Yunoki Akira, Yamada Takahiro, Kawada Yasushi, Unno Yasuhiro, Sato Yasushi, Hino Yoshio
National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan.
Appl Radiat Isot. 2010 Jul-Aug;68(7-8):1340-3. doi: 10.1016/j.apradiso.2009.12.030. Epub 2009 Dec 21.
The National Metrology Institute of Japan (NMIJ) participated in the CCRI(II) Key-comparison of (85)Kr activity measurement. The absolute internal gas-counting method was used, with a set of proportional counters of different length. The original (85)Kr gas was diluted by a factor of 2x10(5) in order to achieve the suitable activity concentration for the proportional counters. A new dilution method was introduced, based on a large-volume balloon and gravimetric determination of the dilution volume with small uncertainties.
日本国家计量院（NMIJ）参与了85氪活度测量的CCRI（II）关键比对。采用了绝对内部气体计数法，使用了一组不同长度的正比计数器。原始的85氪气体被稀释了2×10⁵倍，以便达到正比计数器适用的活度浓度。引入了一种基于大容积气球和重量法测定稀释体积且不确定度较小的新稀释方法。
