Abstract: Using pseudo potential method arbitrary amplitude ion-acoustic solitary waves have been theoretically studied in a collisionless plasma consisting of warm drifting positive ions, Boltzmann positrons and nonthermal electrons. Ion-acoustic solitary wave solutions have been obtained and the dependence of the solitary wave profile on different plasma parameters has been studied numerically. Lower and higher order compressive and rarefactive solitary waves are observed in presence of positrons, nonthermal electrons, ion drift velocity and finite ion temperature. Inclusion of higher order nonlinearity is shown to have significant correction to the solitary wave profile for the same values of plasma parameters.
Abstract: The effect of nonthermal pulsed electric field (PEF) and thermal treatment (90⁰C for 60s) was studied on quality parameters of emblica officinalis juice for the period of 6 weeks at 4⁰C using monopolar rectangular pulse of 1µs width. The PEF treatment was given using static chamber at 24kV/cm for 500µs. The quality of emblica officinalis juice was investigated in terms of non enzymatic browning index (NEBI), 5-hydroxymethyl-2-furfural (HMF), total polyphenol content and antioxidant capacity. ⁰Brix, pH and conductivity were evaluated as physical parameters. The aim of the work was to investigate the effect of PEF on the retention of bioactive compounds and retardation of browning activity. The results showed that conventional thermal treatment had led to a significant (p < 0.05) decrease of 48.15% in polyphenol content (129.56 mg of GAE L-1), with higher NEBI and HMF formation (p < 0.05) whilst PEF suppressed NEBI and retained higher polyphenol compounds (168.59 mg GAE L-1) with limiting the loss to 32.56% along maximum free radical scavenging activity (92.07%). However, pH, ⁰brix and electrical conductivity of treated juice samples remain unaffected. Therefore, PEF can be considered as an effective nonthermal treatment for retaining bioactive compounds along suppressing browning of emblica juice.
Abstract: The Constraints imposed by non-thermal
leptogenesis on the survival of the neutrino mass models describing
the presently available neutrino mass patterns, are studied
numerically. We consider the Majorana CP violating phases coming
from right-handed Majorana mass matrices to estimate the baryon
asymmetry of the universe, for different neutrino mass models
namely quasi-degenerate, inverted hierarchical and normal
hierarchical models, with tribimaximal mixings. Considering two
possible diagonal forms of Dirac neutrino mass matrix as either
charged lepton or up-quark mass matrix, the heavy right-handed
mass matrices are constructed from the light neutrino mass matrix.
Only the normal hierarchical model leads to the best predictions of
baryon asymmetry of the universe, consistent with observations in
non-thermal leptogenesis scenario.
Abstract: Ion-acoustic solitary waves in a plasma with
nonthermal electrons, thermal positrons and warm ions are
investigated using Sagdeev-s pseudopotential technique. We study
the effects of non-thermal electrons and ion temperature on solitons
and show both negative and positive potential waves are possible.
Abstract: Dust acoustic solitary waves are studied in warm
dusty plasma containing negatively charged dusts, nonthermal ions
and Boltzmann distributed electrons. Sagdeev pseudopotential
method is used in order to investigate solitary wave solutions in the
plasmas. The existence of compressive and rarefractive solitons is
studied.