@article{oai:niigata-u.repo.nii.ac.jp:00028138,
 author = {橋本, 哲夫 and 野中, 雅史 and 酒井, 裕二 and 重富, 潤一 and 青木, 滋 and 佐藤, 修},
 journal = {新潟大学積雪地域災害研究センター研究年報, 新潟大学積雪地域災害研究センター研究年報},
 month = {Dec},
 note = {The electrolytic enrichment method has been widely used in many laboratories in order to measure accurately the naturally occurring low-level tritium concentration. However, it is not only impossible to determine the practical enrichment factor of tritium for each cell, but also separation factors of tritium are greatly influenced by experimental factors, such as the surface condition and electrolytical history of the electrode, applied current density, temperature, and so on. In this report, firstly a simple and conventional determination of deuterium was established by using a NMR (Nuclear Magnetic Resonance) apparatus, combined with an internal standard of deuterated acetone. It was verified that this method is applicable to the determination of deuterium concentration ranging from about 150 ppm (corresponding to average deuterium concentration in natural water) to 1300 ppm; the measurement of accuracy being about ± 4%. Subsequently, since deuterium together with tritium is also enriched during the electrolytic procedure, the enrichment factor of deuterium for each cell was taken into account as an indicator in place of tritium enrichment. After the electrolytic enrichment, the deuterium concentration in the residual water samples could be directly measured by the NMR method, while tritium concentrations were also determined by a liquid scintillation counting method. Finally, the relationship between α and β, corresponding to the separation factors of deuterium and tritium, respectively, was evaluated for Ni-Ni and Ni-Fe electrodes as illustrated in Fig. 7. It was concluded that the Ni-Fe electrode gives a preferably higher enrichment factor for tritium than Ni-Ni electrode, although there remain the problems related to dissolution of the anode material during the electrolysis.},
 pages = {135--143},
 title = {天然水中の極低レベルトリチウム測定のための基礎的研究 :卜リチウムの電解濃縮における^2D-NMRの利用},
 volume = {9},
 year = {1987}
}