Hydrogel patches based on alginate and gelatin were fabricated in four formulations (PS0, PS1, PS0C, PS1C) to elucidate how morphology, thermal stability, optical response, and swelling behaviour jointly determine their suitability as drug-release platforms. A comprehensive multi-technique characterization was performed, integrating atomic force microscopy (AFM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), optical reflectance/transmittance spectroscopy, profilometry, and swelling kinetics. AFM revealed that non-crosslinked samples (PS0, PS1) exhibit smooth but mechanically fragile surfaces, whereas calcium crosslinking (PS0C, PS1C) induces a marked increase in nanoscale heterogeneity and load-bearing microdomains. Thermal analyses (TGA/DSC) confirmed the structural reinforcement of crosslinked networks, showing higher transition temperatures, reduced mass-loss rates, and increased residual mass fractions. Optical measurements demonstrated that crosslinking and dye loading modulate internal scattering and absorption, reflecting changes in microstructural organization. Swelling experiments further highlighted the dominant role of ionic crosslinking in controlling water uptake, with PS0 and PS1 undergoing rapid destabilization, while PS0C and PS1C maintain structural integrity and exhibit slower, diffusion-limited hydration. Taken together, these results show that the combined morphological, thermal, optical, and swelling signatures provide a coherent physical basis for modelling internal diffusivity in Alg/Gel hydrogels. The observed structure–property relationships establish the mechanistic foundation required to predict and optimize drug release from these patches in realistic application scenarios.
In this study, strontium ferrite (SrFe12O19)/polyetheretherketone (PEEK) composites were fabricated by hot-press molding and systematically exposed to acidic (HCl, H2SO4), alkaline (NaOH), and neutral (NaCl solution, salt spray) corrosive media. Multi-scale characterization including scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and vector network analysis revealed distinct attack pathways: alkaline medium caused severe surface erosion and interfacial degradation of the PEEK matrix; acidic medium induced local surface erosion and microcrack propagation; neutral salt medium mainly introduced physical interfacial perturbations. These microstructural evolutions directly regulated the electromagnetic parameters and critically altered the balance between impedance matching and attenuation constant. Contrary to conventional assumptions, the H2SO4-corroded sample exhibited the best overall absorption performance (RLmin = −37.8 dB, EAB = 3.15 GHz) at a thickness of 10 mm, due to a moderate decrease in permittivity, retention of magnetic loss, and significantly improved impedance matching. In contrast, the NaOH-treated sample showed the worst absorbing performance (RLmin = −38.4 dB but EAB = 0.2 GHz) due to severe impedance mismatch. This study establishes a corrosion-type-dependent "structure–property" linkage, providing a theoretical basis for designing highly stable microwave absorbers for complex service environments.
We present a binary CuO/TiO2 nanocomposite synthesized via a facile hydrothermal method, along with its pristine CuO and TiO2 counterparts, for high-performance supercapacitor applications. The powder X-ray diffraction (PXRD) analysis revealed that the CuO/TiO2 compound has embraced the monoclinic and anatase phase structures. Owing to the combination of nano-flower and nano-spherical architecture, the CuO/TiO2 shows exceptional surface characteristics to provide more reaction centers and shorten the ion transport path. The zeta potentials of the investigated materials ranged from - 4.2 mV (CuO) to - 42 mV (CuO/TiO2), with TiO2 at an intermediate value of - 27 mV, highlighting their diverse surface charge properties. Notably, binary CuO/TiO2's highly negative zeta potential of - 42 mV indicates strong electrostatic repulsion, ensuring excellent colloidal stability and inhibiting aggregation. To determine the optimal electrolyte, data on electrochemical performance were recorded for four electrolytes (KOH, NaOH, Na2SO4 and Na2CO3) at fixed (2 M) concentrations for bare CuO, TiO2 and binary CuO/TiO2 composite in a three-electrode set-up. These findings demonstrate that the CuO/TiO2 nanocomposite exhibits the best capacitive behavior in a variety of electrolytes. In particular, the Na2CO3 aqueous electrolyte exhibits the highest electrochemical capacitance of 417 F g-1 at 1 A g-1 with its long-life span regarding cycling stability of 94 % after 5000 cycles for CuO/TiO2. This is due to the shortest relaxation time, and nearly ideal polarizability. An asymmetric supercapacitor (CuO/TiO2‖AC) assembled in the optimized Na2CO3 electrolyte exhibited a specific capacitance of 104.2 F g-1, an energy density of 9.26 Wh kg-1, a power density of 0.18 kW kg-1, and excellent cycling stability with 93 % capacitance retention after 5000 cycles. Our findings provide a unique perspective on the combination of ionic electrolytes with CuO/TiO2 material and suggest that the charging process can be regulated to yield significant improvements in electrochemical kinetics.
Graphene oxide (GO) is considered an effective modifier in cementitious materials. However, whether GO-induced structural changes in calcium silicate hydrate (C-S-H) can be retained and translated into pore refinement and micromechanical enhancement during pressure-driven densification remains insufficiently understood. In this study, two complementary experimental series were conducted, involving the co-precipitation synthesis of GO-modified C-S-H and the mechanical compaction of pure and GO-containing C-S-H. By integrating structural characterization with controlled compaction and micromechanical testing, this study examines the relationship among GO-induced silicate-chain regulation, particle assembly, pore refinement, and the local mechanical response of compacted C-S-H. The results show that GO promoted silicate chain polymerization and layered growth of C-S-H. In the compacted system, compared with pure C-S-H, the elastic modulus of the C-S-H/GO sample increases from 13.36 to 26.34 GPa (≈97%), and the hardness increases from 0.27 to 0.65 GPa (≈141%). GO also enhanced pore refinement and water stability by Ca2+-mediated interfacial densification. These results indicate that GO-induced structural regulation contributes to improved micromechanical performance and reduced water-induced softening in densified C-S-H, providing experimental support for understanding its multiscale reinforcement mechanism under mechanically densified conditions.
This article presents a comprehensive analysis of additive-induced property enhancement in polymer composites processed via additive manufacturing. The incorporation of ceramic, carbon-based, and metallic fillers has been shown to significantly improve mechanical strength, thermal stability, electrical conductivity, and functional responsiveness, enabling the transition of 3D printing technologies toward load-bearing and multifunctional applications. Ceramic reinforcements such as zirconia and silicon carbide improve heat resistance and wear performance, whereas carbon fibres, graphene, and MWCNTs enhance stress transfer efficiency, stiffness, and fracture toughness. Metallic additives, including iron, copper, and stainless steel, enhance conductivity and mechanical robustness. Additives are systematically classified into reinforcing fillers, functional additives, and processing modifiers, each influencing rheology, interfacial adhesion, and print fidelity. Nanoscale additives further enable advanced properties, such as self-healing, shape-memory behaviour, and electromechanical responsiveness. Despite these advantages, challenges such as agglomeration, poor matrix–filler compatibility, high material costs, and degradation under service conditions remain unresolved. Emerging research directions include bio-based fillers, AI-driven process optimisation, and synergistic hybrid reinforcement systems. This review provides critical insights for optimising material design strategies in high-performance additive manufacturing. The distinctive contribution of this review is the integration of nanoscale interfacial interactions, microscale filler dispersion, mesoscale print-induced architecture, and macroscale mechanical response into a unified process–structure–property framework for additive-manufactured polymer composites.
Chromium-coated zirconium alloy cladding is a promising accident-tolerant fuel concept because a continuous Cr2O3 scale can suppress rapid zirconium oxidation during high-temperature steam exposure. A MATLAB-based area-weighted model was developed to estimate apparent oxide growth for defect-containing Cr-coated zirconium alloy cladding at 1200 °C and 1300 °C. The model combines temperature-dependent parabolic ZrO2 growth at exposed defect sites with a parabolic Cr2O3 early-stage branch at intact coating regions. An oxide-thickness-based remaining-Cr proxy is used only as a calibration-anchored screening indicator of protection loss; no quantitative validation for prescribed defect fractions is claimed. In this trial, the 18 μm coating proxy time changes from 2.50 h at 1200 °C to 0.68 h at 1300 °C. The results emphasize that coating continuity and initial Cr thickness are important for preserving accident-tolerant performance under LOCA-relevant conditions.
