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The conventional solid-state reaction route has been utilized to synthesize Hf0.5Zr0.5O2 ceramics. The surface morphology and structural properties are studied using scanning electron microscopy and X-ray diffraction patterns, respectively. The X-ray diffraction patterns show sharp and intense peaks explaining better crystallinity of compositional ceramic. The peak splitting around 31.7° confirms the tetragonal phase. The electrical measurements have been carried out on metal-ferroelectric-metal (MFM) capacitors. The calculated dielectric constant is around 26 at 1 MHz. The hopping of electrons over the trap centers leads to the ac conduction at a low field. Jonscher's power model justified the ac conductivity curve, and attained data are fitted accordingly. The polarization and coercive field decrease initially with the rise of measurement frequency and later increased with frequency. The ferroelectric hysteresis loop generally observed in the thin films of Hf0.5Zr0.5O2 has not seen the polarization-electric field curve of bulk Hf0.5Zr0.5O2. [ABSTRACT FROM AUTHOR]

The paper presents a comparative analysis on the laminar convective heat transfer characteristics of a 2-D flow over three different grooved profiles. The profiles selected for this study are trapezoidal, triangular and sinusoidal. The numerical simulation is performed using ANSYS-FLUENT SOLVER to elucidate the effect of changing fluidic properties over these channels in the Reynolds number range of 400-1400. The analysis is performed using two different fluids namely water and SYLTHERM 800 to present the changing thermal and fluidic behavior among the channels having fixed length and ribs. The influences of these profiles on pressure drop, streamline contours, temperature variations and entropy variations are discussed in details over these fluids, more over the results are presented in a comparative manner. The Governing equations are discretized using Finite Volume Method (FVM) and SIMPLE Algorithm along with Second Order Upwind Difference Scheme. When SYLTHERM 800 is passed through these channels in the given Reynolds number range it is observed that the trapezoidal channel has minimum decrement in entropy followed by sinusoidal and triangular channels for this flow conditions. Also, when we compared the results obtained using SYLTHERM 800 with traditional fluid i.e., water, then it is observed that there is more pressure drop, heat dissipation and entropy generation in case of SYLTHERM 800. The outcomes obtained in this work will further contemplate researchers to design various devices and systems with better thermal efficiency for various engineering and household applications. [ABSTRACT FROM AUTHOR]

The present study deals with the radon estimation in 40 water samples collected from different natural resources and radium content in the soils of Mandi-Dharamshala Region. Radon concentration is determined by using RAD-7 detector and radium contents of the soil in vicinity of water resources is as well measured by using LR-115 type -- II detector, which is further correlated with radon concentration in water samples. The potential health risks related with 222Rn have also been estimated. The results show that the radon concentrations within the range of 1.51 to 22.7Bq/l with an average value of 5.93 Bq/l for all type of water samples taken from study area. The radon concentration in water samples is found lower than 100Bq/l, the exposure limit of radon in water recommended by the World Health Organization. The calculated average effective dose of radon received by the people of study area is 0.022 mSv/y with maximum of 0.083 mSv/y and minimum 0.0056 mSv/y. The total effective dose in all sites of the studied area is found to be within the safe limit (0.1 mSv/year) recommended by World Health Organization. The average value of radium content in the soil of study area is 6.326 Bq/kg. [ABSTRACT FROM AUTHOR]