Three-dimensional cylindrical Kadomtsev–Petviashvili equation in a dusty electronegative plasma

2010 ◽  
Vol 76 (3-4) ◽  
pp. 453-466 ◽  
Author(s):  
W. M. MOSLEM ◽  
U. M. ABDELSALAM ◽  
R. SABRY ◽  
E. F. EL-SHAMY ◽  
S. K. EL-LABANY
Keyword(s):  
Three Dimensional ◽  
Negative Ions ◽  
Expansion Method ◽  
Reductive Perturbation Method ◽  
Dust Particles ◽  
Physical Parameters ◽  
New Class ◽  
Electronegative Plasma ◽  
Petviashvili Equation ◽  
Stationary Dust

AbstractThe hydrodynamic equations of positive and negative ions, Boltzmann electron density distribution and Poisson equation with stationary dust particles are used along with the reductive perturbation method to derive a three-dimensional cylindrical Kadomtsev–Petviashvili equation. The generalized expansion method, used to obtain a new class of solutions, admits a train of well-separated bell-shaped periodic pulses. At certain condition, these periodic pulses degenerate to solitary wave solutions. The effects of the physical parameters on the solitary pulses are examined. Finally, the present results should elucidate the properties of ion-acoustic solitary pulses in multi-component plasmas, particularly in Earth's ionosphere.

Ion-acoustic waves in a degenerate multicomponent magnetoplasma

2012 ◽  
Vol 79 (2) ◽  
pp. 163-168 ◽  
Author(s):  
U. M. ABDELSALAM ◽  
M. M. SELIM
Keyword(s):  
Solitary Waves ◽  
Acoustic Waves ◽  
Three Dimensional ◽  
Negative Ions ◽  
Expansion Method ◽  
Reductive Perturbation Method ◽  
Negative Ion ◽  
Zk Equation ◽  
Ion Acoustic ◽  
Astrophysical Objects

AbstractThe hydrodynamic equations of positive and negative ions, degenerate electrons, and the Poisson equation are used along with the reductive perturbation method to derive the three-dimensional Zakharov–Kuznetsov (ZK) equation. The G′/G-expansion method is used to obtain a new class of solutions for the ZK equation. At certain condition, these solutions can describe the solitary waves that propagate in our plasma. The effects of negative ion concentrations, the positive/negative ion cyclotron frequency, as well as positive-to-negative ion mass ratio on solitary pulses are examined. Finally, the present study might be helpful to understand the propagation of nonlinear ion-acoustic solitary waves in a dense plasma, such as in astrophysical objects.

Solitary waves in a dusty adiabatic electronegative plasma

2010 ◽  
Vol 76 (3-4) ◽  
pp. 409-418 ◽  
Author(s):  
A. A. MAMUN ◽  
K. S. ASHRAFI ◽  
M. G. M. ANOWAR
Keyword(s):  
Solitary Waves ◽  
Vries Equation ◽  
Negative Ions ◽  
Finite Amplitude ◽  
Reductive Perturbation Method ◽  
Charged Dust ◽  
Electronegative Plasma ◽  
Ion Acoustic ◽  
Basic Features ◽  
Electronegative Plasmas

AbstractThe dust ion-acoustic solitary waves (SWs) in an unmagnetized dusty adiabatic electronegative plasma containing inertialess adiabatic electrons, inertial single charged adiabatic positive and negative ions, and stationary arbitrarily (positively and negatively) charged dust have been theoretically studied. The reductive perturbation method has been employed to derive the Korteweg-de Vries equation which admits an SW solution. The combined effects of the adiabaticity of plasma particles, inertia of positive or negative ions, and presence of positively or negatively charged dust, which are found to significantly modify the basic features of small but finite-amplitude dust-ion-acoustic SWs, are explicitly examined. The implications of our results in space and laboratory dusty electronegative plasmas are briefly discussed.

Solitary and freak waves in superthermal plasma with ion jet

2012 ◽  
Vol 79 (3) ◽  
pp. 287-294 ◽  
Author(s):  
U. M. ABDELSALAM
Keyword(s):  
Solitary Wave Solution ◽  
Kdv Equation ◽  
Ion Beam ◽  
Negative Ions ◽  
Reductive Perturbation Method ◽  
Dust Particles ◽  
Superthermal Electrons ◽  
Plasma Parameters ◽  
Freak Waves ◽  
Superthermal Plasma

AbstractThe nonlinear solitary and freak waves in a plasma composed of positive and negative ions, superthermal electrons, ion beam, and stationary dust particles have been investigated. The reductive perturbation method is used to obtain the Korteweg-de Vries (KdV) equation describing the system. The latter admits solitary wave solution, while the dynamics of the modulationally unstable wavepackets described by the KdV equation gives rise to the formation of freak/rogue excitation described by the nonlinear Schrödinger equation. In order to show that the characteristics of solitary and freak waves are influenced by plasma parameters, relevant numerical analysis of appropriate nonlinear solutions are presented. The results from this work predict nonlinear excitations that may associate with ion jet and superthermal electrons in Herbig–Haro objects.

Dust-ion-acoustic nonlinear waves in a dusty electronegative plasma with vortex-like negative ions

2012 ◽  
Vol 79 (2) ◽  
pp. 233-238 ◽  
Author(s):  
N. ROY ◽  
S. S. DUHA ◽  
A. A. MAMUN
Keyword(s):  
Nonlinear Waves ◽  
Negative Ions ◽  
Reductive Perturbation Method ◽  
Charge Fluctuation ◽  
Ion Dynamics ◽  
Electronegative Plasma ◽  
Dust Charge ◽  
Positive Ions ◽  
Basic Features ◽  
Positive Ion

AbstractThe basic features of the nonlinear waves, which are associated with positive ion dynamics and dust charge fluctuation, have been investigated by employing the reductive perturbation method in a dusty electronegative plasma containing Boltzmann electrons, vortex-like negative ions, mobile positive ions, and charge fluctuating stationary dust (negatively charged). It has been observed that the basic features of the nonlinear waves (viz. amplitude, width, speed, etc.) in the plasma system under consideration have been significantly modified by the trapping parameter (introduced for vortex-like distribution of negative ions). The implications of the results (obtained from this investigation) in space and laboratory experiments have been briefly discussed.

THREE-DIMENSIONAL PERISTALTIC FLOW OF A WILLIAMSON FLUID IN A RECTANGULAR CHANNEL HAVING COMPLIANT WALLS

2014 ◽  
Vol 14 (01) ◽  
pp. 1450002 ◽  
Author(s):  
R. ELLAHI ◽  
ARSHAD RIAZ ◽  
S. NADEEM
Keyword(s):  
Fluid Model ◽  
Rectangular Channel ◽  
Three Dimensional ◽  
Expansion Method ◽  
Peristaltic Flow ◽  
Three Dimensions ◽  
Physical Parameters ◽  
Williamson Fluid ◽  
Eigenfunction Expansion Method ◽  
Compliant Walls

In this study, the mathematical observations for the peristaltic flow of a Williamson fluid model (e.g., chyme) in a cross-section of a rectangular duct having compliant walls were considered. The flow was assumed incompressible and unsteady. The constitutive equations were reduced under the assumptions of low Reynolds number and long wavelength approximations. The resulting dimensionless governing equations were solved using the homotopy perturbation method (HPM) and eigenfunction expansion method. The results obtained were explained graphically. The velocity distribution was plotted for physical parameters both in two and three dimensions. The streamline graphs are presented in the end, which explain the trapping bolus phenomenon. All theoretical and graphical results are then discussed simultaneously.

scholarly journals Potential distribution around a charged dust grain in an electronegative plasma

2010 ◽  
Vol 76 (5) ◽  
pp. 673-676 ◽  
Author(s):  
P. K. SHUKLA ◽  
L. STENFLO
Keyword(s):  
Potential Distribution ◽  
Negative Ions ◽  
Plasma Sheath ◽  
Dust Particles ◽  
Charged Dust ◽  
Electronegative Plasma ◽  
Positive Ions ◽  
Dust Grain ◽  
Bulk Plasma

AbstractThe potential distribution around a charged dust grain in an electronegative plasma is obtained by using the appropriate dielectric susceptibilities for the Boltzmann distributed electrons and negative ions, and for the inertial positive ions that are streaming from the bulk plasma into the electronegative plasma sheath. The existence of oscillatory ion wakefields is shown. Positive ions are trapped/focused in the ion wakefields, and subsequently the negative dust particles are attracted to each other, forming ordered dust structures.

Dust ion-acoustic solitary waves in a magnetized dusty electronegative plasma

2010 ◽  
Vol 77 (1) ◽  
pp. 133-143 ◽  
Author(s):  
M. G. M. ANOWAR ◽  
K. S. ASHRAFI ◽  
A. A. MAMUN
Keyword(s):  
Solitary Waves ◽  
Solitary Wave Solution ◽  
Kdv Equation ◽  
Negative Ions ◽  
Dusty Plasmas ◽  
Finite Amplitude ◽  
Reductive Perturbation Method ◽  
Electronegative Plasma ◽  
Ion Acoustic ◽  
Basic Features

AbstractThe basic features of obliquely propagating dust ion-acoustic (DIA) solitary waves in an adiabatic magnetized dusty electronegative plasma (containing Boltzmann electrons, Boltzmann negative ions, adiabatic positive ions, and negatively charged stationary dust) have been investigated. The reductive perturbation method has been employed to derive the Korteweg–de Vries (KdV) equation which admits a solitary wave solution. The combined effects of ion adiabaticity and external magnetic field (obliqueness), which are found to significantly modify the basic features of the small but finite-amplitude DIA solitary waves, are explicitly examined. The implications of our results in space and laboratory dusty plasmas are briefly discussed.

scholarly journals Three-Dimensional Rogue Waves in Earth’s Ionosphere

Galaxies ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 48
Author(s):  
Wael F. El-Taibany ◽  
Nabila A. El-Bedwehy ◽  
Nora A. El-Shafeay ◽  
Salah K. El-Labany
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Acoustic Waves ◽  
Modulational Instability ◽  
Three Dimensional ◽  
Negative Ions ◽  
Rogue Waves ◽  
Physical Parameters ◽  
Electrons And Positrons ◽  
Ion Acoustic

The modulational instability of ion-acoustic waves (IAWs) in a four-component magneto-plasma system consisting of positive–negative ions fluids and non-Maxwellian (r,q) distributed electrons and positrons, is investigated. The basic system of fluid equations is reduced to a three-dimensional (3D) nonlinear Schrödinger Equation (NLS). The domains of the IAWs stability are determined and are found to be strongly affected by electrons and positrons spectral parameters r and q and temperature ratio Tp/Te (Tp and Te are positrons and electrons temperatures, respectively). The existence domains, where we can observe the ion-acoustic rogue waves (IARWs) are determined. The basic features of IARWs are analyzed numerically against the distribution parameters and the other system physical parameters as Tp/Te and the external magnetic field strength. Moreover, a comparison between the first- and second-order rogue waves solution is presented. Our results show that the nonlinearity of the system increases by increasing the values of the non-Maxwellian parameters and the physical parameters of the system. This means that the system gains more energy by increasing r, q, Tp, and the external magnetic field through the cyclotron frequency ωci. Finally, our theoretical model displays the effect of the non-Maxwellian particles on the MI of the IAWs and RWs and its importance in D–F regions of Earth’s ionosphere through (H+,O2−) and (H+,H−) electronegative plasmas.

A Peptoid with Extended Shape in Water

2019 ◽  
Author(s):  
Jumpei Morimoto ◽  
Yasuhiro Fukuda ◽  
Takumu Watanabe ◽  
Daisuke Kuroda ◽  
Kouhei Tsumoto ◽  
...  
Keyword(s):  
Spectroscopic Analysis ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Biomolecular Recognition ◽  
Biological Application ◽  
New Class ◽  
Proteolytic Resistance ◽  
Pharmacokinetic Properties ◽  
Optically Pure ◽  
Three Dimensional Space

<div> <div> <div> <p>“Peptoids” was proposed, over decades ago, as a term describing analogs of peptides that exhibit better physicochemical and pharmacokinetic properties than peptides. Oligo-(N-substituted glycines) (oligo-NSG) was previously proposed as a peptoid due to its high proteolytic resistance and membrane permeability. However, oligo-NSG is conformationally flexible and is difficult to achieve a defined shape in water. This conformational flexibility is severely limiting biological application of oligo-NSG. Here, we propose oligo-(N-substituted alanines) (oligo-NSA) as a new peptoid that forms a defined shape in water. A synthetic method established in this study enabled the first isolation and conformational study of optically pure oligo-NSA. Computational simulations, crystallographic studies and spectroscopic analysis demonstrated the well-defined extended shape of oligo-NSA realized by backbone steric effects. The new class of peptoid achieves the constrained conformation without any assistance of N-substituents and serves as an ideal scaffold for displaying functional groups in well-defined three-dimensional space, which leads to effective biomolecular recognition. </p> </div> </div> </div>

Sign in / Sign up

Export Citation Format

Share Document