapwood and 4.738 W/m².K in heartwood. The sound absorption coefficient was highest in sapwood at 1000 Hz frequency level with 0.37, while the highest in heartwood was 0.50 at 800 Hz frequency level. These results would be useful in willow wood structural applications.

The seung instrument is played in one key (minor key) because the fret spacing creates a diatonic scale. Due to the fact that the frets are not uniformly spaced on the fretboard, the fret spacing produces a diatonic scale (do-re-mi-fa, etc.) instead of a chromatic scale of a guitar, where all the flats and sharps are available. The partial frequency (Hz) versus harmonic number for string 1 and 2 are very linear. The gradients of the linear equations fit very well with the fundamental frequency of the open string 1 and 2 and fret 1 to fret 9. The sounds were digitally captured using a PicoScope oscilloscope and were subsequently examined utilizing PicoScope software, emphasizing Fast Fourier Transform (FFT). The Time Frequency Analysis (TFA) was obtained via Adobe Audition. The notes for open string 1 and 2 are A4 followed by B4, C5, D5, E5, F5, G5, A5, B5, C6, and D4 followed by E4, F4, G4, A4, B4, C5, D5, E5, F5 from the 9 frets respectively. The 10 notes up to the 9^th frets for string 1 and 2 are A4 to C5 and D4 to F5 respectively.