In this work, different flexible PVC composites doped with WO3, red clay and brine sludge were fabricated for gamma-ray shielding applications. The radiation shielding properties of these composites were determined experimentally at different energies (0.059, 0.662, 1.173, and 1.332 MeV). The experimental data were compared with theoretical Phy-x values, where the observed deviation between them didn’t exceed 5
This study investigates temperature-dependent hydration mechanisms of superabsorbent polymer (SAP)-modified cement paste. SAP dynamically regulates cement hydration via reversible, temperature-sensitive water absorption and release. At 40°C, the hydration induction period vanishes; hydration rate rises over 50
In fracture mechanics, material failure can occur when the applied load is directly proportional to the maximum stress region or stress concentration point. In this study, a finite element analysis was conducted to investigate the reduction of stress concentration factors in aluminum plates with a central hole using various repair strategies. The repair configurations included single- and double-sided bonded composite patches, piezoelectric actuators with varying electric fields, and hybrid systems combining both techniques. The analysis was performed under uniaxial tensile loading to evaluate the performance of each method. A detailed parametric study of the bonded repair system was conducted, and the stress distribution in the optimized repair configuration was evaluated. Results showed that the double-sided composite patch reduced the SCF by approximately 55.67
Many Liquid membranes were evaluated for the selective extraction of cesium cation. Nevertheless, their chemical instability over time and the low flux diffusion present major drawbacks for their use in practical industrial applications. In this study, we introduce a solid membrane (PAN/Sty-Met(Py-Tet)) that uses a tetrapodal tetrazole-pyrazole conjugate molecule as transporter. This solid membrane was created by photopolymerizing a formulation of tetrazole-pyrazole conjugate monomer on a polyacrylonitrile support, resulting in an asymmetric and amorphous structure. TGA analysis reveals that the solid membrane (PAN/Sty-Met(Py-Tet)) possesses a thermal stability until 330 °C. The transport results show that the resulting membrane transports Cu2+ over Zn2+, Pb2+, Co2+, and Cd2+ cations in the competitive conditions. the Cu2+ flux achieved 34.5 × 10− 3 mol/h×m2 at room temperature under neutral pH. Its performances were also found stable over 8 cycles. The present membrane could be considered as potential candidate for the selective isolation of the Cu2+ in aqueous media at room temperature.
Developing sustainable lightweight materials using marine waste-derived reinforcements offers a promising pathway to resource-efficient manufacturing. This study investigates fabricating AZ91D magnesium hybrid composites reinforced with fish bone ash and seashell ash, along with graphite, zinc, silicon carbide, and boron carbide, using a stir-casting approach. Incorporating bio-waste-derived reinforcements aims to enhance the functional performance of magnesium alloys while promoting waste valorization and reducing dependence on conventional reinforcement materials. The fabricated hybrid composites were systematically evaluated for microstructural characteristics, mechanical behaviour, corrosion response, and machining performance. The machining behaviour was further optimized using a hybrid decision-making framework integrating Response Surface Methodology (RSM), Spherical Fuzzy Analytic Hierarchy Process (SF-AHP), and Fuzzy Measurement Alternatives and Ranking according to Compromise Solution (Fuzzy MARCOS). The study analyzed the effects of key ultrasonic-assisted turning parameters, including cutting speed, feed rate, and ultrasonic power, on surface roughness, material removal rate, energy consumption, and tool wear. The results show that incorporating marine waste-derived reinforcements and ceramic phases improves the structural integrity, wear resistance, and corrosion performance of the AZ91D matrix. Furthermore, the hybrid optimization methodology effectively identifies suitable machining conditions by balancing multiple conflicting performance responses. The proposed sustainable composite development strategy provides an integrated approach for converting marine waste into value-added engineering materials while improving machining efficiency. This work advances environmentally responsible magnesium-based hybrid composites for potential lightweight structural and advanced manufacturing applications.
