The article aims to depict the influence of one relaxation time on elastic and thermal waves propagating through an isotropic medium. The medium is half-space and homogenous in nature. The thermal properties of the particles are influenced by thermodynamic and conducive temperature. Along with all these conditions we have also considered the medium to be under the impact of an primarily functional magnetic field with uniform intensity. Firstly, we developed the theory of generalized surface waves and employed it to investigate some cases of wave propagation. Secondly, in the physical domain, the harmonic vibrations of a half-space are used to obtain expressions for field variables involved in the mathematical model. The surface of the medium is under the constraint of Mode-I crack. A numerical application is presented for a particular material to illustrate the study graphically.

The simplified strain gradient elasticity theory (SSGT) is used to study the induced flexoelectric effect in an anisotropic dielectric beam due to bending. The beam cross-sections are uniform with internal cubic structure symmetry. Three different cases are studied in the context of the Timoshenko beam theory. In the first two cases, the simply supported beam subjected to uniformly distributed or graded forces at the lateral surface of the beam are considered, while the third case is devoted to study the clumped-free ends beam problem subjected to graded force. With appropriate boundary conditions, a closed-form solution is obtained for the problem filed equations. The study shows that, when the applied force is concentrated at the center region of the beam, the induced spontaneous polarization is directed towards the beams two ends. While, when the beam is clamped from one end, the induced spontaneous polarization moves towards the applied force.

The static bending and the flexoelectric effect induced in an anisotropic dielectric nano-plate are studied in the frame of the simplified strain gradient elasticity theory (SSGT). The Kirchhoff plate theory is considered for a simply supported nano-plate loaded by a uniformly distributed constant forces at its upper surface. The displacement and the induced spontaneous polarization are formulated such that the dimensions of the problem reduce to two dimensions only. The variational concept of the internal energy and the virtual work exerted by the external forces are used to obtain the governing equations as well as the boundary conditions. The choose of the cubic materials avoid the ambiguity between piezoelectricity and flexoelectricity, where all odd tensors are vanished. The finite Fourier transform is employed to obtain the analytical solution. The numerical calculations of the problem are presented with the help of the commercial software Maple. Some selected significant results are introduced through sets of figures with physical explanations. The results reveal that the flexoelectric effect at the surface of the clamped nanoplate should be considered and cannot be neglected. Moreover, the nanoscale dimension enhances the flexoelectric effect more than macroscale.

In this article, we study the flexoelectricity induced in a prismatic anisotropic bar due to torsion. The simplified strain gradient elasticity theory is considered in this study. The bar is uniform, that is, any cross-section of the bar has a rectangular shape with cubic internal structure symmetry. The traction and higher traction forces effect on the deflection and spontaneous polarization of the bar with different boundary conditions are also discussed. The induced wedge forces are also considered during this study. The magnesium oxide (MgO) physical quantities values are chosen to present a numerical example as one of the practical applications of the problem. The results are discussed and introduced graphically. The most interesting finding in this study is the wedge force directions. When the displacements inside the cross-section of the bar are uniformly distributed, the resultant wedge forces have the same inclination with the cross-section boundary. Meanwhile, if the displacement is not uniformly distributed, the wedge force inclinations with the cross-section boundary are not equal.

Steady two-dimensional motion of an incompressible non-Newtonian Nanofluid through porous medium over a semi-infinite moving plate is studied . The system is stressed by an external uniform magnetic field. The heat and mass transfer are considered with the flow of non-Newtonian fluid which obeys the Eyring–Powell model. The problem is mathematically formulated and solved numerically using the ParametricNDSolve-Mathematica package. The effects of the physical parameters of the problem such as, permeability, chemical reaction as well as the fluid material parameters Hartmann number, Eckert number and Reynolds number are discussed and illustrated in figures with some important applications. The results show that the fluid velocity increases with the increases of porosity parameter as well as the material parameter, but it decreases with the increase of the magnetic field. Increasing the magnetic field decreases porosity, temperature and concentration. The effects of some physical quantities on fluid velocity distribution can be neglected.

The objective of this paper is to investigate the surface waves in fibre-reinforced anisotropic elastic medium subjected to magnetic and thermal fields. We introduce the coupled theory (CD), Lord-Shulman (LS) theory and Green-Lindsay (GL) theory to study the influence of magnetic field on 2D problem of a fibre-reinforced thermoelastic. The analytical expressions for displacement components and force stress are obtained in the physical domain by using the harmonic vibrations. The wave velocity equations have been obtained in different cases. Numerical results for the temperature, displacement, and thermal stress components are given and illustrated graphically in the presence and absence of the magnetic field of the material medium. A comparison is also made between the three theories in the case of presence and absence of fiber-reinforced parameters.

A novel model of two-dimensional deformationsfor two-temperature theory at the free surface under the excitation of thermoelastic wave by pulsed laser for a semi-infinite semiconducting medium is studied. The effect of mechanical force during a photothermal process is investigated. The mathematical methods of the Lord-Shulman (LS includes one relaxation time) and Green-Lindsay (GL with two relaxation times) theories as well as the classical dynamical coupled theory (CD) are used. An exact expression for displacement components, force stresses, carrier density and distribution of temperature are obtained using the harmonic wave analysis. Combinations of two-temperature and photothermal theories are obtained analytically. Comparisons of the results are made between the three theories also. The effects of thermoelectric coupling parameter, two-temperature parameter on the displacement component, force stress, carrier density, and distribution of temperature for silicon (Si) medium have been illustrated graphically. The variations of the considered variables with the horizontal distance have been discussed. (C) 2017 Elsevier Ltd. All rights reserved.

A novel technique is used to investigate the influence of magnetic field for a two dimensional deformations on a two temperature problem at the free surface of a semi-infinite medium. The investigation is carried out under the effects of both mechanical force and hydrostatic initial stress during a photothermal excitation theory. The equations of elastic waves, heat conduction equation, quasi-static electric field, carrier density, two temperature coefficient, ratios, and constitutive relationships for the thermo-magnetic-electric medium are obtained using the Harmonic Wave Method (HWM) technique. The effects of thermoelastic, thermoelectric and two temperature parameters of the applied force on the displacement component, force stress, carrier density and temperature distribution has been depicted graphically.

In this paper, boundary value problems in half-space with different types of heatingare solved by using two-dimensional deformations of the theory of two-temperature thermoelasticity. In particular, the governing equations are solved by using the harmonic waves methods under two theories: (a) the Lord-S, hulman (LS) and (b) the classical dynamical coupled theory (CD), with a linear opening Mode-I crack under the effect of mechanical force during the thermal shock type. Stress wave travels in a transient compressive manner along the crack faces, moving outward from the loading region on the crack face. The exact expressions for the displacement components, force stresses and temperature distributions have been obtained. The variations of the considered variables through the horizontal distance have been illustrated graphically. Comparisons have been made between the results obtained with the two theories. Numerical experiments have also been carried out for a suitable material with the aim of illustrating the results. The conductive temperature, the dynamical temperature, the stress and the strain distributions have been shown graphically, comparing and highlighting the main results.

Silver nanoparticles (NPs) in Triton X-100 were characterized by X-ray diffraction (XRD) and UV-Vis absorption spectra.UV-Vis spectrum showed a single peak at 442 nm due to the surface Plasmon resonance (SPR).Position of SPR peak exhibited a red shift after the sample was exposed to UV irradiation (unfiltered light).The optical band gap values have a reduction from 2.46 to 2.37 eV after irradiation for 960 minutes.Such reduction in optical band gap may be due to change in particle size which calculated using Mie theory.For Luminescent solar concentrators (LSC), it is important to enhance the fluorescence quantum yield (FQY) and photo stability.Our measurements have demonstrated that the addition of Silver nanoparticles to dye solution causes broadening of absorption bands, so the spectral range of sunlight absorbed by LSC has increased.The photo stability of organic dyes used was improved after adding Silver nanoparticles.The area under fluorescence spectra of dyes with Silver NPs increased by 41-31 % when compared with identical dye concentrations without Silver nanoparticles as a result of interaction of the species with Silver NPs.