A round-robin test of the thermal expansion measurement for solid materials using thermal mechanical analysis (TMA) has been carried out. Fourteen participating laboratories of the test have measured linear expansion coefficients of single crystalline silicon and glass-like carbon, both of which have been established as the thermal expansion standard materials by the National Institute of Advanced Industrial Science and Technology (AIST), in the temperature range from room temperature to 1000 K. For both sample materials, the average data of linear expansion coefficients measured by all the participants were less by over 5 % than the corresponding reference data determined by AIST using the interferometric dilatometer. The analysis of all experimental results reveals that the measurement uncertainty of the results was mainly due to the reference samples used in the calibrations of TMA. To improve the accuracy of the measurement, it is very important to use reference samples having the same dimensions as the sample and similar characteristics for thermal expansion of the sample.

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An assemble of thermally stablized heat-sink block has been designed and constructed for a twin conduction type of microcalorimeter. Main heat-sink block is fixed on the bottom of the sealed inner container with the unipod, which is suspended from the upper wall of thermostated outer container with four bolts. Such construction is expected to work as a thermal filter of second order type against thermal fluctuation from the outside like electrical low-pass filter circuit. The performance test indicates that the thermal drift and noise in output baseline are less than 0.30 μW/24h and 0.039 μW/24h in energy equivalent value, respectively.

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Thermal effusivity relates to a material's ability to transfer heat. Applications of thermal effusivity sensor to evaluate the manufacturing and quality of pharmaceuticals are reviewed. The sensors use the thermal effusivity of samples to distinguish between water and powders with sensitivity down to 0.25 % moisture. Thermal effusivity can improve drying process control by providing real-time feedback about sample moisture content. The blending process and the optimal blending time for an experimental product were studied using a blender equipped with thermal effusivity sensors. The data obtained with thermal effusivity sensors was closely related to the current methodology using collected samples. Thermal effusivity measurements are an efficient tool to monitor real time blending behavior of pharmaceutical blends. In addition, optimal blending time can be determined using these sensors.

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Although use of glassy state for pharmaceutical formulations is not a new idea, it is recognized again as a promising formulation technology to enhance dissolution rate due to increase in poorly soluble candidates. However, because of its low physical/chemical stability and difficulty in industrial manufacturing, number of commercialized formulations has still been limited. In this review, molecular mobility of glassy pharmaceuticals is introduced with great emphasis on its effect on the physical/chemical stability.

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The surface tension measurements revealed that an appropriate coincidence in the difference in the hydrocarbon chain lengths between two surfactants with the hydrated hydrophilic group diameter caused the synergetic adsorption and micelle formation in the aqueous solutions of the mixture of hexadecyltrimethylamonium bromide (HTAB) - dodecyltrimethylammonium bromide (DTAB). This is explained by the theory of the staggered structure formation driven by the strong dispersion interaction between the alkyl chains of different surfactants. Furthermore, it was found that the synergism was considerably strengthened in the mixed system without common ions; hexadecyltrimethylammonium chloride (HTAC) - dodecyltrimethyammonium bromide (DTAB) system by the preferential adsorption of bromide ions over chloride ions onto the adsorbed film and micelle. A useful analytical procedure was developed to evaluate the composition of individual ions in the adsorbed film and micelle and applied to the HTAC-DTAB system.

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The amorphous-forming ability of some alloy systems has been evaluated in term of the critical cooling rate for amorphization. In this evaluation, the time-temperature-transformation (TTT) curves, which are a measure of the time necessary for the formation of detectable amounts of a crystalline phase from a supercooled liquid as a function of temperature, were calculated by introducing thermodynamic quantities obtained from the phase diagram calculations into the kinetic formulations. The evaluated amorphous-forming compositional range agreed well with the experimental results. In addition, the calculations showed that, at a given alloy composition, the phase other than the primary crystalline phase controls amorphization. Based on our thermodynamic calculations, this finding was closely related to the smaller entropy of fusion for the phase that controls amorphization versus that of the primary crystalline phase.

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