This paper concerns with the modeling and construction of a fifth order method for two dimensional acoustic wave equation in heterogenous media. The method is based on a standard discretization of the problem on smooth regions and a nonstandard method for nonsmooth regions. The construction of the nonstandard method is based on the special treatment of the interface using suitable jump conditio...

The characteristics of arbitrary amplitude dust ion acoustic solitary waves (DIASWs) are studied in unmagnetized dusty plasmas whose constituents are cold uid ions, nonextensive electrons and stationary negative/positive dust particles. The pseudopotential approach has been used to investigate the structure of localized waves. It is found that, solitary waves exist in a definite interval for th...

Electrostatic dust-acoustic shock waves are investigated in a viscous, complex plasma consisting of dust particles, electrons, and ions. The system is modelled using the generalized hydrodynamic equations, with strong coupling between the dust particles being accounted for by employing the effective electrostatic temperature approach. Using a reductive perturbation method, it is demonstrated th...

Sawdust a timber waste has been used as a bio-sorbent for the removal of a cationic dye, malachite green from aqueous solutions. The process of removal has been optimized for different parameters like initial concentration of dye solution and contact time, pH, adsorbent dose, and temperature. pHzpc of the adsorbent was determined. Elemental analysis of the adsorbent was carried out. FTIR was pe...

Nonlinear self-modulation of the dust acoustic waves is studied, in the presence of non-thermal (non-Maxwellian) ion and electron populations. By employing a multiple scale technique, a nonlinear Schrödinger-type equation (NLSE) is derived for the wave amplitude. The influence of non-thermality, in addition to obliqueness (between the propagation and modulation directions), on the conditions fo...

Ion acoustic waves can be excited by electrons drifting relative to the ions in a plasma. This relative drift can be produced, in a collisional plasma, by a static electric field. In the analysis of this instability, which occurs for frequencies well below the ion plasma frequency, the electron inertia term in the momentum equation is typically neglected. A similar assumption has been employed ...

The efficiency of two methods of pretreatment (NaOH and H2O2) on lignocelluloses-saw dust, wheat straw, sugarcane bagasse and rice bran-was compared in the present study. Alkali treatment of lignocelluloses relatively removed more hemicelluloses and lignin leaving behind cellulose content in the residues than peroxide treatment. Crude cellulase of Aspergillus niger, produced on the pretreated s...

Novel properties introduced by charged particulates in a plasma medium and how they influence excitation and propagation of waves are discussed. Such a medium, commonly known as dusty plasma, is generated in the near Earth environment by dust and other debris of meteoric origin and exhausts and effluents from space platforms. A novel feature of dusty plasma is that the charge to mass ratio can ...