A semiconductor device includes a semiconductor layer with an impurity of a first conductivity type diffused therein, and a local insulating layer, source layer, and a drain layer formed therein. A total amount of refrigerant in a refrigerant circuit 10 is calculated based on the calculated inner volume of the refrigerant extension piping and the current set of operation data, and the calculated total refrigerant is compared with a reference amount of refrigerant to determine a presence or absence of refrigerant leakage. There is also provided further mixtures containing additional components, as well as methods of using the mixtures in various applications, such as for the electroreduction of the mixtures to produce aluminum metal. The irradiation apparatus exposes a diseased part to the generated ion beam. Accordingly, light passed through slits for controlling the divergence angle of incident light or the etendue of an optical system has a Gaussian distribution in a color separation direction or a color scrolling direction. The interface is extensible to make it easy to add new applications.