We use cryogenic helium buffer-gas cooling to form large densities of lithium atoms in a high-density helium gas, from which LiHe molecules form by three-body recombination. These weakly bound van der Waals molecules are detected spectroscopically, and their binding energy is measured from their equilibrium thermodynamic properties.

In this paper, the sol-gel technique has been employed to prepare the pure and TM (Mn, Cr) doped BiFeO₃ nanoparticles. The synthesized nanoparticles were characterized using X-ray diffraction, UV-vis spectroscopy, photoluminescence, and dielectric measurements. Crystal structural analysis infers that pure and TM-doped BiFeO₃ nanoparticles displayed a rhombohedral distorted perovskite structure with R3c space group, along with a minor phase of Bi₂Fe₄O₉. Lattice parameters have been found to decrease with TM doping. The particle size, measured with the help of the XRD spectra, was found to decrease from 54.4 nm to 38.7 nm with TM doping. The bandgap, determined using the UV-vis spectra, was observed to be 1.92, 1.66, and 1.54 eV for undoped, 5% Mn, and 5% Cr-doped BiFeO₃ nanoparticles, respectively. The dielectric constant shows a normal dispersion behavior at room temperature and its value increases with TM doping. The ac conductivity also increases with TM doping in BiFeO₃ nanoparticles.

In this work, the effect of KBrO3 on the photodegradation mechanism of Nb-TiO₂ nanocomposites was analyzed. The photocatalytic activities of Nb-TiO₂ were evaluated by using a high concentration of phenol red (PR). Nb-TiO₂ nanocomposites were fabricated by a simple sol–gel route with new experimental conditions. HRTEM and EDX were used to study the structural properties of the Nb-TiO₂ nanocomposites. KBrO₃ decreased the degradation time of 20 mg·L⁻¹ of phenol red to 110 min, shorter than that in our previous work without KBrO₃. In addition, the results showed that the addition of KBrO₃ led to a significant degradation process, which reached an efficiency of 95%. The fast decomposition of the PR pollutants was due to the charge transfer between the KBrO₃ and Nb-TiO₂ nanocomposites in the wastewater treatment.

Non-Newtonian fluids, particularly those with high viscosity and complex flow behavior, present unique challenges in manufacturing processes. The modeling of their flow dynamics is crucial to achieve the desired outcomes in industrial applications. This study aims to theoretically model and analyze the flow dynamics of the Eyring–Powell fluid under varying temperature conditions using lubrication approximation theory and perturbation method. To simplify the mathematical formulation of fluid flow motion, lubrication approximation theory is applied. Using a perturbation method, the dimensionless governing equations are solved to derive expressions for velocity, pressure gradient, and pressure distributions. Numerical integration is then used to calculate critical engineering parameters, such as power input and roll-separating force, offering practical insights for optimizing the manufacturing process. Additionally, using the response surface method, Nusselt number ( Nu ) , sheet thickness H H 0 , and shear stress ( S x y ) , simulations were carried out to investigate the influence of variable viscoelastic parameters on the response functions ( Nu , H H 0 , and S x y ). The virtuousness of appropriate of the empirical model is obvious based on the coefficient of determination ( R 2 ) obtained from the analysis of variance. The findings reveal that the Weissenberg number, viscosity parameter, and Brinckmann number significantly influence velocity distribution, pressure profiles, power input, and roll-separating force, which are critical factors in the calendering process. Furthermore, the heat transfer rate shows an increase of approximately 5% with the rising values of the involved parameters, highlighting their significant influence on thermal performance. The coefficients of determination ( R 2 ) rise by about 99% for all response parameters, indicating the empirical model’s goodness of fit. These results provide valuable insights for engineers and researchers working on the calendering process of non-Newtonian fluids with complex rheological behavior, enabling better optimization of manufacturing processes and improved industrial outcomes.