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Varshney M.A.,M B Khalsa College | Shukla S.,Devi Ahilya University | Sen S.,Devi Ahilya University | Sen S.,Indore Institute of Science and Technology | Varshney D.,Devi Ahilya University
Journal of Plasma Physics | Year: 2013

This paper presents the effect of self-focusing on a circularly polarized beam propagating along the static magnetic field when the extraordinary and ordinary modes are present simultaneously for relativistic intensities. The nonlinearity in the dielectric function arises on account of the relativistic variation of mass, which leads to the mutual coupling of the two modes that support the self-focusing of each other. The propagation and focusing of the first mode affects the propagation and focusing of the second mode. The fact that the two modes are laser-intensity dependent leads to cross-focusing. Dynamics of one laser beam affects the dynamics of the second laser beam. When both the beams or modes are strong, the nonlinearities introduced by the relativistic effect in the presence of the magnetic field are additive in nature, such that one beam can undergo oscillatory self-focusing and other beam simultaneously defocusing and vice versa. The dynamical equation governing the cross-focusing has been set up and a numerical solution has been presented for typical relativistic laser-plasma parameters from a slightly underdense to overdense plasma. Copyright © 2013 Cambridge University Press. Source

Varshney D.,Devi Ahilya University | Mansuri I.,Devi Ahilya University | Mansuri I.,Indore Institute of Science and Technology | Khan E.,Devi Ahilya University
Bulletin of Materials Science | Year: 2013

The reported specific heat C (T) data of the perovskite manganites, La 0.85Sr0.15MnO3 and Er0.8Y 0.2MnO3, is theoretically investigated in the temperature domain 3 ≤ T ≤ 50 K. Calculations of C (T) have been made within the three-component scheme: one is the fermion and the others are boson (phonon and magnon) contributions.Lattice specific heat is well estimated fromthe Debye temperature for La0.85Sr0.15MnO3 and E r0.8Y0.2MnO3 manganites. Fermion component as the electronic specific heat coefficient is deduced using the band structure calculations. Later on, following double-exchange mechanism the role of magnon is assessed towards specific heat and found that at much low temperature, specific heat shows almost T3/2 dependence on the temperature. The present investigation allows us to believe that electron correlations are essential to enhance the density of states over simple Fermi-liquid approximation in the metallic phase of both the manganite systems. The present numerical analysis of specific heat shows similar results as those revealed from experiments. © Indian Academy of Sciences. Source

Shaikh M.W.,Devi Ahilya University | Mansuri I.,Devi Ahilya University | Mansuri I.,Indore Institute of Science and Technology | Varshney D.,Devi Ahilya University
AIP Conference Proceedings | Year: 2014

Polycrystalline sample of single-phase La0.8Sm0.05K0.15MnO3 perovskite compound have been synthesized by solid-state reaction route. X-ray diffraction patterns accompanied by Rietveld-refined crystal structure parameters reveal the rhombohedral structure with space group R 3C. Electrical resistivity infers transition from metallic to insulator phase at 537 K. The application of magnetic field of 8 T, suppresses the resistivity. The metallic resistivity is retraced by considering electron-phonon, electron-electron and electron-spin-fluctuation interactions while insulating behaviour is analysed with small polaron conduction model. © 2014 AIP Publishing LLC. Source

Kumar K.A.,Indore Institute of Science and Technology | Krishna A.V.N.,Navodaya Institute of Technology | Shahu Chatrapati K.,Jawaharlal Nehru University
Smart Innovation, Systems and Technologies | Year: 2016

Wireless sensor Network (WSN) is an emerging technology has significant applications in several important fields like military, agriculture, healthcare, environmental, artificial intelligence and research. All these applications demands high quality data transmission from resource constraint WSNs. But interference is one of the severe problem in WSN which can degrade the quality data transmission. Various interference minimization techniques have been proposed but not results the expected degree of quality enhancement in WSNs. This research paper investigates various types of heterogeneous wireless sensor networks (HTWSN) deployment techniques, interference and its effects, existing interference minimization techniques with limitations. We propose interference minimization (IM) protocol for heterogeneous wireless sensor networks. IM protocol can efficiently minimize the interference and enhance the quality data transmission in WSN. © Springer International Publishing Switzerland 2016. Source

Shivhare N.,Indore Institute of Science and Technology
Pollution Research | Year: 2013

A wetland is a complex assemblage of water, substrate, plants, invertebrates (insect larvae and worms) and micro-organisms (bacteria). These are inter-related and help in improving water quality by settling suspended particulate matter, adsorption and ion-exchange on the surfaces of plants, substrate and sediment, uptake and transformation of nutrients by micro-organisms and plants etc. A constructed wetland is a shallow basin filled with a substrate (soil or gravel) and planted with vegetation tolerant of saturated conditions. In the present study the performance of subsurface horizontal flow constructed wetland for treatment of sewage water was investigated. The substrate used is gravel and vegetation is a macrophyte (Typha latifolia) as they are easily available. Environmental related parameters i.e. pH, COD, BOD5, TSS, NH3-N, PO4 nitrate and Fecal coliform count were monitored in one complete macrophyte life cycle at different HRTs. At an optimum HRT of 2 days removal efficiencies of various parameters were in the range COD (95.3%), BOD5(100%), TSS (97.9%) and NH3-N (78.9%). The Fecal coliform showed 2-3 log reduction. The performances of the system indicate that constructed wetland treatment system is a viable option for sewage treatment. The system is cost effective and can be implemented successfully as a decentralized system in urban and rural areas using local resources. Copyright © Em International. Source

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