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Polycrystalline Cu(In,Ga)Se2 (CIGS) thin films were grown on molybdenum-coated soda-lime glass substrates by co-evaporation of the elements Cu, In, Ga and Se from independent sources. The effect of electron irradiation on the electrical and optical properties of CIGS thin films and solar cells with the structure ZnO:Al/i-ZnO/CdS/CIGS/Mo/glass was studied. It was found that the degradation of the electrical parameters of solar cells (open-circuit voltage, short-circuit current density and efficiency) took place due to the formation of radiation defects (recombination centers) with deep energy levels in the bandgap of CIGS. It was revealed that after electron irradiation intensity of near band-edge luminescence band at about 1,1 eV decreased considerably and bands of luminescence with maxima at 0,93 and 0,75 eV appeared.

This study offers a comprehensive investigation into the parameters affecting the sound transmission characteristics of a double-walled sandwich magneto-electro-elastic cross-ply layered plate resting on viscoelastic medium in thermal environment. To this end, the walls of this sandwich structure are modeled based on the assumptions of the first-order shear deformation theory. The governing equations are derived via a coupled set of equations targeting vibration and acoustic aspects of the problem after the application of Hamilton's principle. The obtained equations are then solved by the implementation of double Fourier series and the second velocity potential, giving an accurate estimation of sound transmission loss under initial magnetic and electric potentials, variations of temperature, ply angle, acoustic cavity depth, incident angle of sound waves, and viscoelastic parameters., (© 2022. The Author(s).)

The multidisciplinary nature of piezoelectric (PZ) structures necessitates precise and efficient methods to express their behavior under different conditions. This article extends the general usage of PZ materials by introducing acoustic and fluid loading effects in a way that an unfilled multilayer cylindrical nanoshell with a functionally graded (FG) material core and PZ layers is subjected to preliminary external electric load, acoustic waves and external flow motion. As the properties of a functionally graded material changes along the shell thickness, a power law model is assumed to be governing such variations of desired characteristics. Evidently, this system includes different types of couplings and a comprehensive approach is required to describe the structural response. To this aim, the first-order shear deformation theory (FSDT) is used to define different displacement components. Next, the coupled size-dependent vibroacoustic equations are derived based on in conjunction with nonlocal strain gradient theory (NSGT) with the aid of Hamilton's variational principle and fluid/structure compatibility conditions. NSGT is complemented with hardening and softening material effects which can greatly enhance the precision of results. It is expected to use the findings of this paper in the optimization of similar systems by selecting suitable FG index, incident angle of sound waves, flow Mach number, nonlocal and strain gradient parameters, starting electric potential and geometric features. One of the important findings of this study is that increasing the electric voltage can obtain better sound insulation at small frequencies, specially prior to the ring frequency., (© 2022. The Author(s).)