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AbstractIn advanced materials engineering, understanding transient vibrations in sandwich annular plates reinforced by multi-phase nanocomposites is essential. To adequately represent the geometry of these systems, a generic cylindrical coordination system is often used in modeling. The heterogeneous laminated plate is homogenized into an analogous uniform medium to facilitate analysis. In order to represent precise stress and strain distributions, taking into account rotating inertia and transverse shear deformation, a higher-order theory based on a hyperbolic function is used. The governing equations of motion are derived using Hamilton’s principle in polar coordinates, guaranteeing compliance with energy laws. The 2D generalized differential quadrature (GDQ) method effectively discretizes the governing equations for numerical solutions while retaining a high degree of accuracy in recording transient reactions. Furthermore, by solving the differential equations in the frequency domain, the Laplace transform approach sheds light on the dynamic behavior of the system. Using the deep neural networks (DNNs)-fuzzy approach improves the prediction of these composite structures’ vibrational activity. This hybrid approach uses fuzzy logic to control uncertainty and DNN for pattern identification. The DNN-fuzzy approach reliably predicts the intricate vibrational properties of multi-phase sandwich systems reinforced with nanocomposite using datasets from mathematical modeling. This combined use of mathematical techniques, theoretical models, and predictive algorithms improves our knowledge of complex composite structures’ transient vibrations and makes them more useful in a range of engineering domains. [ABSTRACT FROM AUTHOR]

Mn3O4 (MO) nanoparticles have drawn a lot of attention due to their use in batteries, ion exchange, sensors, and catalysts in various oxidation states. Here, prior to developing new hybrid freestanding films with different MO nanoparticle concentrations (0, 0.037, 0.37, and 3.7 wt%), it was essential to first manage the electrical and optical properties of the PVA/PVP blend. Several methods, including high-resolution transmission electron microscopy, Atomic force microscope, FTIR, and XRD, were accustomed to verifying the emergence of the polymeric nanocomposite (PNC) films. The correlation between both the optical and dielectric properties of the films and the bandgap was altered using the doping ratio. In terms of its optical properties, MO is observed to have a significant impact on pure PVA/PVP, including the indirect optical energy gap, the localized state's order, the absorption coefficient, and the response of optical conductivity. Hervé–Vandamme, Moss, Singh-Kumar, and Ravindra are a few models that have studied the connection between energy gaps and refractive index. Moreover, PVA/PVP/xMn3O4 polymer nanocomposite samples with varied MO levels were examined for their linear together with nonlinear optical properties (NLOP). The exclusion of both ordinary and laser light is studied in the PVA/PVP enriched MO (NPs) samples that were created. Moreover, there are sharp decreases in the laser transmitted power from 315.88 to 13.6 mW for the pure blend to 0.135 and 0.00039 for PNC/3.75Mn3O4 nano-composition using a laser source of 623.8 and 533 nm, respectively. Thus PNC/3.75Mn3O4 sample is recognized as a good prospect for relatively inexpensive optical limiting and laser filter innovation. [ABSTRACT FROM AUTHOR]

Transition metal oxide (TMO)—filled polymer films have numerous applications, including electromagnetic shielding and nonlinear optical devices. Nb2O5‐filled polyvinyl pyrrolidone (PVP)/polyvinyl alcohol (PVA) blend was prepared using a solution casting process. Pristine and nanocomposite films from these blends were studied. X‐ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier infrared spectroscopy confirmed the formation of nanocomposites via interfacial interactions between the polymer chains and Nb2O5 nanoparticles. These nanoparticles influence the amorphous nature and transparency of the PVA/PVP blends. The improvement of Dopt (optical density) becomes particularly obvious in blended polymer films with considerable Nb2O5‐nanofiller concentrations. By increasing the weight percentage of Nb2O5, the probability of producing additional levels in the bandgap increased. The optical absorption coefficient of each nanocomposite film was less than 106 m−1, indicating indirect electron transfer. Thus, the indirect optical band‐gap declined from 3.9 to 1.9 eV as calculated from Tauc's and the absorption spectral fitting (ASF) formula. Additionally, the effects of Nb2O5 on the extinction coefficient, refractive index, high‐frequency (ε∞), and static‐frequency (εo) dielectrics have been reported. The nonlinear refractive index and optical susceptibilities (x1 and x3) were enhanced by increasing the Nb2O5 content in the blend. The penetration depth (δ) and optical limiting (OL) properties were also investigated. The developed nanocomposite materials could be used for advanced technology‐based devices such as reflective coatings, opto‐linear, and nonlinear optoelectronic applications. [ABSTRACT FROM AUTHOR]