Attention has focused on a Ni aluminide containing a small amount of Y as a high oxidation resistant material, and preparation of a coating consisting of this material was attempted by the molten salt electrodeposition which is a low cost coating method. In the present study, the preparation of the coating consisting of this material was carried out by the electrodeposition of Ni using an aqueous solution as the electrolyte and the electrodeposition of Y and Al using a molten salt electrolyte. Furthermore, in order to change the depth of the region containing Y in the Ni aluminide layer, a three step electrodeposition of Ni, Y and Ni was carried out, and the times of the first and third Ni electrodepositions were changed. As a result, surface layers consisting of Ni aluminide with a different depth of the region containing Y were formed. Furthermore, the cyclic oxidation resistance of these specimens was examined in air at 1423 K. As a result, for the specimen with a shallow Y containing region in the Ni aluminide layer, the specimen mass reduction due to spalling of the scale was observed, whereas for the specimen with a deep Y containing region, no specimen mass reduction was observed and a high cyclic oxidation resistance was obtained. For the specimen with a deep Y containing region, which showed the high cyclic oxidation resistance, the scale formed on the coating after the oxidation test consisted of Al 2 O 3 containing Y 2 O 3 , and this scale entered the metal substrate under the scale in the form of a wedge.
The preparation of a coating consisting of Ni aluminide containing a small amount of Hf was carried out by the electrodeposition of Ni using an aqueous solution and the electrodeposition of Hf and Al using a molten salt. Furthermore, in order to change the depth of the layer containing Hf in the coating, a four-step electrodeposition of Ni, Hf, Ni and Al was carried out, and the times of the first and third Ni electrodepositions were changed. As a result, coatings consisting of Ni aluminide, which contained different depths of the Hf-containig layer, were formed. The cyclic-oxidation resistance of these specimens was evaluated in air at 1423 K. For the specimen with a shallow Hf-containing layer in the coating, the specimen mass reduction due to spallation of the scale was observed, whereas for the specimen with a deep Hfcontaining layer, the specimen mass reduction was only slightly observed and a high-cyclic oxidation resistance was obtained. Among the specimens with a deep Hf-containing layer, the specimen prepared by Hf deposition for 0.6 ks showed the highest cyclic-oxidation resistance. For this specimen, the scale formed on the coating after the oxidation test consisted of Al 2 O 3 . This scale was adhesive, and locally entered the metal substrate.
We studied the association of a Cu tolerant mycobiont, Tremolecia atrata (rusty-rock lichen) with Cu. T. atrata mycobiont cell aggregates, which grew into a sperical shape, rapidly absorbed Cu into their inner and outer parts. The EDS/SEM study showed that Cu was more highly accumulated in the inner part than the outer part of the aggregates. The XANES study revealed that the Cu absorbed by the T. atrata mycobiont was both monovalent and divalent. These results suggested that the T. atrata mycobiont's high tolerance to Cu is attributable to its ability to store Cu(I) inside the cytoplasm and to adsorb Cu(II) on the cell wall.
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