Advancing multifunctional materials for environmental and technological applications requires the design of systems that combine structural stability with enhanced optical, photocatalytic, and dielectric properties. In this context, phosphate-based glasses and glass-ceramics within the ZnO–Na₂O–P₂O₅–TiO₂ system were investigated, with particular emphasis on the role of TiO₂ incorporation. Controlled thermal treatments were employed to induce partial devitrification, yielding crystalline phases finely dispersed within a residual glassy matrix. Structural and microstructural characterizations confirmed the amorphous nature of the as-prepared samples and their progressive crystallization upon heating, highlighting the contribution of Ti–O–P linkages to network reinforcement.

Optical analyses demonstrated a noticeable enhancement in UV absorption and a red shift of the absorption edge with increasing TiO₂ content, coupled with a slight narrowing of the optical band gap. These modifications indicate improved light-harvesting efficiency, which is beneficial for photocatalytic applications. Photocatalytic activity was evaluated through the degradation of methylene blue under UV–visible irradiation. All studied compositions exhibited photocatalytic effects, with higher TiO₂ concentrations accelerating the degradation process, thus confirming the catalytic role of titanium.

Dielectric investigations revealed frequency-dependent permittivity, with significant improvements observed upon TiO₂ addition. The reduction of polarization losses and stabilization of dielectric behavior further emphasized the potential of these materials for electronic and energy-related uses.

Overall, these results demonstrate that TiO₂-doped phosphate glasses and glass-ceramics successfully integrate optical, photocatalytic, and dielectric functionalities, making them promising candidates for advanced applications in environmental remediation and dielectric technologies.

Corrosion is a life-threatening industrial problem that causes significant economic losses, safety concerns, and, more importantly, issues in various industrial sectors like construction, chemical processing, and marine engineering. Our research focuses on the production of anticorrosive nanocomposite coatings based on epoxy resin reinforced with graphene oxide (GO) nanoparticles and chitosan nanoparticles (CNPs) to provide protection against corrosion. Epoxy resin was chosen as a primary matrix due to its superior mechanical properties and resistance to chemicals. Graphene oxide (GO) and Chitosan (CH NPs) were selected as nanofillers. Chitosan was chosen based on its biocompatibility and adhesive features, whereas Graphene oxide (GO) was chosen as a barrier enhancer. In this work, GO was prepared through the Modified Hummers’ method, and CH NPs through Green Synthesis techniques. The CH/GO nanocomposite was prepared with varying concentrations of GO (0.5% and 1%) by the in situ method. These composites were incorporated into Epoxy Resin at 2wt% and then drop-cast onto substrate sheets. Different characterization methods have been used to determine the structure, morphology, and anticorrosive performance of the hybrid coatings: Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Electrochemical Impedance Spectroscopy (EIS). Analysis revealed that the 1 % GO-CH NPs coating had the highest corrosion resistance with a very high value of impedance, poor porosity, and much better surface morphology when compared to the control.

Trimesic acid–nickel-based metal–organic frameworks (Ni-MOFs) have attracted growing attention since their first synthesis by Yaghi and co-workers in 1996, owing to their potential applications in a wide range of fields, including CO₂ hydrogenation, photocatalysis, batteries, and supercapacitors. Furthermore, Ni-based MOFs are known to undergo structural transformations even under relatively mild conditions, rendering their investigation particularly compelling. In this study, we examine the influence of different co-solvents on the solvothermal synthesis of Ni-BTC. While N,N-dimethylformamide (DMF) is commonly employed as the primary solvent in MOF synthesis, here, it is combined with water and formic acid as co-solvents in order to evaluate their impact on framework formation.

The Ni-BTC samples were synthesized via a straightforward and reliable solvothermal method. Following the mixing of the precursors with the solvent system (DMF, DMF/water, or DMF/formic acid), the resulting solution was heated at 120 °C for 12 h and subsequently washed. The recovered solids were then activated under vacuum at 110 °C overnight. The obtained materials were thoroughly characterized by XRD, N₂ adsorption/desorption isotherm, FTIR, UV-Vis, TGA and SEM analysis.

Each solvent formulation produced crystalline structures with distinctive features and well-defined morphologies. When DMF was employed as the sole solvent, the resulting material exhibited a crystalline structure consisting of hexagonal crystals with a stacked 2-D layer, represented by the simplified formula Ni(HBTC)(DMF)₂·xDMF. The incorporation of water as a co-solvent significantly altered the crystallization pathway, leading to the formation of the well-known Ni₃(BTC)₂·12H₂O phase with acicular crystals. In contrast, the presence of formic acid promotes competitive coordination with the metal centers, leading to the formation of alternative architectures with an enhanced surface area. Structural transitions are observed when the material is brought into contact with water, whereas exposure to ambient humidity results in a macroscopic color change.

Natural Deep Eutectic Solvents (NADESs) are formed through hydrogen bonding interactions between a hydrogen bond acceptor (HBA) and a hydrogen bond donor (HBD), resulting in a stable, homogeneous liquid. In this work, preliminary analyses were conducted to evaluate the influence of the synthesis method on the physicochemical properties of NADESs. Two preparation techniques, mechanical agitation and ultrasound, were applied to four NADES systems composed of choline chloride (ChCl), urea (Ur), citric acid (CA), and glycerol (Gly): N1 (CA: Gly, 1:3 M), N2 (ChCl: Ur, 2:1 M), N3 (ChCl: CA, 1:1 M), and N4 (ChCl: Gly, 1:1 M), all with 20% (w/w) water. Properties assessed included pH, electrical conductivity, density, and refractive index. Results showed variable pH values without a consistent trend. Electrical conductivity was higher in NADESs synthesized via agitation, notably in N2 (37.7 mS/cm vs. 16.4 mS/cm with ultrasound), suggesting enhanced ionic mobility. Ultrasound-assisted synthesis generally yielded NADESs with greater density, as observed in N1 and N4 (1.155 vs. 1.084 g/cm³ and 1.154 vs. 1.138 g/cm³, respectively), potentially due to improved molecular packing. Refractive index values remained relatively stable across methods, though slight deviations were observed. These findings indicate that mechanical agitation favors higher conductivity, whereas ultrasound may promote greater homogeneity and compactness. Therefore, the choice of synthesis method should be tailored to the targeted physicochemical profile for specific applications.

This study investigated the use of Representative Volume Elements (RVEs) to understand stress distribution in magnetoelectric composites. These composites, which combine piezoelectric and magnetostrictive phases, were shown to have performance strongly influenced by stress development at the microscale. Given the inherent heterogeneity of real materials, the RVE approach provided a means to capture microscale behavior and translate it into effective macroscale properties. Two scenarios were modeled to examine the effect of inclusion arrangement: one with ordered inclusions placed at regular intervals, and another with randomly distributed inclusions, representing more realistic microstructures. Boundary conditions for the RVE simulations were derived from a preliminary test model, where average strain values under thermal loading were calculated and then imposed on the RVE boundaries.The findings indicated that ordered inclusions promoted more uniform stress distributions, reducing concentration zones and resulting in a predictable material response. In contrast, random inclusions produced localized stress peaks and irregular patterns, demonstrating how microstructural disorder amplified stress heterogeneity. The study highlighted the importance of microstructural arrangement in influencing the mechanical response of magnetoelectric composites. By linking domain-level interactions with continuum-level performance, the RVE framework provided a robust tool for predicting stress evolution. This approach offered valuable insights into stress mechanisms at inclusion boundaries and suggested pathways for optimizing composite design for advanced sensing, actuation, and multifunctional applications.

Background
The mechanical characterization of fiber-reinforced composites is crucial for advancing materials engineering but traditionally relies on destructive, time-consuming testing protocols. The emergence of deep learning provides opportunities for non-destructive, image-based evaluation methods that can accelerate material design and performance assessment.

Methods
This study proposes a novel image-driven framework that integrates a YOLOv8n-based object detection model with a Convolutional Neural Network (CNN) to predict tensile behavior in 3D-printed fiber-reinforced nylon composites from scanning electron microscopy (SEM) images. The YOLOv8n model was used to identify and quantify deformation regions before and after tensile testing, while the CNN predicted deformation rates directly from raw image features. By combining these outputs, the framework computes deformation change, maximum deformation rate, and ultimate tensile load. Model interpretability was further enhanced using Gradient-weighted Class Activation Mapping (Grad-CAM).

Results
The predictive framework was validated against 50 load–displacement curves representing the full spectrum of experimentally observed behaviors in 3D-printed nylon fiber composites. The YOLOv8n model achieved an accuracy of 0.937, while the CNN reached an accuracy of 0.961 in predicting deformation rates. Image-based predictions demonstrated excellent agreement with experimental measurements (R² = 0.9995, Pearson r = 0.9998). Furthermore, ultimate tensile loads derived from model outputs enabled the virtual reconstruction of load–displacement responses, effectively bridging microstructural imaging with macroscopic mechanical performance.

Conclusion
The proposed framework establishes a scalable, non-destructive approach for predicting tensile behavior in fiber-reinforced composites. By integrating high-resolution SEM analysis with deep learning models, this methodology provides a reliable pathway for virtual material testing, reducing experimental demands and accelerating the evaluation and design of advanced composite systems.

BiFeO₃ (BFO) is a widely studied room-temperature multiferroic; however, phase instability, leakage, and weak ferromagnetism have motivated the adoption of strategies such as doping and entropy engineering to enhance its performance. Building on our earlier report of the high-entropy oxide Bi₀.₅La₀.₁In₀.₁Y₀.₁Nd₀.₁Gd₀.₁FeO₃, which exhibited room-temperature ferromagnetism and excellent dielectric performance, we now investigate configurational entropy effects on the A site via multi-principal rare earth (RE) substitution to stabilize the perovskite phase and improve functional response. Bi_0.9(RE)_0.1FeO₃ (RE = La, Nd, Gd, Eu, Y; 2% each) was prepared by a conventional solid-state route and pre-calcined at 600 °C, followed by sintering at 950 and 1000 °C. Phase purity and microstructure were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Room-temperature magnetic behavior was evaluated using vibrating sample magnetometry (VSM), and dielectric response (ε′, tan δ), together with AC conductivity (σ), was measured at 1 kHz. XRD spectra confirmed perovskite formation at both temperatures, with sharper peaks at 1000 °C indicating higher crystallinity and minor secondary peaks, while SEM showed denser and more uniform grains. Magnetic measurements revealed weak ferromagnetism with coercivity in the range of 80–120 Oe, consistent with partial disruption of the spin cycloid. Dielectric response was also increased from ~960 (950 °C) to ~1500 at 1000 °C, while tan δ decreased from 0.77 to 0.69 at 1 kHz. Moreover, a slight rise in AC conductivity at 1000 °C (from 4.05×10⁻⁵ to 5.08×10⁻⁵ S cm⁻¹) was attributed to oxygen vacancy formation driven by Bi volatility, Fe²⁺/Fe³⁺ hopping, and reduced grain boundary resistance due to more continuous grain networks. These results indicate that configurational entropy, together with careful control of thermal processing, can be used to stabilize BiFeO₃ and improve its multifunctional properties.

Synthesis and characterization of alginic acid scaffolds with possible tissue regeneration applications

Hydrogels are 3D networks of hydrophilic crosslinked polymers that are obtained from synthetic or natural sources. Previous works have described these materials as having high water retention capacity, biodegradability and biocompatibility. These characteristics allow hydrogels to be used as scaffolds for tissue regeneration.

In this work, three series of alginic acid hydrogels were synthesized using different chemical crosslinker agents, piperazine, spermidine and 1,4-diaminobutane, with concentrations varying between 5 wt.% and 100 wt.%. The syntheses were carried out in a temperature range of 22≤T/ºC≤ 27 and a constant stirring speed. Gels were characterized using scanning electron microscopy (SEM). According to Matos et al (2021) and Ştefan Ţălu’s (2022), it is widely known that SEM analysis provides a relevant morphological map of the surface area, texture and pore size of hydrogels. Another test included infrared spectroscopy (FT-IR), mass spectrometry and rheological analysis (viscosity η), as well as biocompatibility tests with fibroblast cultures at 37 ^oC. All experimental sets were performed in triplicate.

According to the results, SEM analysis revealed that 1, 4- diaminobutane gels have a pore size of 1 µm to 3 µm, while spermidine and piperazine exhibit values from 1µm to 13 µm and 1µm to 14 µm, respectively. The pore size range is determined by the molecular structure of the crosslinker agent. This means that spermidine and piperazine gels result in wider pores than 1,4- diaminobutane hydrogels. On the other hand, tests showed that cells did not adhere to the surface of the gels. However, the formulation of each materials has been modified for better adhesion viability. All hydrogels absorb large amounts of solvent in aqueous conditions. However, in saline solutions, piperazine gels dissolve, while 1,4- diaminobutane and spermidine hydrogels tend to fragment. The results obtained suggest that alginic acid hydrogels have a high viability to be applied for tissue regeneration treatments.

Microplastic (MP) pollution has become a global concern due to its environmental impacts and risks to human health. Recent studies have confirmed the ubiquitous presence of MPs in aquatic ecosystems, groundwater, freshwater bodies, and even in food and human organisms.

This study evaluated MP removal in full-cycle Water Treatment Plants (WTPs), which operate through coagulation, flocculation, sedimentation, filtration, and disinfection. Samples of 2 L of raw water and 2 L of treated water were collected in glass bottles from two WTPs in Goiânia, Brazil (Meia Ponte and Mauro Borges) over three consecutive days, considering the 4-hour hydraulic detention time from influent to effluent. The samples were filtered using 5 µm membranes (microplastics) and 0.5 µm membranes (nanoplastics) with a vacuum pump, Büchner funnel, and Kitasato flask. Particle identification was performed by optical scanning with a Stemi 508 Zeiss stereomicroscope.

The results revealed the persistence of MPs in both raw and treated water. The Meia Ponte WTP presented higher particle concentrations compared to the Mauro Borges WTP, possibly due to differences in their watershed characteristics. The detection of MPs in treated water highlights the limitations of conventional full-cycle treatment and raises concerns about continuous human exposure.

These findings emphasize the urgent need to improve removal technologies and advance research to identify the composition and morphology of MPs. Alternative strategies, such as slow sand filtration, appear promising to mitigate contamination and ensure safer drinking water.

M-type hexaferrites are one of the most important magnetic materials due to their applications as permanent magnets, magnetic recording media, microwave components and devices, etc. We report a study on the correlation between the synthesis procedure on the microstructure and the magnetic properties of BaFe₁₂O₁₉ nanopowders. These were synthesized by two modified co-precipitation methods: microemulsion co-precipitation and sonochemical co-precipitation (sonochemistry). We used a water-in-oil reverse microemulsion system with CTAB (24 wt.%) as a cationic surfactant, n-butanol (16 wt.%) as a co-surfactant, n-hexanol (20 wt.%) as a continuous oil phase, and an aqueous solution of metallic ions (40 wt.%) for the microemulsion method. In the case of sonochemical co-precipitation, high-power ultrasound stirring was applied during the co-precipitation process. The obtained precursors were subjected to high-temperature synthesis. The BaFe₁₂O₁₉ powders consisted of particles exhibiting an irregular shape between a sphere and a hexagonal platelet, as the process of formation of the platelet shape typical of the BaFe₁₂O₁₉ hexagonal structure was interrupted due to the small particle size. The average particle size of BaFe₁₂O₁₉ nanopowders is 140 nm and 86 nm for microemulsion and sonochemistry, respectively. The magnetic hysteresis loops were measured at room temperature in an applied magnetic field of 30 kOe. The sample obtained by microemulsion had a high coercivity value of 4 kOe, while the powder obtained by sonochemical co-precipitation was 140 Oe. The BaFe₁₂O₁₉ powders consisted of particles with a size below 150 nm and exhibited an irregular shape between a sphere and a hexagonal platelet, as the process of formation of the platelet shape typical of the BaFe₁₂O₁₉ hexagonal structure was interrupted due to the small particle size.