Band 80, Heft 4

Replication of brown-rotted wood is essential for researchers across disciplines who require suitable and reliable substrates for laboratory experiments. While enzymatic protocols are commonly used, their inherent heterogeneity limits reproducibility and compromises replicate consistency. As a result, researchers are turning to non-enzymatic protocols, particularly the Chelator-Mediated Fenton (CMF) reaction. Although these protocols are successful, they are typically evaluated based solely on the chemical properties of decayed wood, while other key properties remain largely unexamined. This study therefore aimed to examine the physical and mechanical properties of CMF-treated wood, alongside its chemistry, to evaluate its suitability as a reliable substrate for laboratory studies. Scots pine ( Pinus sylvestris L.) samples were CMF-treated and analyzed chemically by ATR-FTIR spectroscopy, mechanically through Shore D hardness and micro three-point static bending tests, and physically by measuring equilibrium moisture content, apparent density, mass loss, and color. For comparison, samples decayed by the brown rot fungus Coniophora puteana were also examined. Results showed that CMF-treated samples closely mimic fungal decay, exhibiting selective polysaccharide depolymerization, pronounced mechanical strength loss, and distinctive physical and morphological changes. These findings demonstrate that non-enzymatic decay protocols can reliably replicate the physicochemical and mechanical properties of brown-rotted wood, offering consistent substrates for experimental research.

The research aimed to evaluate the effect of transferring extracts from residues of durable Amazonian wood species processing to a non-durable wood species (rubber tree) to prolong its use. For this purpose, three trees of rubber tree (27 years old) were collected from Santa Maria farm in the district of Pacotuba, Cachoeiro de Itapemirim, south of the state of Espírito Santo, Brazil. These trees were transformed into samples for testing basic density, dimensional stability, retention and pH of the extracts, and resistance of the samples impregnated with the solutions obtained to xylophagous fungi. The impregnation of the wood was carried out using alcoholic extracts (solutions) of Hymenolobium flavum , Roupala montana, Dinizia excelsa , and Tectona grandis . The rubber tree wood had a medium density and moderately stable dimensional stability. The extracts were used in concentrations of 2, 4 and 8 % and tested against brown-rot fungi ( Rhodonia placenta and Neolentinus lepideus ) and white-rot fungi ( Polyporus fumosus and Trametes versicolor ). The extracts exhibited acidic pH (3.5–6.1), which contributed to the effectiveness against the tested fungi. The extracts of R. montana and T. grandis , at concentrations of 4 and 8 %, were more effective in controlling the development of xylophagous fungi.

Mechanosorptive creep strain (MCS) is a strain component that can dominate the overall deformation behavior of wood components under load and changing moisture. In this work, the MCS behavior of Norway spruce ( Picea abies ) tissues is investigated in the anatomical directions perpendicular to grain and different loading degrees (LD). The MCS is evaluated through a strain decomposition of the total strain, which is determined using a computer-controlled digital image correlation (DIC) system. It is shown that the common assumption of a scalar relation between mechanosorptive creep compliance (MCC) and the orthotropic, moisture-dependent elastic one is questioned by experiments.

This study investigated depth-dependent microbial degradation in waterlogged archaeological wood using an integrated analytical approach combining maximum water content (MWC), X-ray diffraction (XRD), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and light microscopy. These methods were systematically applied to increment cores extracted from three hull logs (left bottom log 3-3, right bottom log 1-1, and right bottom log 2-1) recovered from the Mado shipwreck No. 2 (AD 1151–1224) in the Yellow Sea, Republic of Korea. Logs 3-3 and 1-1 were normal wood, whereas log 2-1 was identified as compression wood. Each core was sectioned at approximately 1 cm intervals from the surface inward, and all analyses were conducted on the same depth-resolved sections, enabling direct comparison among physical, chemical, and anatomical indicators. This approach successfully delineated degraded zones, revealing consistent relationships among elevated MWC values, reduced crystallinity, ATR-FTIR evidence of polysaccharide loss and lignin enrichment, and microscopic signs of microbial attack. Degradation depths varied markedly among logs (approximately 4–5 cm in log 3-3, 9–9.5 cm in log 1-1, and ∼1 cm in log 2-1), underscoring the need for log-specific evaluation, even within a single shipwreck, for accurate assessment of preservation states and effective conservation planning.

Lignin-based carbon fibers (LCFs) offer a promising route for both the high-value utilization of underused lignin and the development of green, low-cost electrode materials for supercapacitors. However, achieving high energy density while maintaining power density and long-term cycling stability remains a major challenge for LCF-based supercapacitors. In this study, a series of Ni/P co-doped LCFs were prepared via electrospinning, thermostabilization, and carbonization, without additional activation steps. Nickel acetylacetonate (Ni(acac) 2 ) was incorporated to enhance the thermal stability of lignin fibers during thermostabilization and to facilitate catalytic graphitization during carbonization. Phosphoric acid (H 3 PO 4 ) was introduced at various stages to tailor pore architecture, enhance surface activity, and further promote graphitic structure development. Furthermore, co-doping with Ni and P at 1,400 °C enabled the in-situ formation of Ni 2 P, which contributed additional pseudocapacitance. Benefiting from the integrated structural and compositional design, the resultant supercapacitor based on P-LSF-1400 delivered an excellent electrochemical performance, achieving a specific capacitance of 156.4 F g −1 , an energy density of 48.9 Wh kg −1 , and a power density of 802 W kg −1 , with 95 % capacitance retention after 5,000 cycles. This synergistic strategy places P-LSF-1400 well above most carbon-based electrodes derived from biomass, highlighting its strong potential for practical energy storage applications.

Understanding the structural characteristics of vascular bundles is fundamental to improving the performance of bamboo-based materials. Here, an image-processing-based intelligent model for bamboo culm cross-sections was developed, implementing bamboo contour extraction, vascular bundle identification, polar-coordinate construction, and morphological feature extraction. The model precisely estimated the vascular bundles’ position, length, width, aspect ratio, fiber-sheath area, and deflection angle. It demonstrated high accuracy and stability, supporting batch analysis of the geometric dimensions of cross-sectional vascular bundles. Radially, bundles at the inner skin were nearly circular, while those in the middle part of the culm wall were elongated and larger. At the outer skin, size decreased and tended toward circularity, with greater individual variability. The deflection angle decreased monotonically from the inner skin to the outer skin. Circumferentially, the area and length showed minimal variations. The widths at the inner skin and in the middle section change little, whereas the outer skin was wider near the long-axis and short-axis and thinner in inter-axial regions. The aspect ratio displayed an inverse relationship to the width, with periodic and symmetrical variations. These results provide data support for the structural analysis of bamboo materials as well as for the design and application of biomimetic materials.

Ultrasonic pretreatment offers a green strategy to modify bamboo structure and improve dimensional stability. However, power/intensity-threshold effects of ultrasonic pretreatment on microstructural remodeling and dimensional stability in moso bamboo ( Phyllostachys edulis ) remain unclear. In this study, moso bamboo was treated at powers ranging from 0 to 400 W (0–2.522 W cm −2 ) to evaluate changes in microstructure, chemistry, and hygroscopic properties. Results showed that above 360 W (2.2 W cm −2 ), luminal deposits and pit membranes were greatly removed; parenchyma double-wall thickness decreased by up to 15.1 %, while mass loss rose by up to 36.2 %; crystallinity increased by 18.5 %. ATR–FTIR showed attenuation of hemicellulose and lignin bands, suggesting leaching of amorphous components during ultrasonic treatment. Microfibril angle decreased at moderate intensity and partially recovered at higher levels. These microstructural and physicochemical changes resulted in improved dimensional stability, with a reduction of approximately 0.74 % in radial swelling (360 W, 2.236 W cm −2 ), despite a slightly higher moisture uptake. These results indicate that the response intensifies in the ∼360 W region, suggesting a practical threshold region for balancing structural debridement, chemical refinement, and dimensional stability in bamboo. Ultrasonic pretreatment thus holds promise for enhancing performance in bio-based composites and engineered bamboo products.