Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Soma, Yasutaka; Kato, Chiaki; Ueno, Fumiyoshi; Aoki, So; Inagaki, Hiromitsu*
no journal, ,
Crevice environment was measured by electrochemical sensors in high temperature pure water. Crevice environment and surface oxide layer on the crevice surface was analyzed in terms of crevice's geometrical factors (crevice gap, g and depth, d). The results were plotted on the g-d plane. It was shown that electrical conductivity of crevice solution was very high in oxygen depleted zone and the zone shrinked with increasing crevice gap, g.
Soma, Yasutaka; Ueno, Fumiyoshi; Inagaki, Hiromitsu*
no journal, ,
Effect of crevice geometry on corrosion environment within crevice of stainless steel in high temperature water was studied.
Soma, Yasutaka; Komatsu, Atsushi; Ueno, Fumiyoshi; Inagaki, Hiromitsu*
no journal, ,
Corrosion condition within crevice of stainless steel is important to understand dissolution mechanisms of crack tip of stress corrosion cracking (SCC) in high-temperature water. We have reported that electrical conductivity of solution within crevice of stainless steel (crev) exposed to high temperature and high purity water containing sufficient dissolved oxygen (DO) become more than 2 orders of magnitude higher than that for bulk pure water. In this study effect of conductivity and DO concentration of bulk water on crev of Type-316L stainless steel have been studied in 288C water. Following conclusion have been obtained: (1) crev increased with increasing DO concentration from 3 ppb to approximately 300 ppb. Above 300 ppb, crev did not simply increased with DO concentraion. (2) maximum crev was not affected by bulk water conductivity suggested that crev would be determined by chemical equilibrium reaction. (3) crev-time curves were not affected by crevice depth. It was assumed that anion required to increase crev generated within the crevice.
Nakahara, Masaumi; Watanabe, So; Kimura, Shuya; Sasaki, Misaki*; Inagaki, Hiromitsu*; Moriguchi, Tetsuji*
no journal, ,
A novel removal technique with ultra-fine bubbles has been proposed for decommissioning of nuclear facilities. The performance of removal technology with ultra-fine bubbles was evaluated in cold experiments with simulated contaminants precipitated Co oxides and hot experiments with radioactive contaminants.