Physics Research International The latest articles from Hindawi © 2017 , Hindawi Limited . All rights reserved. Rootlike Morphology of ZnO:Al Thin Film Deposited on Amorphous Glass Substrate by Sol-Gel Method Thu, 26 May 2016 06:46:31 +0000 Zinc oxide (ZnO) and aluminum doped zinc oxide (ZnO:Al) thin films have been deposited onto a glass substrate by sol-gel spray coating method at atmospheric pressure. X-ray diffractometer (XRD), scanning electron microscopy (SEM), and UV-Vis spectrophotometer have been used to characterize the films. XRD spectra indicated that all prepared thin films presented the wurtzite hexagonal structure. SEM images exhibited rootlike morphology on the surface of thin films and the shortest root diameter was about 0.219 μm. The UV-Vis absorption spectra exhibited the absorption edges that were slightly shifted to the lower wavelength. From this result, the incorporation of aluminum into the ZnO involved a slight increase in the optical band-gap of films. The optical bands of films were 3.102 eV, 3.115 eV, 3.118 eV, 3.115 eV, 3.109 eV, and 3.109 eV for ZnO, ZnO:Al 2%, ZnO:Al 4%, ZnO:Al 6%, ZnO:Al 8%, and ZnO:Al 10%, respectively. Increase of Al doping concentration in ZnO films contributed to the increase of their optical band-gap which can be explained by the Burstein-Moss effect. Heri Sutanto, Sufwan Durri, Singgih Wibowo, Hady Hadiyanto, and Eko Hidayanto Copyright © 2016 Heri Sutanto et al. All rights reserved. The Investigation of EM Scattering from the Time-Varying Overturning Wave Crest Model by the IEM Thu, 28 Apr 2016 12:48:24 +0000 Investigation of the electromagnetic (EM) scattering of time-varying overturning wave crests is a worthwhile endeavor. Overturning wave crest is one of the reasons of sea spike generation, which increases the probability of false radar alarms and reduces the performance of multitarget detection in the environment. A three-dimensional (3D) time-varying overturning wave crest model is presented in this paper; this 3D model is an improvement of the traditional two-dimensional (2D) time-varying overturning wave crest model. The integral equation method (IEM) was employed to investigate backward scattering radar cross sections (RCS) at various incident angles of the 3D overturning wave crest model. The super phenomenon, where the intensity of horizontal polarization scattering is greater than that of vertical polarization scattering, is an important feature of sea spikes. Simulation results demonstrate that super phenomena may occur in some time samples as variations in the overturning wave crest. Xiao Meng, Li-xin Guo, and Tian-qi Fan Copyright © 2016 Xiao Meng et al. All rights reserved. Polymorphs of Tolfenamic Acids: Stability Analysis Using Cluster Method Mon, 28 Mar 2016 12:06:10 +0000 We report results of the relative stability between form I and form II of tolfenamic acid. By performing systematic cluster calculations at the B3LYP/6-31 level of theory and including the corrections to the dispersion and basis set superposition error, we found that form II is energetically more stable than form I. Furthermore, we found that the formation of dimers has a stabilizing effect compared to individual monomers in the clusters that we have considered. Lee Sin Ang, Mohamed Ismail Mohamed-Ibrahim, and Shukri Sulaiman Copyright © 2016 Lee Sin Ang et al. All rights reserved. Structural and Magnetic Properties of Mn Doped BiFeO3 Nanomaterials Wed, 23 Mar 2016 11:09:33 +0000 Nanocrystalline    materials were synthesized using sol-gel technique. The structural and magnetic properties were investigated in detail. Rietveld analysis from XRD revealed the structural formation of BiFeO3. As the Mn doping concentration was increased, the structure of BiFeO3 changed from rhombohedral to tetragonal. All the M-H loops showed the ferromagnetic behavior in the prepared samples. Magnetization was observed to enhance as the Mn doping concentration was increased. The enhanced magnetization may be due to the collapse of the space modulated spin structure as observed from the structural changes. V. Srinivas, A. T. Raghavender, and K. Vijaya Kumar Copyright © 2016 V. Srinivas et al. All rights reserved. Study of Dielectric Properties and Ultrasonic Attenuation in KDP-Type Ferroelectrics Mon, 21 Mar 2016 06:53:25 +0000 The soft mode dynamical model has been used to study dielectric properties and ultrasonic attenuation in KDP-type ferroelectric crystals. The model Hamiltonian proposed by Blinc and Zeks has been modified by considering lattice anharmonicity up to fourth-order. The correlations appearing in the dynamical equation have been evaluated using double-time thermal retarded Green’s functions method and Dyson’s equation. Without any decoupling, the higher order correlations, appearing in the dynamical equation, have been evaluated using the renormalized Hamiltonian. The expressions for collective frequencies, width, dielectric constant, ultrasonic attenuation, and tangent loss have been calculated. The dielectric properties and ultrasonic attenuation strongly depend on the relaxational mode behavior of stochastic motion of H2PO4 group in KDP-type ferroelectrics. By fitting model values of physical quantities, the temperature dependence of and for different value of four-body coupling coefficient and dielectric constant and loss tangent has been calculated. The calculated and observed results have been found in good agreement. Vijay Singh Bist and Narayan Singh Panwar Copyright © 2016 Vijay Singh Bist and Narayan Singh Panwar. All rights reserved. Magnetoplasmon Excitations at Graphene Vortex Hall Fluid Edge Tue, 23 Feb 2016 12:32:41 +0000 We investigate magnetoplasmon dynamics localized on the edges of graphene vortex Hall fluid. The vortex matter captures an anomalous term that causes vortex localization near fluid boundary and creates a double boundary layer, with being filling factor. The term also has qualitative effect on resonant excitations of edge magnetoplasmons. We found that, for sharp edges under experimental conditions, graphene edge magnetoplasmon (EMP) resonances have similar behavior as in recent experiments. Gradual distinctions arise for smooth edges in the presence of the anomalous term, where a weak EMP peak appears. The second peak becomes well noticed as the smoothness is increased. We identified the resonant mode as an Inter-EMP. It originates from the oscillations of charges in the inner boundary of the double layer. The present observation brings to light the direct cause of Inter-EMP which remained to be detected in graphene experiments. M. Rabiu, S. Y. Mensah, I. Y. Seini, and S. S. Abukari Copyright © 2016 M. Rabiu et al. All rights reserved. Vibration Analysis of Euler-Bernoulli Beams Partially Immersed in a Viscous Fluid Sun, 21 Feb 2016 14:18:42 +0000 The vibrational characteristics of a microbeam are well known to strongly depend on the fluid in which the beam is immersed. In this paper, we present a detailed theoretical study of the modal analysis of microbeams partially immersed in a viscous fluid. A fixed-free microbeam vibrating in a viscous fluid is modeled using the Euler-Bernoulli equation for the beams. The unsteady Stokes equations are solved using a Helmholtz decomposition technique in a two-dimensional plane containing the microbeams cross sections. The symbolic software Mathematica is used in order to find the coupled vibration frequencies of beams with two portions. The frequency equation is deduced and analytically solved. The finite element method using Comsol Multiphysics software results is compared with present method for validation and an acceptable match between them was obtained. In the eigenanalysis, the frequency equation is generated by satisfying all boundary conditions. It is shown that the present formulation is an appropriate and new approach to tackle the problem with good accuracy. Wafik Abassi, Adil El Baroudi, and Fulgence Razafimahery Copyright © 2016 Wafik Abassi et al. All rights reserved. Synthesis of Magnesium Oxide Nanopowder by Thermal Plasma Using Magnesium Nitrate Hexahydrate Wed, 17 Feb 2016 09:28:04 +0000 Magnesium oxide (MgO) nanopowder was synthesized by thermal plasma in a novel thermal DC plasma torch using magnesium nitrate hexahydrate. Magnesium nitrate hexahydrate (Mg(NO3)2·6H2O) was obtained from serpentinite (Mg3Si2O5(OH)4; lizardite) (Halilovskiy array, Orenburg region, Russia). The synthesized samples were characterized by analytical techniques including X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD and TEM characterization studies confirmed that MgO nanopowder obtained has periclase structure with high purity, and the particle sizes vary within the range of 100 nm to 150 nm. We believe that the present work will promote further experimental studies on the physical properties and the applications of MgO nanopowders in the fields such as high-densed ceramics, additives in bactericide, and refractory products. V. Sirota, V. Selemenev, M. Kovaleva, I. Pavlenko, K. Mamunin, V. Dokalov, and M. Prozorova Copyright © 2016 V. Sirota et al. All rights reserved. Analytic Comparison of MHD Squeezing Flow in Porous Medium with Slip Condition Wed, 10 Feb 2016 09:33:07 +0000 The aim of this paper is to compare the efficiency of various techniques for squeezing flow of an incompressible viscous fluid in a porous medium under the influence of a uniform magnetic field squeezed between two large parallel plates having slip boundary. Fourth-order nonlinear ordinary differential equation is obtained by transforming the Navier-Stokes equations. Resulting boundary value problem is solved using Differential Transform Method (DTM), Daftardar Jafari Method (DJM), Adomian Decomposition Method (ADM), Homotopy Perturbation Method (HPM), and Optimal Homotopy Asymptotic Method (OHAM). The problem is also solved numerically using Mathematica solver NDSolve. The residuals of the problem are used to compare and analyze the efficiency and consistency of the abovementioned schemes. Inayat Ullah, M. T. Rahim, Hamid Khan, and Mubashir Qayyum Copyright © 2016 Inayat Ullah et al. All rights reserved. Investigations on Structural and Optical Properties of Hydrothermally Synthesized Zn2SnO4 Nanoparticles Thu, 04 Feb 2016 08:44:42 +0000 Ternary oxide Zn2SnO4 has emerged as a promising material due to its tunable work function, band gap energy, and electric resistivity by simply varying the composition of the material. Zinc stannate nanoparticles were synthesized by green hydrothermal growth technique at 200°C for the reaction time of 24 h using stannic chloride pentahydrate (SnCl4·5H2O) and zinc chloride (ZnCl2) as precursors maintained at pH value of 8. X-ray diffraction analysis confirmed the phase purity and high crystalline nature of the synthesized sample. The estimated crystallite size was about 12.3 nm corresponding to the most prominent plane (311) using Scherrer equation. Morphology of the sample was characterized by SEM analysis, which confirmed the presence of small size nanoparticles. The optical property of synthesized sample was studied by using UV-visible and PL spectroscopy analysis. The derived optical band gap of 3.94 eV was found to be blue shifted as compared to bulk Zn2SnO4 (3.6 eV), which should be attributed to the quantum size effects. Room temperature photoluminescence spectrum showed emission bands at 397 nm and 468 nm. L. Allwin Joseph, J. Emima Jeronsia, M. Mary Jaculine, and S. Jerome Das Copyright © 2016 L. Allwin Joseph et al. All rights reserved. Quantum Analysis on Time Behavior of a Lengthening Pendulum Wed, 03 Feb 2016 13:26:36 +0000 Quantum properties of a lengthening pendulum are studied under the assumption that the length of the string increases at a steady rate. Advanced analysis for various physical problems in several types of quantum states, such as propagators, Wigner distribution functions, energy eigenvalues, probability densities, and dispersions of physical quantities, is carried out using quantum wave functions of the system. In particular, the time behavior of Gaussian-type wave packets is investigated in detail. The probability density for a Gaussian wave packet displaced in the positive at oscillates back and forth from the center (). This phenomenon is very similar to the classical motion of the pendulum. As a consequence, we can confirm that there is a correspondence between its quantum and classical behaviors. When we analyze a dynamical system in view of quantum mechanics, the quantum and classical correspondence is very important in order for the associated quantum theory to be valid and viable. Jeong Ryeol Choi and Ji Nny Song Copyright © 2016 Jeong Ryeol Choi and Ji Nny Song. All rights reserved. Observational Constraints of 30–40 GeV Dark Matter Annihilation in Galaxy Clusters Tue, 26 Jan 2016 12:44:39 +0000 Recently, it has been shown that the annihilation of 30–40 GeV dark matter particles through channel can satisfactorily explain the excess GeV gamma-ray spectrum near the Galactic Center. In this paper, we apply the above model to galaxy clusters and use the latest upper limits of gamma-ray flux derived from Fermi-LAT data to obtain an upper bound of the annihilation cross section of dark matter. By considering the extended density profiles and the cosmic ray profile models of 49 galaxy clusters, the upper bound of the annihilation cross section can be further tightened to  cm3 s−1. This result is consistent with the one obtained from the data near the Galactic Center. Man Ho Chan Copyright © 2016 Man Ho Chan. All rights reserved. Common Pedagogical Issues with De Broglie Waves: Moving Double Slits, Composite Mass, and Clock Synchronization Tue, 01 Dec 2015 09:26:48 +0000 This paper addresses gaps identified in pedagogical studies of how misunderstanding of De Broglie waves affects later coursework and presents a heuristic for understanding the De Broglie frequency of composite. De Broglie’s little known derivation is reviewed with a new illustration based on his description. Simple techniques for reference frame independent analysis of a moving double slit electron interference experiment are not previously found in any literature and cement the concepts. Points of similarity and difference between De Broglie and Schrödinger waves are explained. The necessity of momentum, energy, and wavelength changes in the electrons in order for them to be vertically displaced in their own reference frame is shown to be required to make the double slit analysis work. A relativistic kinematic analysis of De Broglie frequency is provided showing how the higher De Broglie frequency of moving particles is consistent with Special Relativity and time dilation and that it demonstrates a natural system which obeys Einstein’s clock synchronization convention of simultaneity and no other. Students will be better prepared to identify practical approaches to solving problems and to think about fundamental questions. Robert L. Shuler Copyright © 2015 Robert L. Shuler. All rights reserved. A Comparative Study of Spin Coated Transparent Conducting Thin Films of Gallium and Aluminum Doped ZnO Nanoparticles Mon, 16 Nov 2015 08:11:23 +0000 Transparent conducting Ga:ZnO (GZO) and Al:ZnO (AZO) layers have been deposited by spin coating on glass substrates using crystalline nanoparticles redispersed in 1-propanol. The coatings have been sintered in air at 600°C for 15 min and then postannealed in a reducing atmosphere at 400°C for 90 min. The effect of Ga and Al doping on the structural, morphological, optical, and electrical properties of the obtained thin films was investigated. Both films were found to be crystalline with a hexagonal structure. A single step spin coated layer 52–56 nm thick is obtained. To increase the thickness and lower the obtained sheet resistance multilayers coatings have been used. The visible transmission of both layers is high (%). The influence of the sintering temperature and the optimum doping concentration was investigated. Five layers synthesized with doping ratio of 1 mol.% and sintered at 600°C and then submitted to reducing treatment in forming gas exhibited a minimum resistivity value of 7.4 × 10−2 Ω·cm for GZO layer and 1.45 Ω·cm for AZO coating. A. Alkahlout Copyright © 2015 A. Alkahlout. All rights reserved. Nuclear Polymer Explains the Stability, Instability, and Nonexistence of Nuclides Wed, 08 Jul 2015 10:00:00 +0000 Problem. The explanation of nuclear properties from the strong force upwards has been elusive. Approach. Design methods were used to develop conceptual mechanics for the bonding arrangements between nucleons, based on the covert structures for the proton and neutron as defined by the Cordus theory, a type of nonlocal hidden-variable design with discrete fields. Findings. Nuclear bonding arises from the synchronous interaction between the discrete fields of the proton and neutron. This results in not one but multiple types of bond, cis- and transphasic, and assembly of chains and bridges of nucleons into a nuclear polymer. The synchronous interaction constrains the relative orientation of nucleons, and hence the nuclear polymer takes only certain spatial layouts. The stability of nuclides is entirely predicted by morphology of the nuclear polymer and the cis-/transphasic nature of the bonds. The theory successfully explains the qualitative stability characteristics of all hydrogen and helium nuclides. Originality. Novel contributions include the concept of a nuclear polymer and its mechanics; an explanation of the stability, instability, or nonexistence of nuclides starting from the strong/synchronous force; explanation of the role of the neutron. The theory opens a new field of mechanics by which nucleon interactions may be understood. Dirk J. Pons, Arion D. Pons, and Aiden J. Pons Copyright © 2015 Dirk J. Pons et al. All rights reserved. Remaining Problems in Interpretation of the Cosmic Microwave Background Tue, 09 Jun 2015 14:26:21 +0000 By three independent hints it will be demonstrated that still at present there is a substantial lack of theoretical understanding of the CMB phenomenon. One point, as we show, is that at the phase of the recombination era one cannot assume complete thermodynamic equilibrium conditions but has to face both deviations in the velocity distributions of leptons and baryons from a Maxwell-Boltzmann distribution and automatically correlated deviations of photons from a Planck law. Another point is that at the conventional understanding of the CMB evolution in an expanding universe one has to face growing CMB temperatures with growing look-back times. We show, however, here that the expected CMB temperature increases would be prohibitive to star formation in galaxies at redshifts higher than where nevertheless the cosmologically most relevant supernovae have been observed. The third point in our present study has to do with the assumption of a constant vacuum energy density which is required by the present CDM-cosmology. Our studies here rather lead to the conclusion that cosmic vacuum energy density scales with the inverse square of the cosmic expansion scale . Thus we come to the conclusion that with the interpretation of the present-day high quality CMB data still needs to be considered carefully. Hans-Jörg Fahr and Michael Sokaliwska Copyright © 2015 Hans-Jörg Fahr and Michael Sokaliwska. All rights reserved. Structure and Microhardness of Titanium-Based Coatings Formed by Multichamber Detonation Sprayer Mon, 23 Mar 2015 09:15:34 +0000 A series of titanium-based coatings (50–550 μm thick) on an aluminium substrate was deposited via multichamber detonation sprayer with different barrel lengths (300, 400, and 500, all in mm). The titanium-based coatings obtained in these three experiments were examined by optical microscopy, scanning electron microscopy, and X-ray phase analysis. The hardness tests were carried out by the Vickers method with a test load of 50 g. The multichamber detonation sprayer with a barrel length of 500 mm produced the dense layers of coating with hardness of  HV0.05 and porosity of 0.24%, the best result in the experiments. M. Kovaleva, Yu. Tyurin, N. Vasilik, O. Kolisnichenko, M. Prozorova, M. Arseenko, V. Sirota, and I. Pavlenko Copyright © 2015 M. Kovaleva et al. All rights reserved. Dark Energy as a Cosmological Consequence of Existence of the Dirac Scalar Field in Nature Sun, 15 Mar 2015 13:36:28 +0000 The solution of the field equations of the conformal theory of gravitation with Dirac scalar field in Cartan-Weyl spacetime at the very early Universe is obtained. In this theory dark energy (described by an effective cosmological constant) is a function of the Dirac scalar field . This solution describes the exponential decreasing of at the inflation stage and has a limit to a constant value of the dark energy at large time. This can give a way to solving the fundamental cosmological constant problem as a consequence of the fields dynamics in the early Universe. O. V. Babourova and B. N. Frolov Copyright © 2015 O. V. Babourova and B. N. Frolov. All rights reserved. Modified Theories of Gravitation behind the Spacetime Deformation Mon, 02 Mar 2015 09:38:44 +0000 In the framework of proposed theory of spacetime deformation/distortion, we have a way to deform the spacetime through a nontrivial choice of the distortion-complex, displaying different connections, which may reveal different post-Riemannian spacetime structures as corollary. We extend this theory to address, in particular, the gauge model of the most general metric-affine gravity carrying both nontrivial torsion and nonmetricity. This model is constructed in the framework of the first order Lagrangian expressed in terms of the gauge potentials and their first derivatives. The equations of the standard theory, which have no propagating modes for torsion, can be equivalently replaced in modified framework by the modified equations, which in the limit of reducing the affine group leads to the modified Einstein-Cartan theory with dynamical torsion and beyond. In testing the modified framework for various particular cases, we use the Lagrange multipliers for extinguishing nonmetricity and torsion. Gagik Ter-Kazarian Copyright © 2015 Gagik Ter-Kazarian. All rights reserved. Evaluated Excited-State Time-Independent Correlation Function and Eigenfunction of the Harmonics Oscillator Cosine Asymmetric Potential via Numerical Shooting Method Mon, 23 Feb 2015 14:12:06 +0000 We aimed to evaluate the ground-state and excite-state energy eigenvalue (En), wave function, and the time-independent correlation function of the atomic density fluctuation of a particle under the harmonics oscillator Cosine asymmetric potential (Saad et al. 2013). Instead of using the 6-point kernel of 4 Green’s function (Cherroret and Skipetrov, 2008), averaged over disorder, we use the numerical shooting method (NSM) to solve the Schrödinger equation of quantum mechanics system with Cosine asymmetric potential. Since our approach does not use complicated formulas, it requires much less computational effort when compared to the Green functions techniques (Cherroret and Skipetrov, 2008). We show that the idea of the program of evaluating time-independent correlation function of atomic density is underdamped motion for the Cosine asymmetric potential from the numerical shooting method of this problem. Comparison of the time-independent correlation function obtained from numerical shooting method by Boonchui and Hutem (2012) and correlation function experiment by Kasprzak et al. (2008). We show the intensity of atomic density fluctuation in harmonics oscillator Cosine asymmetric potential by numerical shooting method. Artit Hutem and Piyarut Moonsri Copyright © 2015 Artit Hutem and Piyarut Moonsri. All rights reserved. Comparing the Ratchet Effects of Cold Atoms in Periodically Symmetric and Asymmetric Optical Potentials Sat, 31 Jan 2015 07:40:57 +0000 We consider a particle in a spatial symmetric/asymmetric potential driven by time periodic bichromatic AC fields of ratchet type. The associated time-dependent Schrödinger equation is conveniently tackled with the Floquet theory. We next proceed to investigate the ratchet effect induced by the driver, comparing the symmetric with the asymmetric cases. It turns out that the current in the asymmetric case is stronger than that of the symmetric one. Besides, we also investigate the case where the driver is a delta kicked acting on our spatial potential with more emphasis on its chaotic behaviour. Here we check that the current emerges as the phase space is mixed and that the system with asymmetric spatial potential becomes more chaotic than the symmetric one at low kicking strength. Nkongho Ayuketang Arreyndip and Kenfack Anatole Copyright © 2015 Nkongho Ayuketang Arreyndip and Kenfack Anatole. All rights reserved. Liquid Mass Sensing Using Resonating Microplates under Harsh Drop and Spray Conditions Wed, 31 Dec 2014 09:40:57 +0000 We have performed in situ real time mass sensing of deposited liquid volatile droplets and sprays using plate-like microstructures, with robust and reusable performance attained over harsh conditions and multiple cycles of operation. A home-built electrooptical sensing system in ambient conditions has been used. The bimorph effect on the resonant frequency of altered mass loading, elasticity, and strain had been carefully compared, and the latter were found to be negligible in the presence of nonviscous liquids deposited on top of our microplate devices. In resonant mode, the loaded mass has been estimated from measured resonant frequency shifts and interpreted from a simple, uniformly deposited film model. A minimum submicrogram detectable mass was estimated, suggesting the system’s potential for robust, fast, and reusable sensing capabilities, in the presence of volatile liquids under harsh operation conditions. Said Mahajne, Dafne Guetta, Stella Lulinsky, Slava Krylov, and Yoav Linzon Copyright © 2014 Said Mahajne et al. All rights reserved. Modified Hamiltonian Formalism for Regge-Teitelboim Cosmology Sun, 28 Dec 2014 08:35:14 +0000 The Ostrogradski approach for the Hamiltonian formalism of higher derivative theory is not satisfactory because the Lagrangian cannot be viewed as a function on the tangent bundle to coordinate manifold. In this paper, we have used an alternative approach which leads directly to the Lagrangian which, being a function on the tangent manifold, gives correct equation of motion; no new coordinate variables need to be added. This approach can be used directly to the singular (in Ostrogradski sense) Lagrangian. We have used this method for the Regge-Teitelboim (RT) minisuperspace cosmological model. We have obtained the Hamiltonian of the dynamical equation of the scale factor of RT model. Pinaki Patra, Md. Raju, Gargi Manna, and Jyoti Prasad Saha Copyright © 2014 Pinaki Patra et al. All rights reserved. Exact Traveling Wave Solutions for Wick-Type Stochastic Schamel KdV Equation Mon, 15 Dec 2014 00:10:14 +0000 F-expansion method is proposed to seek exact solutions of nonlinear partial differential equations. By means of Hermite transform, inverse Hermite transform, and white noise analysis, the variable coefficients and Wick-type stochastic Schamel KdV equations are completely described. Abundant exact traveling wave solutions for variable coefficients Schamel KdV equations are given. These solutions include exact stochastic Jacobi elliptic functions, trigonometric functions, and hyperbolic functions solutions. Hossam A. Ghany and M. Zakarya Copyright © 2014 Hossam A. Ghany and M. Zakarya. All rights reserved. The Potentially Dangerous Asteroid (101955) Bennu Mon, 15 Dec 2014 00:10:10 +0000 We computed impact solutions of the potentially dangerous asteroid (101955) Bennu based on 569 optical observations from September 11.40624 UTC, 1999 to January 20.11189 UTC, 2013, and 29 radar observations from September 21, 1999, through September 29, 2011. Using the freely available OrbFit software package, we can follow its orbit forward in the future searching for close approaches with the earth, which can lead to possible impacts up to 2200. With the A2 nongravitational parameter in the motion of the asteroid (101955) Bennu we computed possible impact solutions using different JPL planetary and lunar ephemerides and different number of additional massive perturbed asteroids. The possible impact path of risk for 2175 is presented. Additionally, we computed possible impact solutions using the normal places method of the selection of Bennu’s astrometric observations. Moreover, we computed time evolution of the mean orbital elements and the orbital nodes of Bennu 5 kyr in the backwards and 1 kyr in the future using the Yarkovsky effects. We computed the mean motion and secular orbital resonances of the Bennu. We also computed the influence of the JPL planetary and lunar ephemerides DE403, DE405, DE406, DE414, and DE423 on the close approaches of the asteroid (101955) Bennu with the earth. I. Włodarczyk Copyright © 2014 I. Włodarczyk. All rights reserved. Analytical Approximations of Whispering Gallery Modes in Anisotropic Ellipsoidal Resonators Wed, 10 Dec 2014 00:10:32 +0000 Numerical evolutions of whispering gallery modes of both isotropic and anisotropic spheroidal resonators are presented and are used to build analytical approximations of these modes. Such approximations are carried out mainly to have the possibility to have manageable analytic formulas for the eigenmodes and eigenfrequencies of anisotropic resonators. A qualitative analysis of ellipsoidal anisotropic modes in terms of superposition of spherical modes is also presented. Marco Ornigotti and Andrea Aiello Copyright © 2014 Marco Ornigotti and Andrea Aiello. All rights reserved. Electronic Transport Properties of Doped C28 Fullerene Wed, 26 Nov 2014 12:56:23 +0000 Endohedral doping of small fullerenes like C28 affects their electronic structure and increases their stability. The transport properties of Li@C28 sandwiched between two gold surfaces have been calculated using first-principles density functional theory and nonequilibrium Green’s function formalism. The transmission curves, IV characteristics, and molecular projected self-consistent Hamiltonian eigenstates of both pristine and doped molecule are computed. The current across the junction is found to decrease upon Li encapsulation, which can be attributed to change in alignment of molecular energy levels with bias voltage. Akshu Pahuja and Sunita Srivastava Copyright © 2014 Akshu Pahuja and Sunita Srivastava. All rights reserved. Synthesis and Characterization of Screen Printed Zn0.97Cu0.03O Thick Film for Semiconductor Device Applications Mon, 24 Nov 2014 00:00:00 +0000 The studies on doped ZnO thick films deposited over large surface area are still a very promising area of research and development. We report characteristic properties of thick film of Zn0.97Cu0.03O prepared by the economic screen printing technique. The film was characterized by XRD, SEM, diffused reflectance, FTIR, and dark resistivity measurement techniques. The XRD and SEM studies revealed polycrystalline, single phase, porous, and granular surface morphology of this Cu doped ZnO thick films. The direct band gap energy of this film determined by diffuse reflectance technique is 3.18 eV. IR transmission spectrum measured in 4000–600 cm−1 region at ambient temperature confirmed the incorporation of Cu2+ ions in ZnO lattice. The DC resistivity measurements reveal semiconducting nature of the sample with activation energy of 0.66 eV. Rayees Ahmad Zargar, Sharief Ud Din Khan, Mohd Shahid Khan, Manju Arora, and Aurangzeb Khurram Hafiz Copyright © 2014 Rayees Ahmad Zargar et al. All rights reserved. Advancement in Microstructural, Optical, and Mechanical Properties of PVA (Mowiol 10-98) Doped by ZnO Nanoparticles Thu, 20 Nov 2014 00:00:00 +0000 The current paper explores the preparation of PVA nanocomposites by doping with zinc oxide (ZnO) nanoparticles using the method of coagulation and solvent casting technique. The dopant zinc oxide nanoparticle is prepared by simple precipitation method and is confirmed by the X-ray diffraction (XRD) studies. The XRD studies explore that the average particle size of the synthesized nanoparticles is 55 nm and show that the crystallinity factor of PVA nanocomposites is influenced by the interaction occurring between the PVA main chain and the ZnO nanoparticle. The FTIR spectroscopy suggests that the formulation of complexes occurring between the dopants and the PVA main chain is due to inter or intra molecular hydrogen bonding. UV-vis spectra explore the dramatic decrease in the optical energy gap of nanoparticles doped polymer composites and the variations of Urbach energy () related to crystallinity for various dopant concentrations. The mechanical properties of the PVA nanocomposites were explored using universal testing machine (UTM) that reflects that, for % doping concentration, there is an increase in the tensile strength, stiffness, and Young’s modulus, whereas, for % concentration, the percentage total elongation at fracture is found to be the maximum. The morphological behavior and homogenous nanoparticle distribution in the composites were examined by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDAX). N. B. Rithin Kumar, Vincent Crasta, and B. M. Praveen Copyright © 2014 N. B. Rithin Kumar et al. All rights reserved. Retracted: Influence of Magnesium Substitution on Thermal and Electrical Properties of NiCuZn Ferrites for Microinductor Core Applications Thu, 30 Oct 2014 08:30:58 +0000 Physics Research International Copyright © 2014 Physics Research International. All rights reserved.