Research Articles

The convergence or divergence of results for pH, yellowness, and mechanical strength were considered for papers from three old books. Good convergence was found for pH measurement results from the three books. The lack of convergence in some pH measurements between the surface method and the extraction–pH meter method may result from differences in pH of individual pages of old books, inherently lower pH values obtained using the surface methods, as well as from lower pH values measured in extracts of old papers prepared under hot conditions using a pH meter. Yellowness testing revealed overall good level of convergence between visual assessment and instrumental measurement (Elrepho 2000 apparatus). Strength tests indicated convergence between the results of the number of double folds (NDF) and tensile-after-six folds (TSF) tests, while divergence was observed when these methods were compared with the number of page turns (NPT) test. High NPT values may result from the papers of the examined books retaining yet relatively significant resistance to tensile and tearing stresses. Further research is needed to explain the relatively small damage to book pages in the NPT test in contrast to alarming results of the NDF and TSF tests.

To accurately elucidate the microscopic degradation characteristics and deterioration mechanisms of wooden components in traditional northern Chinese dwellings, this study investigated wooden components retrieved from the Ming-Qing residential building at No. 9, East Gate Lane, Gulian Village, Qi County, Shanxi Province. Polarized light microscopy, fluorescence microscopy, and histochemical staining techniques were employed to qualitatively assess the degradation degrees of cellulose and lignin in six wood species: elm, poplar, willow, birch, Chinese larch, and Chinese pine. Internal and external deterioration drivers were analyzed, and corresponding conservation strategies were proposed. The results showed that all tested wooden components exhibit moderate to severe chemical degradation. The deterioration of wooden components is synergistically driven by interspecific differences in natural decay resistance, rainwater erosion, ultraviolet radiation, building structural damage, and microbial infestation. Elm components are mainly attacked by white-rot fungi, while the other wood species are predominantly affected by soft-rot fungi. Poplar and willow are more susceptible to insect damage. This study provides a scientific basis and technical support for the microscopic diagnosis, precise restoration, and preventive conservation of Ming-Qing wooden architecture in the Jinzhong region.

Resin-inlaid wood is a material integration approach in which liquid resin is poured into cracks or structural cavities of wood and cured to form a composite structure. In recent years, this technique has attracted increasing attention in furniture and interior design due to the distinctive visual and tactile effects created by the contrast between resin and wood, inspiring numerous handcrafted and design-oriented works. However, systematic studies on resin-inlaid wood remain limited. This study reviews the material selection and processing procedures involved in resin-inlaid wood craftsmanship and analyzes its aesthetic characteristics from the perspectives of visual presentation, tactile contrast, structural expression, and emotional values. Representative household products are further examined through case analyses. In addition, a questionnaire survey based on the product semantics approach was conducted to explore participants’ preferences toward resin-inlaid wood products, providing references for the design application and future development of resin-inlaid wood in household products.

Kombucha pellicles (Kombucha microbial culture) were evaluated as a source of bacterial cellulose to use in the production of laminated wood material. The goal was to improve the mechanical properties. The Kombucha pellicles were produced at room temperature over an eight-week fermentation period, after which bacterial cellulose sheets approximately 1 mm thick were obtained by drying. These sheets were used in the production of laminated wood material together with Scots pine (Pinus sylvestris L.), Oriental beech (Fagus orientalis L.), and Anatolian chestnut (Castanea sativa Mill.) wood species, utilizing urea formaldehyde, polyurethane, and polyvinyl acetate adhesives. To evaluate the mechanical properties, the following tests were applied: compressive strength parallel to the grain, adhesive strength, bending strength, and modulus of elasticity in bending. The findings revealed that although bacterial cellulose displayed a mechanically strong structure, overall mechanical performance did not reach the desired level due to insufficient adhesion between lamina layers. The results indicated that further research is needed to improve structural compatibility and adhesion mechanisms for the use of this material in advanced mechanical applications.

Scots pine wood (Pinus sylvestris) specimens were thermally modified using the rectification method and subsequently exposed to air-plasma under atmospheric pressure for 5 and 7 min. The water contact angle and CIELAB color parameters, including lightness (L*), red–green (a*), and yellow–blue (b*) coordinates, were measured. The results showed that plasma treatment decreased L*, particularly in thermally modified wood, while inducing a slight decrease in untreated wood. The b* value gradually increased in untreated samples, whereas thermally modified specimens exhibited pronounced increases in both a* and b*. Analysis of variance revealed that wood type, plasma exposure time, and their interaction had statistically significant effects on all three-color parameters. Plasma treatment markedly reduced the water contact angle in both solid pine and thermo-wood samples, demonstrating enhanced surface wettability. The strongest effect was observed in thermo wood exposed to plasma for 7 min, which exhibited the lowest contact angle and the highest level of hydrophilicity among all treatments. FTIR spectroscopy indicated a gradual reduction of hydroxyl groups and ester carbonyls in hemicellulose and an accumulation of polymerized lignin caused by thermal modification, alongside partial degradation of polar groups, surface activation, and the formation of new carbonyl functionalities.

Hydrothermal liquefaction (HTL) uses compressed water at high temperatures (≥250 °C) to convert wet biomass into a synthetic crude oil (bio-crude). Here, sugarcane bagasse was treated in batch mode using water, ethanol, and a water+ethanol (1:1, w/w) mixture at a 1:9 biomass-to-solvent mass ratio to evaluate the effects of solvent, non-isothermal heating, temperature (180, 210, and 240 °C), and holding time at the setpoint temperature (0 to 60 min) on product distribution under pre-HTL conditions. With water at 240 °C and 60 min holding time, solid recovery was 48% and non-volatile liquor products were 16%. Under the same conditions, the water+ethanol mixture improved fractionation, yielding the highest extraction (35%) and the lowest solid recovery (36%). Ethanol addition inhibited humins formation and favored lignin and hemicellulose fractionation (solid recoveries of 27% and 1% at 240 °C and 60 min), while 56% of glucans remained in the residual solids. Under the best sugar recovery treatment (water, 180 °C, 0 min), 62% of hemicelluloses were recovered in the liquor at a 1:6 mono-to-oligosaccharide ratio. Under harsher conditions, even in the presence of ethanol, slow heating promoted depolymerization but also substantial sugar degradation, with acetic acid being identified as the main component of liquid streams.

The combined effects of grain orientation and CNC end milling parameters on wood surface quality remain poorly understood. This study investigated the surface quality of tangential oak during frontal milling and radial oak during peripheral milling using straight-flute end mill tools with diameters of 8 and 10 mm, four stepover values (30%, 50%, 70%, and 90% of the tool diameter), and two cutting depths (1 and 3 mm). Surface quality was evaluated through roughness parameters and profiles, microscopic observations, and compared with reference surfaces obtained by shaving and P150 sanding. ANOVA revealed that stepover is the primary factor governing roughness, followed by tool diameter, while cutting depth had no statistically significant impact. Increasing the stepover beyond 50% substantially degrades the surface due to severe fiber lifting and tool ridges. The 8 mm tool produced smoother surfaces than 10 mm tool, in both milling operations and at 30% stepover closely approached the ideal shaved baseline. In frontal milling, stepovers of 30% and 50% outperformed sanding, whereas in peripheral milling, only the 8 mm tool yielded superior quality. Utilizing a smaller tool diameter at a low stepover ratio guarantees a finish-ready surface directly from the CNC machine.

Bio-based polyols derived from lignocellulosic biomass have attracted considerable attention as sustainable alternatives to petroleum-based polyols in polyurethane production. In this study, spruce sawdust was liquefied using pretreated crude glycerol (PCG) and pretreated crude glycerol/polyethylene glycol (PCG/PEG) binary solvent systems under acid-catalyzed conditions to produce bio-polyols. The effects of reaction temperature, reaction time, and solvent composition on biomass conversion, hydroxyl number, acid number, and viscosity of the resulting polyols were systematically investigated using response surface methodology (RSM). Liquefaction experiments were conducted at temperatures ranging from 100 to 180 ºC for PCG and 120 to 200 ºC for PCG/PEG mixtures, with reaction times between 40 and 360 min. The results demonstrated that increasing temperature, reaction time, and PEG content significantly enhanced biomass conversion efficiency. Statistical analysis confirmed that temperature and reaction time were the most influential parameters affecting polyol properties and liquefaction performance. The incorporation of PEG improved biomass conversion and reduced viscosity compared with PCG alone. The obtained bio-polyols exhibited physicochemical characteristics within the range generally considered suitable for rigid polyurethane foam polyol formulations, demonstrating the potential of PCG and lignocellulosic waste as sustainable feedstocks for high-value polyurethane materials.

Biogenic synthesis using plant materials provides a sustainable alternative to classical nanoparticle fabrication, minimizing chemical hazards and decreasing energy input. In this study, silver nanoparticles (AgNPs) were prepared using an aqueous extract of Mercurialis annua and characterized. Physicochemical properties of the AgNPs were confirmed using ultraviolet–visible spectroscopy (UV–Vis), Fourier transform infrared (FTIR) analysis, X-ray diffraction (XRD), and transmission electron microscopy coupled with energy-dispersive X-ray (TEM–EDX), which collectively indicated crystalline, spherical silver nanoparticles stabilized by extract-derived functional groups. Subsequently, the biological activities of both the nanoparticles and the extract were comparatively evaluated using antioxidant tests, including cupric ion reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), total phenolic content (TPC), and total flavonoid content (TFC), as well as enzyme inhibition tests targeting α-glucosidase and carbonic anhydrase. Liquid chromatography-mass spectrometry profiling identified 31 phenolic constituents in the extract, with ferulic, caffeic, salicylic, and 4-hydroxybenzoic acids detected in high abundance. Overall, the biosynthesized AgNPs demonstrated higher antioxidant performance and stronger inhibitory effects on both enzymes compared with the crude extract. These results indicate that M. annua-based AgNPs hold considerable promise sustainable and effective bioactive agents for future biomedical and biotechnological applications.

In the context of Kazakhstan’s strategy to achieve carbon neutrality by 2060, assessing transport-related CO₂ emissions associated with imported timber supply has become increasingly important. For Kazakhstan, this issue is particularly relevant for Kazakhstan because its woodworking industry depends heavily on imported timber transported over long distances. The objective of this study was to assess CO₂ emissions generated during the transportation of imported sawn timber to Kazakhstan, through a comparative analysis of transport-related CO₂ emissions under different logistics scenarios and a comparison of logistics scenarios. The study considers three logistics supply scenarios: rail transport, road transport, and a combined scenario (rail transport followed by a road segment). Calculations were based on a distance-oriented model using average emission factors consistent with international databases. One tonne of sawn timber is adopted as the functional unit. The results showed that rail transport provides the lowest emission level (62 kg CO₂/t), whereas road transport generated substantially higher transport-related CO₂ emissions (153 kg CO₂/t). The combined scenario demonstrates an intermediate value (148.5 kg CO₂/t), indicating the substantial influence of the road transport share on total emissions.