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Tunable optical properties of silver–dielectric–silver nanoshell including surface plasmon resonance (SPR) and resonance light scattering (RLS) based on quasi-static theory are investigated. When the silver core radius increases, the longer resonance wavelength red shifts and light scattering cross-section decreases whereas the shorter resonance wavelength blue shifts and the light scattering cross-section increases. The effect of middle dielectric thickness on the light scattering cross-section of nanoshell is different from those of the silver core radius changes. As middle dielectric radius increases, the longer resonance wavelength first blue shifts and then red shifts and the light scattering cross-section increases whereas the shorter resonance wavelength always red shifts and the light scattering cross-section decreases. The sensitivity of RLS to the refractive index of embedding medium is also reported. As the silver core radius increases, the sensitivity of silver–dielectric–silver nanoshell decreases whereas increasing the middle dielectric thickness leads to increase the sensitivity of silver–dielectric–silver nanoshell. Tunable optical properties of silver–dielectric–silver nanoshell verify the biosensing potential of this nanostructure.

In this paper, two-dimensional thermoelastic analysis of a functionally graded nanoshell is presented based on nonlocal elasticity theory. To formulate this problem, first-order shear deformation theory (FSDT) is used for axial and radial deformations simultaneously. Material properties are assumed to be mixture of ceramic and metal based on a power law distribution. Principle of virtual work is used for derivation of the governing equations. The analytical approach is presented based on eigenvalue and eigenvector method to derive four unknown functions including radial and axial displacements and rotations along the longitudinal direction. In addition, the influence of nonlocal and in-homogeneous index parameter is studied on the responses of the system. Two-dimensional results are presented along the radial and longitudinal directions.

The thermo-electro-mechanical nonlinear vibration of circular cylindrical nanoshells on the Winkler–Pasternak foundation is investigated. The nanoshell is made of functionally graded piezoelectric material (FGPM), which is simulated by the nonlocal elasticity theory and Donnell’s nonlinear shell theory. The Hamilton’s principle is employed to derive the nonlinear governing equations and corresponding boundary conditions. Then, the Galerkin’s method is used to obtain the nonlinear Duffing equation, to which an approximate analytical solution is obtained by the multiple scales method. The results reveal that the system exhibits hardening-spring behavior. External applied voltage and temperature change have significant effect on the nonlinear vibration of the FGPM nanoshells. Moreover, the effect of power-law index on the nonlinear vibration of the FGPM nanoshells depends on parameters such as the external applied voltage, temperature change and properties of the Winkler–Pasternak foundation.

An accurate buckling response analysis for functionally graded graphene platelet (GPL) reinforced piezoelectric cylindrical nanoshells subject to thermo-electro-mechanical loadings is presented by a rigorous symplectic expansion approach. Three types of GPL reinforced patterns are considered, and the modified Halpin–Tsai model is employed to determine their effective material properties. By using Eringen’s nonlocal stress theory and Reissner’s shell theory, new governing equations are established in the Hamiltonian form. Exact solutions are expanded into symplectic series and three possible forms are derived. A comparison with the existing study is presented to validate the solution and very good agreement is observed. The effects of material and geometrical properties of GPLs, electric voltage and temperature rise on critical buckling stresses are investigated and discussed in detail.

A wild type virion, bacteriophage T4, was used as an organic template for the controlled synthesis and organization of Pt nanoparticles and nanoshells on its capsid. A long incubation of T4 virions with the metalchloride solution is necessary to the specific binding of the external surface of T4 capsid with Pt^IV by means of interactions between Pt^IV and the chemical functionality found inherently on the surface of the proteinaceous viral capsid. After chemical reduction with dimethylaminoborane (DMAB), the highly dispersive Pt nanoparticles with a uniform size of 3–4 nm were synthesized and covered the whole viral capsid. The packing density of Pt nanoparticles was enhanced by increasing the incubation cycles of the virions in metal salt solution. Moreover, Pt@T4 shell/core structures could be achieved by increasing the amount of metal ions around virons. UV/vis spectroscopy was used to follow the course of the reaction, and the formation mechanism was discussed. Both the small Pt nanoparticles and Pt@T4 shell/core structures show high electrocatalytic activity in electrochemical measurement, and therefore are expected to have potential applications in electrocatalysis.