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In this paper, the intrinsic structure model of SiCp/Al composites was constructed based on the analysis of static and dynamic mechanical properties of SiCp/Al composites. Quasi-static tensile tests were conducted for SiCp/2a14Al composites with 20% volume fraction using an electronic universal testing machine to study the static mechanical properties of the material. Dynamic compression tests were conducted at different temperatures (20 °C-400 °C) and strain rates (500 /s-3000 /s) using a Hopkinson compression bar test to analyze the dynamic mechanical properties of the material. The Johnson-Cook (JC) intrinsic structure model of SiCp/Al composites was constructed based on the material stress-strain test data under static and dynamic conditions, and the model was optimized by genetic algorithm. The results show that the SiCp/Al composites exhibit a strain-reinforcement effect under quasi-static conditions; under dynamic loading conditions, the material flow stress increases with the strain rate and exhibits a strain-rate reinforcement effect, which is related to the volume fraction of silicon carbide particles. With the increase of temperature, the flow stress decreases and exhibits a temperature-softening effect. The average error between the least squares fitted JC model and the experimental values is large, and the model error is reduced after optimization by genetic algorithm, which can accurately predict the rheological behavior of SiCp/2a14Al composites. [ABSTRACT FROM AUTHOR]

In this paper, silver nanoparticles/sulfonated polystyrene (Ag/SPS) composite microspheres were synthesized by using sulfonated polystyrene microspheres (SPS) as carriers and loaded with silver nanoparticles on its surface. The composite microspheres were characterized by scanning electron microscopy, infrared spectroscopy, XRD spectroscopy and thermogravimetry. The results showed that at 70 °C and reaction time of 8 h, the monodispersity of Ag/SPS composite microspheres prepared by chemical reduction method was good and the silver nanoparticles were uniformly coated. The results of catalytic reduction of methylene blue showed that in a certain range, the higher the silver content of the composite microspheres, the faster the catalytic rate. The results of reuse experiments showed that the composite microspheres had high reusability. [ABSTRACT FROM AUTHOR]