The experimental techniques of high-temperature heat flow calorimetry are explained in view of selection and mass optimisation of standards for caloric calibration, condition of samples, heating rates and liner materials. Calorimetric work is illustrated on enthalpy measurements of Li
4SiO
4, Li
2SiO
3, Li
2ZrO
3, LiAlO
2 and Li
2TiO
3 by isothermal drop calorimetry and by heat capacity calculations therefrom. The physics of second-order transitions is discussed taking Li
4SiO
4 as an example. An additional enthalpy uptake occurs in the critical temperature range under anisothermal conditions. The behaviour is reversible. The anisothermal calorimetry is further outlined by measurements of the enthalpy of solidification of Li
4SiO
4 and the enthalpy of transformation and melting of beryllium.
抄録全体を表示