While the major target of this contribution was the stabilization of the theoretically predicted CsCl form of the sodium chloride which could exhibit a singular and peculiar metallic behavior, this study took advantage of the nano-scaled aspect of the synthesized NaCl to report for the first time in the literature, the size dependence of various thermodynamic parameters of nano-sized NaCl crystals. More accurately, size effect on vaporization temperature of NaCl nano-crystals has been conducted on NaCl nanoparticles exhibiting a net shape anisotropy. The investigated nano-scaled NaCl particles were micrometric in the basal plane while nanometric in the transversal direction. An obvious size variation of the vaporization temperature is observed experimentally in agreement with the theoretical predictions. Specifically, the vaporization temperature T V decreases from almost 1680 (bulk) to 1290 K (nano-sized): a relative decrease of nearly 23.5%. The T V ≈ T(χ) size dependence where χ is the relative molar concentration of the initial NaCl precursor was found to follow the form T V (° C ) ≈ 750.7χ2 - 340.1χ + 1002.

This contribution reports for the first time the possibility of using radiolysis to engineer stable efficient nanofluids which exhibit an enhanced thermal conductivity. The validation was confirmed on Ag-H2O and Ag-C2H6O2 nanofluids fabricated via g-radiolysis within the mild dose range of 0.95 × 103–2.45 × 103 Gray. The enhanced thermal conductivity of Ag-H2O and Ag-C2H6O2 nanofluids, was found to be g-radiations dose dependent. In the latter case of Ag-C2H6O2 nanofluid, the relative enhancement in the temperature range of 25–50 °C was found to be 8.89%, 11.54%, 18.69%, 23.57% and 18.45% for D1 = 0.95 × 103 Gray, D2 = 1.2 × 103 Gray, D3 = 1.54 × 103 Gray, D4 = 1.80 × 103 Gray and D5 = 2.45 × 103 Gray respectively. Yet not optimized, an enhancement of the effective thermal conductivity as much as 23.57% relatively to pure C2H6O2 was observed in stable Ag-C2H6O2 nanofluids. Equivalent results were obtained with Ag-H2O.

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