Enhanced thermal properties of Li2CO3–Na2CO3–K2CO3 nanofluids with nanoalumina for heat transfer in high-temperature CSP systems

Nanofluids of Li₂CO₃–Na₂CO₃–K₂CO₃ improved by three nano-Al₂O₃ samples are firstly prepared by means of two-step aqueous method to enhance thermal properties for high-temperature heat transfer, when used as heat transfer fluids and thermal energy systems for concentrating solar power systems. Specific heat of ternary carbonates containing Al₂O₃ of 0.2, 0.4, 0.8, 1.0, 1.4 and 2.0 mass% is measured, and nanofluids with 1.0 mass% of 20-nm Al₂O₃, 1.0 mass% of 50-nm Al₂O₃ and 0.8 mass% of 80-nm Al₂O₃ are selected as superior candidates. The maximum enhancement of specific heat is 18.5% in solid and 33.0% in liquid, 17.9% in solid and 22.7% in liquid, 13.2% in solid and 17.5% in liquid for nanofluids containing 20-, 50- and 80-nm Al₂O₃. Thermal conductivity is, respectively, improved by 23.3, 28.5 and 30.9% under the addition of Al₂O₃. New chemical bonds and crystals are scarcely formed in composites through FT-IR and XRD determination. SEM images certify that nano-Al₂O₃ are homogeneously mixed into nanofluids and this structure may be a critical incentive for enhancing thermal properties. There are no significant changes with respect to the heat flow, melting/freezing point and latent heat after the 30 circles of determination. Briefly, it can be speculated that these nanofluids will exhibit tremendous potential in the coming applications of heat transfer and thermal storage for concentrating solar power systems.

     

Overtaking collisions of oblique isothermal ion-acoustic multisolitons in ultra-relativistic degenerate dense magnetoplasmas

Overtaking collisions of oblique isothermal ion-acoustic multisolitons are studied in an ultra-relativistic degenerate dense magnetoplasma, containing non-degenerate inertial warm ions and ultra-relativistic degenerate inertialess electrons and positrons. A non-linear Korteweg-de Vries (KdV) equation describing oblique isothermal ion-acoustic solitons (OIIASs) in such a plasma model is derived. By applying Hirota's bilinear method (HBM), the overtaking collisions of oblique isothermal ion-acoustic multisoliton solutions are investigated. An in-depth discussion shows that the amplitude, the width, and the phase shift of isothermal ion-acoustic multisolitons increase as the obliqueness and the chemical potential of electrons increase. The deviation of the trajectories decreases with increasing concentration of fermions and the ion cyclotron frequency. The present finding of this study is applicable in compact objects, such as white dwarfs and neutron stars, having degenerate ultra-relativistic dense electrons and positrons.     

The removal of methylene blue as a remedy of dye-based marine pollution: a photocatalytic perspective

Research on Chemical Intermediates - The effluents containing the discarded water from the textile industry are graded as one of the foremost pollutants in all industrial sectors. The wide...