The mechanical, electronic and thermoelectric calculations of the KMgP half-Heusler compound and its [111] thin films have been done in the framework of density functional theory. The KMgP bulk has mechanical stability in the static and dynamic viewpoints, and it has the p-type semiconductor behavior with the 1.1-eV energy gap. The KMgP in the bulk phase is a relatively good thermoelectric compound

The study is concerned with entropy minimization on three-dimensional magnetohydrodynamic Oldroyd-B fluid flow with relaxation–retardation viscous dissipation and a mixed chemical reaction. A numerical solution of the nonlinear transport equations is obtained using an overlapping grid spectral collocation numerical scheme. We investigate strategies for entropy generation minimization in terms of system

In this paper, the nonlinear ion acoustic rogue waves (IARWs) are investigated in an unmagnetized, collisionless plasma which consist of positive ions, superthermal electrons and positrons, respectively. A nonlinear Schrödinger equation (NLSE) of IAW packets has been obtained by using the reductive perturbation technique. Furthermore, the effects of superthermal electrons and positrons on the nonlinear

The present study reports daily, monthly, and seasonal variations of aerosol optical depth (AOD) using aerosol robotic network (AERONET), MICROTOPS-II Sunphotometer, and Moderate Resolution Imaging Spectroradiometer (MODIS) data over three most polluted cities such as Kanpur, Varanasi, and Jaipur in the Indo-Gangetic Plain during 2011–2015. The monthly mean variations of AOD and Angstrom Exponent were

In this paper, barrier height (\(\phi_{{\text{b}}}\)) and depletion layer width (Wd) of ITO-coated glass/Methyl Red (MR) dye/Aluminum (Al)-based organic device have been studied, and effect of single-walled carbon nanotubes (SWCNT) on both of these parameters has been observed. ITO-coated glass as front electrode and Aluminum as back electrode are used to form the device by using spin coating technique

In this study, rare earth element terbium doped Ni0.4Cu0.2Zn0.4TbxFe2−xO4 (where X = 0.0 to 0.1 in steps of 0.025) were synthesiesed by citric acid as catalyst via auto-combustion route. The structural, morphological, spectral and magnetic properties are explored and studied in detail. The ferrite samples were characterized by energy dispersive X-ray analysis (EDAX), X-ray diffraction of XRD, field

Q-switched fiber laser with a tunable wavelength output is experimentally demonstrated utilizing a nonlinear saturable absorption of vanadium pentoxide (V2O5) in conjunction with a tunable bandpass filter (TBF). The V2O5 saturable absorber (SA) was prepared by mixing V2O5 with polyethylene glycol. The SA film exhibits a modulation depth of 7% with a saturation intensity of 90 MW/cm2. By integrating

Cadmium telluride (CdTe) thin films with a nanocolumnar morphology were grown on glass substrates using the Sublimated Vapor Effusion Deposition technique and a rotational source in counter-rotation with respect to the substrate. Afterward, it was proceeded to coat with silver nanoparticles whose average size was of ~ 100 ± 40 nm. X-ray diffraction analysis showed that all samples presented the zinc-blend

In this work, we present a new vacancy model which proves that both lithium and tantalate (niobium) vacancies can coexist in the lattice structure of lithium tantalate and lithium niobate. Using the theoretical approach to the defect structure analysis, which is developed by Safaryan, a comparison between three defect models (tantalate/niobium vacancies, lithium vacancies, and mixed vacancies) has

In this research work, we consider the two-dimensional time-dependent laminar hydromagnetic boundary-layer flow of a bio-magnetic fluid over a wedge using a micropolar fluid model with convective boundary conditions and taking into account the action of a transversely magnetic field. The partial differential equations that govern velocity, temperature and micro-rotation are transformed into nonlinear

This paper reveals about a stable flat cosmological model which has been constructed, and the evolution of dark energy has been investigated in the framework of the recently suggested non-Lagrangian \(\kappa (R,T)\) modified gravity (Terule, Eur Phys J C 78:660, 2018). The toy model we are presenting in the current work reveals some interesting cosmological features consistent with observations and

The heat transfer in flow past thin needle has applications in instruments like hot wire anemometers. The objective of this article is to study the influence of hybrid nanoparticles on heat transfer distribution of the boundary layer flow over a parabolically shaped thin hot needle. The Sakiadis and Blasius 2-D flow scenarios have been analyzed by implementing a mathematical model with the Navier–Stokes

Molecular dynamics simulation of Germania (GeO2) melt at different densities has been carried out to investigate the microstructural transformation, polyamorphism and structural heterogeneity. The structure of GeO2 is studied by GeOx basic units and their cluster. The simulation results show that the structure of GeO2 is formed by GeOx structural units linking to each other via with corner-sharing

Gravitational well is a widely used system for the verification of the quantum weak equivalence principle (WEP). We have studied the quantum gravitational well under the shed of noncommutative (NC) space so that the results can be utilized for testing the validity of WEP in NC-space. To keep our study widely usable, we have considered both position–position and momentum–momentum noncommutativity. Since

Angle and polarization-dependent tunable transmission properties of a one-dimensional (1D) ternary photonic crystal (TPC) whose period consists of three alternate layers of two different kinds of single-negative [Epsilon-negative (ENG) and mu-negative (MNG)] media are theoretically investigated by using the transfer matrix method (TMM). It has been shown that the proposed polarizing filter is capable

The propagation of dust-acoustic waves in a dusty plasma bounded in finite symmetrical cylindrical geometry has been theoretically investigated. By using the reductive perturbation method, we obtain a quasi-nonlinear Schrödinger equation. It is shown that there is a dark envelope soliton under certain conditions, while its amplitude will decrease with the time. The dependence of both the dispersion

Surface plasmon resonance (SPR)-based fiber optic sensor using bi-layers of Pt-InN is theoretically reported. Sensitivity and figure of merit of the sensor are increased with an increase in the thickness of the Pt layer for all thicknesses of InN layers. For a particular thickness of the Pt layer, sensitivity gets bigger as the thickness of the InN layer is raised. Maximum sensitivity is attained by

In this research, we study the polytropic gas cosmology in a 5-dimensional form of the flat Friedmann–Robertson–Walker framework. In this context, we focus on the evolution of corresponding energy density and use the most recent data from the Type Ia Supernova, observational data of the cosmic Hubble parameter and the updated Planck-results to place constraints on the free parameters defined in the

This paper presents a case study of very low frequency (VLF) radio signal anomaly during a moderate geomagnetic storm (Kp = 6, Ap = 80 and Dst = − 60 nT) on September 10, 2018 followed by a moderate earthquake (M = 5.3) on September 12, 2018 which occurred near to (~ 80 km) a subtropical low latitude station Cooch Behar (CHB), India (26.345°N, 89.448°E). Signal amplitudes from the two transmitters

This work aims at presenting a new numerical solution to a nonlinear, one-dimensional problem of heat wave propagation in a thick slab of a rigid thermal conductor. The model predicts dependence of second sound velocity on temperature and heat flux. For this, an unconditionally stable numerical scheme is constructed using a kind of weighted average nonstandard finite difference discretization. Stability

In the framework of density functional theory, the first principle calculations are performed to investigate various physical properties of new series of half Heusler alloys KMnZ (Z = B, Si, Ge, As) by using WIEN2k code. The results of structural parameters show that ferromagnetic state is more stable, with Type 3, configuration than the non-magnetic and antiferromagnetic states for all KMnZ (Z = B

The primary focus behind this research work is to unfold the heat and mass transfer characteristics of peristaltic transport of hydromagnetic couple stress fluid through a porous medium in an inclined channel of asymmetric kind. Consideration of both Dufour and Soret effects is one of the key factors of this investigation. Simultaneous convective conditions of mass and heat transfer are satisfied by

In this study, the density functional theory has been used to perform the structural, electronic, magnetic and optical properties of the variant stable AgNiF3 (001) surfaces. The surface morphology is investigated under two truncations, namely AgNiF3/AgF (AgF) and AgNiF3/NiF (NiF). The enthalpy of formation, relaxation parameter and surface energy results show that the stable AgF and NiF surfaces can

In this research, the hydromagnetic natural convection of an incompressible fluid with point heat source by considering the influence of Hall current and induced magnetic field between infinite vertical walls is studied. The Laplace transform procedure is utilized to determine the analytical solutions of the acquired mathematical model with the wavelet function. With the derived solution of velocity

Perfect transfer of the two-qubit quantum information in spin chain without any magnetic field is investigated. In our work, the spin chain is placed in a particular low-intensity magnetic field whose value is symmetrical about the chain and whose difference value between the nearest lattice points is constant. And the influence of the magnetic field has been studied by the method of matrix diagonalization

The purpose of this manuscript is to investigate the unsteady magnetohydrodynamics flow of a Maxwell fluid with conjugate effects of heat and mass transfer under the slip and non-slip conditions at the boundary. Moreover, we apply the Caputo–Fabrizio fractional derivative to model the proposed problem. We consider the fluid in a porous medium over a vertical plate with ramped temperature. We take into

The purpose of this article is to use an algorithm to obtain a non-static solution to the Einstein–Euler equations of a spherically symmetric matter distribution of a perfect fluid. The equations obtained make up a nonlinear system of partial derivative equations (PDE), which in the vast majority of cases is quite difficult to solve, either analytically or numerically. In this context, the spherical

In this report, an investigation of the optical properties of the (C9H14N)3BiCl6 hybrid compound by UV–Visible spectroscopy was detailed. The measurements were taken at room temperature in the range 200 to 2400 nm. The optical direct band-gap Eg, determined by means of reflectance data, by absorbance data or by Tauc's method, was evaluated at (3.391 ± 0.009) eV, (3.409 ± 0.009) eV and (3.422 ± 0.102) eV

This article represents a possible geometric interpretation of the Aharonov–Bohm (A–B) effect. We presented a new curve in the context of Einstein–Maxwell geometry, using the Bazanski approach. In the context of the geometrization philosophy, this curve can be used as an equation of motion of a charged test particle in a combined gravitational and electromagnetic field. The new equation of motion obtained

The present paper illustrates the influence of the top Ag and Te thin layer on the linear and nonlinear optical properties of Ag(Te)/As50Se50 bilayer thin films. The As50Se50 and Ag(Te)/As50Se50 bilayer thin films were prepared by thermal evaporation technique under high vacuum conditions. The X-ray diffraction study showed no structural changes, whereas the UV–Visible spectroscopy data showed the

We study the gravitational collapse of a spherically symmetric anisotropic relativistic star within Einstein’s theory of gravity making use of one of our recently developed collapsing stellar models (Das et al. in Astrophys Space Sci 361:99, 2016). The final state of continual gravitational collapse of a massive star under regular initial conditions is analyzed in terms of the formation of black holes

In the COVID-19 pandemic era, undoubtedly mathematical modeling helps epidemiological scientists and authorities to take informing decisions about pandemic planning, wise resource allocation, introducing relevant non-pharmaceutical interventions and implementation of social distancing measures. The current coronavirus disease (COVID-19) emerged in the end of 2019, Wuhan, China, spreads quickly in the

An exertion is executed to explicate thermophysical aspects of viscoelastic fluid flow produced by a nonlinearized stretched surface. Here, viscoelasticity is characterized by Casson fluid model and expressed rheologically in momentum equation. Flow attributes of Casson fluid are thoroughly investigated under transversal magnetized field and along with provision of suction/injection to surface. Flow

In this work, we obtain the Klein–Gordon equation solutions for the Yukawa potential using the Nikiforov–Uvarov method. The energy eigenvalues are obtained both in relativistic and non-relativistic regime. The corresponding eigenfunction are obtained in terms of Laguerre polynomial. We applied the present results to calculate heavy-meson masses of charmonium \( c\bar{c} \) and bottomonium \( b\bar{b}

In the present contribution, efforts are made to develop an insight between two verticals of strong interaction phenomenology, namely the archaic Regge theory and an avant-garde Hadron dynamics. Even before the advent of quantum chromodynamics (QCD), Regge theory served as an effective tool in the understanding of the high energy limit of hadronic scattering processes and thereby Hadron dynamics. Regge

The present investigation is useful in medical engineering treatments, in which biothermal therapy is one of the popular treatments. The investigation of transport phenomena of fluid flow and heat in those applications requires multi-physical models featuring heat transfer and deformable porous media. In view of this, it is anticipated to study the influence of thermal buoyancy force and nonlinear

The Heusler compounds have been recognized not only for their applications in spintronic and memory devices but also for thermoelectric devices. In this paper, the electronic and thermoelectric properties of Mn2PtCo full-Heusler compound have been investigated by using the full-potential linearized augmented planewave method and the Boltzmann semi-classical Boltzmann transport theory, respectively

The nonlinear propagation of dust acoustic (DA) waves (DAWs) in an unmagnetized electron depleted dusty plasma (containing opposite polarity warm dust grains and non-extensive positive ions) has been theoretically investigated. The nonlinear Schrödinger equation (NLSE) is derived by employing the reductive perturbation method. It is observed that the dusty plasma system under consideration supports

This study reveals some new solitons solutions to the Kraenkel–Manna–Merle (KMM) system which describes the nonlinear ultra-short wave pulse motions in saturated ferromagnetic materials having external field with zero-conductivity. Various kinds of soliton solutions such as dark, bright, singular, combined dark bright, combined dark-singular solitons, periodic and singular periodic waves are successfully

Ce3+-doped KBr single crystals were grown by Bridgman–Stockbarger technique. The grown crystals characterization results on photoluminescence (PL), powder X-ray diffractometer (PXRD), Fourier-transform infrared spectroscopy (FTIR), Fourier-transform Raman spectroscopy (FT-Raman), scanning electron microscopy, Vickers microhardness tester (Hv), electron paramagnetic resonance spectrum (EPR) and dielectric

We have used non-extensive entropy to study the influence of the non-immunogenic tumor microenvironmental effects on dynamics of tumor growth. For this purpose, we have first employed the Tsallis and Abe entropies with different parameters. Then, we have applied the phenomenological model equation to determine the steady-state distribution for investigating tumor growth. Numerical results show that

According to the current perception, symptomatic, presymptomatic and asymptomatic infectious persons can infect the healthy population susceptible to the SARS-CoV-2. More importantly, various reports indicate that the number of asymptomatic cases can be several-fold higher than the reported symptomatic cases. In this article, we take the reported cases in India and various states within the country

Dust ion acoustic waves (DIAWs) are investigated analytically in the framework of damped forced Korteweg–de Vries–Burgers (DFKdVB) equation in an unmagnetized collisional dusty plasma consisting of negatively charged stationary dust grains, positively charged ions and q-nonextensive distributed electrons. Reductive perturbation technique is used to obtain the DFKdVB equation for DIAWs. The effects

In this paper, the variational quantum Monte Carlo method is applied to investigate the ground state of the lithium atom. Moreover, the energy eigenvalues of the lithium atom in dense plasma are also investigated by using the Debye–Hückel model and the exponential cosine screened Coulomb potential model. The calculations are carried out by using trial wave functions in the form of the Slater determinant

Bismuth titanate nanostructure, Bi12TiO20, (BTO) belonging to sillenite family was synthesized by chemical route at the sintering temperature 800 °C for a period of 6 h. The crystalline phase of the materials was investigated by the X-ray diffraction method. The morphology and particle size of the BTO sample were determined by scanning electron microscopy (SEM) and transmission electron microscopy

In this study, we introduce directional Fermi–Walker transportation along with the vortex lines of nonvanishing vector fields in the ordinary three-dimensional space. Moreover, we investigate the geometric phase and angular velocity vector (Darboux vector) of vortex lines. Then, we define directional magnetic and electric vortex lines by considering the Lorentz force law and electromagnetic force equation

In this paper, the spontaneous emission rate of an excited atom between the two dispersive and dissipative dielectric slabs is determined. It is assumed that the atom has a definite transition electric dipole moment, and the dielectric function of the slabs is an arbitrarily complex function of frequency satisfying Kramers–Kronig relations. In this research, by noting to the connection between the

This paper presents a computational modeling approach to analyze the peristaltic pumping of couple stress hybrid nanofluids regulated by the electroosmosis mechanism through a microchannel. The effects of applied magnetic field, Joule heating and buoyancy have also been computed. In this analytical model, water-based titanium dioxide (TiO2) and silver (Ag) hybrid nanofluids have been considered. For

Trivalent chromium is a very common ion used for coloring in the industry of glass. As glasses are melted under high oxidizing circumstances, hexavalent chromium Cr(VI) can be fixed and found in certain advertising applications of UV-protection receptacles. Melt quenching technique is employed to prepare oxide glasses with a general formula xNa2O–(30 − x) Li2O–10K2O–10ZnO–49.7B2O3–0.3Cr2O3 (where x = 0

The International Thermonuclear Experimental Reactor (ITER) tokamak can generate fusion energy in an acceptable method. In this study, the particle and energy equations were developed for \({\text{T}}\left( {{\text{D}},n} \right){}^{4}{\text{He}}\), \({\text{D}}\left( {{\text{D}},n} \right){}^{3}{\text{He}}\), \({\text{D}}\left( {{\text{D}},p} \right){\text{T}}\), and \({}^{3}{\text{He}}\left( {{\text{D}}

Europium-doped magnesium–zinc–sulfophosphate glasses of molar composition (65 − x) P2O5–20MgO–15ZnSO4–xEu2O3 (x = 0.0, 0.5, 1.0, 1.5 and 2.0) were prepared via melt-quenching method. The synthesized glasses were characterized at room temperature to determine the relationship between Racah and mechanical properties. The FTIR spectra of glasses in the range of 4000–400 cm−1 revealed the presence of characteristic

Photoelectrodes and sensitizers are the vital components of future low-cost dye-sensitized solar cells which are used to meet the present energy demand. Herein, ZnS–CdS thin film photoelectrodes (WE) prepared on steel substrate by electrodeposition method are sensitized by chlorophyll extract and combined with graphite counter electrode, both being dipped in sulphide–polysulphide redox electrolytes

Solar energy has environmental benefits by reducing the pollution and global warming resulting in cleaner water and air. One of the key factors is the absorber surface for entrapping the solar energy that is receiving from solar spectrum under the wavelength range of 250–2500 nm. Generally, absorber surfaces are made of thin films that are mechanically resistant and are common practice in the optical

In this work, we investigate the spin symmetry of a hypernuclei by focusing on the \(\Lambda\)-hypernuclei. In this case, we solve the Dirac equation with scalar and vector Killingbeck potential and obtain energy eigenvalues and spinor wave functions for s-wave bound states by using the analytical method. Then, for some hypernuclei, their binding energy is reproduced. The results are in good agreement

Wave characteristics of solitons with damped structures in a four-component plasma fluid having positive and negative ions, nonthermal distributed positrons and electrons have been studied. The damped Kadomtsev–Petviashvili (DKP) equation has been obtained in a small amplitude limit. The nonlinear criticality of DKP is examined for related Earth’s ionosphere plasma parameters. The effects of the positron

In this paper, the bound states of pentaquark systems are studied by solving the Schrodinger equation containing Van der Waals potential via Nikiforov–Uvarov method. The binding energies, wave functions and the masses of heavy pentaquarks are calculated. The results are in agreement with the existing ones in the literature.

In this study, second-grade fluid is taken into account in order to examine its rotating behavior with heat and mass transfer effects. The analysis is carried out between two parallel plates. The study of heat and mass transfer is accomplished by taking the effects of non-constant diffusivity, conductivity and viscosity. A chemical reaction is taken in the form of activation energy. Moreover, it is

High-density polyethylene (HDPE) is irradiated to moderate gamma doses 10, 20, 30, 40 and 50 kGy to carry out the study of change in its states. It is conducted by measuring resistivity and capacitance due to scissoring of chains; hence, immergence of various functional groups in the bulk of samples is irradiated to three doses 10, 30 and 40 kGy. Enhanced resistivity is found to follow sequential change

The structural, electronic and mechanical properties of AgIn1−XGaXS2 (X = 0, 0.25, 0.50, 0.75, 1) chalcogenides are investigated. The crystal structure of ternary semiconductors is the chalcopyrite structure with space group \({\text{I}}\bar{4}2{\text{d}}\). In this work, first principles calculations are carried out based on density functional theory within the local density approximation to analyze

The present study was conducted to investigate the optical constants of copper (Cu)-doped zinc oxide (ZnO) films annealed at different temperatures. The absorption coefficient of the films increased by changing the annealing temperature. The lattice dielectric constant \( \varepsilon_{L} \), concentration of the free-charge carriers, plasma frequency, Spitzer–Fan model, and the waste heat of electrical