Volume 21 Issue 4

This study was conducted to determine the effects of CO₂ laser scanning speed, laser processing power, and fiber direction on color change and surface roughness in Scots pine (Pinus sylvestris L.) and Eastern beech (Fagus orientalis Lipsky) wood. To this end, laser processing was performed at four scanning speeds (200, 300, 400, and 500 mm/s) and five power levels (12%, 13%, 14%, 15%, and 16%) in both parallel and perpendicular directions to the grain. The surface roughness and total color changes observed in the samples were determined in accordance with TS EN ISO 21920-2 and ASTM D2244-25 standards. As a result, while Scots pine samples exhibited higher roughness values than Eastern beech, the total color change was higher in Eastern beech samples. A low scanning speed and high laser power increased both roughness and color change. Processing parallel to the grain increased roughness, while processing perpendicular to the grain resulted in a higher color change.

Structural particleboard (SPB) is a promising structural wood-based panel that can be manufactured using existing particleboard production facilities. Although product performance requirements for SPB have been only partially established, developed SPB panels have demonstrated basic product-level properties such as bending performance, internal bond strength, moisture resistance, and formaldehyde emission. However, experimental verification of structural performance is required for practical structural applications. In this study, newly developed SPB was evaluated for product performance and structural performance, including compressive strength, structural bending performance, and in-plane shear strength, and the results were compared with those of conventional particleboard (PB) and oriented strand board (OSB). To assess reliability as a structural material, coefficients of variation and 5^th percentile were examined in addition to mean values. SPB satisfied all product performance requirements and showed superior compressive performance compared with OSB and conventional PB in terms of both mean and 5^th percentile. In bending, SPB exhibited structural performance comparable to that of OSB in the major axis and showed competitive performance based on the 5^th percentile. In-plane shear performance was also stable in terms of mean value, variability, and 5^th percentile. These findings demonstrate that SPB has strong potential for use as a structural wood-based panel.

As a major consumer of soybean, the growth in China’s annual soybean production is crucial to its national food security. Both maize and soybean are upland crops with overlapping growth periods, leading to trade-offs in production when either crop is cultivated as a sole crop. However, the soybean-maize strip intercropping system enables the production of an additional soybean harvest with only a slight reduction or no loss in maize yield, thereby making a highly significant contribution to the expansion of total grain output. This study explored the effects of maize varietal traits and maize density on the production indicators of the two crops under this intercropping model by designing different maize varieties and maize planting densities. The results showed that maize lodging extent had an extremely significant negative correlation with maize yield and gross income. Maize plant height had a significant negative correlation with maize 100-grain weight, soybean SPAD values, and soybean grains per plant. Within a certain range, as maize density increased, maize yield first increased and then decreased, while soybean yield showed a continuous downward trend. Based on this regularity, a quadratic function mathematical model was constructed, with maize planting density as the independent variable and production benefit per unit area as the dependent variable. This model can be used to determine the optimal maize planting density for soybean-maize relay strip intercropping. This study identifies suitable maize varieties and optimal planting density, thereby providing references for local production practices.

Silver–selenium nanoparticles (Ag–Se NPs) were successfully prepared using Punica granatum peel extract via a green, eco-friendly, and cost-effective approach. The formation of nanoparticles was confirmed by a characteristic UV–Vis absorbance peak at 436 nm, while FTIR analysis indicated the involvement of functional groups in reduction and stabilization. TEM analysis showed predominantly spherical nanoparticles with an average size of 44.9 ± 19 nm. The synthesized Ag–Se NPs exhibited effective antibacterial activity against Staphylococcus aureus, Escherichia coli, and Bacillus subtilis, with inhibition zones of 17.8, 20.3, and 16.2 mm, respectively. The MIC values ranged from 62.5 to 500 µg/mL, confirming concentration-dependent antimicrobial activity. The nanoparticles showed significant antibiofilm activity, reaching 62.3% inhibition against E. coli at higher concentrations. Cytotoxicity evaluation demonstrated selective activity, with IC₅₀ values of 209 µg/mL for Vero normal cells and 115 µg/mL for MCF-7 cancer cells. Furthermore, antioxidant activity assessed by DPPH and ABTS assays showed IC₅₀ values of 458 and 312 µg/mL, respectively. Overall, the results indicate that green-synthesized Ag–Se NPs possess multifunctional biological activities, making them promising candidates for antimicrobial, anticancer, and antioxidant applications.

Lactic acid (LA) is a growing demand platform chemical for food, pharmaceutical, and bioplastic applications. Lignocellulose offers an alternative to edible sugars as a substrate. However, its microbial conversion of mixed hexose/pentose sugars remains challenging. In this study, two new lactic acid bacteria with distinct sugar utilization profiles were isolated and evaluated for their LA production capability using a series of substrates. Enterococcus casseliflavus CW3-1 exhibited a partially homofermentative behavior and was capable of assimilating both hexose and pentose sugars. In contrast, Paucilactobacillus vaccinostercus MQ2 showed a heterofermentative manner and was a typical pentose-preferring bacterium, which did not metabolize glucose. In the simultaneous saccharification and fermentation (SSF) of alkali-pretreated corn stover and sugarcane bagasse with a commercial cellulase, co-cultivation of the two strains significantly outperformed the mono-cultures and the LA production from co-culture was slightly higher than the sum of the production from the two monocultures. Fermentation results from two types of biomasses showed that the maximum LA yield reached 0.78±0.03 g/g substrate; however, increasing the substrate concentration led to a decrease in yield. These results demonstrate the superiority of using microbial consortia for sustainable LA biorefining from lignocellulosic biomass.

This preliminary, limited case study compared reclaimed Juniperus excelsa (Greek juniper) wood—removed after approximately 42 years of service in a rural structure—with freshly cut samples from the same geographic region. Compressive strength parallel and perpendicular to the grain, full-section four-point bending, a study-specific visual defect index, and qualitative scanning electron microscopy (SEM) observations were used. Test results showed that parallel compression and bending strengths were of similar magnitude in the two groups, whereas perpendicular compression showed a larger difference. These differences were not interpreted as a loss or preservation of properties, as the initial properties and detailed service history of the reclaimed specimens are unknown. In the new group, a distinct trend of decreasing bending strength with increasing visible defect scores was evident, whereas the narrow score range in the reclaimed group did not support a similar relationship. Some reclaimed specimens fractured abruptly near the peak load. Local microcrack-like discontinuities observed in selected SEM fields were qualitatively consistent with this behavior but did not establish causality. Due to the small sample sizes, the results provide preliminary engineering trends rather than design values.

Urban parks are increasingly expected to support rest, relaxation, and restorative perception under accelerating urbanization and everyday stress. However, studies on park seating still lack a systematic pathway for translating user demands into design elements and selecting design alternatives. Taking restorative-oriented wooden seating in urban parks as the object, this study developed a GT–Kano–AHP–QFD–TOPSIS hybrid model. Semi-structured interviews with 30 park users were analyzed using grounded theory. Kano classification was then conducted using 91 valid questionnaires. Twelve experts applied AHP to weight 13 user demand items, which were translated into design elements through QFD. Finally, 17 evaluators rated three design alternatives on a seven-point scale, and TOPSIS was used for ranking. The results showed that seating comfort, ergonomic dimensional optimization, and aesthetic form had the highest weights, at 0.1614, 0.1404, and 0.1321, respectively. Ergonomic dimensions, backrest design, lumbar support, multi-user adaptability, and aesthetic form were identified as priority design elements. Alternative 3 achieved the highest relative closeness coefficient (0.8007), indicating the best overall performance. This study provides a traceable user-oriented decision pathway for wooden park seating design, while its findings reflect perceived preferences rather than clinically or physiologically verified outcomes.

Amongst industrial lignins, such as alkaline and kraft lignins, lignin from hemicellulose pre-treatment liquor is gaining considerable interest because of its various properties. To explore application potential, a lignin sample that was selectively adsorbed by XAD-16N resin from mild alkaline extracts of sugarcane bagasse waste was identified by structural analysis. Trace amounts of hemicellulose were found in the adsorbates that exhibited lignin carbohydrate complexes (LCCs) structure. Prominent NMR signals indicated β-O-4ʹ, β-5ʹ, β-βʹ, and β-1ʹ structures in the side chain, and aromatic signals corresponded to major bagasse lignin units: p-coumarate and ferulate. The quantity of benzyl ether (BE) was 3.33 per 100 Ar-units, which was considerably higher than that of hydrolysate obtained from hydrothermal pretreatments. The content of various hydroxyl groups of mild alkaline lignin obtained by resin adsorption was higher than that of lignin isolated by other methods. Moreover, the adsorbed lignin was relatively pure, and its thermal stability was superior to that of the centrifuged lignin. These results revealed new characteristics of lignin and LCC structures obtained via mild alkaline pretreatment and resin adsorption.

This study investigated the photochemical transformation of amber oil under UV irradiation and its impact on biological activities. Gas chromatography–mass spectrometry analysis showed that untreated amber oil was rich in long-chain hydrocarbons and fatty acids, predominantly cis-vaccenic acid (36.53%), whereas UV irradiation produced oxygenated compounds, mainly 2-(2-hydroxypropoxy)-1-propanol (13.02%), 1,1′-oxybis-2-propanol (6.93%), and diethyl phthalate (6.73%). UV-treated oil exhibited enhanced antimicrobial activity, particularly against Bacillus subtilis (22 ± 1.0 mm; MIC 15.62 µg/mL) and Candida albicans (24 ± 0.5 mm; MIC 15.62 µg/mL). Strong antibiofilm activity was recorded, exceeding 90% inhibition at 75% MBC against tested bacteria, including Staphylococcus aureus and Escherichia coli. Anti-inflammatory evaluation showed effective inhibition of protein denaturation (IC₅₀ = 2.60 ± 0.11 µg/g). Wound healing assays showed a high closure (90.9%) for UV-treated oil, compared to untreated oil (61.1%). Molecular docking revealed that cis-vaccenic acid exhibited stronger binding affinity toward the target proteins of Aspergillus terreus (4KWD) and B. subtilis (3OIF) than 2-(2-hydroxypropoxy)-1-propanol, with docking scores of −6.64 and −7.12 kcal/mol, respectively. These findings demonstrate that UV-induced photochemical modification is an effective approach to enhance the biological properties of amber oil, providing a basis for its further investigation in natural bioactive product applications.

The effects of chitosan, poly-DADMAC, and cationic polyacrylamide (cPAM) were evaluated relative to the optical and mechanical properties of paper from chemical-mechanical pulp (CMP) from Mazandaran Pulp and Paper Mill. Additives were applied at different concentrations: chitosan (0%, 1%, and 2%), poly(diallyldimethylammonium chloride) (poly-DADMAC): 0%, 0.3%, 0.5%, and 0.7%), and cPAM (0%, 0.25%, 0.5%, and 0.75%). Papers with a basis weight of 60 g/m² were prepared, and brightness, opacity, a* factor, tensile strength, breaking length, tear strength, and burst strength were evaluated. Factorial analysis of variance showed that the effects of the three additives varied depending on the property evaluated. Chitosan positively affected brightness, breaking length, and tear strength; PAM showed a particularly strong effect on breaking length and tensile strength; and poly-DADMAC contributed to improvements in brightness, tensile strength, and the a* factor. Scanning electron microscopy showed a relatively denser and more interconnected fiber network in treated papers, with fewer visibly open void spaces and greater apparent fiber contact. These morphological changes may be associated with improved inter-fiber interactions and the observed changes in paper properties. Among the tested formulations, the combination of 2% chitosan, 0.25% cPAM, and 0.7% poly-DADMAC provided favorable overall performance.