Sintering of barium titanate by microwave heating with barium borate as a liquid-phase forming material was examined as a
means of saving energy. A liquid phase was generated faster and over a wider temperature range by intermittent heating at
constant power than by constant heating with variable power. When sufficient amount of the liquid-phase forming material were
present, the samples were densified at temperatures below those at which the liquid-phase is normally formed. A sample containing
10 mol% of the liquid-phase forming material was densified efficiently. When too much liquid-phase forming material was present,
densification of the sample was obstructed.
Carrier- and salt-free42K milked from an42Ar–42K generator was utilized for isotope dilution analysis of potassium in ultra-pure water. Potassium in the sample marked with the42K was shown to be concentrated easily 60 times by crown-ether extraction and acid back-extraction to be determined by atomic absorption spectrophotometry. The same extractions proved to be effective for removing the reagent blank. Cerenkov radiation counting was often suitable for42K measurement. The42K was used also for studying the interaction of ultra-low concentrations of potassium with vessel walls.