J. Flores-Méndez; R. Pérez Cuapio; C. Bueno Avendaño; Martín Hernández-Ordoñez; M. Aparicio Razo; F. Candia García; I. Vivaldo-De la Cruz; R. C. Ambrosio Lázaro; B. Zenteno-Mateo
Abstract
This review summarizes progress about a recent homogenization theory based on the Fourier formalism for solid phononic crystals, which is valid for arbitrary Bravais lattice and any form of inclusions in the unit cell. The theory provides explicit expressions for the tensors of the effective nonlocal ...
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This review summarizes progress about a recent homogenization theory based on the Fourier formalism for solid phononic crystals, which is valid for arbitrary Bravais lattice and any form of inclusions in the unit cell. The theory provides explicit expressions for the tensors of the effective nonlocal elastic response (dependence on frequency and wave vector), namely the effective dynamic mass-density and compliance matrices. With the use of this theory, our predictions in the quasistatic limit for one and two-dimensional phononic crystals coincide with those of finite-element and asymptotic-homogenization methods. It is also shown that the derived expressions can be applied to phononic crystals with liquid components (two-dimensional sonic crystals) and agree with predictions of the multiple scattering theory. The formalism of non-local effects is fully demonstrated only for a one-dimensional elastic metamaterial having simultaneously negative effective dynamic mass density and elastic shear modulus. The development and applications of this homogenization theory, unlike other formalisms, arises from the inspiration of intense research efforts to simultaneously describe local and non-local effective properties in elastic periodic structures.
Suraksha Rasal; Sunita Jadhav;Pawan K. Khanna; Priyesh V. More; Chaitanya Hiragond
Abstract
ZnO/CdS core-shell hetero nanostructures with different shell thickness have been successfully developed by a solution chemistry method employing rapid homogenization concept. The obtained core/shell nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy ...
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ZnO/CdS core-shell hetero nanostructures with different shell thickness have been successfully developed by a solution chemistry method employing rapid homogenization concept. The obtained core/shell nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDX), FTIR, Raman, photoluminescence (PL), and UV-visible spectroscopy. All analytical and spectroscopic tools supported the formation of CdS shell over ZnO core. ZnO/CdS core-shell nanostructures were evaluated for their photocatalytic activity against methylene blue (MB), a common industrial water pollutant. It was observed that the ZnO/CdS core-shell nanostructures can effectively function as a photocatalyst under both UV and sunlight for degradation of MB. It was also observed that the degradation of MB was higher from core/shell nanostructures than the physical mixture of ZnO-CdS which was prepared separately.