An advanced sterilization system using exited oxygen species, such as exited singlet oxygen molecules (1O2) and exited singlet atomic oxygen (O(1D)), by ultraviolet irradiations was investigated. Viability of Geobacillus stearothermophilus spore was estimated with a biological indicator (BI) in the active oxygen sterilization (AOS) system. Survival curves of Geobacillus stearothermophilus spore showed exponential reduction. Decimal reduction time (D-value) was found to be 6.8 min., when the active oxygen was irradiated by four or five UV lamps. It was found that Geobacillus stearothermophilus spore was not sterilized by the UV irradiation, but the active oxygen irradiation. We believe that this sterilization system can be applied for medical device sterilization as a new sterilizer.
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.
Performance of a solid oxide fuel cell (SOFC) using gadolinia doped ceria (GDC) electrolyte film was studied on the power generation property at intermediate operating temperatures between 400 and 600℃. The crystal structure of GDC film of 3 µm thickness, which was grown by the helicon wave excited plasma sputtering, indicated a columnar structure with many grain boundaries. The open circuit voltage (OCV) of single cell showed the maximum value at operating temperature of 500℃, and the observed OCV of the series-connected two cells was 1075 mV. However, the current of series-connected cells was reduced to very small values because of the overvoltage due to mainly the ohmic resistance of GDC electrolyte and the reaction resistance of electrodes.
New water-cooled movable masks made of forged 0.2% beryllium copper alloy have been developed and applied to the front end of the BL-13A undulator beamline at the Photon Factory in Tsukuba, Japan. The masks have a simple structure, are low in cost, and have an extremely low outgassing rate.