Chemical substances and the chemical processes that handle them inherently have energy potential. Therefore, for safe and efficient operation and management, it is necessary to appropriately evaluate the hazards of these substances and processes, and to implement risk management appropriately to the purpose based on the results. Measuring the amount of heat generated during the reaction and its time change is meaningful for evaluating the hazards of these chemical substances and processes, and the use of calorimetry techniques is effective for obtaining this information. This paper presents examples of serious accidents that have occurred in chemical reaction systems in the past and their causes, and introduces hazard/risk evaluation methods for the safe operation of chemical substances and processes, as well as their effectiveness and application.

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Recent advances in magnet technology have enabled the generation of pulsed magnetic fields of 40–60 T with pulse durations on the order of one second and highly stable flat-top waveforms. Taking advantage of such long-pulse high magnetic fields, we have developed a high-speed and high-precision heat capacity measurement technique based on the quasi-adiabatic method. By optimizing the calorimeter design and the measurement system, a single heat capacity data point can be acquired within approximately 10 ms, allowing efficient data collection within a single field pulse. The combination of a highly stable flat-top magnetic field and a dedicated probe design results in a measurement resolution better than 1 nJ K−1 at 1 K, exceeding the performance of commercial heat capacity measurement systems. Further improvements in the measurement algorithm enable highly efficient experiments, making it possible to complete comprehensive measurements on a single sample within several days of magnet time. The technique presented here is expected to contribute significantly to condensed matter research as pulsed-magnet technologies continue to advance worldwide.

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CALPHAD is a powerful tool for both materials design and process optimization through the various thermodynamic calculations with the phase diagram databases written in a TDB (Thermodynamic DataBase) format. In the CALPHAD-type thermodynamic assessments, the thermodynamic quantities are critically evaluated and accumulated in the TDB files as Gibbs energy functions of phases. Although CALPHAD has been started with alloys and metallic systems, it is not limited to those materials and thus can be applied to wider scientific fields. Currently several software packages and multi-component phase diagram databases are available for variety of materials and applications such as hard/soft magnets, batteries, structural materials, nuclear materials, aqueous systems and so on. In the present review, overviewing the progress of phase diagram investigations and the beginning of CALPHAD, the future of phase diagrams and computational thermodynamics will be discussed.

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