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The accuracy of the prompt γ-ray analysis is known to degrade for the samples containing neutron-scattering materials, such as hydrogen, depending on its content. Recently, we discovered that the density of the scattering materials also affects the accuracy. In this paper, we developed a correction method for the effect of the sample densities. The developed correction method is straightforward and applicable to samples with unknown densities. The simulation and experiments verified the performance of the correction method. The results confirmed that the correction method could reduce the uncertainty due to sample density from 47% to approximately 1%. [ABSTRACT FROM AUTHOR]

We determined the free + adsorbed water and the bound water in aggregates and cement pastes using conventional gravimetric analysis and prompt γ-ray analysis, respectively, to evaluate the total water content in concretes. The contents of free + adsorbed water and bound water in some geochemical references were also determined to confirm the accuracy in the present work. The content of each water in aggregates collected from different quarries and cement pastes with different water-to-cement ratios were analyzed. The total water content in young concrete was evaluated on the basis of the analytical values. [ABSTRACT FROM AUTHOR]

211At is artificially produced for medical purposes. To prevent severe loss of short-lived 211At, a rapid method analyzing both the radioactivity and all chemical forms was required for related fundamental researches. We propose a new method by means of an α-scintillation-camera system comprising of thin-layer chromatography and a high-sensitive CCD camera. The performance of the system was experimentally verified: low-radioactivity 211At of 56–672 Bq was measured in a short-time of 1000 s and all chemical forms of 211At were evaluated. The results reveal that the method enables us to analyze two features of 211At with significantly short-time. [ABSTRACT FROM AUTHOR]