The laser-pulse method is a well-established nonsteady-state measurement technique for measuring the thermal diffusivity, a, of solid homogeneous isotropic opaque materials. BNM-LNE has developed its own bench based on the principle of this method in which the thermal diffusivity is identified according to the "partial time moments method." Uncertainties of thermal diffusivity by means of this method have been calculated according to the ISO/BIPM "Guide to the Expression of Uncertainty in Measurement." Results are presented for several cases (Armco iron, Pyroceram 9606) in the temperature range from 20 to 800 • C. The relative expanded (k = 2) uncertainty of the thermal diffusivity determination is estimated to be from ±3 to ±5%, depending on the material and the temperature.

grown by atomic layer deposition could be proposed as a nonactive layer for back end processes in view of the integration of scaled phase change memory devices. In this paper we report on thermal characterization from 50 to 600°C of amorphous Al 2 O 3 thin films grown on thermally oxidized silicon substrate at a temperature of 100°C and capped with a 30 nm thick Pt layer. The effects of low temperature deposition and of a post-deposition rapid thermal annealing process (RTP) on the thermal properties of the films are investigated using a modulated photo-thermal radiometry technique coupled with post-annealing morphological characterizations. Degassing process occurring at high temperature greatly affects the film surface quality, though measurements of the films after RTP show that the thermal conductivity of amorphous Al 2 O 3 increases as a function of temperature from 1.8 W K À1 m À1 at 50°C to 3.3 W K À1 m À1 at 600°C. At the same time, the value of the thermal boundary resistance at the Pt-Al 2 O 3 interface decreases from 1.02 Â 10 À7 K m 2 W À1 at 50°C to 4.8 Â 10 À8 K m 2 W À1 at 600°C.

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A new reference calorimeter has been developed under a European research project and set-up by Physikalisch-Technische Bundesanstalt (PTB) in Germany. The objective of the project is to measure the superior calorific value (SCV) of methane and other pure gases with a measurement uncertainty of less than 0.05 %. This paper presents the measurement results obtained for methane. Nine repeatability measurements were made. The molar SCV obtained when the measurements were averaged is 890.578 kJ·mol −1 . This value agrees very accurately with the value of 890.63 kJ·mol −1 specified by ISO 6976 [Natural Gas-Calculation of Calorific Values, Density, Relative Density and Wobbe Index from Composition. International Standard ISO 6976, corrected and reprinted 1996-02-01]. Twice the standard deviation determined for the measurements is 0.023 % and is thus clearly lower than in previous 123 666 Int J Thermophys (2010) 31:665-679experiments. Two independent uncertainty analyses confirm that the envisaged total uncertainty of 0.05 % is achieved (95 % confidence level).

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A new in situ high temperature electrical calibration system was developed at Laboratoire National de Metrologie et d'Essais, Laboratoire Commun de Metrologie and integrated into a heat flux Calvet calorimeter in order to perform accurate and reliable measurements of enthalpy of fusion that are directly traceable to the International System of Units (SI). This system has been designed to enable the calibration of the calorimeter by electrical substitution (Joule effect) as well as the measurement of enthalpy of fusion in perfectly identical experimental conditions. The metrological features (repeatability, linearity, etc.) of the calorimeter have been evaluated with this system by investigating the influence of some parameters (level of energy, dissipation time, and temperature) on the determination of the sensitivity factor of its thermopiles. Two different procedures, for the calibration and the enthalpy measurements with this new electrical calibration system, have been implemented and tested by measuring the enthalpy of fusion of high purity 6N tin. The results obtained are in very good agreement with those measured by other National Metrology Institutes on the same material.