OICC PRESS Effect of negative oxygen ions on the characteristics of plasma in a cylindrical DC discharge Volume 7 (2013) Issue 1 2022 12 25 Effect of negative oxygen ions on the characteristics of plasma in a cylindrical DC discharge 10.1007/s40094-014-0122-z EN Farnaz Araghi Plasma Physics Research Center, Science and Research Branch, Islamic Azad University Davoud Dorranian Plasma Physics Research Centre, Science and Research Branch, Islamic Azad University, Tehran, Iran 0000-0001-8855-7425 Journal Article 2022 12 25 AbstractLangmuir probe measurements are performed in cylindrical dc glow discharge plasma. Plasma was generated in an evacuated glass tube, with circular plane disk electrodes. Measurements were carried out at different points along the axis of tube for different working pressures of pure argon and mixture of argon–oxygen gasses to obtain the plasma density and temperature as well as plasma and floating potentials. Variation of discharge potential as a function of discharge pressure for both plasmas is observed. It is shown that electron temperature, plasma potential, and floating potential in constant current mode and constant pressure are increased from cathode to anode on the axial points of the discharge tube, while electron density is decreased. To sustain the discharge process after adding oxygen to plasma, higher voltage is required since electrons are more energetic at lower density.

OICC PRESS Relativistic spin symmetry of the generalized Morse potential including tensor interaction Volume 7 (2013) Issue 1 2022 12 25 Relativistic spin symmetry of the generalized Morse potential including tensor interaction 10.1186/2251-7235-7-53 EN Akpan N. Ikot Theoretical Physics Group, Department of Physics, University of Uyo, Uyo, Nigeria 0000-0002-1078-262X Elham Maghsoodi Department of Basic Sciences, Shahrood Branch, Islamic Azad University Saber Zarrinkamar Department of Basic Sciences, Garmsar Branch, Islamic Azad University Hassan Hassanabadi Department of Basic Sciences, Shahrood Branch, Islamic Azad University Journal Article 2022 12 25 AbstractThe relativistic Dirac equation under spin symmetry is investigated for generalized Morse potential. We calculated the eigenvalues and the corresponding wave function by using the Nikiforov-Uvarov method. We also discussed two special cases: attractive radial and Deng-Fan potentials. We have also reported some numerical results and figures to show the effect of tensor interaction.

OICC PRESS Plasmon resonance coupling in cold overdense dissipative plasma Volume 7 (2013) Issue 1 2022 12 25 Plasmon resonance coupling in cold overdense dissipative plasma 10.1186/2251-7235-7-24 EN Journal Article 2022 12 25 AbstractIt has been shown that the overdense plasma in the resonance conditions can be totally transparent to the incident electromagnetic waves, due to the excitation of the surface modes or plasmons. This scenario requires excitation of a single surface mode which is provided by placing a dielectric layer in front of the incident wave. Here, it is shown that this procedure would be complete and more efficient by arranging the conditions to excite coupled surface modes, namely by placing two dielectrics on both sides of the plasma layer. The results show that in this case, the overdense plasma slab could poses high transmittance in spite of the presence of the dissipative effects. In addition, in this case, the resonance conditions can be achieved more easily and efficiently, and can be used for wider range of the overdense plasma widths.

OICC PRESS Classical information theoretic view of physical measurements and generalized uncertainty relations Volume 7 (2013) Issue 1 2022 12 25 Classical information theoretic view of physical measurements and generalized uncertainty relations 10.1186/2251-7235-7-28 EN Journal Article 2022 12 25 AbstractUncertainty relations are discussed in detail not only for free particles but also for bound states within the framework of classical information theory. Uncertainty relation for simultaneous measurements of two physical observables is defined in this framework for generalized dynamic systems governed by a Sturm-Liouville-type equation of motion. In the first step, the reduction of Kennard-Robertson type uncertainties because of boundary conditions with a mean square error is discussed quantitatively with reference to the information entropy. Several concrete examples of generalized uncertainty relations are given. Then, by considering disturbance effects, a universally valid uncertainty relation is investigated for the generalized equation of motion with a certain boundary condition. The necessary conditions for violation (reduction) of the Heisenberg-type uncertainty relation are discussed in detail. The reduction of the generalized uncertainty relation because of the boundary condition is discussed by reanalyzing experimental data for measured electron densities in a hydrogen molecule encapsulated in a fullerene C60 cage.

OICC PRESS Packet charge dynamic in thin polyethylene under high dc voltage Volume 7 (2013) Issue 1 2022 12 25 Packet charge dynamic in thin polyethylene under high dc voltage 10.1186/2251-7235-7-29 EN Journal Article 2022 12 25 AbstractIn this paper, we present a bipolar transport model in low-density polyethylene under high direct-current voltage in order to investigate the charge packet dynamic generated under high injection. These charge packets, observed by our model for the first time, have already been seen in some previous experimental works for a long time. Our model results show that applied electric field and sample thickness play important roles on the apparition of space charge packets.

OICC PRESS Luminescent properties of lanthanide dibenzoylmethide triethylammonium compounds Volume 7 (2013) Issue 1 2022 12 25 Luminescent properties of lanthanide dibenzoylmethide triethylammonium compounds 10.1186/2251-7235-7-30 EN Journal Article 2022 12 25 AbstractTriboluminescence (TL) is defined as the emission of cold light based on mechanical action. In 1999, Sage and Geddes used this property to design a sensor capable of discerning the location of impacts. By coating a structure with various triboluminescent materials, impacts to structures could be monitored with simple light detectors. However, the intensity of most materials is very low. Of the thousands of known triboluminescent materials, only a few can emit enough light to be seen in daylight. One of these materials is europium dibenzoylmethide triethylammonium (EuD4TEA). This material shows 206% of the TL yield compared to the more commonly known manganese-doped zinc sulfide. Due to the high TL yield of EuD4TEA, exploration of the lanthanide series compounds was attempted for different emission wavelengths. This will help to monitor the locations of impacts on structures. This paper will investigate the TL yields, TL decay times, and the spectra of various lanthanide dibenzoylmethide triethylammonium compounds.PACS78.60.Mq, 78.55.Bq, 71.20.Eh

OICC PRESS Propagation of magnetogasdynamic shock waves in a self-gravitating gas with exponentially varying density Volume 7 (2013) Issue 1 2022 12 25 Propagation of magnetogasdynamic shock waves in a self-gravitating gas with exponentially varying density 10.1186/2251-7235-7-15 EN Journal Article 2022 12 25 AbstractNon-similarity solutions are obtained for one-dimensional adiabatic flow behind a magnetogasdynamic spherical (or cylindrical) shock wave propagating in a self-gravitating perfect gas in the presence of a constant azimuthal magnetic field. The density of the gas is assumed to be varying and obeying an exponential law. The shock wave moves with variable velocity, and the total energy of the wave is non-constant and varies with time. The effects of variation of the Alfven-Mach number and time are obtained. It is investigated that the presence of gravitational field reduces the effects of the magnetic field. Also, the presence of gravitational field increases the compressibility of the medium, due to which it is compressed and therefore the distance between the inner contact surface and the shock surface is reduced. A comparison between the solutions in the cases of the gravitating and the non-gravitating medium with or without magnetic field is made. The solutions are applicable for arbitrary values of time.MSC76L05, 76W05

OICC PRESS Fractional action cosmology: some dark energy models in emergent, logamediate, and intermediate scenarios of the universe Volume 7 (2013) Issue 1 2022 12 25 Fractional action cosmology: some dark energy models in emergent, logamediate, and intermediate scenarios of the universe 10.1186/2251-7235-7-25 EN Journal Article 2022 12 25 AbstractIn the framework of fractional action cosmology, we have reconstructed the scalar potentials and scalar fields, namely, quintessence, phantom, tachyon, k-essence, Dirac-Born-Infeld-essence, hessence, dilaton field, and Yang-Mills field. To get more physical picture of the variation of the scalar field and potential with time, we express a scale factor in emergent, logamediate, and intermediate scenarios, under which the universe expands differently.PACS98.80.Cq, 95.36.+x

OICC PRESS Electrical conduction in nanoceramic PGT synthesised by high energy ball milling Volume 7 (2013) Issue 1 2022 12 25 Electrical conduction in nanoceramic PGT synthesised by high energy ball milling 10.1186/2251-7235-7-26 EN Journal Article 2022 12 25 AbstractNanocrystalline Pb1–3x/2GdxTiO3 (where x = 0.01) abbreviated as PGT has been synthesised by high energy ball milling at room temperature. X-ray analysis shows that single-phase tetragonal structure of nanocrystalline PGT was formed after 15-h milling. The average crystallite size was found to be 17 nm. The frequency-dependent AC conductivity of the PGT ceramic was studied in the range 100°C to 525°C. Complex impedance analysis suggested the dielectric relaxation to be of non-Debye type. The activation energy was found to be 1.04 ev. The mechanism of charge transport in nanocrystalline PGT was successfully explained by correlated hopping model.

OICC PRESS The impact of AsH3 overflow time and indium composition on the formation of self-assembled InxGa1 − xAs quantum dots studied by atomic force microscopy Volume 7 (2013) Issue 1 2022 12 25 The impact of AsH3 overflow time and indium composition on the formation of self-assembled InxGa1 − xAs quantum dots studied by atomic force microscopy 10.1186/2251-7235-7-27 EN Journal Article 2022 12 25 AbstractWe have performed atomic force microscopy to investigate the effect of various indium compositions and various AsH3 flow times during cooling on the formation of self-assembled InxGa1 − xAs quantum dots (QDs). The InxGa1 − xAs QDs were grown by metal-organic chemical vapour deposition using the Stranski-Krastanow (S-K) growth mode. The migration of group III species in the growth of InxGa1 − xAs QDs is influenced by the AsH3 flow during the cooling period due to the increasing surface population of the active arsenic species. It influences the size and density of the dots on the surface. For various indium compositions, an increase in InxGa1 − xAs QD density with increasing indium composition is observed. It indicates that the dot density depends on lattice parameters. The dot density is inversely proportional to surface diffusion (ρ ∝ R/D), with D = (2kT/h)/a2 exp(−ED/kT). In the growth of InxGa1 − xAs QDs using the S-K growth mode, the dots were formed on the surface as the effect of elastic strain relaxation due to the lattice mismatch. Increasing indium composition affects the lattice mismatch of the InxGa1 − xAs/GaAs QD system, which influences the dot formation on the surface. However, due to the stochastic nature of the nucleation of self-assembled growth, control of the spatial ordering of the QDs has proved to be extremely challenging.

OICC PRESS Effects of viscous dissipation on MHD natural convection flow along a vertical wavy surface Volume 7 (2013) Issue 1 2022 12 25 Effects of viscous dissipation on MHD natural convection flow along a vertical wavy surface 10.1186/2251-7235-7-31 EN Journal Article 2022 12 25 AbstractAn analysis is presented to investigate the influences of viscous dissipation on MHD natural convection flow along a uniformly heated vertical wavy surface. The governing equations are transformed into dimensionless non-similar equations using a set of suitable transformations and solved numerically by the implicit finite difference method known as the Keller box scheme. Numerical results for the velocity profiles, temperature profiles, skin friction coefficient, and the rate of heat transfers are shown graphically and in tabular form for different values of the selective set of parameters.

OICC PRESS Relativistic dynamics of electrons around impurities in high-density plasmas Volume 7 (2013) Issue 1 2022 12 25 Relativistic dynamics of electrons around impurities in high-density plasmas 10.1186/2251-7235-7-33 EN Journal Article 2022 12 25 AbstractIn this work, we focus our attention on the dynamic properties of relativistic electrons moving around an impurity in a plasma. This led us, in the first place, to compute the effective plasma potential (EPP) in which the electrons move. The EPP is built up as a sum of three contributions. These include the potential created by the impurity, the potential due to the ions assumed to form a uniform background of positive electric charges and the potential due to all the electrons. It turns out that the last potential depends on an integral of a function of the EPP in question. This then leads to a nonlinear integral equation where the EPP is the main quantity to compute. Thanks to the EPP, we derive the electron trajectories and compute their total electric field (microfield) at the impurity. According to different plasma conditions, two dynamical properties are then calculated: the time auto-correlation function of this microfield and the dielectric constant. These properties are calculated for both the relativistic case and non-relativistic (classical) case. The comparison between the relativistic and the classical results are also done for the different plasma conditions.

OICC PRESS A theoretical mesh-free scheme to model viscous drop interactions: a particle-based method Volume 7 (2013) Issue 1 2022 12 25 A theoretical mesh-free scheme to model viscous drop interactions: a particle-based method 10.1186/2251-7235-7-35 EN Journal Article 2022 12 25 AbstractHere a Lagrangian mesh-free formalism is presented to simulate the coalescence process between three unequal-sized liquid drops in the three-dimensional space. The surface tension forces acting on the surface of the drops cause the formation of a circular flat section when the droplets collide. The effect of polydispersity on the collision dynamics is simulated using a set of droplets with radius around 30 μm. It is important to see that the inhomogeneous distribution of the droplets size results in very important changes on the drops dynamics. The smoothed particle hydrodynamics scheme proposed here can be used to model situations where a continuum phase is included in the problem. The velocity vector fields are computed for each situation, and it can be seen that in the zone of contact between the droplets, there is an increment of the velocity value. This is due to the pressure distribution inside the drops.

OICC PRESS Determination of the amplitude-frequency for strongly nonlinear oscillator by two approximate analytical techniques Volume 7 (2013) Issue 1 2022 12 25 Determination of the amplitude-frequency for strongly nonlinear oscillator by two approximate analytical techniques 10.1186/2251-7235-7-38 EN Journal Article 2022 12 25 AbstractIn this paper, we investigate two of the analytical approximate techniques, energy balance method and amplitude-frequency formulation, and these approximate techniques are applied to solve the strongly nonlinear differential equation of a mass attached to the center of a stretched elastic wire. We present a comparative study between the energy balance method and amplitude-frequency formulation with exact solution. The approximate results reveal that these methods are very effective and convenient for determining the frequencies of nonlinear dynamical systems.

OICC PRESS Molecular structure, vibrational spectra, UV–vis, NBO, and NMR analyses on nevirapine using ab initio DFT methods Volume 7 (2013) Issue 1 2022 12 25 Molecular structure, vibrational spectra, UV–vis, NBO, and NMR analyses on nevirapine using ab initio DFT methods 10.1186/2251-7235-7-51 EN Journal Article 2022 12 25 AbstractNevirapine is an anti-human immunodeficiency virus (HIV) agent that belongs to the class of the non-nucleoside inhibitors of the HIV-1 virus reverse transcriptase. Spectral characteristics of nevirapine have been probed into by methods of Fourier transform infrared (FTIR), FT-Raman, UV-visible, and quantum chemistry. The UV spectrum was measured in methanol. In order to gain some valuable insight into the recorded spectrum, the quantum mechanical calculations were performed for nevirapine using both ZINDO and time-dependent density functional theory at B3LYP/6-31G(d,p) level. The optimized molecular geometry, bond orders, natural bond order analysis, and harmonic vibrational wavenumbers of nevirapine were calculated by restricted Hartree-Fock and density functional B3LYP methods with the 6-31G(d,p) basis set using Gaussian 03 W program. The harmonic vibrational frequencies calculated have been compared with experimental FTIR and FT-Raman spectra. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance (NMR) calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of nevirapine.

OICC PRESS String cloud and domain walls with quark matter in kink cosmological model Volume 7 (2013) Issue 1 2022 12 25 String cloud and domain walls with quark matter in kink cosmological model 10.1186/2251-7235-7-62 EN Journal Article 2022 12 25 AbstractWe have studied quark matter coupled with string cloud and domain walls in the context of general relativity. For this purpose, we solved Einstein’s field equations for quark matter coupled to the string cloud and domain walls in spherical symmetric kink space-time. It is found that cosmic strings and domain walls do not survive in this space-time. Hence, the space-time in both the cases reduces to Minkowskian and the space-time is flat.

OICC PRESS GEMs and amplitude bounds in the colored Boulatov model Volume 7 (2013) Issue 1 2022 12 25 GEMs and amplitude bounds in the colored Boulatov model 10.1186/2251-7235-7-63 EN Journal Article 2022 12 25 AbstractIn this paper, we construct a methodology for separating divergencies due to different topological manifolds dual to Feynman graphs in a colored group field theory. After having introduced the amplitude bounds using propagator cuts, we show how Graph-Encoded Manifold (GEM) techniques can be used in order to factorize divergencies related to different parts of the dual topologies of the Feynman graphs in the general case. We show the potential of the formalism in the case of three-dimensional solid torii in the colored Boulatov model.

OICC PRESS Nonstandard Lagrangian cosmology Volume 7 (2013) Issue 1 2022 12 25 Nonstandard Lagrangian cosmology 10.1186/2251-7235-7-58 EN Journal Article 2022 12 25 AbstractWe show that many independent scenarios as the ‘accelerated expansion of the universe’, ‘eternal inflation’, ‘eternally oscillating universe’, ‘nonsingular oscillating universe’, and ‘collapse of an oscillating universe’ may occur without modifying the gravity theory or introducing scalar fields of any type. This is achieved by replacing the standard Lagrangian in the Friedmann-Robertson-Walker spacetime model by an exponentially nonstandard Lagrangian which modify the Euler-Lagrange equation although the standard variational approach is used.PACS45.20.Jj; 98.80.-k

OICC PRESS Variational calculation with general density functional to solve the electronic Schrödinger equation directly for ground state: a recipe for self-consistent field solution Volume 7 (2013) Issue 1 2022 12 25 Variational calculation with general density functional to solve the electronic Schrödinger equation directly for ground state: a recipe for self-consistent field solution 10.1186/2251-7235-7-61 EN Journal Article 2022 12 25 AbstractUsing orbital-free framework, a simple numerical optimization of the density functional for ground state electronic energy is described for any type of functional approximation, demonstrated via the example of linear combinations of homogeneous functionals of the density. The numerical recipe is given and analyzed for solution: Originating from the linear dependence of nuclear-electron attraction functional on one-electron density (Vne[ρ0(r1)] = -ΣA = 1,…,MZA∫ρ0(r1)rA1-1dr1), and a quadratic LCAO approximation for ρ0, the optimization can be done with iterative use of lin-solver. This quadratic approximation, as simplest educated choice for ρ0, is compared and analyzed algebraically to the HF-SCF one in the Appendices. We call the attention that the introduction of a self-consistent field optimization of non-linear density functional is a new element in this part of the related, general theory.

OICC PRESS The effect of film thickness on surface morphology of ITO thin films Volume 7 (2013) Issue 1 2022 12 25 The effect of film thickness on surface morphology of ITO thin films 10.1186/2251-7235-7-21 EN Journal Article 2022 12 25 AbstractIn this work, we developed the rescaled range method and its formalism to investigate the surface morphology dynamics of indium tin oxide (ITO) thin films. The dynamic scaling behavior of grown ITO thin films, which were prepared by electron beam deposition method on float glass substrates at room temperature, was studied through atomic force microscopy (AFM). AFM data indicated that the average surface roughness values of the films decreased as the film thickness increased from 100 to 250 nm. Based on fractal concept and statistical physics techniques, the irregularities of the ITO films were analyzed. The roughness exponent H and the growth exponent β for ITO films were determined to be 0.71 ± 0.01 and 0.11 ± 0.01, respectively. The fractal analysis reveals that the value of the fractal dimension Df (Df = 3 − H) falls within the range 2.29 to 2.24 depending upon the films thickness. These results show that the growth process of the films can be described by the combination of Edwards-Wilkinson and Mullins diffusion models.

OICC PRESS Grand canonical ensemble of the extended two-site Hubbard model via a nonextensive distribution Volume 7 (2013) Issue 1 2022 12 25 Grand canonical ensemble of the extended two-site Hubbard model via a nonextensive distribution 10.1186/2251-7235-7-20 EN Journal Article 2022 12 25 AbstractWe hereby introduce a research about a grand canonical ensemble for the extended two-site Hubbard model, that is, we consider the intersite interaction term in addition to those of the simple Hubbard model. To calculate the thermodynamical parameters, we utilize the nonextensive statistical mechanics; specifically, we perform the simulations of magnetic internal energy, specific heat, susceptibility, and thermal mean value of the particle number operator. We found out that the addition of the intersite interaction term provokes a shifting in all the simulated curves. Furthermore, for some values of the on-site Coulombian potential, we realize that, near absolute zero, the consideration of a chemical potential varying with temperature causes a nonzero entropy.PACS75.10.Jm, 05.30.-d, 65.80.+n

OICC PRESS Investigation on the production of copper nitride (copper azide) thin films and their nanostructures Volume 7 (2013) Issue 1 2022 12 25 Investigation on the production of copper nitride (copper azide) thin films and their nanostructures 10.1186/2251-7235-7-2 EN Journal Article 2022 12 25 AbstractCopper thin films of 80-nm thickness were deposited on glass substrate using electron beam deposition at two different deposition angles of 0° and 40°, and they were post-annealed under flow of nitrogen at different temperatures. The structure of the films was analyzed using X-ray diffraction, atomic force microscope, and scanning electron microscope. Investigation on the copper nitride phase formation showed that this phase was not formed in the samples produced at 0°, while those prepared at oblique angle of 40° clearly showed the formation of copper azide phase. This is related to the porosity of the film structure, hence increased surface area for the reaction of nitrogen with copper atoms. Therefore, this is a simple method for preparation of copper nitride films that are not usually formed due to low reactivity of copper (as transition metal) with nitrogen. The results showed that the crystallite size (coherently diffracting domains), grain size, and surface roughness increase with annealing temperature.

OICC PRESS Design, synthesis, and characterization of TPA-thiophene-based amide or imine functionalized molecule for potential optoelectronic devices Volume 7 (2013) Issue 1 2022 12 25 Design, synthesis, and characterization of TPA-thiophene-based amide or imine functionalized molecule for potential optoelectronic devices 10.1186/2251-7235-7-4 EN Journal Article 2022 12 25 AbstractNew sets of molecules containing tri-phenyl-amine (TPA) core and thiophene unit with amide and imine functional groups are designed, synthesized, characterized, and compared. These are solution processable small molecules with high mobility. The newly designed molecules have better solubility due to the C=N (imine) and CONH2 (amide) moiety as compared to the established molecules with CH=CH (methine) for optoelectronic applications. They have an optimal energy band gap, which indicates their potential utility in a variety of optoelectronic applications. These molecules also show efficient intermolecular charge transfer mechanisms similar to conventional organic semiconducting molecules as evidenced by optical measurements. Density functional theory simulation results show that the localization of the frontier highest occupied molecular orbital is around the TPA core for molecules coupled with imine and amide, and is reasonably stable.

OICC PRESS Influence of the hot filament on the electrical breakdown characteristics in the presence of Ar/N2 Volume 7 (2013) Issue 1 2022 12 25 Influence of the hot filament on the electrical breakdown characteristics in the presence of Ar/N2 10.1186/2251-7235-7-5 EN Journal Article 2022 12 25 AbstractThe influence of a hot filament on the electrical breakdown characteristics is studied for different ratios of argon and nitrogen gases for a wide range of pressure. The vacuum tube consists of two parallel plane stainless steels used as cathode and anode accompanied with a tungsten filament located behind the cathode. Paschen’s curves are obtained for different ratios of argon and nitrogen as a function of pressure for various electric currents of the hot filament. The first and second Townsend coefficients as well as the ionization efficiency and secondary ionization coefficient are obtained for different filament currents. In addition, the influences of the nitrogen partial pressure on the forgoing parameters are obtained. It is shown that, increase of the filament current causes the decrease of the electrical breakdown voltage which is more pronounced in low pressures. Furthermore, introducing the nitrogen gas leads to the increase of the breakdown voltage and decrease of the ionization efficiency as well as the first and second Townsend coefficients. Moreover, it is concluded that, in the middle range of pressure, the presence of the hot filament results to the electrical breakdown which reveals the linear features.

OICC PRESS Semiempirical investigations on the stabilization energies and ionic hydrogen-bonded structures of F−(H2O)n and Cl−(H2O)n (n = 1–4) clusters Volume 7 (2013) Issue 1 2022 12 25 Semiempirical investigations on the stabilization energies and ionic hydrogen-bonded structures of F−(H2O)n and Cl−(H2O)n (n = 1–4) clusters 10.1186/2251-7235-7-7 EN Journal Article 2022 12 25 AbstractSeveral semiempirical methods were utilized to analyze the structures and stabilities of X−(H2O)n (X = F, Cl; n = 1–4) clusters with respect to the number of water molecules through their comparison with ab initio molecular orbital calculations. Our results show that the recently developed PM6-DH+ semiempirical method can provide reasonable binding energies of hydrated fluoride and chloride ion clusters, which are consistent with the corresponding experimental results. For the optimized geometries of X = F, however, the semiempirical methods show that the global minima are close to HF(OH)−(H2O)n−1 structures, which are different from the ab initio calculations. Meanwhile, the topological characteristics for the global minima of X = Cl obtained by semiempirical methods have the same symmetries with ab initio calculations. All calculation levels agree on the trend of decreasing ion-water interaction with the increasing number of water molecules. We also found a new structure of Cl−(H2O)4 with a second hydration shell as a complement of previous studies. Those are very important data for our near-future study of on-the-fly semiempirical molecular dynamics (MD) or path integral MD simulation.PACS36.40.Mr, 31.15.bu, 31.15.A-

OICC PRESS The effect of MgO doping on the structural, magnetic, and magnetotransport properties of La0.8Sr0.2MnO3 manganite Volume 7 (2013) Issue 1 2022 12 25 The effect of MgO doping on the structural, magnetic, and magnetotransport properties of La0.8Sr0.2MnO3 manganite 10.1186/2251-7235-7-1 EN Journal Article 2022 12 25 AbstractThe effect of MgO doping on the structural, magnetic, and magnetotransport properties of La0.8Sr0.2MnO3 (LSMO)/x MgO has been investigated. All samples were prepared by a solid-state reaction method. Alternating current susceptibility measurements for LSMO/x MgO samples show that the Curie transition temperature (Tc) and magnetization decrease with the increase of MgO concentration. The rate of the decrease of Tc at higher doping level is very fast. Also, samples with low doping level (x ≤ 2) show insulator-metal transition, but the transition temperature decreases and resistivity increases with the amount of MgO. It is observed that there is no insulator-metal transition at higher MgO doping level (x ≥ 3). Also, the results show that the value of low-field magnetoresistance decreases with the increase of MgO doping level. It seems that due to the higher sintering temperature and almost the same ionic radii of Mg2+ and Mn3+, Mg2+ mostly replaced Mn3+ and weakened the double-exchange interaction, and consequently, Tc and magnetoresistance decrease and resistivity increases with MgO doping.

OICC PRESS Electronic and magnetic properties of a full-Heusler alloy Co2CrGe: a first-principles study Volume 7 (2013) Issue 1 2022 12 25 Electronic and magnetic properties of a full-Heusler alloy Co2CrGe: a first-principles study 10.1186/2251-7235-7-3 EN Journal Article 2022 12 25 AbstractThe structural, electronic, and magnetic properties of Co2CrGe, a Heusler alloy, have been evaluated by first-principles density functional theory and compared with the known experimental and theoretical results. Generalized gradient approximation is used for structural study, whereas local spin density approximation is used for electronic calculation. First-principles structure optimizations were done through total energy calculations at 0 K using the full-potential linearized augmented plane wave method as implemented in the WIEN2K code.

OICC PRESS Finite element formulation for the free vibration analysis of embedded double-walled carbon nanotubes based on nonlocal Timoshenko beam theory Volume 7 (2013) Issue 1 2022 12 25 Finite element formulation for the free vibration analysis of embedded double-walled carbon nanotubes based on nonlocal Timoshenko beam theory 10.1186/2251-7235-7-6 EN Journal Article 2022 12 25 AbstractThe present paper is concerned with the free vibration analysis of double-walled carbon nanotubes embedded in an elastic medium and based on Eringen's nonlocal elasticity theory. The effects of the transverse shear deformation and rotary inertia are included according to the Timoshenko beam theory. The governing equations of motion which are coupled with each other via the van der Waals interlayer forces have been derived using Hamilton's principle. The thermal effect is also incorporated into the formulation. Using the statically exact beam element with displacement fields based on the first order shear deformation theory, the finite element method is employed to discretize the coupled governing equations which are then solved to find the natural frequencies. The effects of the small scale parameter, boundary conditions, thermal effect, changes in material constant of the surrounding elastic medium, and geometric parameters on the vibration characteristics are investigated. Furthermore, our analysis includes nonlocal double-walled carbon nanotubes with different boundary conditions between inner and outer tubes which seem to be scarcely considered in the literature, and the corresponding given results for this case can be considered as a benchmark for further studies. Comparison of the present numerical results with those from the open literature shows an excellent agreement.

OICC PRESS The comparison of homotopy perturbation method with finite difference method for determination of maximum beam deflection Volume 7 (2013) Issue 1 2022 12 25 The comparison of homotopy perturbation method with finite difference method for determination of maximum beam deflection 10.1186/2251-7235-7-8 EN Journal Article 2022 12 25 AbstractThis paper deals with the determination of maximum beam deflection using homotopy perturbation method (HPM) and finite difference method (FDM). By providing some examples, we compare the results with exact solutions and conclude that HPM is more accurate, more stable and effective and can therefore be found widely applicable in structrue engineering.

OICC PRESS Calculation of state energy of (2n+ 1)-fold wells using the spectral properties of supersymmetry shape-invariant potential Volume 7 (2013) Issue 1 2022 12 25 Calculation of state energy of (2n+ 1)-fold wells using the spectral properties of supersymmetry shape-invariant potential 10.1186/2251-7235-7-10 EN Journal Article 2022 12 25 AbstractShape invariance is an important factor of many exactly solvable quantum mechanics. Several examples of shape-invariant ‘discrete quantum mechanical systems’ are introduced and discussed in some detail. We present the spectral properties of supersymmetric shape-invariant potentials (SIP). Here we are interested in some time-independent integrable systems which are exactly solvable owing to the existence of supersymmetric shape-invariant symmetry. In 1981 Witten proposed (0+1)-dimensional limit of supersymmetry (SUSY) quantum field theory, where the supercharges of SUSY quantum mechanics generate transformation between two orthogonal eigenstates of a given Hamiltonian wit degenerate eigenvaluesfor the non-SIP as very few lower eigenvalues can be known analytically, which are small to calculate spectral fluctuation.

OICC PRESS A method to improve the accuracy of diode in vivo dosimetry for external megavoltage photon beams filtered by wedges Volume 7 (2013) Issue 1 2022 12 25 A method to improve the accuracy of diode in vivo dosimetry for external megavoltage photon beams filtered by wedges 10.1186/2251-7235-7-13 EN Journal Article 2022 12 25 AbstractDiode in vivo dosimetry is widely considered to be an important tool for quality improvement of patient care in external radiotherapy. In vivo dose measurements for wedged photon beams require correction factor estimation for difference in wedge angles and field sizes. The diode dosimeters that were used in this study were two different models of PTW products; T60010L and T60010M models were used for 60Co and 6-MV photon beams, respectively. The values of off-axis wedge correction factor were determined at two different physical situations in the wedged and non-wedged directions on the entrance surface of the polystyrene phantom. The wedge correction factor at various depths was then estimated by a proposed method. Results show that the absorbed dose at each depth can be estimated by applying accurate wedge correction factor at depth, on entrance surface dose with negligible probable errors (below 1.2%).

OICC PRESS Anomaly in the specific heat of lead tellurides Volume 7 (2013) Issue 1 2022 12 25 Anomaly in the specific heat of lead tellurides 10.1186/2251-7235-7-11 EN Journal Article 2022 12 25 AbstractSpecific heats of two types of lead tellurides, namely p-type Pb1-xSnxTe (x = 0.0, 0.1, 0.3, 0.5, 0.7, 0.9, 1.0) and n-type PbTe doped with y mass% PbI2 (y = 0.0, 0.2, 0.5, 0.8, 1.0), were observed in the temperature range of 50°C to 500°C using a differential scanning calorimeter (DSC). The specific heat of pure Te is also observed in the same temperature range to confirm the dominance of Te. At lower temperatures below 200°C, all the observed data were fairly consistent with those predicted on the basis of Dulong-Petit’s law, while above 200°C, the observed data showed curious temperature dependences. At high temperatures above 200°C, DSC analysis, with the aid of the experiment on pure Te, revealed an anomalously large specific heat that can be predicted from the Schottky defects caused by decomposition and sublimation of Te. In the n-type case, the anomaly in specific heats is rather smaller than that in the p-type case, which fact suggested that the dopant PbI2 may suppress the decomposition and sublimation of Te from lead tellurides.

OICC PRESS Evolutionary behavior of weak shocks in a non-ideal gas Volume 7 (2013) Issue 1 2022 12 25 Evolutionary behavior of weak shocks in a non-ideal gas 10.1186/2251-7235-7-14 EN Journal Article 2022 12 25 AbstractExcept some empirical methods, which have been developed in the past, no analytical method exists to describe the evolutionary behavior of a shock wave without limiting its strength. In this paper, we have derived a system of transport equations for the shock strength and the induced continuity. We generate a completely intrinsic description of plane, cylindrical, and spherical shock waves of weak strength, propagating into a non-ideal gas. It is shown that for a weak shock, the disturbance evolves like an acceleration wave at the leading order. For a weak shock, we may assume that p=Oϵ,0

OICC PRESS Recombination phenomenon in polyethylene under space charge dynamics and its effects on the external current evolution Volume 7 (2013) Issue 1 2022 12 25 Recombination phenomenon in polyethylene under space charge dynamics and its effects on the external current evolution 10.1186/2251-7235-7-18 EN Journal Article 2022 12 25 AbstractThis paper presents bipolar transport model results concerning the recombination phenomenon in a low-density polyethylene under direct current (dc) applied voltages. Results obtained indicate the existence of a threshold value of voltage between two different space charge dynamics. Indeed, we show that under low dc applied voltage, the total recombination rate density is dominated by the recombination between trapped electrons and trapped holes, while under high dc voltage, the recombination is governed by mobile electron-trapped hole and trapped electron-mobile hole recombinations. This is due to the fact that under low dc voltage, trapped charges dominate, while under high voltage, mobile charge density is much higher. In addition, we show the significant effect of the recombination phenomenon on the external current evolution at transient and steady states.

OICC PRESS Mechanical properties of CaN, SrN, and BaN compounds by density functional theory Volume 7 (2013) Issue 1 2022 12 25 Mechanical properties of CaN, SrN, and BaN compounds by density functional theory 10.1186/2251-7235-7-16 EN Journal Article 2022 12 25 AbstractUsing density functional theory, a systematic study of the elastic properties of CaN, SrN, and BaN compounds is performed. As a result, the optimized lattice parameters and independent elastic constants are calculated within the generalized gradient approximation. We have also derived bulk and shear moduli, Young’s moduli, Poisson’s ratio, and brittle/ductile behavior for CaN, SrN, and BaN. The estimated anisotropy parameter, A, shows that SrN has higher degree of elastic isotropy in comparison to CaN and BaN.

OICC PRESS Modified Brillouin function to explain the ferromagnetic behavior of surfactant-aided synthesized α-Fe2O3 nanostructures Volume 7 (2013) Issue 1 2022 12 25 Modified Brillouin function to explain the ferromagnetic behavior of surfactant-aided synthesized α-Fe2O3 nanostructures 10.1186/2251-7235-7-19 EN Journal Article 2022 12 25 AbstractThe α-Fe2O3 nanoparticles have been synthesized using some surfactants in micro-emulsion method. Magnetization, M (H), of samples was measured at room temperature. Magnetic hysteresis loops were observed in all samples. A new magnetization function (H - A model) was offered to explain the field dependence of the magnetization behavior of α-Fe2O3. In this work, the magnetization curve of all samples was analyzed based on MBrillouin, MBrillouin-Akulov, and MBrillouin-(H - A) model. The experimental data have fitted with the MBrillouin-(H - A) model, and the best fitting parameters were analyzed.

OICC PRESS Ultrasonic studies of ternary liquid mixtures of N-N-dimethylformamide, nitrobenzene, and cyclohexane at different frequencies at 318 K Volume 7 (2013) Issue 1 2022 12 25 Ultrasonic studies of ternary liquid mixtures of N-N-dimethylformamide, nitrobenzene, and cyclohexane at different frequencies at 318 K 10.1186/2251-7235-7-23 EN Journal Article 2022 12 25 AbstractThe ultrasonic velocity, density, and viscosity have been measured for ternary mixtures of nitrobenzene, N,N-dimethylformamide, and cyclohexane at temperature T = 318 K at different frequencies such as 2, 4, 6, and 8 MHz. The experimental data have been used to calculate the acoustical and thermodynamical parameters like adiabatic compressibility, free length, free volume, internal pressure, acoustic impedance, Gibbs free energy, and their excess values. In particular, it is seen that the response of these parameters to frequency is less prominent in comparison to that of the ternary mixtures containing N,N-dimethylformamide, cyclohexane, and chlorobenzene.

OICC PRESS Grand canonical ensemble of the extended two-site Hubbard model via a nonextensive distribution Volume 7 (2013) Issue 1 2022 12 25 Grand canonical ensemble of the extended two-site Hubbard model via a nonextensive distribution 10.1186/2251-7235-7-20 EN Journal Article 2022 12 25 AbstractWe hereby introduce a research about a grand canonical ensemble for the extended two-site Hubbard model, that is, we consider the intersite interaction term in addition to those of the simple Hubbard model. To calculate the thermodynamical parameters, we utilize the nonextensive statistical mechanics; specifically, we perform the simulations of magnetic internal energy, specific heat, susceptibility, and thermal mean value of the particle number operator. We found out that the addition of the intersite interaction term provokes a shifting in all the simulated curves. Furthermore, for some values of the on-site Coulombian potential, we realize that, near absolute zero, the consideration of a chemical potential varying with temperature causes a nonzero entropy.PACS75.10.Jm, 05.30.-d, 65.80.+n

OICC PRESS Auto-Bäcklund transformation and new exact solutions of the (3+1)-dimensional KP equation with variable coefficients Volume 7 (2013) Issue 1 2022 12 24 Auto-Bäcklund transformation and new exact solutions of the (3+1)-dimensional KP equation with variable coefficients 10.1186/2251-7235-7-49 EN Jian-Guo Liu College of Computer, Jiangxi University of Traditional Chinese Medicine Zhifang Zeng College of Science, Nanchang University Journal Article 2022 12 24 AbstractThe (3+1)-dimensional variable coefficient Kadomtsev-Petviashvilli equation describes the dynamics of solitons and nonlinear waves in plasmas and superfluids. Based on computerized symbolic computation and extended variable coefficient homogeneous balance method, several families of exact soliton-like solutions, rational solutions, and auto-Bäcklund transformation are presented. With the use of the auto-BT and the ε-expansion method, we can obtain a soliton-like solution including N-solitary wave of the (3+1)-dimensional Kadomtsev-Petviashvilli equation with variable coefficients. Especially, we get a soliton-like solution including two-solitary waves as an illustrative example in detail.

OICC PRESS A DFT study of interaction of hydrogen molecules and (5,5) carbon nanotube with bioinspired functionalization Volume 7 (2013) Issue 1 2022 12 24 A DFT study of interaction of hydrogen molecules and (5,5) carbon nanotube with bioinspired functionalization 10.1186/2251-7235-7-56 EN Md Shahzad Khan Department of Physics, Jamia Millia Islamia Mohd Shahid Khan Department of Physics, Jamia Millia Islamia Journal Article 2022 12 24 AbstractAll electron density functional theory (DFT) calculations have been carried out for calcium-doped porphyrin-incorporated(5, 5) carbon nanotube (Ca-PICNT) to investigate the formation energies, electronic properties of this system, and its application in hydrogen storage. It is found that the incorporation of porphyrin ring in carbon nanotube led to a decreased value of the highest occupied molecular orbital and lowest unoccupied molecular orbital gap and a strong binding of Ca over nanotube and consequently resulted to a drastic reduction of clustering of Ca atom over Ca-decorated carbon nanotube. The Ca-PICNT can bind a maximum of 4H2 with binding energy value of 0.105 eV per H2 molecule. Charge decomposition analysis indicated that the mode of hydrogen storage is via coulomb-electrostatic force, which is further supported by the natural bond orbital and partial density-of-states studies.

OICC PRESS Effect of obliqueness of external magnetic field on the characteristics of magnetized plasma wakefield Volume 7 (2013) Issue 1 2022 12 24 Effect of obliqueness of external magnetic field on the characteristics of magnetized plasma wakefield 10.1186/2251-7235-7-43 EN Maryam Manouchehrizadeh Physics Department, Science Faculty, Islamic Azad University Tehran Central Branch Davoud Dorranian Plasma Physics Research Centre, Science and Research Branch, Islamic Azad University, Tehran, Iran 0000-0001-8855-7425 Journal Article 2022 12 24 AbstractA direct three-dimensional model to study the wakefield in underdense magnetized plasma is introduced. The model is based on an analytic procedure by Laplace transformation for calculating the magnetized plasma wake equations. Wakefield is excited using a high-intensity ultrashort laser beam. In the presence of external magnetic field perpendicular to the direction of the laser pulse propagation direction, plasma electrons rotate around the magnetic field lines, leading to the generation of an electromagnetic component of the plasma wakes at plasma frequency. This component is polarized perpendicularly to the direct current magnetic field lines and propagates in the forward direction and normal direction with respect to the laser pulse propagation direction, both perpendiculars to the direction of the applied magnetic field. Intensity of the radiation in different plasma densities and different magnetic field strengths has been observed.  

OICC PRESS Lie algebra method for solving biological population model Volume 7 (2013) Issue 1 2022 12 24 Lie algebra method for solving biological population model 10.1186/2251-7235-7-67 EN Journal Article 2022 12 24 AbstractIn this paper, the Lie algebraic method is applied to solve biological population models described by time-inhomogeneous birth-death processes. Notwithstanding no obvious symmetry, the solution is expressed by matrix exponentials through suitably generated low-dimensional Lie algebras. This methodology may offer useful insights for other biological and ecological applications.  

OICC PRESS Ground-state energy band of even 104-122Cd isotopes under the framework of interacting boson model-1: a review Volume 7 (2013) Issue 1 2022 12 24 Ground-state energy band of even 104-122Cd isotopes under the framework of interacting boson model-1: a review 10.1186/2251-7235-7-46 EN Journal Article 2022 12 24 AbstractIn this paper, the nuclear structure of ground-state bands of even-even 104-122Cd isotopes has been reviewed under the framework of interacting boson model-1 (IBM-1). The theoretical energy levels for Z = 48, even N = 56–74 up to 8+ state have been obtained by using the PHINT computer program. The values of the parameters in the IBM-1 Hamiltonian yield the best fit to the experimental energy spectrum. The results are compared with the most recent experimental values where an acceptable degree of agreement is achieved. In this paper, the properties of even 104-122Cd isotopes have been considered to the U(5) ~ SO(6) transitional region of the IBM-1.  

OICC PRESS Calculation of full-energy peak efficiency of NaI (Tl) detectors by new analytical approach for parallelepiped sources Volume 7 (2013) Issue 1 2022 12 24 Calculation of full-energy peak efficiency of NaI (Tl) detectors by new analytical approach for parallelepiped sources 10.1186/2251-7235-7-52 EN Journal Article 2022 12 24 AbstractA new analytical approach is presented for the calculation of full-energy peak (FEP) efficiency of NaI (Tl) detectors. The self-attenuation of the parallelepiped source matrix, the attenuation by the source container, and the detector housing materials were considered in the mathematical treatment. The efficiency values calculated using the presently suggested analytical approach are compared with those measured values obtained by two different sizes of NaI (Tl) detectors. The calculated and the measured full-energy peak efficiency values were in a good agreement.    

OICC PRESS Abnormal electronic transport in disordered four-terminal graphene nanodevice Volume 7 (2013) Issue 1 2022 12 24 Abnormal electronic transport in disordered four-terminal graphene nanodevice 10.1186/2251-7235-7-54 EN Journal Article 2022 12 24 AbstractIn this paper, a numerical study of quantum transport in a disordered four-terminal graphene nanodevice is investigated based on the Landauer approach. The effects of impurity on transmission coefficient of the electron injected into the system are studied using tight-binding model. In this manner, we emphasize that when the disorder density is sufficiently large, the transmission coefficients and the current reduce due to multiscattering phenomenon. We have found that the perfectly conducting channel develops in four-terminal device in its zigzag edge if the range of impurity gets exponentially wider. The theoretical results obtained can be a base for the development in designing graphene nanodevice.    

OICC PRESS Some consequences of nonstandard Lagrangians with time-dependent coefficients in general relativity Volume 7 (2013) Issue 1 2022 12 24 Some consequences of nonstandard Lagrangians with time-dependent coefficients in general relativity 10.1186/2251-7235-7-60 EN Journal Article 2022 12 24 AbstractNonstandard Lagrangians entitled ‘nonnaturals’ by Arnold have recently gained increasing importance both in applied mathematics and in physical theories. These types of Lagrangians appear in some group of dissipative dynamical systems, and they play an important role in a number of field theories. However, the role of nonstandard Lagrangians in geometric theories like general relativity is still absent. In this communication, we would like to discuss the relevance of nonstandard Lagrangians in general relativity using the principles of calculus of variations. In fact, nonstandard Lagrangians came in different forms, features, and characteristics, depending on the nature of the dynamical problem under study. In this work, we will be concerned with time-dependent Lagrangians of the form L1 + γ(t). After deriving the modified geodesic equation using the basic techniques of Riemannian differential geometry which will be used to axiomatize a large part of our work, we show that many interesting consequences will be raised accordingly when applied to FRW cosmology.  

OICC PRESS A new Coulomb ring-shaped potential via generalized parametric Nikiforov-Uvarov method Volume 7 (2013) Issue 1 2022 12 24 A new Coulomb ring-shaped potential via generalized parametric Nikiforov-Uvarov method 10.1186/2251-7235-7-17 EN Journal Article 2022 12 24 AbstractIn this paper, the Schrödinger equation is analytically solved for the Coulomb potential with a novel angle-dependent part. The generalized parametric Nikiforov-Uvarov method is used to obtain energy eigenvalues and corresponding eigenfunctions. We presented the effect of the angle-dependent part on radial solutions and some special cases are also discussed.  

OICC PRESS Reconstruction of modified holographic Ricci dark energy in El-Nabulsi fractional action cosmology Volume 7 (2013) Issue 1 2022 12 24 Reconstruction of modified holographic Ricci dark energy in El-Nabulsi fractional action cosmology 10.1186/2251-7235-7-22 EN Journal Article 2022 12 24 AbstractIn this work, we discussed the ‘modified holographic Ricci dark energy’ cosmological model based on El-Nabulsi fractional action cosmology. corresponding related cosmological parameters have been reconstructed. It has been observed that the equation of state parameter behaves like quintessence. Finally, through a test by the squared speed of sound, the proposed reconstruction model is found to be classically unstable.PACS 95.36.+x, 95.35.+d    

OICC PRESS Optimized basis expansion as an extremely accurate technique for solving time-independent Schrödinger equation Volume 7 (2013) Issue 1 2022 12 24 Optimized basis expansion as an extremely accurate technique for solving time-independent Schrödinger equation 10.1186/2251-7235-7-34 EN Journal Article 2022 12 24 AbstractWe use the optimized trigonometric finite basis method to find energy eigenvalues and eigenfunctions of the time-independent Schrödinger equation with high accuracy. We apply this method to the quartic anharmonic oscillator and the harmonic oscillator perturbed by a trigonometric anharmonic term as not exactly solvable cases and obtain the nearly exact solutions.    

OICC PRESS Study on kink space-time in scale invariant theory with wet dark fluid Volume 7 (2013) Issue 1 2022 12 24 Study on kink space-time in scale invariant theory with wet dark fluid 10.1186/2251-7235-7-36 EN Journal Article 2022 12 24 AbstractIn this paper, the kink space-time with wet dark fluid in scale invariant theory of gravitation is investigated. The gauge function β is considered as β = β(r) and β = β(t). The matter field is assumed to be perfect fluid. It has been found that perfect fluid does not survive in this theory in both the cases. Hence, the space-time in both the cases reduces to Minkowskian geometry and the space-time is flat.AMS83F05  

OICC PRESS Influence of argon gas flow on mechanical and electrical properties of sputtered titanium nitride thin films Volume 7 (2013) Issue 1 2022 12 24 Influence of argon gas flow on mechanical and electrical properties of sputtered titanium nitride thin films 10.1186/2251-7235-7-37 EN Journal Article 2022 12 24 AbstractTitanium nitrides have good mechanical, tribological, electrical, biomedical, and optical properties; therefore, they are used to harden and protect cutting and sliding surfaces, as semiconductor devices, and as a nontoxic exterior for biomedical applications. The dependence of the mechanical and electrical properties of titanium nitride thin films deposited on silicon substrates by direct-current reactive magnetron sputtering technique on argon gas flow (in the range of 8 to 20 sccm) was investigated. The crystallographic structure of the films was studied by X-ray diffraction (XRD), while surface morphology was studied using atomic force microscopy (AFM). Mechanical and electrical properties of these films were investigated by nanoindentation test and a four-point probe instrument, respectively. The XRD patterns showed titanium nitride (TiN) formation with a face-centered cubic structure for all samples. It was also observed that (111) crystallographic direction was the preferred orientation for TiN thin films which became more pronounced with increasing argon gas flow. The AFM images showed a granular structure for TiN layers. The hardness, crystallite/grain size (obtained from XRD and AFM), and surface roughness increased with the flow of argon gas, while elastic modulus and dislocation density in the films decreased. The study on electrical properties showed that the dependence of voltage with current for all samples was linear, and film resistivity was increased with argon gas flow.    

OICC PRESS Analysis of positron profiling data by ROYPROF, VEPFIT, and POSTRAP4 codes: a comparative study Volume 7 (2013) Issue 1 2022 12 24 Analysis of positron profiling data by ROYPROF, VEPFIT, and POSTRAP4 codes: a comparative study 10.1186/2251-7235-7-39 EN Journal Article 2022 12 24 AbstractThe programs ROYPROF, VEPFIT, and POSTRAP4 are widely used in the field of positron physics. They are mainly employed in analyzing experimental Doppler-broadened data from studying condensed matter samples with variable energy positron beams. A comparative study of analysis results on the same set of data has shown to be consistent. Performance differences are reported. The small differences found may not lead to wrong interpretation of physical results.    

OICC PRESS Exact solutions of Feinberg-Horodecki equation for time-dependent Deng-Fan molecular potential Volume 7 (2013) Issue 1 2022 12 24 Exact solutions of Feinberg-Horodecki equation for time-dependent Deng-Fan molecular potential 10.1186/2251-7235-7-40 EN Journal Article 2022 12 24 AbstractThe exact bound state solutions of the Feinberg-Horodecki equation with the rotating time-dependent Deng-Fan oscillator potential are presented within the framework of the generalized parametric Nikiforov-Uvarov method. It is shown that the solutions can be expressed in terms of Jacobi polynomials or the generalized hypergeometric functions. The energy eigenvalues and the corresponding wave functions are obtained in closed forms.  

OICC PRESS Retraction Note: Torsion of space-time in f (R) gravity Volume 7 (2013) Issue 1 2022 12 24 Retraction Note: Torsion of space-time in f (R) gravity 10.1186/2251-7235-7-32 EN Journal Article 2022 12 24

OICC PRESS Modification of surface energy and electrical and thermal properties of spherical polypyrrole nanoparticles synthesized by CTAB for potential application as a conductive ink Volume 7 (2013) Issue 1 2022 12 24 Modification of surface energy and electrical and thermal properties of spherical polypyrrole nanoparticles synthesized by CTAB for potential application as a conductive ink 10.1186/2251-7235-7-42 EN Journal Article 2022 12 24 AbstractPolypyrrole (PPy) fine powder was synthesized via a chemical route in the presence of various concentrations of the cationic surfactant cetyltrimethylammonium bromide. The effect of the concentration of the surfactant used on electronic, structural, thermal, and surface properties of the final product was investigated. The sample prepared with the highest concentration of surfactant yielded mostly the best electronic, thermal, and physical characteristic properties, a lot closer to the materials used in conductive inks. The electrical conductivity of the sample underwent an increase of 320%. Fourier transform infrared spectroscopy indicated that all surfactant has been excluded at the final stage of the synthesis, and the results indicated higher doping levels for higher concentrations of surfactant used. Surface energy showed a dramatic increase, and spherical nanoparticles were seen in scanning electron microscopy images. The PPy powder became soluble in polar solvents, becoming highly hydrophilic and indicating good mass retention upon thermal degradation.  

OICC PRESS Size distribution control of FePt nanocrystals by superhydride Volume 7 (2013) Issue 1 2022 12 24 Size distribution control of FePt nanocrystals by superhydride 10.1186/2251-7235-7-44 EN Journal Article 2022 12 24 AbstractFePt nanoparticle systems with high magnetocrystaline anisotropy in L10 phase are proper candidates for application in magnetic information storage with density more than Gbit/in2. FePt nanoparticles are grown by Pt(acac)2 and FeCl2. 4H2O compounds in phenyl ether solvent using weak reducing agent 1,2Hexadecandiol (C16H34O2) and strong reducing agent superhydride (LiBEt3H) in two steps. Structural and magnetic properties of the nanocrystals are studied by XRD, EDS and VSM analysis. Also, the growth mechanism and the effect of double-stage growth on size distribution and the size of FePt nanoparticles are determined. For this purpose, TEM images and EDS results are used. The results show that such growth as “core-shell” leads to form 5-nm, nearly monosized FePt nanoparticles, in which a relative standard deviation is decreased from 18% to 8%.  

OICC PRESS Characteristics of charged pions in the quark model with potential which is the sum of the Coulomb and oscillator potential Volume 7 (2013) Issue 1 2022 12 24 Characteristics of charged pions in the quark model with potential which is the sum of the Coulomb and oscillator potential 10.1186/2251-7235-7-47 EN Journal Article 2022 12 24 AbstractIn this paper, we calculate the polarizability of the charged pions in the nonrelativistic quark potential model.  

OICC PRESS Two-parameter determinant representation of seventh order rogue wave solutions of the NLS equation Volume 7 (2013) Issue 1 2022 12 24 Two-parameter determinant representation of seventh order rogue wave solutions of the NLS equation 10.1186/2251-7235-7-45 EN Pierre Gaillard Universit ́e de Bourgogne Franche Comt ́e, Institut de math ́ematiques de Bourgogne, Dijon Cedex, France Journal Article 2022 12 24 AbstractWe present a new representation of solutions of focusing nonlinear Schrödinger equation (NLS) equation as a quotient of two determinants. We construct families of quasi-rational solutions of the NLS equation depending on two parameters, a and b. We construct, for the first time, analytical expressions of Peregrine breather of order 7 and multi-rogue waves by deformation of parameters. These expressions make possible to understand the behavior of the solutions. In the case of the Peregrine breather of order 7, it is shown for great values of parameters a or b the appearance of the Peregrine breather of order 5.PACS35Q55; 37K10      

OICC PRESS String cosmological models with bulk viscosity in Nordtvedt’s general scalar-tensor theory of gravitation Volume 7 (2013) Issue 1 2022 12 24 String cosmological models with bulk viscosity in Nordtvedt’s general scalar-tensor theory of gravitation 10.1186/2251-7235-7-50 EN Uma Maheswara Rao Velagapudi Department of Applied Mathematics, Andhra University Neelima Davuluri Department of Applied Mathematics, Andhra University Journal Article 2022 12 24 AbstractWe have obtained and presented spatially homogeneous Bianchi types II, VIII, and IX string cosmological models with bulk viscosity in Nordtvedt's (Astrophys. J. 161:1059, 1970) general scalar-tensor theory of gravitation with the help of a special case proposed by Schwinger. It is observed that only the bulk viscous cosmological model exists in the case of Bianchi type IX universe. Some important features of the models, thus obtained, have been discussed.      

OICC PRESS Behavior of interacting Ricci dark energy in logarithmic f(T) gravity Volume 7 (2013) Issue 1 2022 12 24 Behavior of interacting Ricci dark energy in logarithmic f(T) gravity 10.1186/2251-7235-7-48 EN Rahul Ghosh Department of Mathematics, Bhairab Ganguly College Antonio Pasqua Department of Physics, University of Trieste Surajit Chattopadhyay Department of Computer Application (Mathematics Section), Pailan College of Management and Technology, West Bengal University of Technology 0000-0003-0666-1347 Journal Article 2022 12 24 AbstractIn the present work, we have considered a modified gravity model dubbed as ‘logarithmic f(T) gravity’ as reported by Bamba et al. (J. Cosmol. Astropart. Phys 1101:21, 2011) and investigated the behavior of Ricci dark energy interacting with pressureless Dark Matter. We have chosen the interaction term in the form Q=3Hδρm and investigated the behavior of the Hubble parameter H as a function of the redshift z. For this reconstructed H, we have investigated the behavior of the fractional density contribution due to the Ricci dark energy and torsion. Subsequently, we investigated the equation of state parameter wRDE which is found to have a phantom-like behavior for all choices of c2 in the Ricci dark energy density.PACS98.80.-k;95.36.+x;04.50.Kd    

OICC PRESS Pretend model of traveling wave solution of two-dimensional K-dV equation Volume 7 (2013) Issue 1 2022 12 24 Pretend model of traveling wave solution of two-dimensional K-dV equation 10.1186/2251-7235-7-64 EN Journal Article 2022 12 24 AbstractTraveling wave resolution of Korteweg-de Vries (K-dV) solitary and numerical estimation of analytic solutions have been studied in this paper for imaginary concept. Pretend model of traveling wave deals with giant waves or series of waves created by an undersea earthquake, volcanic eruption or landslide. The concept of traveling wave is frequently used by mariners and in coastal, ocean and naval engineering. We have found some exact traveling wave solutions with relevant physical parameters using new auxiliary equation method introduced by Pang et al. (Appl. Math. Mech-Engl. Ed 31(7):929–936, 2010). We have solved the imaginary part of exact traveling wave equations analytically, and numerical results of time-dependent wave solutions have been presented graphically. This procedure has a potential to be used in more complex system for other types of K-dV equations.    

OICC PRESS Compressive solitons in a moving e-p plasma under the effect of dust grains and an external magnetic field Volume 7 (2013) Issue 1 2022 12 24 Compressive solitons in a moving e-p plasma under the effect of dust grains and an external magnetic field 10.1186/2251-7235-7-65 EN Journal Article 2022 12 24 AbstractA theoretical investigation concerning the propagation of compressive solitons in a plasma comprising electrons, positrons, and dust grains is presented by considering the dust grains of either positive charge or negative charge. Using reductive perturbation technique, a relevant Korteweg-deVries (KdV) equation is derived and then solved to obtain the expressions of amplitude and width of the solitons. The magnetic field is found to alter the dispersive property of the plasma, and hence, only the width of the solitons is reduced in the presence of higher magnetic field. Soliton amplitude is found to decrease/increase and the width to increase/decrease for the higher densities of negatively/positively charged dust grains. Moreover, the amplitude of such a soliton remains larger in the case of positively charged dust grains in comparison with the negatively charged dust grains. The effect of electron/positron drift velocities of the charged species is not pronounced on the properties of the compressive solitons. Under the limiting cases, our calculations reduce to the calculations by other investigators. This substantiates the generality of the present analysis.  

OICC PRESS Structural, electrical, and decorative properties of sputtered zirconium thin films during post-annealing process Volume 7 (2013) Issue 1 2022 12 24 Structural, electrical, and decorative properties of sputtered zirconium thin films during post-annealing process 10.1186/2251-7235-7-55 EN Kaykhosrow Khojier Department of Physics, Chalous Branch, Islamic Azad University Hadi Savaloni School of Physics, College of Science, University of Tehran, North‑Kargar Street, Tehran, Iran 0000-0002-6836-106X Fatemeh Jafari Department of Physics, Faculty of Science, Central Tehran Branch, Islamic Azad University Journal Article 2022 12 24 AbstractZirconium thin films were deposited on a glass substrate using direct current magnetron sputtering technique and then post-annealed at different temperatures (100°C to 500°C in steps of 100°C) in an oxygen constant flow. The dependence of crystallographic structure, surface morphology, chemical composition, and electrical and decorative properties of the films on the annealing temperature was investigated. X-ray diffraction showed different phases of zirconium oxide at different annealing temperatures. It is observed that crystallite size and nanostrain increase with annealing temperature. Atomic force microscopy results showed granular structure in all samples, while both grain size and film surface roughness increased with the annealing temperature. Energy dispersive X-ray analysis data showed that the ratio of O/Zr was approximately 1.6, 1.7, 1.9, 2.1, and 2.2 at annealing temperatures of 100°C, 200°C, 300°C, 400°C, and 500°C, respectively. The annealed films at higher temperatures (400°C and 500°C) were transparent, while annealed films at lower temperatures (100°C to 300°C) were grey and brown, respectively. The variation of electrical resistance of samples with applied voltage was approximately constant, while it increased with annealing temperature.  

OICC PRESS Improving optical absorptivity of natural dyes for fabrication of efficient dye-sensitized solar cells Volume 7 (2013) Issue 1 2022 12 23 Improving optical absorptivity of natural dyes for fabrication of efficient dye-sensitized solar cells 10.1186/2251-7235-7-57 EN Reza Hemmatzadeh Department of Physics, Faculty of Science, Persian Gulf University Ahmad Mohammadi Department of Physics, Faculty of Science, Persian Gulf University Journal Article 2022 12 23 AbstractEfficient and cheap dye-sensitized solar cells (DSSCs) were fabricated using natural dyes from Pastinaca sativa and Beta vulgaris. Natural dyes are environmentally and economically superior to ruthenium-based dyes because they are nontoxic and cheap. However, the conversion efficiency of dye-sensitized solar cells based on natural dyes is low. One way to improve the DSSC performance is to enhance the absorptivity of extracted dyes. We investigated the influence of various factors in the extraction process, such as utilization of different extraction approaches, the acidity of extraction solvent, and different compounds of solvents on the optical absorption spectra. It was found that we could considerably enhance the optical absorptivity of dye and consequently the performance of DSSC by choosing a proper mixture of ethanol and water for extracting solvent and also the acidity of dye solution.