著者

瀬尾 眞浩

出版者

公益社団法人 腐食防食学会

雑誌

Zairyo-to-Kankyo (ISSN:09170480)

巻号頁・発行日

vol.61, no.9, pp.341-348, 2012-09-15 (Released:2013-03-01)

参考文献数

44

被引用文献数

3 5

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アンダーポテンシャル析出(UPD)とは,水溶液中の金属イオンMz+が金属Mとして析出する平衡電位よりも貴な電位領域で異種金属M'上に析出する現象である.UPDの一般的特徴について述べ,UPDが起きる電位領域の幅はM'とMの仕事関数の差に比例することを強調した.また,酸素還元反応,水素発生反応および金属腐食反応に及ぼすUPDの影響について述べ,反応機構に及ぼすUPD金属の役割を説明した.特にNi 基合金の微量Pbによる応力腐食割れに関連して,PbのUPDがNiの腐食に及ぼす影響について詳しく紹介した.さらに,UPD層の吸着構造から表面合金構造への変化やUPD金属と電解質アニオンの共吸着構造についても触れ,反応機構に及ぼすUPD金属の役割を明らかにするには電極界面のその場解析の重要性を指摘した.

著者

馬場 文雄 鈴木 紹夫 瀬尾 眞浩

出版者

公益社団法人 腐食防食学会

雑誌

Zairyo-to-Kankyo (ISSN:09170480)

巻号頁・発行日

vol.45, no.10, pp.588-594, 1996-10-15 (Released:2009-11-25)

参考文献数

13

被引用文献数

3 1

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Effects of ferrous ions on the shape and activity of sulfate-reducing bacteria (SRB) have been investigated using a phase-difference microscope, hydrogen sulfide gas detector, and measuring the amount of ferrous sulfide in the medium. SRB changed its shape at an interval of several hours as the culturing time increased. At the time of maximum activity of SRB, SRB evolved a significant amount of hydrogen sulfide and changed from rod like shape to comma like shape. After this period, pH of the medium increased above 9.0 and the size of SRB became less with reduced evolution of hydrogen sulfide. Even if some amount of HCl was added to keep pH of the medium at 7.0, the hydrogen sulfide evolution was not recovered. In the medium with high concentration (0.01mol kg-1) of ferrous ions, colloidal substance were present and seemed to provide a comfortable place for SRB to grow, ripen, and split easily. In the medium with low concentration (0.00036mol kg-1) of ferrous ions, the colloidal materials were few and the number of SRB was less than that in the high concentration (0.01mol kg-1) medium. It is concluded that ferrous ions do not only affect directly the metabolism of SRB, but also form the colloidal substance on which SRB can keep alive easily.

著者

馬場 文雄 鈴木 紹夫 瀬尾 眞浩

出版者

Japan Society of Corrosion Engineering

雑誌

Zairyo-to-Kankyo (ISSN:09170480)

巻号頁・発行日

vol.44, no.11, pp.606-611, 1995-11-15 (Released:2009-11-25)

参考文献数

18

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Effects of ferrous ions on the growth and activity of sulfate-reducing bacteria (SRB) have been investigated using biological and analytical techniques for a better understanding of its metabolism in corrosive media with high contents of metal ions. In-situ gravimetry by the quartz crystal microbalance (QCM) technique was also applied to examine the sulfide-producing process in the medium. The growth of SRB increased with increasing ferrous ion concentration up to 0.01M and retarded above 0.01M. In the low concentration region (0.00036M-0.01M) ferrous ions enhanced the growth of SRB, whereas in the high concetration region (0.03M-0.7M) ferrous ions gave the opposite effect due to high osmotic pressure. The FeS producing ability was closely related to the growth of bacteria, therefore it seems that SRB accelerates the corrosion of metal in the medium including 0.01M ferrous ions. QCM technique was able to detect sensitively the amount of FeS attached on the electrode surface, which was proportional to the total amount of FeS in the medium. Thus it was found that QCM technique is powerful for monitoring the FeS producing process.