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This comprehensive study examines the concentration of natural radionuclides in bricks from the Terai region of the Koshi province, aiming to assess the radioactivity levels and associated radiological hazards, ultimately quantifying the dose limit. The average concentrations of 226 Ra, 232 Th, and 40 K were 27.1 ± 5.7, 42.6 ± 9.8, and 601.5 ± 93.8 Bq/kg, with their respective contributions to total activity being 20.18 %, 45.35 %, 34.48 %,. Despite this, their concentration distribution followed the pattern 40 K >  232 Th >  226 Ra. The elevated presence of 40 K in the bricks is attributed to the use of phosphate fertilizers in the soil to enhance crop productivity. Notably, the calculated values of radiological hazard parameters, including radium equivalent activity, absorbed gamma dose, and effective dose, are well below the recommended safety thresholds. Consequently, this study suggests that bricks, when used in substantial quantities, pose no significant radiological risks and are considered safe for use as a building material. The extension of such investigations nationwide is recommended to assess the overall radioactivity levels and establish dose limits., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Arun Kumar Shrestha reports University Grants Commission Nepal provided a Ph.D. fellowship and research support grant including a travel reimbursement. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Temperature-dependent interaction parameters of Redlich-Kister (R-K) polynomials for Li-Mg alloy in liquid phase have been optimized using experimental data in the framework of linear and exponential models. These parameters have then been used to compute the thermodynamic properties (excess Gibbs free energy of mixing, enthalpy of mixing and activity) and structural property (concentration fluctuations in the long-wavelength limit) of the alloy at temperatures 1000 K, 1300 K, 1600 K, 1900 K, and 2200 K. The negative values of excess Gibbs free energy of mixing computed using linear T-dependent parameters increases with the rise in the temperature of the system beyond 1000 K while the same physical quantity computed using the exponential T-dependent interaction parameters decreases with the rise in temperatures and does not show any unusual trends up to 2200 K. Similar behavior has been found in the case of other thermodynamic and structural functions. The unusual behavior that appears in the thermodynamic and structural functions computed using linear T-dependent parameters can be eliminated if these functions are computed using exponential T-dependent parameters., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

The surface tension and viscosity of Cu-Fe-Si ternary alloys were computed at different temperatures using thermodynamic approaches. The thermodynamic data of the alloy were optimized in the framework of the Redlich-Kister (R-K) polynomials and exponential temperature dependent coefficients of the R-K polynomial were obtained. These coefficients were used to compute the excess Gibbs free energy of mixing of the alloy and the partial excess free energy of the components. The partial excess free energy so obtained was used to compute the surface tension of the ternary Cu-Fe-Si alloy system and its binary sub-systems. The enthalpy of mixing was also optimized and it was used to compute the viscosity of the sub-binary and ternary alloys., (© 2020 The Author(s).)