Research Articles

The aim of this study was to demonstrate the utilization of invasive plant materials a resource for energy production, applying pelletization and pellet pyrolysis, thus integrating plant eradication efforts with renewable energy solutions and valorization of plant biomass. The approach was demonstrated for three invasive plants – Japanese knotweed [Reynoutria japonica (Houtt.)], Jerusalem artichoke [Helianthus tuberosus (L.)], and Canadian goldenrod [Solidago canadensis (L.)] which are abundant in Northern Europe and elsewhere. As binder materials for pellet formation, sapropel and peat extraction residues were selected for their sustainability potential, as both represent organic waste materials that, similarly to invasive plant biomass, face a high likelihood of being disposed of without added value if not valorized. The calorific value of biomass plant pellets is comparable to values common for wood pellets and other plant materials, thus supporting their use for energy production. Pyrolysis provides possibilities to obtain biochar with increased specific surface area and higher caloric content, as well as application potential in agriculture. The studied invasive plant pellets do not contain elevated concentrations of heavy metals or other pollutants, thus supporting their application for the production of bioenergy or as a soil amendment.

Using an electron beam (EB) accelerator, natural cotton fibers were pre-irradiated for grafting with glycidyl methacrylate (GMA). Subsequently, phosphoric acid (phosphoric) was used to functionalize the GMA-grafted fibers (cotton-g-GMA). Various analyses, including scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric and derivative thermogravimetric (TG-DTG) analysis, and surface charge analysis, were performed to evaluate the morphological and physiochemical attributes of the fibrous adsorbent. The prepared adsorbent was then tested for metformin hydrochloride (MFH) adsorption from an aqueous solution. The MFH’s adsorption on phosphoric-cotton-g-GMA followed a pseudo-2^nd order model. The Langmuir isotherm model was close behind the Redlich-Peterson model, which described the equilibrium data the best, according to the isotherm analysis. At 24.7 mg/g, the maximum adsorption capacity was attained. Meanwhile, the regeneration and recycling of the adsorbent were possible for at least five cycles, with recovery of MFH being nearly 94.65% in the final cycle. According to the findings, it was deduced that the fibrous phosphoric-cotton-g-GMA adsorbent could be used to successfully eliminate MFH at an industrial scale.

Recyclability is an important feature of packaging materials. Although packaging materials made from cellulose fibers such as those found in paper or paperboard can typically be recycled through repulping, the application of coatings, especially polymeric plastic coatings, often impairs their recyclability, leading to increased amounts of rejects and low fiber yields. Herein, the surface properties and repulpability performance of paperboard substrates coated with aqueous dispersion of wood bark-derived suberin, stabilized using synthetic surfactants or bio-based surfactants, were investigated. The results were compared with commercial polyethylene coated material. Surface properties of the materials were investigated through surface imaging, water absorption, and wettability measurements. Repulpability was evaluated based on the amounts of rejects after two screening stages. Fiber analysis was performed for the materials that passed both the screenings. All suberin-coated materials showed hydrophilic surface characteristics and greater water absorbency than the reference material. Repulpability analysis revealed that the suberin coatings resulted in a lower amount of rejects than coated reference material. These results highlight the potential of suberin coatings in developing recyclable and sustainable packaging solutions for cellulose fiber substrates.

To enhance the uniformity and efficiency of rice drying, an infrared hot air combined drying test bench was developed, and the air flow distribution inside the pipeline was optimized to achieve efficient and uniform drying. The pipeline structure was optimized by using computational fluid dynamics simulation technology, with relative standard deviation (CV) and uniformity index (UI) as evaluation indicators. The airflow uniformity of the optimized pipeline and the temperature uniformity of the drying chamber were verified through experiments. The numerical simulation results showed that after the structural optimization, the UI of the pipeline outlet was increased from 92.27% to 97.23%, and the CV was decreased from 22.34% to 14.62%. Experimental verification shows that the wind speed uniformity index of the optimized pipe section is 97.67%, which is in good agreement with the simulated value (the relative error of the average speed is 1.50%), and the temperature change in the drying chamber is stable within ±2.5%. Further drying performance tests were conducted on two types of rice. Under the conditions of a hot air temperature of 45℃, a wind speed of 3 m/s, and a thin layer thickness of 20 mm, the performance of infrared hot air combined drying and hot air drying was compared. The performance test results show that the infrared hot air combined drying only takes 120 minutes, which is 18.75% shorter than the single hot air drying time, and still maintains a relatively high drying rate during the deceleration and dehydration stage. Improving the uniformity of air flow distribution can significantly enhance the uniformity of drying. Infrared hot air combined drying has good application potential in terms of improving efficiency and energy conservation.

Banana pseudostem (Musa sp.) fibers from 10 Indonesian cultivars were evaluated as candidate renewable sources for biomaterial development. Their physical properties (density and moisture content), mechanical strength (tensile strength and elastic modulus), and chemical composition, including lignin, holocellulose, α-cellulose, and hemicellulose content levels were analyzed. Pyrolysis–gas chromatography-mass spectrometry (Py-GC/MS) was employed to determine the syringyl-to-guaiacyl (S/G) ratio, providing insights into the lignin structure. Among the samples, D20 (Cavendish) showed consistent performance characterized by its high holocellulose content (52.2%), substantial α-cellulose fraction (33.3%), and superior mechanical strength, with a tensile strength of 166 MPa and an elastic modulus of 4480 MPa. Accordingly, this cultivar was selected for further investigation. Fourier transform infrared (FTIR) spectroscopy confirmed the presence of functional groups characteristic of lignocellulosic biomass, including hydroxyl, carbonyl, aromatic, and glycosidic linkages. X-ray diffraction (XRD) analysis revealed semicrystalline cellulose, while scanning electron microscopy (SEM) indicated a compact fiber structure with a defined lumen and minimal surface degradation. These findings suggest that fibers from D20 exhibit a promising balance of chemical, structural, and morphological characteristics, supporting their suitability for bio-based composite applications. Overall, this research emphasizes the underutilized potency of local banana waste as a foundation for sustainable material innovation.

Severe complications arise from fungal infections by Candida species. The antifungal properties of single and mixed essential oils (EOs) of Corymbia citriodora, Rosmarinus officinalis, and Lavandula stricta, as well as five pure components, against Candida species were explored. A total of 43 clinical Candida species were clinically isolated and identified as test subjects. The combination of L. stricta and R. officinalis oils mixture showed the highest activity, displayed from the inhibitory zones of 19.4 mm against Candida tropicalis (18K). The highest activity of citronellol with linalool mixtures was 19.4 mm in C. albicans (551). The highest activity of the combination of C. citriodora oil with camphor, linalool, and α-pinene mixture against C. parapsilosis (20K) was 21.9 mm. The minimum inhibitory concentrations (MICs) of C. citriodora oil combined with citronellol, linalool, and α-pinene against clinically isolated C. parapsilosis (20K), C. albicans (551), and C. tropicalis (18K) were 0.06, 0.24, and 0.98 μg/mL, respectively. Also, mixing these oils inhibited germ-tube formation in C. albicans as compared with the individual oil at the same concentration. The results emphasize the synergistic capabilities of mixtures as antifungal agents, presenting a promising path for creating new therapies from natural sources against Candida-based infections.

In environmental impact assessments of buildings, the steel used in wooden structural connections, which are responsible for sustaining shear and tension stresses, is often overlooked yet could account for up to 13% of the total environmental impact over a building’s lifecycle. This study assessed the importance of end-of-life management on the environmental impact of a hypothetical glued-laminated timber post-and-beam commercial building in Québec (Canada). The study used Life Cycle Assessment (LCA) and the SimaPro software, the EcoInvent database, and the TRACI impact assessment method. Assessing solely post-and-beam connections, LCAs were conducted at three scales, comparing 5 structural connections. Using heavy steel or aluminum structural connections leads to an impact of nearly 3% on global warming potential. It was found that the exclusion criteria used to simplify LCAs cannot be applied to structural connections. Multi-scale comparison of the connections—from individual component performance to their integration within the full building system—revealed significant variability in environmental outcomes. The study compared an improved end-of-life scenario with the current end-of-life scenario in Québec. The results showed a 7% reduction in the Climate Change impact category at the building scale. Early-stage design directions can affect end-of-life potentialities and practices with wood-building construction.

Injectable self-healing hydrogels are promising biomaterials for wound management, as their ability to autonomously repair enables conformal sealing of irregular wounds. In this study, an injectable hydrogel was fabricated through Schiff base cross-linking of acrylamide-modified chitosan (AMCS) and 50% oxidized alginate (ADA). To enhance its mechanical robustness and hemostatic performance, chitin nanogels (CNGs) were incorporated as a reinforcing component. The structure-property relationships of the resulting hydrogel were characterized using infrared spectroscopy, field emission scanning electron microscopy, confocal laser scanning microscopy, and rheological analysis. Rheological studies confirmed that the composite hydrogel (AANGH) exhibited a superior storage modulus and more robust self-healing recovery compared to the base hydrogel (AAH3). MTT assays using L929 fibroblast cells demonstrated outstanding cytocompatibility, with cell viability maintained at over 100%. Furthermore, in vivo hemostatic assessment demonstrated effective hepatic hemorrhage control, characterized by significantly reduced blood loss, shortened hemostasis time, and favorable antibacterial properties. This work establishes that AANGH is an effective strategy for creating a mechanically robust, self-healing, and highly biocompatible chitosan-based hydrogel with strong potential for hemostatic applications.

Wood treatments involving chemical reactions are increasingly common in the construction industry, with acetylation being one of the most widely applied methods. In this study, European beech wood (Fagus sylvatica L.) was modified using acetylation in both traditional liquid phase (LP) and gas phase (GP) under varying temperatures (100 to 130 °C) and reaction times (1 to 4 h). The two methods were compared based on weight percentage gain (WPG), bulking coefficient (BC), water-related properties, and chemical changes confirmed by Fourier transform attenuated total reflectance infrared (FTIR-ATR) spectroscopy. The results showed that LP acetylation achieved the highest WPG (19.6%), while GP acetylation provided comparable results under higher temperatures and extended reaction times. Both methods significantly reduced equilibrium moisture content, water absorption, and volumetric swelling, thereby enhancing dimensional stability compared to reference (REF) samples. FTIR analysis confirmed substitution of hydroxyl groups by acetyl groups in both phases. Despite slightly lower WPG values in some regimes, GP acetylation provided similar improvements in water-related properties with reduced consumption of acetic anhydride (AAH). This indicates its strong potential for industrial applications, although further research is necessary to optimize the process for large-scale European beech wood components.

This study investigated the production of particleboards by incorporating recycled polyethylene terephthalate (PET) powder into Pinus spp. particles, using epoxy resin as an adhesive at 5% and 10% levels. The panels were manufactured and tested in accordance with ABNT NBR 14810-2 (2024) and further evaluated under EN 312 (2003) and ANSI A208.1 (2016) standards. The results demonstrated that both the increase in adhesive content and the incorporation of PET powder contributed to significant improvements. Compared with literature data on panels without PET, the addition of recycled PET reduced moisture content (MC), thickness swelling (TS), and water absorption (WA) by about 29% and promoted mechanical gains of up to 33% in modulus of elasticity (MOE), 31% in modulus of rupture (MOR), and 133% in internal bond strength (IB). Increasing epoxy from 5% to 10% further enhanced performance, with reductions of 46.3% in TS and 49% in WA after 24 h, and increments of 57.1% in MOR, 68% in MOE, and 104.3% in IB. Scanning electron microscopy confirmed improved encapsulation of wood and PET particles with 10% adhesive. These findings point to a viable circular-economy route by upcycling plastic waste and wood residues into higher-value particleboards while avoiding added formaldehyde.