Enthalpy and Heat-Capacity Standard Reference Material: Synthetic Sapphire (Alpha-Al2O3) From 10 to 2250 K

Abstract

Heretofore unpublished enthalpy data which were used in the derivation of smooth enthalpy and heat-.capacity data for NBS SRM 720 (a-A1, 2 0, heat capacity and enthalpy standard) are presented along with some details of the high-temperature experiments. Recent NBS low-temperature measurements on SRM 720 are smoothed by a least-squares spline technique and a revised table of certified values for enthalpy and heat capacity of a-Al,() from 10 K to near the meltng point (2250 K) is presented.

Crystal structures and thermodynamic properties on phase change materials n-CnH2n+1NH3·H2PO4(s) (n=8, 9 and 10)

“…The reliability of the calorimeter has been confirmed by heat capacity measurements of the reference standard material (a-Al 2 O 3 ) over the temperature range 78 r(T/K)r400. Deviations of the experimental result from those of smoothed curve lie within 70.20%, while the uncertainty is 70.30%, as compared with the values given by the former National Bureau of Standards [16] over the whole temperature range.…”

Heat Capacity and Thermodynamic Properties of Myclobutanil

“…The sample mass used for the measurements was 1.5412 g, which was equivalent to 0.005337 mol based on its molar mass, M (Al 2 O 3 )＝101.96 g•mol -1 . Deviations of the experimental results from those of the smoothed curve lay within ±0.2%, while the inaccuracy was within ±0.5%, as compared with those of the former National Bureau of Standard 7,8 over the whole experimental temperature range.…”

Characterization and thermodynamic study of ultra-fine particle of Ni–B amorphous alloy

“…1 mK. Heat-capacity measurements of -Al 2 O 3 over the temperature range of 60±350 K indicate that deviation of the experimental results from the smoothed curve lie within AE0.2%, while the inaccuracy is within AE0.5%, as compared with those of the National Bureau of Standards [5]. The sample mass used for the calorimetric study is 2.943 g (0.094 mol based on the molar mass of 31.148 g mol À1 ).…”