1
50 J. Phys. Chem. A, Vol. 115, No. 2, 2011
Koga and Sato
supports qualitatively the interpretation of the exothermic
phenomenon deduced from the TG-DTG-DTA curves in Figure
be stabilized in confinement by the outer shell of surface product
layer and the internal residue of FeC
the outer shell of amorphous Fe induces the crystallization
of internal amorphous Fe and the oxidative decomposition
of residual FeC
2 4
O . The crystallization of
1
6, that is, the phenomenon results from an overlapped process
of the crystallization of amorphous Fe and the oxidative
decomposition of residual FeC induced by the crystallization
of Fe . The systematic increase of E value in the range R >
.2 is likely the apparent result from the participation of the
oxidative decomposition of the residual FeC to the preceding
crystallization of amorphous Fe . The concave-shaped rate
behavior in the second half of the overall process with the drastic
increase in E at the end can be explained by the ending of the
2 3
O
2
O
3
2 3
O
O
2 4
2 4
O .
2
O
3
a
0
Acknowledgment. The present work was supported partially
by a grant-in-aid for scientific research (B) (21360340 and
22300272) from Japan Society for the Promotion of Science.
2 4
O
2
O
3
a
References and Notes
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(
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