Toward a theory of the double plasma resonance in the solar corona

Specific features of the double plasma resonance effect in a magnetized plasma of the solar corona are discussed. The effect consists in enhanced generation of plasma waves in the regions where the upper hybrid frequency coincides with electron gyrofrequency harmonics. It is widely used for interpretation of a fine structure in solar radio emission spectrum in the form of parallel drifting quasi-harmonic stripes of enhanced radiation intensity (zebra pattern). It is shown that the plasma-wave growth rate increases due to both dispersion properties of plasma waves, which are determined by the equilibrium plasma component, and electrons which are non-equilibrium with respect to the velocities transverse to the magnetic field. Special attention is given to an incorrect consideration of the double plasma resonance effect in some papers. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 52, No. 2, pp. 95–108, February 2009.     

Physiological Transportation of Casson Fluid in a Plumb Duct

This paper is devoted to a study of the peristaltic motion of a Casson fluid of a non-Newtonian fluid accompanied in a horizontai tube.To characterize the non-Newtonian fluid behavior,we have considered the Casson fluid model.Suitable similarity transformations are utilized to transform the governing partial differential momentum into the non-linear ordinary differential equations.Exact analytical solutions of these equations are obtained and are the properties of velocity,pressure and profiles are then studied graphically.     

Peristaltic flow of Sisko fluid in a uniform inclined tube

We have analyzed an incompressible Sisko fluid through an axisymmetric uniform tube with a sinusoidal wave propagating down its walls. The present analysis of non- Newtonian fluid is investigated under the considerations of long wavelength and low Reynolds number approximation. The analytic solution is obtained using （i） the regular perturbation method （ii） the Homotopy analysis method （HAM）. The comparison of both the solutions is presented graphically. The results for the pressure rise, frictional force and pressure gradient have been calculated numerically and the results are studied for various values of the physical parameters of interest, such as α （angle of inclination）, b^＊ （Sisko fluid parameter）, Ф （amplitude ratio） and n （power law index）. Trapping phenomena is discussed at the end of the article.     

Effects of additional Higgs doublets on the Coleman-Weinberg SU(2) × U(1) → U(1)em phase transition

In the standard electroweak theory with a Coleman-Weinberg Higgs doublet, it has been shown that the SU(2) × U(1) → U(1)_em phase transition is driven by chiral symmetry breaking and that a phenomenologically dangerous amount of entropy is produced. We show that the addition of a second, sufficiently heavy Coleman-Weinberg doublet will make the transition go via tunneling and will suppress excessive entropy generation.     

Excitation of nonlinear surface modes by wave beams

We consider the interaction of 2-D and 3-D wave beams with an interface between linear and nonlinear media. The range of parameters of Gaussian beams exciting nonlinear surface waves (NSW) with high efficiency is analytically determined. Different regimes of NSW excitation are numerically studied. Analytical data are in good agreement with numerical results.Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 38, Nos. 3–4, pp. 246–255, March–April, 1995.     

Sorption Studies of Nickel ions Onto Sawdust of Dalbergia Sissoo

Sawdust of Dalbergia sissoo, a byproduct of sawmills, was found to be a promising adsorbent for the removal of nickel ions from aqueous solution. Sorption of nickel ions onto sawdust of Dalbergia sissoo was studied using the batch technique. Kinetics studies show that nickel ions sorption process obeys a first order rate law. The applicability of the Langmuir and Freundlich models for the data was tested. Both the models adequately describe the experimental data of the biosorption of nickel ions. The sorption capacities and energies were calculated. Langmuir parameters X_m and K₁ were found to increase with rise in temperature; Freundlich constants 1/n and K_f have been evaluated for 293K, 303K, 313K and 323K. Thermodynamic parameter ΔH° = 4.80 kJ mol^?;1 shows that sorption of nickel ions onto sawdust is an endothermic process.     

Biodegradability of polylactide bottles in real and simulated composting conditions

As new biodegradable polymers and their packaging applications are emerging, there is a need to address their environmental performance. In particular, there is a need to understand the time required for their complete disintegration, before these materials are deployed in commercial composting processes. Standards developed by ASTM and ISO evaluate the biodegradation of biodegradable plastic materials in simulated controlled composting conditions. However, a more detailed understanding of the biodegradation of complete packages is needed in order to have a successful composting operation. This paper investigates the biodegradation performance of polylactide (PLA) bottles under simulated composting conditions according to ASTM and ISO standards, and these results are compared with a novel method of evaluating package biodegradation in real composting conditions. Two simulated composting methods were used in this study to assess biodegradability of PLA bottles: (a) a cumulative measurement respirometric (CMR) system and (b) a gravimetric measurement respirometric (GMR) system. Both CMR and GMR systems showed similar trends of biodegradation for PLA bottles and at the end of the 58th day the mineralization was 84.2±0.9% and 77.8±10.4%, respectively. PLA bottle biodegradation in real composting conditions was correlated to their breakdown and variation in molecular weight. Molecular weight of 4100 Da was obtained for PLA bottles in real composting conditions on the 30th day. The biodegradation observed for PLA bottles in both conditions explored in this study matches well with theoretical degradation and biodegradation mechanisms; however, biodegradation variability exists in both conditions and is discussed in this paper.     

Au Nanoparticles Supported Nanoporous ZnO Sphere for Enhanced Photocatalytic Activity Under UV-Light Irradiation

Monodispersed 200 nm-sized ZnO spheres (SPs) with porous structure emanating from 8 nm zinc oxide nanoparticles (NPs) composing the SPs were synthesized by dissolving zinc acetate dihydrate in diethylene glycol at 160 °C. The prepared SPs were employed in fabricating the gold (Au) loaded ZnO (Au/ZnO SP) composite materials, exhibiting high photocatalytic activity in decomposing salicylic acid under UV-light irradiation. It is deduced that its high catalytic activity originates from the charge separation by transferring photoinduced electrons from the conduction band (CB) of ZnO to Au, since the CB level of ZnO (?0.5 V vs. NHE) is located more negative side than that of Au (+0.5 V vs. NHE). The evidence for the charge separation was provided by monitoring^.OH radical with bare ZnO SPs and Au/ZnO SP produced in the solution which readily react with 1,4-terephthalic acid (TA) inducing 2-hydroxy terephthalic acid (TAOH) that shows unique fluorescence peak at 426 nm.