Published by De Gruyter

Volume 71 Issue 7

Issue of Zeitschrift für Naturforschung A

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Contents
Journal Overview

Publicly Available June 27, 2016

Frontmatter

Page range: i-iii

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Publicly Available May 26, 2016

Decay Mode Solutions for the Supersymmetric Cylindrical KdV Equation

Shufang Deng, Weili Qin, Guiqiong Xu

Page range: 577-581

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Abstract

Supersymmetric cylindrical KdV equation is presented. Decay mode solutions for the supersymmetric KdV equation are derived by supersymmetric Hirota operator.

Publicly Available May 11, 2016

Cooling of Moving Wavy Surface through MHD Nanofluid

Ahmer Mehmood, Muhammad Saleem Iqbal, Irfan Mustafa

Page range: 583-593

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Abstract

Heat transfer analysis has been carried out in the Magnetohydrodynamic (MHD) boundary layer formed near the wavy rough plate moving in x -direction. Due to the presence of metallic nanoparticle in the fluid and enhanced surface area of the plate as a consequence of surface texture, an increase in heat transfer rates is expected. However, the calculation of these enhanced rates of heat transfer is not straightforward because the convection phenomena become more complicated due to the motion of nanoparticle in the base fluid and also the waviness of the plate surface. The contribution of nanoparticle toward convective heat transfer is manifold which requires a suitable model in order to capture the correct physics. Famous Tiwari and Das model has been utilised in the current study. Percent increase in the rate of heat transfer is calculated for the nanoparticle of different metals, such as MWCNT, SWCNT, Al 2 O 3 , TiO 2 and Ag. Appreciable increase in the rate of heat transfer is observed, which is 24% at the most for Al 2 O 3 nanoparticle. The effect of applied magnetic field on the velocity profile, skin friction coefficient, and Nusselt number has also been presented through graphs. The concentration of the nanoparticle has been limited up to 10%.

Publicly Available May 13, 2016

Parallel Plate Flow of a Third-Grade Fluid and a Newtonian Fluid With Variable Viscosity

Volkan Yıldız, Mehmet Pakdemirli, Yiğit Aksoy

Page range: 595-606

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Abstract

Steady-state parallel plate flow of a third-grade fluid and a Newtonian fluid with temperature-dependent viscosity is considered. Approximate analytical solutions are constructed using the newly developed perturbation-iteration algorithms. Two different perturbation-iteration algorithms are used. The velocity and temperature profiles obtained by the iteration algorithms are contrasted with the numerical solutions as well as with the regular perturbation solutions. It is found that the perturbation-iteration solutions converge better to the numerical solutions than the regular perturbation solutions, in particular when the validity criteria of the regular perturbation solution are not satisfied. The new analytical approach produces promising results in solving complex fluid problems.

Publicly Available May 13, 2016

Flow of a Micropolar Fluid Through a Channel with Small Boundary Perturbation

Eduard Marušić-Paloka, Igor Pažanin, Marko Radulović

Page range: 607-619

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Abstract

The aim of this paper is to investigate the effects of small boundary perturbations on the flow of an incompressible micropolar fluid. The fluid domain is described as follows: we start from a simple rectangular domain and then perturb part of its boundary by the product of a small parameter ϵ and some smooth function h . Using formal asymptotic analysis with respect to ϵ , we derive the effective model in the form of the explicit formulae for the velocity, pressure and microrotation. The asymptotic solution clearly acknowledges the effects of the boundary perturbation and the micropolar nature of the fluid. The obtained results are illustrated by some numerical examples confirming that the considered perturbation has a nonlocal impact on the solution.

Publicly Available May 13, 2016

Exact Solutions for Stokes’ Flow of a Non-Newtonian Nanofluid Model: A Lie Similarity Approach

Taha Aziz, A. Aziz, C.M. Khalique

Page range: 621-630

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Abstract

The fully developed time-dependent flow of an incompressible, thermodynamically compatible non-Newtonian third-grade nanofluid is investigated. The classical Stokes model is considered in which the flow is generated due to the motion of the plate in its own plane with an impulsive velocity. The Lie symmetry approach is utilised to convert the governing nonlinear partial differential equation into different linear and nonlinear ordinary differential equations. The reduced ordinary differential equations are then solved by using the compatibility and generalised group method. Exact solutions for the model equation are deduced in the form of closed-form exponential functions which are not available in the literature before. In addition, we also derived the conservation laws associated with the governing model. Finally, the physical features of the pertinent parameters are discussed in detail through several graphs.

Publicly Available May 13, 2016

A New Reduction of the Self-Dual Yang–Mills Equations and its Applications

Yufeng Zhang, Yan Wang

Page range: 631-638

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Abstract

Through imposing on space–time symmetries, a new reduction of the self-dual Yang–Mills equations is obtained for which a Lax pair is established. By a proper exponent transformation, we transform the Lax pair to get a new Lax pair whose compatibility condition gives rise to a set of partial differential equations (PDEs). We solve such PDEs by taking different Lax matrices; we develop a new modified Burgers equation, a generalised type of Kadomtsev–Petviasgvili equation, and the Davey–Stewartson equation, which also generalise some results given by Ablowitz, Chakravarty, Kent, and Newman.

Publicly Available May 26, 2016

Quasi-periodic Solutions to the K(−2, −2) Hierarchy

Lihua Wu, Xianguo Geng

Page range: 639-645

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Abstract

With the help of the characteristic polynomial of Lax matrix for the K (−2, −2) hierarchy, we define a hyperelliptic curve 𝒦 n +1 of arithmetic genus n +1. By introducing the Baker–Akhiezer function and meromorphic function, the K (−2, −2) hierarchy is decomposed into Dubrovin-type differential equations. Based on the theory of hyperelliptic curve, the explicit Riemann theta function representation of meromorphic function is given, and from which the quasi-periodic solutions to the K (−2, −2) hierarchy are obtained.

Publicly Available June 23, 2016

Superposition of Solitons with Arbitrary Parameters for Higher-order Equations

A. Ankiewicz, A. Chowdury

Page range: 647-656

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Abstract

The way in which solitons propagate and collide is an important theme in various areas of physics. We present a systematic study of the superposition of solitons in systems governed by higher-order equations related to the nonlinear Schrödinger family. We allow for arbitrary amplitudes and relative velocities and include an infinite number of equations in our analysis of collisions and superposed solitons. The formulae we obtain can be useful in determining the influence of subtle effects like higher-order dispersion in optical fibres and small delays in the material responses to imposed impulses.

Publicly Available June 16, 2016

Elastic and Thermal Properties of Silicon Compounds from First-Principles Calculations

Haijun Hou, H.J. Zhu, W.H. Cheng, L.H. Xie

Page range: 657-664

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Abstract

The structural and elastic properties of V-Si (V 3 Si, VSi 2 , V 5 Si 3 , and V 6 Si 5 ) compounds are studied by using first-principles method. The calculated equilibrium lattice parameters and formation enthalpy are in good agreement with the available experimental data and other theoretical results. The calculated results indicate that the V-Si compounds are mechanically stable. Elastic properties including bulk modulus, shear modulus, Young’s modulus, and Poisson’s ratio are also obtained. The elastic anisotropies of V-Si compounds are investigated via the three-dimensional (3D) figures of directional dependences of reciprocals of Young’s modulus. Finally, based on the quasi-harmonic Debye model, the internal energy, Helmholtz free energy, entropy, heat capacity, thermal expansion coefficient, Grüneisen parameter, and Debye temperature of V-Si compounds have been calculated.

Publicly Available June 20, 2016

Exact Solutions for N-Coupled Nonlinear Schrödinger Equations With Variable Coefficients

Bo Tang, Yingzhe Fan, Jixiu Wang, Shijun Chen

Page range: 665-672

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Abstract

In this paper, based on similarity transformation and auxiliary equation method, we construct many exact solutions of N -coupled nonlinear Schrödinger equations with variable coefficients, which include soliton solutions, combined soliton solutions, triangular periodic solutions, Jacobi elliptic function solutions and combined Jacobi elliptic function solutions. These solutions may give insight into many considerable physical processes.

Rapid Communication

Publicly Available May 11, 2016

Electrical Conductivity of Molten CdCl₂ at Temperatures as High as 1474 K

Alexander B. Salyulev, Alexei M. Potapov

Page range: 673-675

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Abstract

The electrical conductivity of molten CdCl 2 was measured across a wide temperature range (Δ T =628 K), from 846 K to as high as 1474 K, i.e. 241° above the normal boiling point of the salt. In previous studies, a maximum temperature of 1201 K was reached, this being 273° lower than in the present work. The activation energy of electrical conductivity was calculated.

About this journal

Objective
A Journal of Physical Sciences: Zeitschrift für Naturforschung A (ZNA) is an international scientific journal which publishes original research papers from all areas of experimental and theoretical physics. Authors are encouraged to pay particular attention to a clear exposition of their respective subject, addressing a wide readership. In accordance with the name of our journal, which means “Journal for Natural Sciences”, manuscripts submitted to ZNA should have a tangible connection to actual physical phenomena. In particular, we welcome experiment-oriented contributions.

Manuscripts considered for publication in A Journal of Physical Sciences: Zeitschrift für Naturforschung A undergo high-level refereeing. Mere formal correctness of a paper is not sufficient for its acceptance. Moreover, articles reporting a merely marginal extension of already existing knowledge are considered unsatisfactory. Instead, the key quality a publication in A Journal of Physical Sciences: Zeitschrift für Naturforschung A should possess is that it makes a genuine contribution to the advancement of its topic.

Topics

Atomic, Molecular & Optical Physics
Chemical Physics
Dynamical Systems & Nonlinear Phenomena
Fundamental Concepts of Physical Sciences
Gravitation & Cosmology
Hydrodynamics & Plasma Physics
Nuclear Physics & Particle Physics
Quantum Field Theory
Solid State Physics & Materials Science
Thermodynamics & Statistical Physics
Article formats
Original research articles, research notes, letters and review articles from all areas of theoretical and experimental physics

Information on submission process

Volume 71 Issue 7

Issue of Zeitschrift für Naturforschung A

Frontmatter

Decay Mode Solutions for the Supersymmetric Cylindrical KdV Equation

Abstract

Cooling of Moving Wavy Surface through MHD Nanofluid

Abstract

Parallel Plate Flow of a Third-Grade Fluid and a Newtonian Fluid With Variable Viscosity

Abstract

Flow of a Micropolar Fluid Through a Channel with Small Boundary Perturbation

Abstract

Exact Solutions for Stokes’ Flow of a Non-Newtonian Nanofluid Model: A Lie Similarity Approach

Abstract

A New Reduction of the Self-Dual Yang–Mills Equations and its Applications

Abstract

Quasi-periodic Solutions to the K(−2, −2) Hierarchy

Abstract

Superposition of Solitons with Arbitrary Parameters for Higher-order Equations

Abstract

Elastic and Thermal Properties of Silicon Compounds from First-Principles Calculations

Abstract

Exact Solutions for N-Coupled Nonlinear Schrödinger Equations With Variable Coefficients

Abstract

Electrical Conductivity of Molten CdCl2 at Temperatures as High as 1474 K

Abstract

Electrical Conductivity of Molten CdCl₂ at Temperatures as High as 1474 K