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lead tetraoxide
tetróxido de chumbo

trimanganese tetraoxide
tetróxido trimanganoso

dinitrogen tetraoxide [2]
tetraóxido de diazoto [2]

barium diboron tetraoxide
tetróxido de bário e diboro

dialuminium nickel tetraoxide; [1]
tetraróxido de dialumínio e níquel; [1]

triiron tetraoxide (ci 77489, 77491, 77492, 77499).
tetraóxido de triferro (ci 77489, 77491, 77492, 77499)

this means that the usual need to stain polymers for enhanced contrast in the tem (typically done with osmium or ruthenium tetraoxide) may not be necessary with the low voltage electron microscopy technique.
this means that the usual need to stain polymers for enhanced contrast in the tem (typically done with osmium or ruthenium tetraoxide) may not be necessary with the low voltage electron microscopy technique.

catalyst, consisting predominantly of dichromium copper tetraoxide and copper (ii) oxide, containing by weight 38 % or more but not more than 48 % of copper, evaluated as copper (ii) oxide, fixed on a support of silicon dioxide, for the hydrogenation of acetophenones [1]
catalisador constituído essencialmente por tetraóxido de dicrómio e cobre e óxido de cobre (ii), contendo, em peso, 38 % ou mais, mas não mais de 48 % de cobre, expresso em óxido de cobre (ii), fixado num suporte de dióxido de silício, destinado ao hidrogenação de acetofenonas [1]