Volume 20 Issue 3

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.

Enzymatic refining offers a sustainable alternative to mechanical refining for enhancing the quality of recycled paper fibers. This review examines (a) the benefits and limitations of enzymatic refining and (b) the most commonly used enzymes and their effectiveness. Studies from 2008 to 2023 were systematically analyzed using PRISMA screening to assess enzyme types, energy savings, and paper property improvements. Findings indicate that enzymatic refining reduces energy consumption by up to 20% while improving fiber bonding and drainage. Cellulases and hemicellulases are the most effective enzymes, enhancing mechanical strength and reducing water use. However, enzymatic refining alone is often insufficient, requiring additional mechanical refining for optimal results. Industrial adoption of enzymatic refining remains limited due to challenges in process integration and reaction optimization. This study highlights the role of this kind of refining in advancing circular economy goals and emphasizes future research needs, including enzyme formulation optimization and the development of scalable, one-step refining solutions.

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.

The free drying shrinkage of wood is critical for dimensional stability and industrial applications. This study reviews the influencing factors (drying parameters, environmental conditions, and anatomical structures) and summarizes evaluation indexes and measurement methods. However, current research exhibits significant limitations. Systematic comparisons of free drying shrinkage between softwoods and hardwoods have been lacking, and the mechanism by which internal moisture variations affect shrinkage have remained unclear. Furthermore, existing techniques have failed to simultaneously measure moisture content changes and shrinkage with high accuracy. To address these gaps, future studies should: 1) investigate species-specific free drying shrinkage conditions; 2) elucidate moisture-induced shrinkage mechanisms from macro- and micro-scale perspectives; and 3) develop high-resolution methods for synchronous measurements. Further industrial applications of these findings could optimize wood drying processes and advance wood science and processing technologies.

This article reviews published literature related to the coating of wood surfaces for external applications. Research has shown that a wide range of procedural steps and components in coating formulations can contribute to increasing the effective service life of the coating as well as to maintaining the quality of the coated wood surfaces. Published findings support the idea that the commonly observed service life of painted wood surfaces exposed to outdoor weather can be significantly increased by dedicated application of such measures as optimized sanding, the use of an effective primary coat, the type of resin in the finish coat, increasing the number of layers of the finish coat, and a wide range of issues related to formulation of the finish coat. Even if a majority of contractors and homebuyers continue to prefer such options as vinyl or aluminum siding, the market opportunities remain very large for clients who prefer to rely on coatings and wood products for exterior surfaces of buildings and other exterior wood items.

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.

Corrugated board boxes are used for the majority of parcel shipments. These boxes, particularly in e-commerce shipments, often suffer damages such as crushing and puncturing. Puncture-related damage can lead to product damage, customer dissatisfaction, and costly returns. While holes in boxes due to rough handling in the distribution chain are common, there is no standardized method for designing corrugated board properties to resist puncturing, particularly by selecting appropriate paper materials without extensive laboratory testing. This study demonstrates how commonly measured properties can be leveraged to optimize corrugated board paper combinations, tailoring them to minimize the occurrence of holes, as well as general damage, during distribution.