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  _____      ___      ______    _____    _    _   
 / ____||   / _ \\   /_   _//  |  ___|| | \  / || 
/ //---`'  / //\ \\    | ||    | ||__   |  \/  || 
\ \\___   |  ___  ||  _| ||    | ||__   | .  . || 
 \_____|| |_||  |_|| /__//     |_____|| |_|\/|_|| 
  `----`  `-`   `-`  `--`      `-----`  `-`  `-`

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Text this: Spinel manganese ferrites for oxygen electrocatalysis : effect of Mn valency and occupation site