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The authors thank the National Science Council, Taiwan, for
the financial support under Contract NSC 92-2211-E-007-
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Supporting Information Available
Redox potentials as a function of Fe(II) concentration in the
presence of 0.5 mM Cu(II) (Figure S1); XRD patterns of the
precipitates at various pH values (Figure S2); redox potentials
of the Fe(II)-amended aqueous solutions at various pH values
in the presence and absence of Cu(II) (Figure S3); SEM images
of ferric oxides produced from the reaction of Fe(II) and
Cu(II) at various pH values (Figure S4). This material is
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