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Analytical solution of the steady-state atmospheric fractional diffusion equation in a finite domain Pramana (IF 1.688) Pub Date : 2021-01-02 Tankou Tagne Alain Sylvain, Ele Abiama Patrice, Ema’a Ema’a Jean Marie, Owono Ateba Pierre, Ben-Bolie Germain Hubert
In this work, an analytical solution for the steady-state fractional advection-diffusion equation was investigated to simulate the dispersion of air pollutants in a finite media. The authors propose a method that uses classic integral transform technique (CITT) to solve the transformed problem with a fractional derivative, resulting in a more general solution. We compare the solutions with data from
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A geometric look at the objective gravitational wave function reduction Pramana (IF 1.688) Pub Date : 2020-11-24 Faramarz Rahmani, Mehdi Golshani, Ghadir Jafari
There is a famous criterion for objective wave function reduction which is derived by using the Shrödinger–Newton equation [L Diosi, Phys. Lett. A 105(4–5), 199 (1984)]. In this regard, a critical mass for the transition from quantum world to the classical world is determined for a particle or an object. In this paper, we shall derive that criterion by using the concept of Bohmian trajectories. This
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Dynamical behaviour of fractional-order finance system Pramana (IF 1.688) Pub Date : 2020-11-24 Muhammad Farman, Ali Akgül, Muhammad Umer Saleem, Sumaiyah Imtiaz, Aqeel Ahmad
In this paper, we developed the fractional-order finance system transmission model. The main objective of this paper is to construct and evaluate a fractional derivative to track the shape of the dynamic chaotic financial system of fractional order. The numerical solution for fractional-order financial system is determined using the Atangana–Baleanu–Caputo (ABC) and Caputo derivatives. Picard–Lindelof’s
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Exact solutions of a quantum system placed in a Kratzer potential and under a uniform magnetic field Pramana (IF 1.688) Pub Date : 2020-11-18 F Maiz, Moteb M Alqahtani
We propose Whittaker function approach as a theoretical method for finding exact solutions of a quantum mechanical system placed in the Kratzer potential. We then show that the effect of an external uniform magnetic field on this system can be satisfactorily determined using variational method. By following the one-step treatment suggested in this study, we increase the reliability and the accuracy
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Predictions on structural, electronic, magnetic and thermal properties of new Heusler alloys Cr $$_{{{2}}}$$ 2 NbSi $$_{{1-x}}$$ 1 - x Ge $$_{{x }}$$ x from first-principles calculations Pramana (IF 1.688) Pub Date : 2020-11-11 I Asfour
In this study, by using full-potential linearised augmented plane wave (FP-LAPW) method with the generalised gradient approximation (GGA) based on density functional theory (DFT), the structural, electronic, elastic and magnetic properties of the Heusler alloys Cr\(_{\mathrm {2}}\)NbSi\(_{{1-x}}\)Ge\(_{x}\) have been evaluated. The AlCu\(_{\mathrm {2}}\)Mnl-type structure is more stable than the CuHg\(_{\mathrm
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Using a Lindbladian approach to model decoherence in two coupled nuclear spins via correlated phase damping and amplitude damping noise channels Pramana (IF 1.688) Pub Date : 2020-11-10 Harpreet Singh, Arvind, Kavita Dorai
In this work, we studied the relaxation dynamics of coherences of different orders present in a system of two coupled nuclear spins. We used a previously designed model for intrinsic noise present in such systems which considers the Lindblad master equation for Markovian relaxation. We experimentally created zero-, single- and double-quantum coherences in several two-spin systems and performed a complete
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Two bursting patterns induced by system solutions approaching infinity in a modified Rayleigh–Duffing oscillator Pramana (IF 1.688) Pub Date : 2020-11-05 Xindong Ma, Xiujing Han, Wen’an Jiang, Qinsheng Bi
In this paper, the mechanism of system solutions approaching infinity is explored based on a modified Rayleigh–Duffing oscillator with two slow-varying periodic excitations. System solutions approaching infinity is a new novel route to bursting oscillation, and are not reported yet. The system can be separated into a fast subsystem and a slow subsystem according to the slow–fast analysis method. We
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Fast transverse instability due to RF cavity impedance in the ILSF storage ring Pramana (IF 1.688) Pub Date : 2020-11-03 S Massoudi, S Aghaei, M Amniat-talab, J Rahighi
In this paper, the single bunch fast transverse instabilities of the electron beam in the ILSF storage ring due to the RF cavity impedance are investigated. We consider Satoh’s formalism (that studied mode coupling instabilities based on the Vlasov equation) and Lindberg’s formalisms (that studied mode coupling instabilities based on the Fokker–Planck equation). The Lindberg formalisms are rewritten
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Effect of magnetic field on the mixed convection $$\hbox {Fe}_{3}\hbox {O}_{{{4}}}/\hbox {water}$$ Fe 3 O 4 / water ferrofluid flow in a horizontal porous channel Pramana (IF 1.688) Pub Date : 2020-10-29 Amira Jarray, Zouhaier Mehrez, Afif El Cafsi
The effect of an external magnetic field on the mixed convection \(\hbox {Fe}_{{3}}\hbox {O}_{{4}}/\)water ferrofluid flow in a horizontal porous channel was studied numerically. The governing equations using the Darcy–Brinkman–Forchheimer formulation were solved by employing the finite volume method. The computations were carried out for a range of volume fractions of nanoparticles \(0\le \varphi
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An iteration algorithm for the time-independent fractional Schrödinger equation with Coulomb potential Pramana (IF 1.688) Pub Date : 2020-10-29 Marwan Al-Raeei, Moustafa Sayem El-Daher
A numerical formula is derived which gives solutions of the fractional Schrödinger equation in time-independent form in the case of Coulomb potential using Riemann–Liouville definition of the fractional derivative and the quadrature methods. The formula is applied for electron in the nucleus field for multiple values of fractional parameter of the space-dependent fractional Schrödinger equation and
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Non-linear Rayleigh–Bénard magnetoconvection in temperature-sensitive Newtonian liquids with heat source Pramana (IF 1.688) Pub Date : 2020-10-28 A S Aruna
The present paper aims at weak non-linear stability analysis followed by linear analysis of finite-amplitude Rayleigh–Benard magnetoconvection problem in an electrically conducting Newtonian liquid with heat source/sink. It is showed that the internal Rayleigh number, thermorheological parameter and Chandrasekhar number influence the onset of stationary convection and Nusselt number. The generalised
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Compact and strong window core steering magnets with homogeneous dipole field Pramana (IF 1.688) Pub Date : 2020-10-27 Bhaskar Biswas
A typical axially compact, square window core steering magnet has a very small 2D good field region (GFR) of 18% of the iron core aperture. It is weak with 85% of its dipole in the fringes. Increasing the current fed area (coil) to increase the dipole strength lowers the good field zone. Some novel and simple coil shapes can expand their 2D/3D GFR to 94/40% of the iron aperture. They are axially compact
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The neutron halo structure of $$^{14}\hbox {B}$$ 14 B , $$^{22}\hbox {N}$$ 22 N , $$^{23}\hbox {O}$$ 23 O and $$^{24}\hbox {F}$$ 24 F nuclei studied via the generalised Woods–Saxon potential Pramana (IF 1.688) Pub Date : 2020-10-24 Ahmed N Abdullah
The radial wave functions of the generalised Woods–Saxon (GWS) potential within the two-body model of \(\left( \mathrm {Core}+n \right) \) have been used to study the ground-state density distributions of protons, neutrons and matter and the associated root mean square (rms) radii of neutron-rich \(^{\mathrm {14}}\hbox {B}\), \(^{\mathrm {22}}\hbox {N}\), \(^{\mathrm {23}}\hbox {O}\) and \(^{\mathrm
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State feedback control and observer-based adaptive synchronisation of chaos in a memristive Murali–Lakshmanan–Chua circuit Pramana (IF 1.688) Pub Date : 2020-10-17 A Ishaq Ahamed, M Lakshmanan
In this paper we report the control and synchronisation of chaos in a memristive Murali–Lakshmanan–Chua (MLC) circuit. This circuit, introduced by the present authors in 2013, is basically a non-smooth system having two discontinuity boundaries by virtue of it having a flux-controlled active memristor as its nonlinear element. While the control of chaos has been effected using state feedback techniques
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Contributory effect of diffusive heat conduction and Brownian motion on thermal conductivity enhancement of nanofluids Pramana (IF 1.688) Pub Date : 2020-10-15 Sayantan Mukherjee, Purna Chandra Mishra, Paritosh Chaudhuri, Shanta Chakraborty
The effect of diffusive heat conduction and Brownian motion on the enhancement of thermal conductivity in nanofluids is presented here.\({\hbox {Al}}_{2} {\hbox {O}}_{3}\) and \({\hbox {TiO}}_{2}\) nanofluids were prepared at four different wt. fractions of 1%, 0.5%, 0.1% and 0.05% and their thermal conductivity values were measured over temperatures ranging from 25 to \(55^{\circ }\hbox {C}\) for
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Influence of excluded volume interactions on the dynamics of dendrimer and star polymers in layered random flow Pramana (IF 1.688) Pub Date : 2020-10-15 Neha, Divya Katyal, Rama Kant
The influence of excluded volume interactions (EVIs) governs the dynamics of branched polymeric structures. Therefore, we developed a theory with the inclusion of ubiquitous EVIs on average square displacement (ASD) of the centre of mass in layered random flow (LRF). The mean-field approach is used to account for effective EVIs between non-bonded monomers of generalised Gaussian structures. The effect
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Quasi-exact and asymptotic iterative solutions of Dirac equation in the presence of some scalar potentials Pramana (IF 1.688) Pub Date : 2020-10-15 A Chenaghlou, S Aghaei, R Mokhtari
In this paper, the Dirac equation in the presence of some scalar potentials based on sl(2) Lie algebra is solved by quasi-exact solvability theory. The configuration of the classes III and VI potentials in the Turbiner’s classification is constructed. Then, the Bethe ansatz equations are calculated so that the energy eigenvalues and eigenfunctions are obtained. Also, we study the problem by using asymptotic
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Some Bianchi I dark energy models in Brans–Dicke theory Pramana (IF 1.688) Pub Date : 2020-10-13 G P Singh, Ashwini R Lalke, Nikhil Hulke
The present article deals with the study of interacting and non-interacting dark energy (DE) and dark matter (DM) in the spatially homogeneous and anisotropic Bianchi I space–time within the framework of Brans–Dicke (BD) scalar–tensor theory of gravitation. As the set of field equations is not closed, exact solutions are obtained using power-law relation and assuming a linearly varying deceleration
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Energy deposition of heavy-ion beams in neutronless fusion reaction Pramana (IF 1.688) Pub Date : 2020-10-13 R Sotodeheian, M Mahdavi
Recent advances in laser-plasma accelerators have made possible the production of high-power beams with very low divergence. In this paper, the carbon heavy-ion beam was used to provide optimal conditions for the ignition of P–\(^{\mathrm {11}}\)B clean fuel pellets using the Deira-4 simulation code. The calculations showed that generating maximum ion heating of about 140 keV requires a laser with
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Approximate technique for solving fractional variational problems Pramana (IF 1.688) Pub Date : 2020-10-13 Haleh Tajadodi, Nematollah Kadkhoda, Hossein Jafari, Mustafa Inc
The purpose of this paper is to suggest a numerical technique to solve fractional variational problems (FVPs). These problems are based on Caputo fractional derivatives. Rayleigh–Ritz method is used in this technique. First we approximate the objective function by the trapezoidal rule. Then, the unknown function is expanded in terms of the Bernstein polynomials. By this method, a system of algebraic
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Effects of aberrations on the point spread function and the two-point resolution with versatile apodization pupils Pramana (IF 1.688) Pub Date : 2020-10-09 Andra Naresh Kumar Reddy, Mahdieh Hashemi, Dasari Karuna Sagar
In this work, efficient amplitude-apodization pupils have been presented for tailoring the point spread function (PSF), which results in a decreased full-width at half-maximum (FWHM) and suppressed sidelobes. Comparison of PSF intensity profiles for both the unapodized and apodized cases have been reported. By analysing the resulting PSFs, the well-known effects induced by monochromatic aberrations
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On the interaction between tripod-type four-level atom and one-mode field in the presence of a classical homogeneous gravitational field Pramana (IF 1.688) Pub Date : 2020-10-09 Ahmed Salah, L E Thabet, T M El-Shahat, N H Abd El-Wahab
In this paper, we investigate the effects of gravitational field on the dynamical behaviour of nonlinear atom–field interaction. We consider a moving tripod-type four-level atom interacting with a single mode field in the presence of a classical homogeneous gravitational field. The analytical solution of the model is calculated by using the Schrödinger equation for a coherent electromagnetic field
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The Fredholm determinant for Hulthén-distorted non-local separable potential: Application to $$ \alpha {-}\alpha $$ α - α elastic scattering Pramana (IF 1.688) Pub Date : 2020-10-09 U Laha, A K Behera, M Majumder, J Bhoi
Exact analytical expression of the Fredholm determinant with outgoing wave boundary condition for motion in Hulthén-distorted non-local separable potential is constructed and expressed in the maximum reduced form. Using boundary conditions (regular and irregular), two approximate energy-dependent interactions corresponding to the parent non-local potential are also constructed. The phase shifts for
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Effect of point/line heat source and Hall current on free convective flow between two vertical walls Pramana (IF 1.688) Pub Date : 2020-10-07 Naveen Dwivedi, Ashok Kumar Singh
The influence of a point heat source and Hall current on the laminar hydromagnetic free convective flow of an incompressible and electrically conducting viscous liquid between two vertical walls has been studied. A wavelet function is utilised to mathematically formulate the point or line heat source. The incidental equations on the flow have been processed subject to the Boussinesq approximation.
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On the analytic representation of Newtonian systems Pramana (IF 1.688) Pub Date : 2020-09-21 Benoy Talukdar, Supriya Chatterjee, Sekh Golam Ali
We show that the theory of self-adjoint differential equations can be used to provide a satisfactory solution of the inverse variational problem in classical mechanics. A Newtonian equation, when transformed to the self-adjoint form, allows one to find an appropriate Lagrangian representation (direct analytic representation) for it. On the other hand, the same Newtonian equation in conjunction with
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A generalised short pulse equation: Darboux transformation and exact solutions Pramana (IF 1.688) Pub Date : 2020-09-21 Chendi Zhu, Lihua Wu
We construct infinitely many conservation laws of the generalised short pulse equation with the help of its Lax pairs. By a reciprocal transformation, the generalised short pulse equation was transformed to the first negative flow of Sawada–Kotera hierarchy. On the basis of Darboux and reciprocal transformations, we obtain some exact solutions of the generalised short pulse equation.
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Optical solitons for complex Ginzburg–Landau model with Kerr, quadratic–cubic and parabolic law nonlinearities in nonlinear optics by the $$\hbox {exp}(-\Phi (\zeta ))$$ exp ( - Φ ( ζ ) ) expansion method Pramana (IF 1.688) Pub Date : 2020-09-21 M K Elboree
The optical solitons for the complex Ginzburg–Landau model with Kerr law, quadratic–cubic law and parabolic law are obtained via the \(\hbox {exp}(-\Phi (\zeta ))\) expansion method. Many abundant solutions such as complex dark-singular, complex periodic-singular and plane-wave solutions are derived for this model. These complex solutions are useful for understanding the physical properties for this
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Integrability and exact solutions of deformed fifth-order Korteweg–de Vries equation Pramana (IF 1.688) Pub Date : 2020-09-21 S Suresh Kumar, R Sahadevan
We consider a deformed fifth-order Korteweg–de Vries (D5oKdV) equation and investigated its integrability and group theoretical aspects. By extending the well-known Lax pair technique, we show that the D5oKdV equation admits a Lax representation provided that the deformed function satisfies certain differential constraint. It is observed that the D5oKdV equation admits the same differential constraint
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Exact solutions of time-fractional generalised Burgers–Fisher equation using generalised Kudryashov method Pramana (IF 1.688) Pub Date : 2020-09-05 Ramya Selvaraj; Swaminathan Venkatraman; Durga Devi Ashok; Krishnakumar Krishnaraja
This study deals with the generalised Kudryashov method (GKM) for the time-fractional generalised Burgers–Fisher equation (TF-GBF). Using the transformation of travelling wave, the TF-GBF is transformed into a non-linear ordinary differential equation (NLODE). Later, GKM has been applied in the resultant equation which is a novel technique to obtain exact solutions. These exact solutions are plotted
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Empirical formula for beta-particle-induced bremsstrahlung yields Pramana (IF 1.688) Pub Date : 2020-09-05 H C Manjunatha
We have measured the \(\beta \)-particle-induced bremsstrahlung energy yield and photon yield in the energy range 0.1668–2.274 MeV using beta sources such as \(^{\mathrm {35}}\hbox {S}\) (0.1668), \(^{\mathrm {99}}\hbox {Tc}\) (0.293), \(^{\mathrm {147}}\hbox {Pm}\) (0.225), \(^{\mathrm {90}}\hbox {Sr}\) (0.5462), \(^{\mathrm {204}}\hbox {Tl}\) (0.76), \(^{\mathrm {91}}\hbox {Y}\) (1.5), \(^{\mathrm
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Bulk viscous accelerating Universe in f ( R , T ) theory of gravity Pramana (IF 1.688) Pub Date : 2020-09-04 R Prasad; Lalit Kumar Gupta; G K Goswami; Anil Kumar Yadav
In this paper, we propose that the late-time acceleration of the Universe is due to bulk viscous fluid and trace of energy–momentum tensor T in f(R, T) theory of gravity. We assume that \(f(R,T) = f(R) + 2f(T)\) with \(f(R) = R\) and \(f(T) = \lambda T\) where \(\lambda \) is a constant, R and T are the Ricci scalar and trace of energy–momentum tensor. First, we obtain an exact solution of the bulk
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On the solitary wave solutions of modified Benjamin–Bona–Mahony equation for unidirectional propagation of long waves Pramana (IF 1.688) Pub Date : 2020-09-03 A K Gupta; J Hazarika
In this article, generalised Kudryashov technique has been implemented to construct new soliton solutions of modified Benjamin–Bona–Mahony (mBBM) equation. Also, the optimal homotopy asymptotic method (OHAM) has been employed to estimate the numerical solution. The solutions thus acquired by the above methods are illustrated graphically. The techniques considered here are efficacious, plausible and
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Dark matter through the quark vector current portal Pramana (IF 1.688) Pub Date : 2020-08-29 Dillon Berger; Arvind Rajaraman; Jason Kumar
We consider models of light dark matter coupled to quarks through a vector current interaction. For low energies, these models must be treated through the effective couplings to mesons, which are implemented here through the chiral Lagrangian. We find the signals of dark matter annihilation and decay to the light mesons, and find the expected photon spectrum from the decay of the hadrons. We compare
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A modified chaotic oscillator with megastability and variable boosting and its synchronisation using contraction theory-based control which is better than backstepping and nonlinear active control Pramana (IF 1.688) Pub Date : 2020-08-28 J P Singh; S Jafari; A J M Khalaf; V-T Pham; B K Roy
This paper reports a modified 2D periodically forced oscillator. Numerical simulation results using the phase portrait and Lyapunov exponents’ spectrum say that the proposed oscillator depicts megastability. Offset boosting in the new system is shown using the variable boostable phenomenon. Very limited research is available on such type of oscillator. Further, in this paper, a controller based on
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Terahertz broadband metamaterial absorber enabled by $$\hbox {SiO}_{{{2}}}$$ SiO 2 , polyimide and PET dielectric substrates Pramana (IF 1.688) Pub Date : 2020-08-27 A Elakkiya; S Radha; B S Sreeja; E Manikandan
A broadband polarisation-insensitive terahertz (THz) metamaterial absorber (MMA) is presented in this paper. The MMA consists of a simple planar structure as a unit cell and an optically transparent indium tin oxide (ITO) ground plane, both are separated by a \(50\, \mu \hbox {m}\) dielectric substrate. We designed three combinations of MMA here, which are ITO–polyimide–ITO, ITO–polyethylene terephthalate
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Power law memory of natural convection flow of hybrid nanofluids with constant proportional Caputo fractional derivative due to pressure gradient Pramana (IF 1.688) Pub Date : 2020-08-27 Rizwan Ali; Ali Akgül; Muhammad Imran Asjad
In this work, influence of hybrid nanofluids on heat transfer flow of a viscous fluid due to pressure gradient is discussed with innovative constant proportional Caputo fractional derivative. For this purpose, we consider an infinite vertical wall which is exponentially moving in the x-direction with variable temperature. Nanosized particles of Cu and \(\hbox {Al}_{2}\hbox {O}_{3}\) are suspended in
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Observation of Fano resonance in silver nanocube–nanosphere dimer Pramana (IF 1.688) Pub Date : 2020-08-20 Avijit Das; Arik Ahmed; Md Mehedi Hasan
In this paper, we perform a theoretical investigation of the plasmon coupling in silver (Ag) nanocube–nanosphere dimer using finite difference time domain (FDTD) technique. Due to plasmonic Fano resonance, we observe a pronounced dip in the absorption spectrum, which is induced by the destructive interference between the bright dipole mode from the Ag nanocube and the dark quadrupole mode from the
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Viscous Ricci dark energy model with matter creation: Exact solution and observational tests Pramana (IF 1.688) Pub Date : 2020-08-20 Ajay Kumar; C P Singh
In this paper, the dissipative mechanism (bulk viscosity and matter creation) is introduced to describe the effects of cosmic non-perfect fluid on the Ricci dark energy (RDE) model. We consider matter creation and bulk viscosity as two independent irreversible processes. Assuming suitable forms of the bulk viscous coefficient and matter creation rate, we find the exact solution of the field equations
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Image processing of Ramses II statue using speckle photography modulated by a new Hamming linear aperture Pramana (IF 1.688) Pub Date : 2020-08-16 A M Hamed
In this paper, a new concentric Hamming linear aperture is suggested. The point spread function (PSF) is computed for concentric Hamming linear aperture and it is compared with the corresponding circular, conventional Hamming and obstructed Hamming apertures. In addition, the autocorrelation corresponding to the aperture under consideration is computed and plotted. Application of the Hamming linear
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Bipartite entanglement in Auger ionisation of $${\text{ N }}_{2}$$ N 2 Pramana (IF 1.688) Pub Date : 2020-08-16 S Sen; M Chakraborty
Quantum entanglement and its paradoxical properties are of paramount importance in quantum information theory. In recent years, there has been an increasing interest in the studies of high-dimensional quantum states and their impact on quantum communication as it can encode and process more data. Photonic entanglement is usually an evanescent property as it is destroyed easily by its interaction with
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Effect of suction/blowing on heat-absorbing unsteady radiative Casson fluid past a semi-infinite flat plate with conjugate heating and inclined magnetic field Pramana (IF 1.688) Pub Date : 2020-08-16 R Mahato; M Das
This article studies the effect of suction/blowing, inclined magnetic field, and chemical reaction on heat-absorbing unsteady radiative Casson fluid past a semi-infinite flat plate in porous medium incorporating the oscillatory plate movement as a linear combination of ‘cosine’ and ‘sine’ functions in time. Further, the mass and heat transfer characteristics are examined under the influence of conjugate
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Dynamic frequency analysis of stress–strain-dependent reversibly deformable broadband RF antenna over unevenly made elastomeric substrate Pramana (IF 1.688) Pub Date : 2020-08-13 S Deepa Nivethika; B S Sreeja; E Manikandan; S Radha; M Senthilpandian
This paper presents the design and development of stretchable and deformable broadband antenna using low-cost silicone rubber-based dielectric substrate. A slot is introduced in the substrate to improve the stretchable behaviour. The dielectric properties of the substrate are measured using suspended ring resonator method. The proposed antenna uses silver elastomeric Lycra fabric as the conductive
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A new combined soliton solution of the modified Korteweg–de Vries equation Pramana (IF 1.688) Pub Date : 2020-08-13 Jianping Wu
In this paper, the Riemann–Hilbert problem of the modified Korteweg–de Vries (mKdV) equation is studied, from which a new combined soliton solution is obtained. In addition, to illustrate the dynamics of the new combined soliton solution, an algebra technique is developed to demonstrate the soliton interactions using Mathematica symbolic computations. The proposed method is effective in deriving and
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Density functional study on structural and optoelectronic properties of cubic $$\hbox {Mg}_{x}\hbox {Zn}_{1-x}\hbox {S}_{y}\hbox {Se}_{1-y}$$ Mg x Zn 1 - x S y Se 1 - y semiconductor quaternary alloys Pramana (IF 1.688) Pub Date : 2020-08-13 Debankita Ghosh; Sayantika Chanda; Bimal Debnath; Manish Debbarma; Rahul Bhattacharjee; Surya Chattopadhyaya
In the case of technologically important quaternary alloys, structural and optoelectronic properties have been calculated with density functional theory (DFT)-based full-potential linearised augmented plane-wave (FP-LAPW) approach. The Perdew–Burke–Ernzerhof generalised gradient approximation (PBE-GGA) for structural properties and both the modified-Becke–Johnson (mBJ) and Engel and Vosko GGA (EV-GGA)
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Equation of state of PNJL model under the influence of thermal mass and magnetic field Pramana (IF 1.688) Pub Date : 2020-08-13 Anju Dahiya; S Somorendro Singh
We present analytical results of the equation of state (EOS) described by a model of thermal quark mass and magnetic potential term introduced in Polyakov–Nambu–Jona–Lasinio (PNJL) model for two-flavour quarks. Under the influence of thermal quark mass and magnetic field term in the potential, the calculated results of EOS using the model are enhanced in a good pattern up to the temperature \(T=2.2T_{c}
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Mechanical conversion of the gravitational Einstein’s constant $$\kappa $$ κ Pramana (IF 1.688) Pub Date : 2020-08-13 Izabel David
This study attempts to answer the question of what space is made of and explores in this objective the analogy between the Einstein’s gravitational geometrical theory in one- and two-dimensional linear deformations and a possible space material based on strain measures done on the Ligo or Virgo interferometers. It draws an analogy between the Einstein’s gravitational constant \(\kappa \) and the Young’s
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An efficient algorithm for inferring functional connectivity between the drive and the noisy response chaotic oscillators with significant frequency mismatch Pramana (IF 1.688) Pub Date : 2020-08-13 Kazimieras Pukenas
In this study, we present a new method for assessing the functional connectivity between the drive and the noisy response chaotic oscillators with significant frequency mismatch. This method is based on the footprint of the drive oscillator on the response oscillator. Specifically, we calculate the magnitude squared coherence between the intrinsic frequency of the drive oscillator and the oscillation
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Hadron energy estimation from atmospheric neutrino events Pramana (IF 1.688) Pub Date : 2020-08-08 M Nizam; S Uma Sankar
The iron calorimeter (ICAL) at India-based neutrino observatory (INO) is designed to mainly observe the muons produced in the charged current interactions of atmospheric muon neutrinos and antineutrinos. The track of the muon is reconstructed using the hits they produce in the detector. From this track, the charge, the energy and the direction of the muon are estimated, which are used to do oscillation
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Lie symmetry reductions and dynamics of soliton solutions of (2 $$+$$ + 1)-dimensional Pavlov equation Pramana (IF 1.688) Pub Date : 2020-08-04 Sachin Kumar; Setu Rani
In the present article, Lie group of point transformations method is successfully applied to study the invariance properties of the \((2+1)\)-dimensional Pavlov equation. Applying the Lie symmetry method, we strictly obtain the infinitesimals, vector fields, commutation relation and several interesting symmetry reductions of the equation. The explicit exact solutions are derived under some limiting
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Effect of impurities and defect in thermal conductivity of lead sulphide Pramana (IF 1.688) Pub Date : 2020-08-04 Richa Saini
The phenomenon of heat conduction is important in semiconductor devices. This property is investigated on the basis of modified Callway model. The formalism was carried out using Hamiltonian, phonon Green’s function and equation of motion techniques for various scattering events. It was found that every scattering mechanism is independent of each other and does not affect the others. The thermal conductivity
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Electrochemical detection of sotalol on a magnetographite-epoxy electrode using magnetite nanoparticles Pramana (IF 1.688) Pub Date : 2020-07-30 Ana Isa Pérez; Elsa M Materón; Maria Valnice Boldrin Zanoni; Josino Costa Moreira; Percio Augusto Mardini Farias; FErnando Gomes DE Souza
Sotalol hydrochloride (STHCl) is a cardiovascular agent, specifically an antiarrhythmic and beta-blocker, that can be used regularly for an extended period. However, it may have side effects, such as weakness and slow heart rate (bradycardia). Currently, techniques such as capillary zone electrophoresis and high-performance liquid chromatography have been widely used for the determination of sotalol
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Nonlinear stability analysis of coupled azimuthal interfaces between three rotating magnetic fluids Pramana (IF 1.688) Pub Date : 2020-07-30 Galal M Moatimid; Marwa H Zekry
The current work deals with the nonlinear azimuthal stability analysis of coupled interfaces between three magnetic fluids. The considered system consists of three incompressible rotating magnetic fluids throughout the porous media. Additionally, the system is pervaded by a uniform azimuthal magnetic field. Therefore, for simplicity, the problem is considered in a planar configuration. The adopted
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Thermal entanglement and teleportation via thermally atomic entangled state in cavity QED Pramana (IF 1.688) Pub Date : 2020-07-28 S Mirzaei
In this article, we study thermal entanglement between two-coupled two-level atoms interacting with a single-mode cavity field. The cavity mode is assumed to be initially in the vacuum state and the detuning parameter is large. The thermal entanglement in this two-qubit system is quantified in terms of the concurrence, as a proper measure for two-qubit mixed states. We investigate how the thermal entanglement
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Numerical analysis of ultrathin Cu(In,Ga)Se $$_{2}$$ 2 solar cells with Zn(O,S) buffer layer Pramana (IF 1.688) Pub Date : 2020-07-24 G L MBOPDA TCHEUM; A TEYOU NGOUPO; S OUÉDRAOGO; N GUIRDJEBAYE; J M B NDJAKA
We performed an investigation on the behaviour of the electrical parameters of ultrathin Cu(In,Ga)Se\(_{\mathrm {2}}\) (CIGS) solar cells buffered with Zn(O,S). Using one-dimensional simulations and by defining a new structure, we achieved a significant reduction of the absorber and the buffer layers to evaluate the changes in the cell’s performance. The simulation results revealed that a good optimisation
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Studies on the characteristics of $$\hbox {TiO}_2$$ TiO 2 photoanode and flavanol pigment as a sensitiser for DSSC applications Pramana (IF 1.688) Pub Date : 2020-07-24 S Vedavarshni; T Raguram; K S Rajni
In the present work, dye-sensitised solar cell (DSSC) is fabricated using natural dye (Tecoma Stans)-sensitised \(\hbox {TiO}_{\mathrm {2\, }}\) as the photoanode, platinum as the counter electrode and lithium iodide and iodine as the electrolyte. Initially, \(\hbox {TiO}_{\mathrm {2\, }}\) nanoparticles are synthesised by the sol–gel technique using glacial acetic acid as the hydrolysing agent. The
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Amorphisation of boron carbide under gamma irradiation Pramana (IF 1.688) Pub Date : 2020-07-21 Matlab N Mirzayev; Ertuğrul Demir; Khagani F Mammadov; Vladimir A Sukratov; Sakin H Jabarov; Saphina Biira; Elmar B Asgerov; Bekhzodjon A Abdurakhimov; A Beril Tuğrul
Boron carbide (\(\hbox {B}_{\mathrm {4}}\hbox {C}\)) has been widely used in nuclear reactors and nuclear applications. In this work, the high-purity (99.9%) \(\hbox {B}_{\mathrm {4}}\hbox {C}\) samples were irradiated using a gamma source (\(^{\mathrm {60}}\hbox {Co}\)) with a dose rate (D) of 0.27 Gy/s at different gamma irradiation doses at room temperature. Phase and microstructural characterisation
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Importance of self-shielding in mass measurements using $$\gamma $$ γ -ray spectroscopy Pramana (IF 1.688) Pub Date : 2020-07-20 Jesse D Norris; Shikha Prasad
Due to the exponential attenuation of photons in materials, thick samples will attenuate a large portion of photons. This is a source of error in methods such as neutron activation analysis, which use gamma spectroscopy to characterise a radioactive source. A method is developed to quantify the magnitude of self-shielding with the help of MCNP6. Then the mass of an unknown sample is determined by comparing
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Soret and Dufour effects on MHD boundary layer flow of non-Newtonian Carreau fluid with mixed convective heat and mass transfer over a moving vertical plate Pramana (IF 1.688) Pub Date : 2020-07-16 Anil Kumar Gautam; Ajeet Kumar Verma; Krishnendu Bhattacharyya; Astick Banerjee
In this analysis, the mixed convection boundary layer MHD flow of non-Newtonian Carreau fluid subjected to Soret and Dufour effects over a moving vertical plate is studied. The governing flow equations are converted into a set of non-linear ordinary differential equations using suitable transformations. For numerical computations, bvp4c in MATLAB package is used to solve the resulting equations. Impacts
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Ab-initio study of ordered III–V antimony-based semiconductor alloys $$\mathbf{GaP }_{1-x}{} \mathbf{Sb} _{x} \mathbf{and} AlP _{1-x}{} \mathbf{Sb} _{x}$$ GaP 1 - x Sb x and A l P 1 - x Sb x Pramana (IF 1.688) Pub Date : 2020-07-16 F Annane; H Meradji; S Ghemid; H Bendjeddou; F El Haj Hassan; Vipul Srivastava; R Khenata
In this work, we have investigated the structural, electronic and thermodynamic properties of GaP\(_{1-x}\)Sb\(_{x}\) and AlP\(_{1-x}\)Sb\(_{x}\) ternary alloys for a number of ordered structures and compositions in a series of first-principles calculations within the density functional theory, using full potential-linearised augmented plane-wave (FP-LAPW) method, as implemented in the WIEN2k code
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Invariant subspaces and exact solutions for some types of scalar and coupled time-space fractional diffusion equations Pramana (IF 1.688) Pub Date : 2020-07-16 P Prakash
We explain how the invariant subspace method can be extended to a scalar and coupled system of time-space fractional partial differential equations. The effectiveness and applicability of the method have been illustrated using time-space (i) fractional diffusion-convection equation, (ii) fractional reaction-diffusion equation, (iii) fractional diffusion equation with source term, (iv) two-coupled system
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