抄録
The gas analysis system with EI-QMS (Electron Ionization-Quadrupole Mass Spectrometer) developed by Japan Atomic Energy Agency (JAEA) is commercially available from a private company through a technology transfer. The system has already been used to a medical field such as breath analysis, a quality control of automobile casting parts made of recycled aluminum, and a measurement of food aromatic elements emitting from vegetable and sake. A pulse gas sampling and a continuous evacuation were integrated to the system that aimed at obtaining high sensitive and stable mass spectrum and accomplishing fast measurement prepared for 100% inspection of industrial parts and various foods. As a result, the system achieved a background pressure of 10−7 Pa and a background ion current of 10−13 A in the normal condition. An intensity of the mass spectrum decreased linearly with decreasing the pressure by the continuous evacuation, therefore, the intensity of the mass spectrum was corrected by the pump down curve, which is a new mathematical approach equivalent to a constant pressure curve. It was confirmed that the system had the sensing performance of 100 ppb.
