Modern Physics Letters B

The mechanical and thermodynamic behaviors of intermetallics in Al–Zn–Mg–Cu alloys are studied by first-principles calculations. All studied second phases have negative values of formation enthalpy and cohesive energy indicating their excellent thermodynamic stability. Al₃Er_D0${}_{22}$ has the most significant metallic nature, while Mg₂Si shows the least metallicity. TiAl₃ shows the highest bulk, shear, and Young’s moduli. All Al₃M polymorphs, Mg₂Si and TiAl₃ phases show covalent/metallic hybrid bonding. The mechanical anisotropic behaviors obey the trend of: MgZn${}_2>{\mathrm{\text{Al}}}_3$Er_D0${}_{22}>{\mathrm{\text{Al}}}_3$Sc_D0${}_{22}>{\mathrm{\text{TiAl}}}_3>{\mathrm{\text{Al}}}_3$Sc_D0${}_{23}>{\mathrm{\text{Al}}}_3$Er_D0${}_{23}>{\mathrm{\text{Al}}}_3$Er_L1${}_2>{\mathrm{\text{Al}}}_3$Sc_L1${}_2>{\mathrm{\text{Mg}}}_2$Si, where MgZn₂ is the most mechanically anisotropic phase. The calculated room-temperature linear thermal expansion coefficient values for the studied phases are from $10.2\times 10^{-6}$ K${}^{-1}$ to $21.2\times 10^{-6}$ K${}^{-1}$; where Al₃Er_L1₂ has the highest value ($17.3\times 10^{-6}$ K${}^{-1})$, followed by Al₃Sc_L1₂ ($15.5\times 10^{-6}$ K${}^{-1})$; both of which are close to that of the Al matrix, thus making the relatively lower thermal misfit.

Mg:Fe:Cu:LiNbO₃ crystals with different [Li]/[Nb] ratios (0.946, 1.05, 1.20, 1.38) were prepared by the Czochralski method. The crystal structure and the occupancy of impurity ions were analyzed by X-ray diffraction (XRD). The effective segregation coefficient was analyzed by an inductively coupled plasma-atomic emission spectrometer (ICP-AES). The optical uniformity of the crystal is analyzed by birefringence gradient. The results show that the dopant ions do not change the crystal structure, and the concentration of dopant ions changes with the ratio of [Li]/[Nb]. The greater the ratio of [Li]/[Nb], the better the optical uniformity. Finally,we conclude that when the [Li]/[Nb] ratio approaches 1.20, the intrinsic defects of Mg:Fe:Cu:LiNbO₃ crystals almost disappear and the crystals approach the stoichiometric ratio. When the [Li]/[Nb] ratio is 1.38, the optical uniformity of the crystal is the best.

We encounter scalar fields everywhere in nature, although some may seem fainter than in the early universe. The models of this field having the logarithmic non-linearity are considered in inflation cosmology and supersymmetric field theories especially Q-ball dynamics model, quantum mechanics and nuclear physics. Till now, numerical studies and theoretical analysis of the considered problems have been studied. Purpose of the study is to obtain the analytical solutions of the Q-ball dynamics model via the ansatz-based method. The results have been seen in the literature for the first time to the best of our knowledge. The resulting solutions are useful in interpreting the study of wave propagation and have many applications in physics and the multidisciplinary audience.

The optical properties of the ZnGa₂Se₄ are investigated by infrared (IR) reflectivity, Raman scattering, photoluminescence and DFT simulations. We have analyzed pairs of lines of FL corresponding to 1.24eV and 1.22eV at low energy excitations, about these FL maxima haven’t any information in other works. Studies show that depending on the temperature, the intensity of luminescence decreases and formed new third maximum. The energy difference between each of these peaks is 0.02eV, which corresponds to the energy of the most intense phonon in the Raman spectrum.

In this paper, the variational iterative method (VIM) with the Laplace transform is utilized to solve the nonlinear problems of a simple pendulum and mass spring oscillator, which corresponds to the Duffing equation. Finding the Lagrange multiplier (LM) is a significant phase in the VIM, and variational theory is frequently employed for this purpose. This paper demonstrates how the Laplace transform can be utilized to locate the LM in a more efficient manner. The frequency obtained by Laplace-based VIM is the same as that defined in the already existing methods in the literature in order to ensure the clarity of the results. Numerous analytical techniques can be used to solve the Duffing equation, but we are the first to do it using a Laplace-based VIM and a distinctive LM. The fundamental results of my paper are that LM is also the same in the Elzaki transformation. In the vast majority of instances, Laplace-based VIM only requires one iteration to arrive at an answer with high precision and linearization, discretization or intensive computational work is required for this purpose. Comparing analytical results of VIM by Laplace transform to the built-in Simulink command in MATLAB which gives us the surety about the method’s applicability for solving nonlinear problems. Future work on the basic pendulum may examine the effects of nonlinearities and damping on its motion and the application of advanced control mechanisms to regulate its behavior. Future research on mass spring oscillators could examine the system’s response to random or harmonic input. The mass spring oscillator could also be used in vibration isolation to minimize vibrations from one building to another.

In this paper, the generalized Kudryashov (GK) approach and the sine-Gordon expansion approach are used for constructing new specific analytical solutions of the deoxyribonucleic acid model, which include the well-known bell-shaped soliton, kink, singular kink, periodic soliton, contracted bell-shaped soliton and anti-bell-shaped soliton. The efficacy of these strategies demonstrates their utility and efficiency in addressing a wide range of integer and fractional-order nonlinear evolution problems. The physical relevance of the demonstrated results has been proven using three-dimensional forms. It is interesting to mention that the solutions achieved here using the provided methods are extra-extensive and may be used to explain the internal interaction of the deoxyribonucleic acid model originating in mathematical biology. The suggested approach was utilized to get exact traveling wave solutions for fractional nonlinear partial differential equations appearing in nonlinear science.

This study explores the novel solitary wave solutions of the perturbed Chen–Lee–Liu (CLL) equation, aiming to elucidate the physical and dynamic behaviors of pulses in optical fiber. The perturbed CLL equation is derived from the well-known Schrödinger equation and serves as an iconic model. Two analytical techniques are employed to obtain these novel solitary wave solutions. Subsequently, these solutions are subjected to objective analysis using a widely recognized semianalytical scheme to comprehend their underlying mechanisms. Multiple graphs with diverse styles are utilized to illustrate the analysis of pulse waves in optical fiber and assess the accuracy of the analysis. The scientific novelty of this research lies in providing a comprehensive explanation through a comparative analysis of our recently published results in related research papers.

Dynamic quantum secret sharing occupies an important position in quantum cryptography. In this paper, an efficient and secure dynamic quantum direct two-secrets sharing scheme is proposed based on the GHZ state. The proposed scheme is a one-time sharing of a determined classic message and quantum states. For recovering the secret messages, the agents only need to have the ability to perform X-basis measurements on the particles without performing any unitary operation. When dynamically deleting agents, our scheme only requires the other agents to announce some information without transmitting any quantum. Moreover, the analysis shows that our scheme is able to resist dishonest revoked agent attack as well as a range of other common attacks. Compared with the existing dynamic quantum direct secret sharing schemes, the proposed scheme is more efficient and more secure.

We have investigated the impact of three different soiling types (dust, leaf, rainfall) on the current–voltage and power–voltage characteristics of a solar panel located at different locations. The current and power losses were measured regularly for 50 days (10-day interval). The soiling ratio was calculated to be a reliable parameter for soiling impact assessment. The source of current and power losses due to soiling was rooted by measuring the transmittance loss and panel surface temperature increase, external quantum efficiency and electroluminescence spectrum recorded for the range of 950–1300 nm. The results confirm leaves as the most detrimental soling type with 38% power loss compared to dust and raindrop and the lowest loss in current density and power was related to raindrop (29%). This is confirmed by the significant decrease in the soiling ratio of the leaf-soiled panels from 0.9 to $<0.1$ in 50 days. Electroluminescence spectra confirm the critical impact of leaf-soiling on defect generation in the materials and a reduced photocurrent generation. Leaf could reduce the current and power of the panel from 14A to 12A and from 190W to 100W, respectively.

This paper presents an analytical solution for a complex mechanical system consisting of a pendulum with a rolling wheel, which combines translational and rotational motion. The system’s dynamics are described by a set of coupled differential equations that are challenging to solve analytically using traditional methods. To overcome this challenge, the variation iteration method (VIM) is employed to derive an analytical solution. VIM is a powerful technique that allows for the approximate solution of differential equations by constructing a series solution iteratively. The Lagrange multiplier, a crucial component in the solution process, is determined for the first time using the Elzaki transformation. Interestingly, the Lagrange multiplier obtained through the Elzaki transformation matches the result obtained from Laplace transformation, which is a fundamental finding of this paper. Also we compared its results with the by employing the VIM and the derived Lagrange multiplier, a comprehensive analytical solution for the complex pendulum with a rolling wheel system is obtained. The solution provides insights into the system’s behavior, such as the oscillation amplitudes, angular velocities and other relevant dynamic parameters. The proposed approach demonstrates the efficacy of the VIM in tackling complex mechanical systems and showcases the equivalence between the Lagrange multiplier derived through Elzaki transformation and the well-established Laplace transformation. The results obtained from this study contribute to the understanding and analysis of coupled translational and rotational systems, providing a valuable tool for researchers and engineers working in the field of mechanical dynamics. Sketches are made of the phase portraits close to the equilibrium points.

The objective of this work is to show that simple modifications in the form of the fermion–fermion interacting potential generate widely different thermodynamic behaviors, with macroscopic manifestations reflected by the thermal free energy. This is done by appealing to quantum statistical mechanics, in its Gibbs’ ensemble formalism, employing two different SU2 exactly solvable models. Some intriguing aspects of the fermion dynamics are uncovered. We conclude that, in investigating fermion dynamics, minute changes in the Hamiltonian may lead to dramatic consequences in the behavior of the Helmholtz’ free energy.

Based on the density functional theory, the electronic, optical and thermoelectric properties of the Cu₂FeSnS₄ two-dimensional (2D) structure are investigated. The total energy of unit cell changes the curve in terms of its volume which indicates an equilibrium volume for this compound. The density of states and band structure show that the compound has half-metallic behavior with an electron gap of 0.7eV at up spin. The merit coefficient at high spin up to room temperature is in the range of 0.9 and is stable, making it a suitable option for thermoelectric applications.