Beam-palarization asymmetries for the (,) and (,) reactions for =1.5-2.4 GeV

Zegers, R. G. T.*; Sumihama, Mizuki*; Ahn, D. S.*; Ahn, J. K.*; Akimune, Hidetoshi*; Asano, Yoshihiro; Chang, W. C.*; Dat, S.*; Ejiri, Hiroyasu*; Fujimura, Hisako*; et al.

Physical Review Letters, 91(9), p.092001_1 - 092001_4, 2003/08

https://doi.org/10.1103/PhysRevLett.91.092001

no abstracts in English

A Study for localization of corrosion on carbon steel overpack

Taniguchi, Naoki; ; Kawasaki, Manabu*; *; *

JNC TN8400 99-067, 119 Pages, 1999/10

JNC-TN8400-99-067.pdf:8.25MB

Carbon steel is one of the candidate materials for overpacks for high level radioactive waste disposal in Japan. The estimation of corrosion allowance needs to clarify the localization of corrosion. One of the most extreme case of the localization under oxidizing condition at the initial stage of repository is considered to be localized corrosion such as pitting and crevice corrosion due to the break down of passive film formed on the metal surface. In this study, the critical condition for the initiation and the propagation behavior of pitting and crevice corrosion were assessed by the experimental study. The results of the electrochemical experiments in carbonate-chloride aqueous solution showed that carbon steel have high sensitivity for the pitting and crevice corrosion in passive region. The propagation behavior of pitting and crevice corrosion was studied by the immersion tests under aerated condition. The results of the immersion tests showed that the degree of localization became small and seemed to be like general corrosion in appearance as the localized corrosion propagate. The extreme value statistical analysis were applied to the corrosion depth measured in the immersion tests. Based on the analysis, it was concluded that the equation for maximum corrosion depth due to oxygen obtained in our previous study would give conservative assessment even in the assumption of propagation of pitting corrosion or crevice corrosion. The localization of corrosion for carbon steel under reducing condition after consumption of oxygen was also estimated. The external current was supplied to the carbon steel specimens in compacted bentonite to accelerate the corrosion and corrosion depth were measured for each specimens and extreme value statistical analysis were applied to the results. The pitting factor became small as the average corrosion depth became large. Assuming that the average corrosion depth in 1000 years is 5 10mm, the pitting factor is ...