Specific heat capacity of Apiezon N high vacuum grease and of Duran borosilicate glass

Accurate heat capacity measurements on powdered samples using a Quantum Design physical property measurement system

“…Accordingly, these increased errors are likely due to the irreproducibility in the heat capacity of Apiezon N grease at these higher temperatures. Schnelle et al [29] have reported that there is a heat capacity anomaly near T = 220 K and a broad peak near T = 290 K in the heat capacity of Apiezon N grease, which Kreitman [30] attribute to a glass transition and fusion/crystallization, respectively. The heat capacity of these two anomalies has been shown to be quite irreproducible, and consequently the subtraction of the Apiezon N contribution from the total heat capacity causes an increased uncertainty in the final sample heat capacity in this temperature region.…”

Calorimetric Determination of Heat Capacity, Entropy and Enthalpy of Mixed Oxides in the System CaO–SrO–Bi2O3–Nb2O5–Ta2O5

“…The sample heat capacity was then obtained as a difference between the two data sets. This procedure was applied, because the heat capacity of Apiezon is not negligible in comparison with the sample heat capacity (~8 % at room temperature) and exhibits a peak-shaped transition below room temperature [37]. The manufacturer claims the precision of this measurement better then 2 % [38]; the control measurement of the copper sample (99.999 % purity) confirmed this precision in the temperature range 50-250 K. However, the precision of the measurement strongly depends on the thermal coupling between the sample and the calorimeter platform.…”

Heat capacity, enthalpy and entropy of strontium niobates Sr2Nb10O27 and Sr5Nb4O15

“…The sample heat capacity was then obtained as a difference between the two data sets. This procedure was applied, because the heat capacity of Apiezon is not negligible in comparison with the heat capacity of the sample (∼8% at room temperature) and exhibits a sol-gel transition below room temperature [8]. The manufacturer claims the precision of this measurement better then 2% [9]; the control measurement of the copper sample (99.999% purity) confirmed this precision in the temperature range 50-250 K. However, the precision of the measurement strongly depends on the thermal coupling between the sample and the calorimeter platform.…”