Search Results (3,106)

This study developed an active packaging material by incorporating tea tree oil (TTO)-loaded lotus stalk biochar (BC@TTO) into a chitosan (CS) matrix. Biochar was prepared from lotus stalks via pyrolysis at 600 °C and characterized, revealing a mesoporous structure with a specific surface area of 35.9 m²/g. Adsorption studies demonstrated that BC exhibited high affinity for TTO, following pseudo-first-order kinetics and the Langmuir isotherm model, with a maximum adsorption capacity of 295.6 mg/g. Chitosan-based composite membranes with varying BC@TTO contents (1–7 wt%) were fabricated by solution casting. The incorporation of BC@TTO significantly enhanced the tensile strength, elongation at break, barrier properties (water vapor and oxygen), and antioxidant/antibacterial activities of the membranes, with optimal performance observed at 3 wt% loading. However, higher loadings led to filler aggregation, reduced transparency, and compromised mechanical properties. In vitro release studies indicated that TTO release followed the Avrami model, suggesting a diffusion-controlled mechanism. Preservation tests on blueberries showed that the CS-3BC@TTO membrane effectively reduced weight loss and maintained fruit quality during storage. This work presents a promising strategy for designing bioactive packaging materials with sustained release functionality for food preservation applications. Full article

Selective laser melting (SLM) is a complex additive manufacturing process involving rapid laser–material interaction, steep thermal gradients, and phase change phenomena. In this work, a two-dimensional thermal model based on the lattice Boltzmann method (LBM) is developed to simulate the SLM process of AlSi10Mg and 316L stainless steel (316L SS) alloys. The model captures the laser–material interaction, layer-by-layer deposition, phase change behavior, and heat transfer mechanisms, including conduction and convection. Experimental observations of melt pool width and depth were also performed on the microstructures of the two SLM alloys in order to compare the results with the numerical predictions. For the AlSi10Mg alloy, good agreement is obtained, with relative errors of 19.13% in melt pool width and 7.58% in depth, accurately capturing melt pool penetration and remelting behavior. In contrast, moderate deviations are observed for 316L SS, indicating a higher sensitivity to thermophysical properties and suggesting that further model refinement is required. Overall, the results demonstrate the capability of the LBM framework as an efficient and robust tool for analyzing thermal behavior in SLM and for supporting process parameter optimization. Full article

The valorization of industrial waste in agriculture represents a key strategy within the circular economy framework. In this context, the present study aimed to assess the feasibility and potential of fertilizers derived from black mass, a by-product of alkaline battery recycling, as alternative sources of Zn and Mn in citrus cultivation, evaluating their effects on fruit quality and food safety. The experiment was conducted in Pedreguer (Alicante, Spain) in ‘Navelina’ cultivar using Carrizo and C-35 rootstocks, comparing conventional fertilization with black mass-based formulations applied as sulfates (BMSs) and lignosulfonates (BMLSs). The results showed that the evaluated micronutrient sources significantly increased foliar Zn concentrations up to 17.9 mg·kg⁻¹ and Mn concentrations up to 28.1 mg·kg⁻¹, values markedly higher than those observed in the Control treatment (15.20 mg·kg⁻¹ Zn and 11.5 mg·kg⁻¹ Mn). No adverse effects on yield or fruit quality were detected: Average fruit weight remained close to 200 g per fruit, and the proportion of non-marketable fruit did not exceed 2% in any treatment. Regarding food safety, Pb, Cr, and Ni concentrations in pulp and peel were below the maximum levels established by European Union regulations, with maximum values of 0.02 mg·kg⁻¹ for Ni and 0.04 mg·kg⁻¹ for Pb on a dry matter basis, while Cd, Co, and Hg were not detected. Overall, black mass-derived fertilizers enhanced Zn and Mn availability in plants without compromising plant physiology or fruit quality and maintained safe levels of heavy metals. These results support their use as a sustainable alternative for mineral fertilization in citrus orchards and reinforce their contribution to reducing the consumption of virgin raw materials and advancing toward more circular agricultural systems. Full article

Despite recent biotechnological advancements in the brewing industry, the effective valorization of spent grains from craft beer production remains challenging due to the nutritional variability of cereal-based raw materials. This study analyzes the proteins, free amino acids, fatty acids, and mineral composition of spent grains obtained from two beer types brewed with different proportions of maize grits and malted wheat, in order to assess the influence of adjunct composition. Protein content ranged between 25.81% and 28.43%, with higher values observed in the wheat-based spent grain. Total free amino acids were also higher in the wheat-based sample (190.03 mg/100 g) compared to the maize-based variant (178.66 mg/100 g). Both samples showed a similar fatty acid profile dominated by linoleic acid (51.39–51.58%), while phosphorus was the predominant mineral (up to 2700.03 mg/kg). These results suggest that adjunct type influences the nutritional characteristics of spent grains and provide a basis for their differentiated valorization in sustainable agri-food systems. Full article

The critical role of lithium in powering the new energy economy necessitates prioritizing efficient extraction methods. This study investigates a novel zeolitic imidazolate frame work (ZIF-8)-coated manganese-based lithium-ion sieve (LIS) for enhanced lithium recovery. The precursor of LIS, Li_1.6Mn_1.6O_4, was synthesized via the hydrothermal method, followed by acid pickling to obtain the spinel lithium-ion sieve H_1.6Mn_1.6O₄. The material was then immersed in a 2-methylimidazole/Zn(NO₃)₂ solution, undergoing ultrasonic-assisted hydrothermal growth to form H_1.6Mn_1.6O₄@ZIF-8 composites. Under optimized conditions (30 °C, pH = 11, 24 h), the composite demonstrated superior lithium extraction performance compared to single-phase adsorbents, reaching 26.62 mg/g in the solution with 250 mg/L Li⁺. The adsorption capacity of the composite increased with Li⁺ concentration and reaction time. The adsorption kinetics followed a pseudo-second-order kinetic model and were dominated by chemisorption. The H_1.6Mn_1.6O₄@ZIF-8 composite exhibited an enhanced Li⁺ partition coefficient K_d of 118.3 in a mixed solution containing ions such as Li⁺, Mg²⁺, K⁺, and Ca²⁺, each with a concentration of 250 mg/L (pH = 12); good structural stability with manganese dissolution of 1.6%; and a capacity retention of approximately 79.5% after five cycles (C_Li⁺ = 250 mg/L). Full article

Cr-based composite coatings with superior wear resistance are in growing demand for high-performance applications in the automotive, aerospace, and general manufacturing sectors. In this study, an Al10Cu alloy produced via powder metallurgy was coated with a chromium/nanodiamond (Cr/ND) composite layer using an electrodeposition process to enhance its tribological performance. The coatings were characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. The resulting Cr/ND layer exhibited a uniform thickness of 73.5–76.2 μm and markedly improved surface hardness (809.4 HV), representing a 15-fold increase over the uncoated alloy (53.6 HV). Pin-on-disk tribological testing under dry sliding conditions showed complete elimination of detectable mass loss (0.00 mg vs. 0.55 mg for uncoated) within the measurement system resolution, indicating excellent resistance to both abrasive and adhesive wear. XRD analysis revealed the formation of a hexagonal close-packed Cr₂H phase with incorporated nanodiamond particles. To capture and predict the temporal evolution of the friction coefficient, a customized dual-layer long short-term memory neural network—optimized with a look-back window of 3 timesteps and ReLU-activated dense layers—was implemented. The model achieved superior predictive performance on the coated system, with validation and test R² values of 0.9973 and 0.9965, respectively, demonstrating enhanced modeling accuracy for surface-engineered materials. These findings demonstrate a significant advancement in wear protection for aluminum alloys and introduce a robust data-driven approach for real-time friction prediction in engineered surfaces. Full article

Friction stir welding (FSW) is a key technology for manufacturing T-shaped thin-walled structures and avoiding fusion welding defects. However, the quantitative relationship between its process parameters and the microstructure properties of the joint remains unclear. To address this, this study established regression models via response surface methodology (RSM) relating rotational speed (w), welding speed (v), and plunge depth (h) to the mechanical properties of T-joints. The optimal process parameters (400 rpm, 60 mm/min, 0.21 mm) were determined, under which the ultimate tensile strength (UTS) and weld nugget hardness (WNH) of the joint reached 74.1% (377 MPa) and 94.4% (153 Hv) of the base materials (BM) respectively, with v showing the most significant influence on joint mechanical properties. Microstructural observations revealed that from the BM to the stirring zone (SZ), the grains underwent a continuous evolution from coarsening, partial recrystallization to complete dynamic recrystallization (DRX). In the SZ, due to severe plastic deformation and high heat input, the continuous dynamic recrystallization (CDRX) was the dominant mechanism, and the grain was significantly refined. The heat input in the thermomechanical affected zone (TMAZ) is relatively low, mainly geometric dynamic recrystallization (GDRX). DRX-driven grain refinement was the primary strengthening factor in the joint, with hardness closely related to grain size. However, thermal cycling induced softening in the heat-affected zone (HAZ) and promoted the precipitation of brittle compounds such as Al₃Mg₂ and MgZn₂, which caused crack initiation exhibiting intergranular brittle fracture. Subsequently, under stress drive, it extends to SZ, mainly characterized by ductile fracture. Full article

Lead-free double perovskites possess the capabilities of wide bandgap control, excellent photoelectric performance, and environmental friendliness. They are an ideal alternative system for addressing the heavy metal toxicity of lead-based perovskites and promoting their large-scale application. Precise control of their bandgap is key to the green transformation of optoelectronic devices. Bandgap, as a key parameter determining the photoelectric properties of materials, has limitations in traditional experimental determination and DFT calculation methods, such as being time consuming, labour intensive, costly, and difficult to achieve high-throughput screening. Deep learning provides an efficient solution to this problem, but current research has issues such as a single-model architecture and poor interpretability, which cannot effectively support bandgap regulation. This study utilised 2367 valid datasets of lead-free double perovskites sourced from the Materials Project database and relevant literature. Following preprocessing steps, including MinMaxScaler normalisation and Pearson correlation coefficient screening, the dataset was divided into a ratio of 7:1:2. The bandgap prediction capabilities of four models—MLP, deep ensemble learning, PINN, and Transformer—were systematically compared, with feature importance analysed using the SHAP method. The results show that the MLP model performs the best in medium-scale, structured feature prediction. The R² value of the test set is 0.9311, while the MAE, MSE, and RMSE are 0.1915 eV, 0.0975 eV², and 0.3122 eV, respectively. A total of 98% of the test samples have a prediction error of ≤0.4 eV, highlighting the stability of low bandgap systems. The Transformer is more suitable for large-scale, sequential feature prediction, while the MLP has limited generalisation ability for medium-to-high bandgap systems containing elements such as Si and Mg. The SHAP analysis revealed that the five electronic structure descriptors, such as B_HOMO+ and A_LUMO+, are the key influencing factors of the bandgap. The research results are helpful for the high-precision prediction and mechanism explanation of the bandgap of lead-free double perovskites, providing theoretical support for rational material design, performance optimisation, and bandgap-oriented regulation. They also point out the direction for subsequent model improvement. Full article

Bacterial and fungal infections, together with oxidative stress-mediated damage, remain major challenges in human health and in the protection of materials, highlighting the need for new multifunctional molecules that combine antioxidant and antimicrobial properties. In this context, a new chloropyridine-based derivative, N4,N4-bis((6-chloropyridin-3-yl)methyl)-N1,N1-diethylpentane-1,4-diamine (AMZ), was synthesized via a simple, catalyst-free N-alkylation of N1,N1-diethylpentane-1,4-diamine with 2-chloro-4-(chloromethyl)pyridine in acetonitrile at 55 °C, affording a 62% yield. The structure of AMZ was confirmed by melting point determination, ¹H and ¹³C NMR spectroscopy, and EI–MS analysis. Its antioxidant activity was evaluated using DPPH and FRAP assays with BHT as a reference standard, while antibacterial and antifungal activities were assessed via disk diffusion and microdilution methods to determine inhibition zones and MIC/MBC values. In silico investigations included drug-likeness and ADMET predictions, as well as molecular docking on catalase (PDB: 2CAG) and fungal CYP51 (PDB: 1EA1). AMZ exhibited dose-dependent radical scavenging in the DPPH assay, reaching 76.88 ± 3.20% inhibition at 1000 µg/mL, with an EC₅₀ of 26.03 ± 0.21 µg/mL, close to that of BHT (23.65 ± 0.22 µg/mL). In the FRAP assay, AMZ showed a higher reducing power than BHT at a low concentration (OD₅₀ µg/mL 0.177 ± 0.023 vs. 0.134 ± 0.017), although its FRAP EC₅₀ was higher (700.48 ± 22.54 vs. 400.16 ± 8.67 µg/mL). AMZ displayed broad-spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria and fungi, with particularly strong effects on Bacillus subtilis (44.5 ± 0.5 mm; MIC/MBC 0.008 mg/mL) and Aspergillus niger (30 mm; MIC/MBC 0.030 mg/mL), in some cases comparable or superior to streptomycin and fluconazole. In silico analysis indicated that AMZ fulfilled major drug-likeness rules, showed high predicted intestinal absorption (91.14%), and was classified as non-AMES toxic, while docking predicted favorable binding to catalase and CYP51, in agreement with the experimental antioxidant and antifungal activities. These findings highlight the potential of AMZ as a multi-target pyridine-based lead compound that warrants further structural optimization and in vivo evaluation for applications in oxidative-stress-related and infectious conditions. Full article

To efficiently remove oxytetracycline (OTC) pollution from water bodies, this study utilized fava bean straw as a precursor to synthesize iron-nitrogen (Fe/N) co-doped biochar via pyrolysis. By regulating the synthesis ratio of iron and nitrogen, the material’s adsorption performance was optimized. The adsorption characteristics and mechanisms of OTC were systematically investigated. The findings reveal that when the proportion of iron to nitrogen is set at 1:3, the adsorption efficacy reaches its peak. Moreover, this material demonstrates outstanding reusability characteristics. The outcomes of kinetic fitting suggest that the adsorption procedure adheres to the pseudo-second-order kinetic model (R² = 0.967), primarily characterized by chemisorption. The isothermal adsorption data better fit the Langmuir model (R² = 0.9984), with a theoretically attainable upper-limit adsorption capacity reaching 666.13 mg/g. This signifies the occurrence of monolayer adsorption, while the adsorption procedure constitutes an endothermic reaction. Based on characterization and mechanistic analysis, it can be concluded that the adsorption mechanism of Fe1N3KBC on OTC mainly involves π-π stacking interactions and chelation reactions. The Fe/N co-doped biochar prepared in this present research features readily available raw materials and a simple preparation process, combining high adsorption efficiency with excellent stability. It provides a novel technical paradigm for developing environmentally friendly adsorbents to address antibiotic pollution in water bodies. Full article

The urgent need to mitigate carbon dioxide (CO₂) emissions from fossil-fuel-based electricity generation has driven research into advanced materials for post-combustion carbon capture. This paper presents a modified solvothermal technique to synthesize zinc (Zn) and magnesium (Mg) based MOF-74 suitable for CO₂ capture from coal-fired power plants. The materials were synthesized through a solvothermal method using N,N-dimethylformamide (DMF) as the primary solvent, and subsequently characterized using Brunauer–Emmett–Teller (BET) surface area analysis, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), and thermogravimetric analysis (TGA). Both MOFs contained oxygen-containing functional groups and were thermally stable up to 430 °C and 600 °C respectively, making them ideal for carbon capture. The low-pressure N₂-BET surface areas were 55 m²/g and 24.73 m²/g. In conclusion, the Zn material had a mesoporous structure, making it more favorable for carbon capture. It was found that prolonged synthesis time weakened the MOF structure. Future work should experimentally evaluate CO₂ capture from coal-derived flue gas using Zn/Mg-MOF-74 materials, investigating adsorption behavior and kinetics through isotherm and kinetic models, while also assessing the effect of varying Zn: Mg ratios under optimized synthesis conditions. Full article

The development of bio-based functional materials through the upcycling of agri-food residues represents a sustainable strategy to reduce environmental impact and promote circular economy. This study achieved valorization by combining two tomato by-products: peels exhausted after supercritical fluid extraction and harvest residues mainly composed of stems and field wastes. Polyphenol-rich extract (TPPf) was obtained from peels through ultrasound-assisted maceration and solid-phase extraction, while cellulose from tomato harvest residues (THRs) was converted into carboxymethyl cellulose (THR-CMC, degree of substitution 0.76), as confirmed by structural analyses. Functional bioplastic films were prepared by solvent casting THR-CMC, plasticized with glycerol, and enriched with different TPPf concentrations (0–100 mg/100 mL). Increasing TPPf content enhanced mechanical strength and UV-blocking efficiency, while moderate loading improved moisture barrier properties. The films exhibited notable antioxidant activity (ABTS, DPPH assays) and biodegradability, demonstrating biofunctional performance suitable for food packaging. This integrated valorization strategy highlights the potential of combining agricultural and industrial tomato residues to develop sustainable, biodegradable, and active packaging materials, supporting waste reduction and circular bioeconomy objectives. Full article

Aquifers are increasingly threatened by the uncontrolled release of non-biodegradable chemicals derived from anthropogenic activities. The development of new remediation strategies has therefore focused on the use of sustainable adsorbent materials, including synthetic organic hydrogels and biochars produced from agricultural residues. In this study, the removal of two organic pollutants, the herbicide Metribuzin (MEB) and Propyl Paraben (PrP), from aqueous environments was investigated using negatively charged hydrogels and biochars derived from lime peel, respectively. Propyl Paraben (PrP) and Metribuzin (MEB) are among the pollutants frequently found in aquatic environments, and the effective and sustainable removal approaches remain under investigation. The hydrogels studied (P(DMAM co-ANax)) were based on sodium methacrylate (ANa) copolymerized with N,N-dimethylacrylamide (DMAM). The adsorption performance of the materials was evaluated through UV-Visible absorption spectrophotometry and High-Performance Liquid Chromatography (HPLC). The results of this study showed that the hydrogel achieved a very high removal efficiency for MEB, which was over 80% for the concentration range studied (max $Q_e$ = 0.386 mg/g). Similar behavior was also recorded for the biochar from lime peel, which achieved almost complete removal of PrP (~100%) at the lowest concentrations of the contaminant (5 mg/L) and maintained high removal rates (78%) at 10 mg/L (max $Q_e$ = 0.187 mg/g). These results demonstrate the potential of both types of materials to efficiently remove the studied contaminants from water, indicating their suitability for environmental remediation applications. This work contributes to the development of cost-effective and eco-friendly adsorbents for the treatment of water pollution caused by emerging organic compounds. Full article

Bacteriophages (phages) offer a targeted biocontrol solution, but their direct application is hampered by environmental instability. To address this, we developed a novel, food-grade microcapsule system for phage delivery using layer-by-layer (LbL) self-assembly of zein and carboxymethyl chitosan (CMCS). Lytic phages targeting specific spoilage bacteria were successfully encapsulated via electrostatic interactions. Characterization confirmed the formation of a multilayer structure, driven primarily by hydrogen bonding and electrostatic forces between the wall materials. The microencapsulation markedly enhanced phage stability against thermal (60 °C and 70 °C) and extreme pH (2.0, 12.0) stresses and provided a controlled release profile in a simulated fish exudate. When applied to fresh-cut sea bass (Lateolabrax japonicus), the phage-loaded microcapsules (CMCS3), constructed via a three-layer zein/CMCS LbL assembly, significantly delayed the pH rise during refrigerated storage, maintaining a final pH of 6.28 compared to 7.28 in the control group after 5 days. The microcapsules also effectively suppressed microbial growth (total viable count (TVC) was maintained below 6 log CFU/g) and controlled lipid oxidation (thiobarbituric acid reactive substances (TBARS) values were kept at 0.62 mg malondialdehyde/kg) while better preserving texture and color stability compared to free phages. This zein/CMCS-based LbL system presents a promising strategy for advancing phage-based biopreservation in aquatic products through enhanced physical protection, sustained release, and improved stress tolerance. Full article

Enrofloxacin (ENR), as a widely used antimicrobial agent in aquaculture, poses potential risks to ecosystems and human health due to its environmental persistence. Therefore, it is of great significance to explore efficient methods for removing ENR from aquaculture wastewater. In this study, a series of shrimp shell-derived aerogel (MBC300–MBC700) were fabricated from Litopenaeus vannamei shells through chemical modification followed by pyrolysis at 300–700 °C, and their adsorption performance and mechanisms toward ENR were systematically investigated. The modified porous materials exhibited a well-developed micro–mesoporous structure, high specific surface area, and abundant surface functional groups. Meanwhile, MBC400 demonstrated the highest adsorption capacity for ENR, reaching 14.56 mg/g, with a corresponding specific surface area of 77.71 m²/g. The adsorption kinetics followed the pseudo-second-order model, and the isothermal data were better fitted by the Freundlich model, indicating a chemisorption-dominated, heterogeneous multilayer adsorption process. Thermodynamic analysis revealed that the adsorption was spontaneous (ΔG < 0) and endothermic (ΔH > 0). In regeneration experiments, 30% ethanol solution achieved the best desorption efficiency for MBC400, with adsorption efficiency remaining above 75% after three cycles. Based on the characterization and adsorption results, adsorption mechanism of ENR on MBC400 was elucidated as a synergistic effect of hydrogen bonding, π–π stacking, electrostatic interaction, and surface complexation. This study provides a novel strategy and theoretical basis for the high-value utilization of shrimp shell waste and for the efficient removal of fluoroquinolone antibiotics from aquaculture effluents. Full article