Fig 5. Selected thermal conductivity measurements for DP6+IONP, where all other CPAs and nanofluids combinations were found within the yellow range; H₁ refers to the initial cooling rate between 12ºC and -100ºC, where measurements were taken during passive warming to -100°C and at 3°C/min thereafter.

Pure DP6 was measured previously and is displayed here for reference [13, 18].