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(Sigma–Aldrich) and agitated for 3 h, while the
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butylamine in acetonitrile (0.05 cm3/min). Electrode
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420 A digital meter and a double-junction electrode.
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on the samples with a scan rate of 3 °/min up to
600 °C.
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Acknowledgments Financial support (project number 8058) by the
deanship of scientific research at King Faisal University is gratefully
acknowledged.
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