Volume 21 Issue 1

Flowability is an essential property that must be evaluated to ensure smooth and consistent feeding of powder materials into hoppers. It can be influenced by particle shape, size and its distribution, and surface chemical characteristics. In the case of cellulose powders, their physical and chemical properties are not uniform and can vary depending on the cellulose source and powder preparation method. In this study, the flowability of cellulose powders was evaluated through static and dynamic analyses. The angle of repose was measured to assess static flow characteristics, while avalanche behavior was analyzed using a revolution powder analyzer. Cellulose nanofiber, microcrystalline cellulose, and milled kenaf pulp were classified by particle size to investigate the effects of morphology. Larger and more spherical particles exhibited superior flowability, whereas particles smaller than 70 µm showed a sharp decline in flowability. Particle size had a stronger influence than size distribution. Increasing moisture content improved the flowability of fine particles but reduced that of coarse ones. Moderate hydrophobization enhanced flowability by reducing surface energy, whereas excessive treatment caused deterioration due to aggregation. These results identified the key parameters governing cellulose powder flow and clarified the characteristics advantageous for stable feeding and uniform product quality.

To reduce the energy consumption of biomass densification, this study proposes a method of constructing solid bridges through pressurized binder spraying. The feasibility of this method for producing high-quality biomass molding was studied under ambient temperatures and lower pressures. Four-factor mixed-level orthogonal tests were designed to evaluate the relaxation ratio and durability of density pellets, in which the molasses served as the binder. Pressurized spraying of the binder resulted in a 27.0% increase of relaxation density, 8.21% decrease in relaxation ratio, and significantly enhanced durability compared to stirring method at pressure 40 MPa, which was determined in preliminary testing to conform to at least 95% durability. A multivariate quadratic regression equation through response surface analysis was established by selecting a 2FI model for the 100% importance in binder addition method. The relaxation ratio was normalized to the weights of the influencing factors obtained from model of multi-layer perceptron neural network. The test factors had a significant impact of on the relaxation ratio, and thus, the optimal combination condition for test was determined as 50 (MPa) densification pressure, 14% moisture content, 4% binder ratio, and pressurized spraying at 2 (MPa). These conditions reduced the minimum densification pressure required for biomass densification.

The biosynthesis of Reduced Graphene Oxide (RGO) was shown using an aqueous leaf extract of Rhododendron micranthum Turcz. as a reductant by deoxygenation of Graphene Oxide (GO). The reduction of GO to RGO was shown as a shift in UV-Vis peak from 230 nm to 270 nm. X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Raman spectroscopy confirmed the GO reduction. Thermal gravimetry and zeta potential measurements exhibited the good stability of RGO. Transmission Electron Microscopy (TEM) results showed thin and transparent RGO sheets. Cell viability results showed that the mesenchymal stem cells (MSCs) of adult goats were viable in the presence of RGO at a concentration of 0.1 mg/mL, and their properties were retained. The analgesic effect of RGO was assessed in mice through the oral administration of different doses of RGO. Writhing episodes induced by acetic acid were decreased dose-dependently. Also, the inflammatory effect of RGO was shown by measuring the hind paw volume of rat exhibited the decreased inflammation with increased RGO concentration. The local anesthetic activity was assessed in guinea pig models and frog, revealing that the RGO exhibited a substantial local anesthetic effect in both the animals with decreased response in dose dependent manner.

Anaerobic co-digestion was evaluated for lignocellulosic materials and paper plant sludge cakes (PSL). The methane production, crystallinity, residual cellulose, and next-generation sequencing (NGS) were analyzed and compared. It was found that microcrystalline cellulose (MCC) had the highest accumulated methane production among the different materials in the anaerobic digestion system. The residual content and crystallinity of cellulose both decreased to a much larger extent, and the accumulated methane production was higher than that of the anaerobic digestion system with the added anaerobic sludge cake. NGS showed that the domain bacteria in the anaerobic digestion system with the added anaerobic sludge cake were Methanosaeta, which can convert organic sugars into methane. This substantially reduced the number of bacteria that can degrade cellulose. As the ability to degrade cellulose decreased, the residual cellulose content and crystallinity of cellulose became higher than those of the anaerobic digestion system without adding anaerobic sludge cake.

The hyper-cellulase producing bacterium Bacillus paramycoides strain BTH was isolated and characterized by 16S rRNA sequencing. Its potential for saccharification of Brachiaria mutica (para grass), a lignocellulosic aquatic weed, was examined. Cellulase production from strain BTH was enhanced by optimizing various parameters in the presence of goat dung as feedstock using One factor at a time (OFAT) and Response Surface Methodology (RSM) methods. The OFAT-based non-statistical method improved cellulase activity up to 1280.32±27.3 U/g. Box-Behnken Design of RSM-based optimization exhibited 1.3-fold enhancement in cellulase activity (1725.54±32.63 U/g) as compared to OFAT technique in the presence of goat dung medium (pH 8.0), incorporated with 1.5% (w/w) CMC and incubated at 37°C. Para grass biomass was further pre-treated via hydrothermal, alkali, acid, hydrogen peroxide, and microwave heating methods and subjected to strain BTH-associated cellulase-based hydrolysis. The alkali pre-treated biomass exhibited maximum total reducing sugar production of 6.73±0.2, 9.25±0.16, 11.6±0.17, 14.11±0.16, and 11.54±0.16 mg/g in the presence of 4% (w/v) NaOH from 12 to 96 h. Likewise, 4% (w/v) NaOH pre-treated biomass showed maximum saccharification efficiency of 30.28±0.8, 41.62±0.6, 52.2±0.7, 63.49±0.6, and 51.93±0.8% from 12 to 96 h. The findings validated the role of B. paramycoides-associated cellulase in the saccharification of para grass.

Biofilm-associated infections are a major medical problem that is responsible for nearly 80% of human microbial infections. These bacterial communities are protected by a strong extracellular matrix that limits antibiotic penetration and supports persister cells and quorum-sensing–driven resistance. Biofilm development occurs in several stages and ultimately forms complex structures that block antimicrobial action. To overcome this, chemical strategies include quorum-sensing inhibitors, matrix-degrading agents, antimicrobial peptides, and photodynamic therapy. Biological approaches use bacteriophages, enzymes such as DNase, and probiotics that disrupt biofilms through competitive mechanisms. Combination therapies—such as antibiotic-phage or enzyme-antibiotic treatments—show improved effectiveness. Advanced delivery systems involving nanoparticles, liposomes, and hydrogels enhance drug penetration in biofilms, particularly in wound care. New technologies, including AI-guided drug discovery and CRISPR targeting, are advancing future anti-biofilm treatments.

Esterified wood was produced from beech (Fagus orientalis Lipsky) using acetic anhydride via a soaking-impregnation process with varying impregnation (Im) and reaction (Re) durations. Oven-dried beech wood samples were immersed in acetic anhydride for either 60 or 180 minutes.The samples were then wrapped in foil and placed in an oven at 103 ± 2 °C for 60 or 120 minutes to facilitate the acetylation reaction. The weight percent gain (WPG) was determined to assess the extent of the chemical modification. Flexural strength (FS), flexural modulus (FM), impact strength (IS), and compression strength (CS), along with water absorption (WA), thickness swelling (TS), and anti-swelling and anti-shrinkage efficiencies were evaluated. The WPG increased with increasing reaction, reaching 9.1% for Im60-Re60 and 13.6% for Im180-Re120 treatments. Acetylation significantly reduced water absorption and dimensional changes compared with untreated wood. Higher WPG levels resulted in reductions in FS and IS, whereas FM and CS were not significantly affected. Among the tested conditions, the Im60-Re60 treatment provided the most balanced performance, achieving improved dimensional stability with minimal reduction in mechanical properties. These results demonstrate that controlled acetylation can enhance the moisture resistance and dimensional stability of beech wood while maintaining acceptable mechanical performance.

Current numerical models for timber components are often limited to single constitutive theories, making it difficult to accurately simulate their complex multi-stage mechanical behavior under diverse service conditions. To overcome this limitation, this study proposes an innovative “multi-model collaborative finite element analysis method.” Guided by the principle of “service-condition matching,” this method dynamically selects and integrates appropriate mechanical models to achieve high-fidelity simulation throughout the entire service life of the component: an orthotropic elastic model is used to reveal the “strong longitudinal but weak transverse” stress distribution under normal loads; the Hill anisotropic criterion captures the evolution of plastic strain as loads approach the yield point; and a viscoelastic model describes the rate-dependent and stress-relaxation behaviors under long-term loading. Results show that the collaborative method effectively elucidates the respective mechanical mechanisms, and Digital Image Correlation (DIC) measurements validate the simulation accuracy. The proposed method provides an innovative and efficient cross-scale numerical tool for timber structures, enabling integrated simulation from short-term safety assessment to long-term performance evolution. This is of great significance for the conservation, performance optimization, and lifespan prediction of historic timber components.

A simple manufacturing strategy was developed to fabricate cross-banded jute stick boards using citric acid (CA). The effects of CA concentrations and pressing temperatures on the physical and mechanical properties of the boards were systematically investigated. Jute sticks were impregnated with CA concentration ranging from 20 to 60 wt% and hot-pressed at 160 to 220°C at a pressing pressure of 5 MPa. Boards treated with 40 wt% CA exhibited the highest modulus of rupture (53.6 N/mm²) and internal bond strength (0.52 N/mm²), while those treated with 60 wt% CA showed superior dimensional stability, with a thickness swelling of 14.7% at a pressing temperature of 200 °C. Fourier transform infrared spectroscopy analysis confirmed the formation of ester linkages between the carboxyl groups of CA and the hydroxyl groups of jute stick components, resulting in strong chemical bonding and interfacial adhesion. Therefore, by optimizing the processing parameters, CA-treated jute stick crossbanded board was successfully developed with enhanced mechanical strength and dimensional stability.

Forty-eight naturally growing Viburnum opulus L. genotypes were collected from the Sarıoğlan, Felahiye, Melikgazi, and Kocasinan districts in Kayseri province, and characterized for morphological and horticultural traits. Fruit width (7.3 to 11.6 mm), fruit length (8.2 to 12 mm), fruit weight (0.3 to 0.8 g), number of fruits per cluster (18 to 111) and cluster weight (10 to 78 g) exhibited significant heterogeneity among the genotypes. Soluble solids content ranged from 7.5% to 11.6% and pH values ranged between 2.6 and 3.7. Oxalic acid content ranged from 221 to 779 mg/100 mL, malic acid from 8.6 × 10³ to 1.4 × 10⁴ mg/100 mL, citric acid from 8.4 × 10² to 2.7 × 10³ mg/100 mL, and ascorbic acid from 544 to 919 mg/100 mL. Total phenolic content was 1.8 × 10³ to 2.0 × 10³ mg/L GAE, total flavonoid content 1.2 × 10³ to 2.0 × 10³ mg/L QUE, and antioxidant activity remained relatively stable, ranging from 83.00% to 85.03% with a mean of 84.42. Principal component analysis (PCA) and hierarchical clustering revealed relationships between morphological and biochemical traits. Correlation analyses indicated strong positive associations between fruit size and cluster characteristics. Phenolic compounds and vitamin C contents are the primary factors determining antioxidant capacity. The results highlight the importance of genetic diversity and provide a foundation for breeding, selection, and sustainable utilization efforts.