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Heterostructured V 2 O 5 /In 2 O 3 core-shell nanorods were prepared by the combination of solid solution and hydrothermal methods. Microstructural and spectroscopic studies reveal the effective core-shell hetero-nanostructure. The gas sensor based on these nanorods exhibits remarkable gas sensing properties in both static and dynamic modes. It presents optimum working temperature of 190 o C, a reasonable response speed and high selectivity with an ultra-stable reproducible response towards n-propylamine. The sensor also shows enhanced optimum sensitivity (~14), which is 3.90 times as compared to the pure V 2 O 5 nanorods. Such promising gas sensing behavior of the hetero-nanostructured core-shell nanorods has been explained on the basis of energy band model and a suitable gas sensing mechanism has been established as well.

Shape memory polymers have received widespread attention from researchers because of their low density, shape variety, responsiveness to the environment, and transparency. This study deals with heat-shape memory polymers (SMPs) based on polylactic acid (PLA) for designing and fabricating a novel porous vascular scaffold to treat vascular restenosis. The solid isotropic material penalization method (SIMP) was applied to optimize the vascular scaffolds. Based on the torsional torque loading of Hyperworks Optistruct and the boundary conditions, the topological optimization model of a vascular scaffold unit was established. Forward and reverse hybrid modeling technology was applied to complete the final stent structure’s assembly. The glass transition temperature for the present SMPs is 42.15 °C. With the increase in temperature, the ultimate tensile strength of the SMPs is reduced from 29.5 MPa to 11.6 MPa. The maximum modulus at room temperature was around 34 MPa. Stress relaxation curves show that the material classification is a “thermoset” polymer. The superb mechanical properties, the transition temperature of the SMPs, and the recovery ratio made it a feasible candidate for a vascular scaffold. A circular tube based on the shape memory polymers was presented as an example for analyzing the recovery ratio in an unfolding state. A higher recovery ratio was obtained at a temperature of 65℃ with a tube thickness of 2 mm. Finally, the proposed porous vascular scaffold was successfully fabricated, assessed, and compared with the original and previously developed vascular scaffolds. The proposed scaffold structure regains its initial shape with a recovery ratio of 98% (recovery temperature of 47 °C) in 16 s. The tensile strength, Young’s modulus, and bending strength of the proposed scaffold were 29.5 MPa, 695.4 MPa, and 6.02 MPa, respectively. The results showed that the proposed scaffold could be regarded as a potential candidate for a vascular implantation.