We report structural, optical, temperature and frequency dependent dielectric, and energy storage properties of pulsed laser deposited (100) highly textured BaZr x Ti 1−x O 3 (x=0.3, 0.4 and 0.5) relaxor ferroelectric thin films on La 0.7 Sr 0.3 MnO 3 /MgO substrates which make this compound as a potential lead-free capacitive energy storage material for scalable electronic devices. A high dielectric constant of ~1400-3500 and a low dielectric loss of <0.025 were achieved at 10 kHz for all three compositions at ambient conditions. Ultrahigh stored and recoverable electrostatic energy densities as high as 214 ± 1 and 156 ± 1 J/cm 3 , respectively, were demonstrated at a sustained high electric field of ~3 MV/cm with an efficiency of 72.8 ± 0.6 % in optimum 30% Zr substituted BaTiO 3 composition.Future use of electricity generated from any renewable energy source will benefit greatly from advanced approaches to scalable capacitive energy storage module with a favorable figure for the power-to-mass ratio (specific power) including its usage in personal electronics,

Present work was carried out to collect primary data from the field with the help of noise meter and thus spatial and diurnal variation of background and aircraft noise level was analyzed. Seventeen sampling sites were chosen nearby Tribhuwan International Airport (TIA) and air route of aircraft flyover. Noise measurements were carried out under normal atmospheric environmental condition at temperature ranges from 25 0 C-30 o C excluding rainy and windy days. Among the sampling sites, the Equivalent Continuous Noise Level (L Aeq ) of background noise measured maximum at Balkumari (73.2 dBA) and minimum at Datidol (49.2 dBA). Noise meter was allowed to record aircraft noise level when aircraft produced noise greater than background noise level and recorded until it reduced to background noise level. The maximum value of aircraft noise level, (L Aeq ) measured at Gothatar (101.5 dBA) which lies north east from the TIA and at the same height as the airport ground and minimum at Datidol (63.5 dBA).To analyse the spatial variation of aircraft noise of different sampling sites, contour map was plotted with the help of origin software. The L Aeq of more than 60 percent sampling sites fall under the severe noise exposure class (> 75 dBA) which causes substantial hearing loss. Implementation of noise control measurement and public awareness are recommended to control adverse effect of noise pollution.

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Highly oriented 0.90[PbZr0.53Ti0.47]0.10[La0.80Sc0.20]O3-δ (PLZTS) thin films deposited on La0.67Sr0.33MnO3 (LSMO) coated MgO (100) substrates were grown by pulsed laser deposition technique. Temperature dependent dielectric measurements on metal-ferroelectric-metal Pt/PLZTS/LSMO thin film capacitors were carried out at several frequencies which exhibit high dielectric constants (450–580) with the diffuse peak around 400 K, and the diffusivity parameter γ was obtained as 1.96 for 100 kHz data. The slim polarization-electric field hysteresis loop was observed with less remanent polarization (∼7–10 μC/cm2) indicating its relaxor behavior. Temperature dependent Raman spectra measured between 80 and 550 K show softening of the symmetric E(LO2) band that disappeared at 300 K, corroborating the tetragonal-cubic phase transition. From the analysis of the measured hysteresis loops, the recovered energy density Ure ∼ 19 J/cm3 with the efficiency η ∼ 66% was estimated, suggesting its possible application in energy density capacitors.