A Prototype Model to Improve Bandwidth of E Shaped Microstrip Patch Antenna

In this communication we have demonstrate a prototype model to improvise bandwidth of E shaped microstrip patch antenna. Microstrip patch antenna is widely used in wireless communication system. Patch antenna has number of advantage over other antenna. It is low volume, thin profile configuration, light weight and easy to integrate with accompanying electronics which can made conformal but, Microstrip patch antenna has several limitations like narrow bandwidth and associated tolerance problem, lower gain. Patch antenna can be designed on simulation software like HFSS. This paper present Design and simulation of E shaped microstrip patch antenna and analyzed result Bandwidth, Gain, Return loss etc has been presented.Derived results show that E shaped Patch antenna is better for the improvement of Bandwidth of the antenna

Charge transport mechanisms in monovalent doped mixed valent manganites

Abstract In this communication, we report the results of the studies on structural and transport properties of monovalent Na + doped La 1-x Na x MnO 3 (LNMO; x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) manganites synthesized by conventional ceramic method. X-ray diffraction (XRD) and Rietveld refinements reveal the single phasic nature of LNMO manganites without any detectable impurity within the measurement range. Temperature dependent resistivity, under different applied magnetic fields, has been performed on LNMO samples. Samples understudy exhibit metal to insulator (semiconductor) transition at temperature T P which is strongly influenced by the substitution of Na + at La 3+ site. -T plots also exhibit resistivity upturn behavior at low temperature well below 40K under all the applied fields. Variation in T P and resistivity has been discussed in the context of the competition between the transport favoring tolerance factor and zener double exchange (ZDE) mechanism and transport degrading Jahn-Teller (JT) and size variance effects. In order to understand the mechanisms responsible for the charge transport in metallic and semiconducting regions and to explore the possible electronic processes responsible for the observed low temperature resistivity minima in all the presently studied LNMO manganites, various models have been employed. It has been found that VRH mechanism gets successfully fitted to the resistivity data in the semiconducting region while ZDE polynomial law is responsible for the charge conduction in metallic region for all the presently studied LNMO samples. A strong dependence of activation energy on the Na + -content as well as applied magnetic field has been discussed in the context of variation and interrelations between the structural parameters. Charge conduction in metallic region has been discussed in the light of electron-phonon interactions which is influenced by the Na + -content and applied magnetic field. Electrostatic blockade model has been employed to understand the low temperature resistivity minima behavior. Blocking energy for the charge carriers shows a dependence on the magnetic energy provided to the charge carriers. Present study can be useful to understand and to control the charge conduction in the manganites and hence to design the manganite based thin film devices for various spintronic applications

Studies on Plasmonic Properties of Environmental Sensitive Copper Nano Particles Prepared Cost Effective Method

Due to scientific and industrial interest, copper nanoparticles have attracted a lot of interest in the current decade, special due to its applications in anti-biotic, anti-microbial and anti-fungal agent, catalysis, conductive inks, coatings, coolant and textiles. The present study focused, on the cost effective synthesis technique and environmental effects on copper nanoparticlesdue to its high surface sensitivity. The structural composition, particle size and optical properties of copper nanoparticleswere determined by X-raysand UV-Visible spectroscopy, reveals that the particles have size in order to 9 nm. A plasmonic study through a UV-visible spectrum shows the peak shift from 411 to 316 nm, with color change in the coppernanoparticles indicate the surface sensitivity due to very large surface area.The synthesis method, reported in current work might be useful for industrial production of Cu nanoparticles