bluuebunny/crossref_metadata_2025 huggingface dataset:
Oscillatory Screening Effects on Elastic Collisions in Dense Electron-Ion Quantum Plasmas
Authors: Koo Yo-Han , Jung Young-Dae
Published: February 2015

The oscillatory screening effects on elastic electron-ion collisions are investigated in dense quantum plasmas. The eikonal method with the modified Debye-Hückel potential is employed to obtain the scattering phase shift and scattering amplitude. In addition, the total elastic collision cross section is obtained by the optical theorem with the forward scattering amplitude in quantum plasmas. It is shown that the modified Debye-Hückel screening in quantum plasmas produces the oscillatory behaviour of the scattering phase shift. In addition, the minimum position of the phase shift is receded from the target ion with decreasing the quantum wave number. It is also found that the oscillatory screening effect suppresses the differential cross section. The total cross section is also found to be decreased due to the oscillatory screening effect. In addition, it is shown that the total cross section decreases with an increase of the quantum wave number
Electrocapillary Curves for the Hg/Ionic Liquid Interface
Authors: Lewandowski Andrzej , Majkowski Tomasz , Galinski Maciej
Published: February 2015

Electrocapillary curves (surface tension γ as a function of the electrode potential E) for a series of room-temperature ionic liquids (RTILs) were measured using a mercury dropping electrode with the drop-weight (drop-volume) technique. The curves γ = f (E) for the Hg/RTIL interface have one maximum and may be approximated with a polynomial of sixth-order. There are no ‘humps’ in the curves. The interfacial tension of the Hg/RTIL system changes with potential E in a monotonic way. The second derivative of γ = f (E) leads to a polynomial of fourth order, indicating the capacitance of the Hg/RTIL interface. The potential of zero charge is within a relatively narrow range. The specific capacitance at the minimum is of the order 10 μF/cm2
Preparation of Some Novel Copper(I) Complexes and their Molar Conductances in Organic Solvents
Authors: Gill Dip Singh , Rana Dilbag
Published: February 2015

Attempts have been made to prepare some novel copper(I) nitrate, sulfate, and perchlorate complexes. Molar conductances of these complexes have been measured in organic solvents like acetonitrile (AN), acetone (AC), methanol (MeOH), N,N-dimethylformamide (DMF), N,Ndimethylacetamide (DMA), and dimethylsulfoxide (DMSO) at 298 K. The molar conductance data have been analyzed to obtain limiting molar conductances (λ0) and ion association constants (KA) of the electrolytes. The results showed that all these complexes are strong electrolytes in all organic solvents. The limiting ionic molar conductances (λo

±
) for various ions have been calculated using Bu4NBPh4 as reference electrolyte. The actual radii for copper(I) complex ions are very large and different in different solvents and indicate some solvation effects in each solvent system
Darboux Transformation and Symbolic Computation on Multi-Soliton and Periodic Solutions for Multi-Component Nonlinear Schr¨odinger Equations in an Isotropic Medium
Authors: Zhang Hai-Qiang , Xu Tao , Li Juan , Li Li-Li , Zhang Cheng , Tian Bo
Published: February 2015

The Darboux transformation is applied to a multi-component nonlinear Schr¨odinger system, which governs the propagation of polarized optical waves in an isotropic medium. Based on the Lax pair associated with this integrable system, the formula for the n-times iterative Darboux transformation is constructed in the form of block matrices. The purely algebraic iterative algorithm is carried out via symbolic computation, and two different kinds of solutions of practical interest, i. e., bright multi-soliton solutions and periodic solutions, are also presented according to the zero and nonzero backgrounds.
Time Evolution of Folded (2+1)-Dimensional Solitary Waves
Authors: Ma Song-Hua , Lu Yi-Pin , Fang Jian-Ping , Lv Zhi-Jie
Published: February 2015

With an extended mapping approach and a linear variable separation approach, a series of solutions (including theWeierstrass elliptic function solutions, solitary wave solutions, periodic wave solutions and rational function solutions) of the (2+1)-dimensional modified dispersive water-wave system (MDWW) is derived. Based on the derived solutions and using some multi-valued functions, we find a few new folded solitary wave excitations.
Nonlinear Models for Relativity Effects in Electromagnetism
Authors: Devasia Santosh
Published: February 2015

Experimental energy measurements tend to be smaller than the predicted values in (i) the absorption of high-energy particles (in cloud chambers) and (ii) the average energy determination of the classical β -ray spectrum of radium E (using magnetic fields). To address these differences in energy measurements, we reconsider relative-velocity-dependent models in electromagnetism proposed initially by Weber before data from cathode-ray-tube (CRT) experiments was available. It is shown that identifying the nonlinear, relative-velocity terms using CRT data results in a model, which (i) captures relativity effects in optics and high-energy particles, and (ii) explains the apparent discrepancies in experimental energy measurements.
Crystallization Kinetics Study on Orthogonal Ordering in N-(p-n-Alkyoxybenzylidene)-p-n-Alkylanilines (nO.m Compounds) by Thermal and Electrical Techniques. Part I
Authors: Chitravel Thangaiyan , Madhu Mohan Mathukumalli Lakshmi Nasayana , Krishnakumar Varadarajan
Published: February 2015

A systematic kinetic study of crystallization among two smectogens of higher homologues of the benzylidene aniline series nO.m, viz. 4O.12 and 8O.12, has been carried out by thermal microscopy, differential scanning calorimetry (DSC), and dielectric studies. The crystallization kinetics was studied by two techniques, viz. the traditional thermal analysis, i. e. DSC, and electrical studies, i. e. capacitance and dielectric loss variation measurements with temperature. The DSC thermograms were run from the crystallization temperature to the isotropic melting temperature for different time intervals. The liquid crystalline behaviour together with the rate of crystallization of smectic ordering in newly synthesized nO.m compounds were discussed in relation to the kinetophase (which occurs prior to crystallization). The molecular mechanism and dimensionality of crystal growth were computed using the Avrami equation. The characteristic crystallization time (t∗) at each crystallization temperature was deduced from the individual plots of logtand ΔH. Further, it was observed that the data obtained from DSC and dielectric studies were in good agreement.
Kelvin-Helmholtz and Rayleigh-Taylor Instability of Two Superimposed Magnetized Fluids with Suspended Dust Particles
Authors: Prajapati Ramprasad , Das Soni  , Sanghvi Raj Kamal , Chhajlani Rajendra Kumar
Published: February 2015

The effect of a magnetic field and suspended dust particles on both the Kelvin-Helmholtz (K-H) and the Rayleigh-Taylor (R-T) instability of two superimposed streaming magnetized plasmas is investigated. The magnetized fluids are assumed to be incompressible and flowing on top of each other. The usual magnetohydrodynamic (MHD) equations are considered with suspended dust particles. The basic equations of the problem are linearized and the dispersion relation is obtained using normal mode analysis by applying the appropriate boundary conditions. The general dispersion relation is found to be modified due to the presence of the suspended dust particles and of the magnetic field. The effect of the magnetic field appears in the dispersion relation if three-dimensional perturbations of the system are considered. The general conditions of the K-H instability as well as the R-T instability are derived for the considered medium. The stability of the system for both cases is discussed by applying the Routh-Hurwitz criterion. Numerical analysis is performed to show the effect of various parameters on the growth rates of the K-H and R-T instabilities. Three different cases of the present configurations are considered and the conditions of instability are obtained. It is found that the conditions for the K-H and R-T instabilities depend on the magnetic field, on the suspended dust particles and on the relaxation frequency of the particles. The magnetic field and particle density have stabilizing influence, while the density difference between the fluids has a destabilizing influence on the growth rate of the K-H and R-T configurations.
Multivariate Analysis for Chemistry-Property Relationships in Molten Salts
Authors: Suh Changwon , Gadzuric Slobodan , Gaune-Escard Marcelle , Rajan Krishna
Published: February 2015

We systematically analyze the molten salt database of Janz to gain a better understanding of the relationship between molten salts and their properties. Due to the multivariate nature of the database, the intercorrelations amongst the molten salts and their properties are often hidden and defining them is challenging. Using principal component analysis (PCA), a data dimensionality reduction technique, we have effectively identified chemistry-property relationships. From the various patterns in the PCA maps, it has been demonstrated that information extracted with PCA not only contains chemistryproperty relationships of molten salts, but also allows us to understand bonding characteristics and mechanisms of transport and melting, which are difficult to otherwise detect.
Nanoparticulate Dye-Semiconductor Hybrid Materials Formed by Electrochemical Self-Assembly as Electrodes in Photoelectrochemical Cells
Authors: Nonomura Kazuteru , Loewenstein Thomas , Michaelis Esther , Kunze Peter , Schiek Manuela , Reemts Jens , Yoshie Iwaya Mirian , Wark Michael , Rathousky Jiri , Al-Shamery Katharina , Kittel Achim , Parisi Jürgen , Wöhrle Dieter , Yoshida Tsukasa , Schlettwein Derck
Published: February 2015

Dye-sensitized zinc oxide thin films were prepared, characterized and optimized for applications as photoelectrochemically active electrodes. Conditions were established under which crystalline thin films of ZnO with a porous texture were formed by electrochemically induced crystallization controlled by structure-directing agents (SDA). Dye molecules were adsorbed either directly as SDA during this preparation step or, preferably, following desorption of a SDA. The external quantum efficiency (IPCE) could thereby be increased significantly. Particular emphasis was laid on dye molecules that absorb in the red part of the visible spectrum. Model experiments under ultrahigh vacuum (UHV) conditions with dye molecules adsorbed on defined crystal planes of single crystals aimed at a deeper understanding of the coupling of the chromophore electronic π-system within molecular aggregates and to the semiconductor surface. Detailed photoelectrochemical kinetic measurements were used to characterize and optimize the electrochemically prepared dye-sensitized ZnO films. Parallel electrical characterization in vacuum served to distinguish between contributions of charge transport within the ZnO semiconductor matrix and the ions of the electrolyte in the pore system of the electrode.
The Analytical Solutions for Magnetohydrodynamic Flow of a Third Order Fluid in a Porous Medium
Authors: Hayat Tasawar , Ellahi Rahmat , Mahomed Fazal Mehmood
Published: February 2015

An analysis has been carried out for flow and heat transfer characteristics in a third grade fluid between two porous plates. The electrically conducting fluid fills the porous medium. The solutions have been developed for small porosity and magnetic field. Three flow problems are investigated and analytical expressions for the velocity field and temperature distribution are given for each case. Moreover, we recover and extend the results of Siddiqui et al. [1] by presenting exact solutions for the governing equations derived in [1].
Peristaltic Transport of a Hyperbolic Tangent Fluid Model in an Asymmetric Channel
Authors: Nadeem Sohail , Akram Safia
Published: February 2015

In the present analysis, we have modeled the governing equations of a two dimensional hyperbolic tangent fluid model. Using the assumption of long wavelength and low Reynolds number, the governing equations of hyperbolic tangent fluid for an asymmetric channel have been solved using the regular perturbation method. The expression for pressure rise has been calculated using numerical integrations. At the end, various physical parameters have been shown pictorially. It is found that the narrow part of the channel requires a large pressure gradient, also in the narrow part the pressure gradient decreases with the increase in Weissenberg number We and channel width d.
Series Solutions of Boundary Layer Flow of a Micropolar Fluid Near the Stagnation Point Towards a Shrinking Sheet
Authors: Nadeem Sohail , Abbasbandy Saeid , Hussain Majid
Published: February 2015

An analysis has been carried out to obtain the series solution of boundary layer flow of a micropolar fluid towards a shrinking sheet. The governing equations of micropolar fluid are simplified using suitable similarity transformations and then solved by homotopy analysis method (HAM). The convergence of the HAM solutions has been obtained by using homotopy-pade approximation. The effects of various parameters such as porosity parameter R, the ratio λ and the microinertia K on the velocity and microinertia profiles as well as local skin friction coefficient are presented graphically and in tabulated form.
Flow of a Third Grade Fluid between Coaxial Cylinders with Variable Viscosity
Authors: Malik Muhammad Y. , Hussain Azad , Nadeem Sohail , Hayat Tasawar
Published: February 2015

The influence of temperature dependent viscosity on the flow of a third grade fluid between two coaxial cylinders is carried out. The heat transfer analysis is further analyzed. Homotopy analysis method is employed in finding the series solutions. The effects of pertinent parameters have been explored by plotting graphs.
Generalization of He’s Exp-Function Method and New Exact Solutions for Burgers Equation
Authors: Ebaid Abd El-Halim
Published: February 2015

A generalization of He’s Exp-function method for nonlinear equations is introduced in this research. New exact solutions are obtained for Burgers equation
An Approximate Analytical Solution of the Fractional Diffusion Equation with Absorbent Term and External Force by Homotopy Perturbation Method
Authors: Das Subir , Gupta Praveen Kumar
Published: February 2015

In the present paper, the approximate analytical solutions of a general diffusion equation with fractional time derivative in the presence of an absorbent term and a linear external force are obtained with the help of the powerful homotopy perturbation method (HPM). By using initial values, the approximate analytical solutions of the equation are derived. The results are deduced for different particular cases. The numerical results show that only a few iterations are needed to obtain accurate approximate solutions and these are presented graphically. The presented method is extremely simple, concise, and highly efficient as a mathematical tool in comparison with the other existing techniques.
On the Reconstruction of the First Term in the Variational Iteration Method for Solving Differential Equations
Authors: Tatari Mehdi , Dehghan Mehdi
Published: February 2015

The well-known He’s variational iteration method is an efficient and easy technique for finding the solution of various kinds of problems. In this method the solution of a nonlinear problem is found without any need to solve a linear or nonlinear system of equations. In the current work we present an idea for accelerating the convergence of the resulted sequence to the solution of the problem by choosing a suitable initial term. The efficiency of the method will be shown by testing the new algorithm on several examples.
Radiation and Mass Transfer Effects on the Magnetohydrodynamic Unsteady Flow Induced by a Stretching Sheet
Authors: Hayat Tasawar , Qasim Muhammad , Abbas Zaheer
Published: February 2015

This investigation deals with the influence of radiation on magnetohydrodynamic (MHD) and mass transfer flow over a porous stretching sheet. Attention has been particularly focused to the unsteadiness. The arising problems of velocity, temperature, and concentration fields are solved by a powerful analytic approach, namely, the homotopy analysis method (HAM). Velocity, temperature, and concentration fields are sketched for various embedded parameters and interpreted. Computations of skin friction coefficients, local Nusselt number, and mass transfer are developed and examined.
Quantum-Chemical Estimation of Outersphere Cations Influence on Charge Transfer at the NbF7
2– Reduction. I. Electronic Structure of Complexes
Authors: Soloviev Veniamin V. , Chernenko Lyudmila A. , Kremenetsky Vyacheslav G. , Kuznetsov Sergey A.
Published: February 2015

Quantum-chemical calculations of the parameters of the nM+ ・ NbF7
q− type particles, where M stands for Na, K, Cs; q = 2,3 and n = 0 - 7 have been performed. Within the framework of this approximation, compositions for the most stable particles in molten salts were obtained. It is shown that electron transfer onto the particle results in a different redistribution of the electron density with the Na and K-particles on one hand and Cs-containing particles on the other hand. Energies and some other characteristics of the electron structure and particle geometry were determined depending on the n and M values.
Variational Iteration Method for Burgers’ and Coupled Burgers’ Equations Using He’s Polynomials
Authors: Mohyud-Din Syed Tauseef , Noor Muhammad Aslam , Noor Khalida Inayat
Published: February 2015

In this paper, we apply a modified version of the variational iteration method (MVIM) for solving Burgers’ and coupled Burgers’ equations. The proposed modification is made by introducing He’s polynomials in the correction functional of the variational iteration method (VIM). The use of Lagrange multiplier coupled with He’s polynomials are the clear advantages of this technique over the decomposition method.
The Solution of the Regularized Long Wave Equation Using the Fourier Leap-Frog Method
Authors: Hassan Hany N. , Saleh Hassan K.
Published: February 2015

An efficient numerical method is developed for solving nonlinear wave equations by studying the propagation and stability properties of solitary waves (solitons) of the regularized long wave (RLW) equation in one space dimension using a combination of leap frog for time dependence and a pseudospectral (Fourier transform) treatment of the space dependence. Our schemes follow very accurately these solutions, which are given by simple closed formulas. Studying the interaction of two such solitons and three solitary waves interaction for the RLW equation. Our implementation employs the fast Fourier transform (FFT) algorithm.
Analytic Solution of the Sharma-Tasso-Olver Equation by Homotopy Analysis Method
Authors: Abbasbandy Saeid , Ashtiani Mahnaz , Babolian Esmail
Published: February 2015

An analytic technique, the homotopy analysis method (HAM), is applied to obtain the kink solution of the Sharma-Tasso-Olver equation. The homotopy analysis method is one of the analytic methods and provides us with a new way to obtain series solutions of such problems. HAM contains the auxiliary parameter ħwhich gives us a simple way to adjust and control the convergence region of series solution. “Due to this reason, it seems reasonable to rename ħthe convergence-control parameter” [1].
Nematic/Smectic-A Transition (NSA), Location of Tri Critical Point (TCP) in nO.m Series – A Birefringence Study
Authors: Pisipati Venkata G.K. M. , Latha Divi Madhavi , Madhav Boddapati T. P. , Prasad Potapragada V. Datta
Published: February 2015

The tri critical point (TCP), where the second-order transition transforms to first order has been located in nO.m homologous series. The order parameter has been estimated from the birefringence δn, from the refractive indices and from birefringence data available in literature and from those obtained at our laboratory on a number of nO.m compounds. The compounds in the nO.m series exhibit both second and first-order nematic/smectic-A (NSA) transition depending on the McMillan ratio (TNA/TIN) which in turn depends on the nematic and smectic-A thermal ranges. The data presented are compared with the body of the data available on this homologous series obtained with other techniques.
On Exact Solutions for Oscillatory Flows in a Generalized Burgers Fluid with Slip Condition
Authors: Hayat Tasawar , Najam Saher , Sajid Muhammad , Ayub Muhammad , Mesloub Said
Published: February 2015

An analysis is performed for the slip effects on the exact solutions of flows in a generalized Burgers fluid. The flow modelling is based upon the magnetohydrodynamic (MHD) nature of the fluid and modified Darcy law in a porous space. Two illustrative examples of oscillatory flows are considered. The results obtained are compared with several limiting cases. It has been shown here that the derived results hold for all values of frequencies including the resonant frequency.
Mixed Convection Boundary Layer Flow over a Stretching Surface Filled with a Maxwell Fluid in Presence of Soret and Dufour Effects
Authors: Hayat Tasawar , Mustafa Meraj , Mesloub Said
Published: February 2015

This article looks at the heat and mass transfer characteristics in mixed convection boundary layer flow about a linearly stretching vertical surface. An incompressible Maxwell fluid occupying the porous space takes into account the diffusion-thermo (Dufour) and thermal-diffusion (Soret) effects. The governing partial differential equations are transformed into a set of coupled ordinary differential equations, by invoking similarity transformations. The involved nonlinear differential system is solved analytically using the homotopy analysis method (HAM) to determine the convergent series expressions of velocity, temperature, and concentration. The physical interpretation to these expressions is assigned through graphs and tables for the Nusselt number θ '(0) and the Sherwood number φ '(0). The dependence of suction parameter S, mixed convection parameter λ, Lewis number Le, Prandtl number Pr, Deborah number β , concentration buoyancy parameter N, porosity parameter γ , Dufour number Df, and Soret number Sr is seen on the flow quantities.
Periodic Solutions of Asymptotically Linear Hamiltonian Systems without Twist Conditions
Authors: Cheng Rong , Zhang Dongfeng
Published: February 2015

In dynamical system theory, especially in many fields of applications from mechanics, Hamiltonian systems play an important role, since many related equations in mechanics can be written in an Hamiltonian form. In this paper, we study the existence of periodic solutions for a class of Hamiltonian systems. By applying the Galerkin approximation method together with a result of critical point theory, we establish the existence of periodic solutions of asymptotically linear Hamiltonian systems without twist conditions. Twist conditions play crucial roles in the study of periodic solutions for asymptotically linear Hamiltonian systems. The lack of twist conditions brings some difficulty to the study. To the authors’ knowledge, very little is known about the case, where twist conditions do not hold.
Flow by a Porous Shrinking Surface in a Rotating Frame
Authors: Hayat Tasawar , Iram Sania , Javed Tariq , Asghar Saleem
Published: February 2015

We derive series solution of a nonlinear problem which models the magnetohydrodynamic (MHD) shrinking flow due to a porous plate in a rotating frame of reference. The governing partial differential equations are first converted into ordinary differential equations and then solved by homotopy analysis method. The convergence of the derived series solution is carefully analyzed. Graphical results are presented to examine the role of various interesting parameters.
Application of He’s Homotopy Perturbation Method to Fractional Diffusion Equations
Authors: Das Subir , Gupta Praveen Kumar , Pandey Vinod Sankar , Rai Kabindra Nath
Published: February 2015

In this paper, the approximate analytical solutions of a general diffusion equation with fractional time derivative in the presence of a linear external force are obtained with the help of the homotopy perturbation method (HPM). The explicit solutions of the problem for the initial condition as a function of x have been obtained. It reveals that a few iterations are needed to obtain accurate approximate analytical solutions. The numerical calculations are carried out when the initial conditions are like exponential and periodic functions and the results are depicted through graphs. The examples prove that the method is extremely effective due to its simplistic approach and performance.
Homotopy Perturbation Method for a Reliable Analytic Treatment of some Evolution Equations
Authors: Chun Changbum
Published: February 2015

In this paper, we suggest a new reliable application of He’s homotopy perturbation method to study some evolution equations. The new application accelerates the rapid convergence of the series solutions and is used for analytic treatment of these equations. Some illustrative examples are given to further highlight the reliability and flexibility of the homotopy perturbation method.
Application of Homotopy Perturbation Method with Chebyshev Polynomials to Nonlinear Problems
Authors: Chun Changbum
Published: February 2015

In this paper, we present an efficient modification of the homotopy perturbation method by using Chebyshev’s polynomials and He’s polynomials to solve some nonlinear differential equations. Some illustrative examples are given to demonstrate the efficiency and reliability of the modified homotopy perturbation method.
Shock Waves in a Dusty Plasma with Positive and Negative Dust where Ions are Non-Thermal
Authors: Mandal Gurudas , Chatterjee Prasanta
Published: February 2015

A four-component dusty plasma consisting of electrons, ions, and negatively as well as positively charged dust grains has been considered. Shock waves may exist in such a four-component dusty plasma. The basic characteristics of shock waves have been theoretically investigated by employing reductive perturbation technique (RPT). It is found that negative as well as positive shock potentials are present in such dusty plasma. The present results may be useful for understanding the existence of nonlinear potential structures that are observed in different regions of space (viz. cometary tails, lower and upper mesosphere, Jupiter’s magnetosphere, interstellar media, etc).
Contribution of Higher-Order Dispersion to Nonlinear Dust Ion Acoustic Waves in Inhomogeneous Mesospheric Dusty Plasma with Dust Charge Fluctuation
Authors: Attia Mohamed T. , Zahran Mohsen A. , El-Shewy Emad K. , Mowafy Ahmed E.
Published: February 2015

The propagation of dust ion acoustic waves (DIAWs) in a weakly inhomogeneous, weakly coupled, collisionless, and unmagnetized four components dusty plasma are examined. The fluid system considered in this work consists of cold positive ions, cold negatively and positively charged dust particles associated with isothermal electrons. For nonlinear (DIAW) waves, a reductive perturbation method was employed to obtain the variable coefficients Kortewege-de Vries (KdV) equation for the first-order potential. For local inhomogenity, the present system admits the coexistence of rarefactive and compressive solitons. As a matter of fact, when the wave amplitude enlarged, the width and velocity of the wave deviate from the prediction of the KdV equation. It means that we have to extend our analysis to obtain the variable coefficients Kortewege-de Vries (KdV) equation with fifth-order dispersion term. For locally constant parameters, the higher-order solution for the resulting equation has been achieved via what is called perturbation technique. The effects of positive and negative dust charge fluctuations on the higher-order soliton amplitude and width of electrostatic solitary structures are outlined.
Ab Initio Hartree-Fock and Density Functional Theory Study on Molecular Structures, Energies, and Vibrational Frequencies of 2-Amino-3-, 4-, and 5-Nitropyridine
Authors: Sert Yusuf , Ucun Fatih , Böyükata Mustafa
Published: February 2015

The molecular structures, vibrational frequencies, and corresponding vibrational assignments of 2-amino-3-, 4-, and 5-nitropyridine have been calculated by using ab initio Hartree-Fock (HF) and density functional theory (B3LYP) methods with 6-311++G(d,p) basis set level. The calculated vibrational frequencies and optimized geometric parameters (bond lengths and bond angles) were found to be in well agreement with the experimental data. The comparison of the observed and the calculated results showed that the scaled B3LYP method is superior to the scaled HF method for both the vibrational frequencies and the geometric parameters. For well fitting the calculated and the experimental frequencies we used scale factors obtained from the ratio of the frequency values of the strongest peaks in the calculated and the experimental spectra. These obtained scales seem to cause the better agreement of the gained vibrations to the experimental data.
Homotopy Analysis Method for Variable Thermal Conductivity Heat Flux Gage with Edge Contact Resistance
Authors: Aziz Abdul , Khani Farzad , Darvishi Mohammad Taghi
Published: February 2015

The homotopy analysis method (HAM) has been used to develop an analytical solution for the thermal performance of a circular-thin-foil heat flux gage with temperature dependent thermal conductivity and thermal contact resistance between the edge of the foil and the heat sink. Temperature distributions in the foil are presented illustrating the effect of incident heat flux, radiation emission from the foil, variable thermal conductivity, and contact resistance between the foil and the heat sink. The HAM results agree up to four places of decimal with the numerical solutions generated using the symbolic algebra package Maple. This close comparison vouches for the high accuracy and stability of the analytic solution.
A Numeric Application Using Diffusion Limited Aggregation Model for the Manganese Dendrites
Authors: Bayirli Mehmet , Kockar Hakan
Published: February 2015

Black deposits known as manganese dendrites often mark the surfaces of magnesite ore. These have fractal appearance, but the origin and characteristics properties of this morphology and the numerical computation of its geometry have been little studied. The shapes and fractal properties of the manganese dendrites from several different origins were analysed by means of the formation mechanism and Monte Carlo simulation study. These are obtained by the stick probability concepts from the dendrites to compact patterns as the geometrical structures using the diffusion-limited aggregation model. The fractal dimensions were also computed with the stick probability as the numerical equation. The results of the stick probability parameters are compared with the real and arbitrary simulation data and can be helpful to describe the natural and the experimental dendritic patterns.
Effects of Heat and Mass Transfer on Peristaltic Flow of Carreau Fluid in a Vertical Annulus
Authors: Nadeem Sohail , Akbar Noreen Sher
Published: February 2015

This article is devoted to the study of peristaltic transport of a Carreau fluid in a vertical annulus under the consideration of long wavelength. The flow is investigated in a wave frame of reference moving with the velocity of the wave. Exact solutions have been evaluated for temperature and concentration field, while approximated analytical and numerical solutions are found for the velocity field using (i) the perturbation method and (ii) the shooting method. The effects of various emerging parameters are investigated graphically.
Molecular Association of Tetramethylurea and Chlorobenzene Molecules in Microwave Frequency Range
Authors: Sharma Vimal , Thakur Nagesh
Published: February 2015

The dielectric constant ε´ and dielectric loss ε´´ of the binary mixtures of tetramethylurea (TMU) and chlorobenzene (CB) have been calculated at 9.883 GHz by using standard standing microwave techniques. Gopalakrishna’s single frequency concentration variation method has been used to calculate dipole moment μ and dielectric relaxation time τ for different mole fractions of TMU in the binary mixture at different temperatures of 25 °C, 30 °C, 35 °C, and 40 °C. The variation of dielectric relaxation time with the mole fraction of TMU in the whole concentration range of the binary mixtures was found to be non-monotonic. The solute-solute and solute-solvent type of molecular associations may be proposed based upon above observations. Using Eyring rate equations the energy parameters ΔH, ΔF, and ΔS for the dielectric relaxation process and the viscous flow process have been calculated at the given temperatures. It is found from the comparison of energy parameters that, just like the viscous flow process, the dielectric relaxation process can also be treated as a rate process.
Fictitious-Time Wave-Packet Dynamics in Atomic Systems
Authors: Fabčič Tomaž , Main Jörg , Wunner Günter
Published: February 2015

Gaussian wave packets (GWPs) are well suited as basis functions to describe the time evolution of arbitrary wave functions in systems with non-singular smooth potentials. They are rare in atomic systems on account of the singular behaviour of the Coulomb potential.We present a time-dependent variational method that makes the use of GWPs possible in the description of propagation of quantum states also in these systems. We use a regularization of the Coulomb potential and introduce a fictitious-time coordinate in which the evolution of an initial state can be calculated exactly and analytically for a pure Coulomb potential. Therefore, in perturbed atomic systems variational approximations only arise from those parts of the potentials which deviate from the Coulomb potential. The method is applied to the hydrogen atom in external magnetic and electric fields. It can be adapted to systems with definite symmetries and thus allows for a wide range of applications.
Diffusivity-Mobility Relationship for Heavily Doped Semiconductors with Non-Uniform Band Structures
Authors: Khan Arif , Das Atanu
Published: February 2015

A general relationship between the diffusivity and the mobility in degenerate semiconductors with non-uniform energy band structures has been presented. The relationship is general enough to be applicable to both non-degenerate and degenerate semiconductors. It is suitable for the study of electrical transport in heavily doped semiconductors and semiconductor devices.
Series Solutions for the Peristaltic Flow of a Tangent Hyperbolic Fluid in a Uniform Inclined Tube
Authors: Nadeem Sohail , Akbar Noreen Sher
Published: February 2015

In the present investigation we have studied a tangent hyperbolic fluid in a uniform inclined tube. The governing equations are simplified using long wavelength and low Reynold number approximations. The solutions of the problem in simplified form are calculated with two methods namely (i) the perturbation method and (ii) the homotopy analysis method. The comparison of the solutions show a very good agreement between the two results. At the end of the article the expressions of the pressure rise and the frictional force are calculated with the help of numerical integration. The graphical results are presented to show the physical behaviour of Weissenberg number We, amplitude ratio φ , and tangent hyperbolic power law index n.
On the Conversion of Partial Differential Equations
Authors: Mohyud-Din Syed Tauseef
Published: February 2015

This paper outlines the conversion of partial differential equations (PDEs) into the corresponding ordinary differential equations (ODEs) by a complex transformation which is widely used in the exp-function method. The proposed homotopy perturbation method (HPM) is employed to solve the travelling wave solutions. Several examples are given to reveal the reliability and efficiency of the algorithm.
Exp-Function Method for N-Soliton Solutions of Nonlinear Differential-Difference Equations
Authors: Zhang Sheng , Zhang Hong-Qing
Published: February 2015

In this paper, the exp-function method is generalized to construct N-soliton solutions of nonlinear differential-difference equations. With the aid of symbolic computation, we choose the Toda lattice to illustrate the validity and advantages of the generalized work. As a result, 1-soliton, 2-soliton, and 3-soliton solutions are obtained, from which the uniform formula of N-soliton solutions is derived. It is shown that the exp-function method may provide us with a straightforward and effective mathematical tool for generating N-soliton solutions of nonlinear differential-difference equations in mathematical physics.
Effects of Thermal Radiation on Unsteady Magnetohydrodynamic Flow of a Micropolar Fluid with Heat and Mass Transfer
Authors: Hayat Tasawar , Qasim Muhammad
Published: February 2015

An analysis has been carried out to study the combined effects of heat and mass transfer on the unsteady flow of a micropolar fluid over a stretching sheet. The thermal radiation effects are presented. The arising nonlinear partial differential equations are first reduced to a set of nonlinear ordinary differential equations and then solved by the homotopy analysis method (HAM). Plots for various interesting parameters are presented and discussed. Numerical data for surface shear stress, Nusselt number, and Sherwood number in steady case are also tabulated. Comparison between the present and previous limiting results is given.
Effect of Heat Transfer on Magnetohydrodynamic Axisymmetric Flow Between Two Stretching Sheets
Authors: Hayat Tasawar , Nawaz Muhammad
Published: February 2015

This investigation describes the effects of heat transfer on magnetohydrodynamic (MHD) axisymmetric flow of a viscous fluid between two radially stretching sheets. Navier-Stokes equations are transformed into the ordinary differential equations by utilizing similarity variables. Solution computations are presented by using the homotopy analysis method. The convergence of obtained solutions is checked. Skin friction coefficient and Nusselt number are given in tabular form. The dimensionless velocities and temperature are also analyzed for the pertinent parameters entering into the problem.
Analysis of Diffraction of Dominant Mode in an Acoustic Impedance Loaded Trifurcated Duct
Authors: Ayub Muhammad , Hussain Tiwana Mazhar , Mann Amer Bilad
Published: February 2015

The paper presents the analytical description of diffraction phenomena of sound at the opening of a two dimensional semi-infinite acoustically soft duct. This soft duct is symmetrically located inside an infinite duct with normal impedance boundary conditions in the case where the surface acoustic impedances of the upper and lower infinite plates are different from each other. A matrix Wiener- Hopf equation associated with a new canonical scattering problem is solved explicitly. A new kernel function arose for the problem and has been factorized. The graphical results are also presented which show how effectively the unwanted noise can be reduced by proper selection of different parameters.
Key words: Sound Diffraction; Lined Duct; Integral Transform; Wiener-Hopf Technique; Expansion Coefficients; Pole Removal Technique
Authors: Caglar Bulent , Afsin Beytullah , Eren Erdal , Tabak Ahmet , Cirak Cagri , Cubuk Osman
Published: February 2015

The intercalation of dimethyl sulphoxide (DMSO), pyridine (Py), ethanolamine (Ea), and Nmethyl formamide (NMF) molecules into the kaolinite interlayers led to an appreciable decrease of 3697 cm−1 of the hydroxyl band. The appearance of the peaks at 3662, 3541, and 3504 cm−1 proved that the DMSO species are intercalated between the kaolinite layers through forming H-bonds with internal-surface hydroxyl groups. The intensities of the 942 and 796 cm
-1
bending peaks arising from inner-surface hydroxyls decreased and new vibrational features appeared due to the intercalation of the guest species. The d001 value of pure kaolinite was found at 7.18 A° , and the d001 values were seen at 11.26, 11.62, 10.77, and 10.67 °A for kaolinite-dimethyl sulphoxide (K-DMSO), kaolinite-pyridine (K-Py), kaolinite-ethanolamine (K-EA), and kaolinite-N-methyl formamide (K-NMF) composites, respectively. The endothermic differential thermal analysis (DTA) peaks at a temperature of 108 - 334 ◦C reflected the changes in the physicochemical properties of the intercalated species. The thermal stability increase followed the order of K-Py<K-NMF<K-Ea<K-DMSO. Based on the thermal analysis data, the intercalation ratios of the composites above were determined as 80.0, 40.0, 81.6, and 82.0%, respectively. The specific surface areas are affected by the intercalation geometry of the composites within the gallery spacing. The surface areas of the K-DMSO, K-Py, and K-EA complexes increased whereas the surface area of K-NMF decreased with respect to that of untreated kaolinite.
Application of the Exp-Function Method for Solving Some Evolution Equations with Nonlinear Terms of any Orders
Authors: Ebaid Abdelhalim
Published: February 2015

In this paper, suitable transformations and a so-called exp-function method are used to obtain different types of exact solutions for some nonlinear evolution equations with variable coefficients and nonlinear terms of any orders. The Korteweg-de Vries equation and the Burgers equation with nonlinear terms of any orders are chosen to show how to apply the exp-function method for these kinds of nonlinear equations. These exact solutions are in full agreement with the previous results obtained by Ebaid and by Zhu.
Variational Iteration Method for Delay Differential Equations Using He’s Polynomials
Authors: Mohyud-Din Syed Tauseef , Yildirim Ahmet
Published: February 2015

January 21, 2010 In this paper, we apply the variational iteration method using He’s polynomials (VIMHP) for solving delay differential equations which are otherwise too difficult to solve. These equations arise very frequently in signal processing, digital images, physics, and applied sciences. Numerical results reveal the complete reliability and efficiency of the proposed combination.
New Soliton and Periodic Solutions for Two Nonlinear Physical Models
Authors: Chun Changbum , Sakthivel Rathinasamy
Published: February 2015

In this paper, the exp-function method is applied by using symbolic computation to construct a variety of new generalized solitonary and periodic solutions for the Burgers-Kadomtsev-Petviashvili and Vakhnenko equations with distinct physical structures. The results reveal that the exp-function method is very effective and powerful for solving nonlinear evolution equations in mathematical physics.
Travelling Wave Solutions for the Burgers Equation and the Korteweg-de Vries Equation with Variable Coefficients Using the Generalized (G´/G)-Expansion Method
Authors: Zayed Elsayed M. E. , Abdelaziz Mahmoud A. M.
Published: February 2015

In this article, a generalized (G´/G)-expansion method is used to find exact travelling wave solutions of the Burgers equation and the Korteweg-de Vries (KdV) equation with variable coefficients. As a result, hyperbolic, trigonometric, and rational function solutions with parameters are obtained. When these parameters are taking special values, the solitary wave solutions are derived from the hyperbolic function solution. It is shown that the proposed method is direct, effective, and can be applied to many other nonlinear evolution equations in mathematical physics.
Homotopy Perturbation Method for One-Dimensional Hyperbolic Equation with Integral Conditions
Authors: Mohyud-Din Syed Tauseef , Yıldırım Ahmet , Kaplan Yasemin
Published: February 2015

In this study, we use the homotopy perturbation method (HPM) to solve an initial-boundary value problem with a non-classic condition for the one-dimensional wave equation.We will deal with a new type of non-local boundary value problems which are the solution of hyperbolic partial differential equations with a non-standard boundary specification. The method is very reliable and effective and provides the solution in terms of rapid convergent series. Several examples are tested to support our study.
Exact Solutions of Flows of an Oldroyd 8-Constant Fluid with Nonlinear Slip Conditions
Authors: Ellahi Rahmat
Published: February 2015

This communication is concerned with the nonlinear flows of an Oldroyd 8-constant fluid when the no-slip condition is not valid. Due to slip effects in terms of shear stress, the arising slip conditions are nonlinear. The resulting mathematical problems involves nonlinear differential equations and nonlinear boundary conditions. To the best of my knowledge, no such analysis for the flows of an Oldroyd 8-constant fluid is available in the literature. Graphs are plotted for the velocity profiles and examined with respect to the sundry emerging parameters.
A Modified Adomian Decomposition Method for Solving Higher-Order Singular Boundary Value Problems
Authors: Kim Weonbae , Chun Changbum
Published: February 2015

In this paper, we present a reliable modification of the Adomian decomposition method for solving higher-order singular boundary value problems. He’s polynomials are also used to overcome the complex and difficult calculation of Adomian polynomials occurring in the application of the Adomian decomposition method. Numerical examples are given to illustrate the accuracy and efficiency of the presented method, revealing its reliability and applicability in handling the problems with singular nature.
Magnetohydrodynamic Flow and Mass Transfer of a Jeffery Fluid over a Nonlinear Stretching Surface
Authors: Hayat Tasawar , Qasim Muhammad , Abbas Zaheer , Hendi Awatif A.
Published: February 2015

This paper investigates the magnetohydrodynamic (MHD) boundary layer flow of a Jeffery fluid induced by a nonlinearly stretching sheet with mass transfer. The relevant system of partial differential equations has been reduced into ordinary differential equations by employing the similarity transformation. Series solutions of velocity and concentration fields are developed by using the homotopy analysis method (HAM). Effects of the various parameters such as Hartman number, Schmidt number, and chemical reaction parameter on velocity and concentration fields are discussed by presenting graphs. Numerical values of the mass transfer coefficient are also tabulated and analyzed.
Quantum Screening Effects on the Entanglement Fidelity for Elastic Collisions in Electron-Ion Quantum Plasmas
Authors: Ki Dae-Han , Jung Young-Dae
Published: February 2015

The quantum screening effects on the entanglement fidelity for the elastic collision are investigated in electron-ion quantum plasmas. The partial wave analysis and modified Debye-Hückel interaction potential are employed to obtain the entanglement fidelity function in electron-ion quantum plasmas as a function of the collision energy, charge of the ion, and quantum wave number. It is found that the quantum screening effects significantly enhance the entanglement fidelity in electron-ion quantum plasmas. It is also found that the entanglement fidelity increases with an increase of the ion charge. The quantum screening effects on the entanglement fidelity is also found to be increased with increasing plasma density. In addition, it is found that the quantum screening effects decreases with an increase of the collision energy.
Fusion and Annihilation of Solitary Waves for a (2+1)-Dimensional Nonlinear System
Authors: Qiang Ji-Ye , Ma Song-Hua , Ren Qing-Bao , Wang Shao-Hua
Published: February 2015

In this paper, a new projective equation is used to obtain the variable separation solutions with two arbitrary functions of the (2+1)-dimensional Broek-Kaup system (BKK). Based on the derived solitary wave solutions and by selecting appropriate functions, some novel localized excitations such as fusion and annihilation of solitary waves are investigated.