A modified integral counting method (MICM) with various quenched samples (MICM-VQ) has been investigated for its applicability for different scintillators using β emitters, ¹⁴C and ³⁵S. To assess the influence of scintillators, three sets of ¹⁴C quenched standards and two ³⁵S cocktail series were prepared. Two sets of ¹⁴C quenched standards were used for the toluene-compatible scintillator, the other for the Ultima Gold^TM scintillator. Sulfur-35 cocktail series were prepared with either Ecoscint^TM XR or Ultima Gold^TM AB. The radioactivity of these samples was determined using the MICM-VQ, with the results conforming to assayed values. Hence the MICM-VQ can assay the radioactivity of sample cocktails with various scintillators and requires no standard sample.

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 The seabed soil was collected at the Soya Strait of Hokkaido in September 2015, and ¹³⁴Cs derived from Fukushima Daiichi Nuclear Power Plant accident was detected at the seabed soil. It was suggested that this ¹³⁴Cs migrated from the Japan Sea to the Okhotsk Sea by the Tsushima Warm Current and the Soya Warm Current.

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 Radiophotoluminescence (RPL) photography has been proposed for the measurement of the spatial dose distribution of high radiation fields. A pulsed UV-LED illuminator was prepared as an excitation light source for the RPL photography. The fluorescence image of RPL material was observed by a gated intensified CCD camera. In a preliminary experiment, several tens of spherical RPL detectors were placed near an intense ⁶⁰Co source. The pulsed UV-LED illuminator and the gated intensified camera were pulse-operated to obtain the RPL photograph of the ball-shaped RPL detectors. The spatial dose distribution was calculated from the brightness of obtained RPL images.

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