Methods for chemical analysis of tantalum and niobium—Part 11:Determination of arsenic,antimony,lead,tin and and bismuth contents in niobium—Direct current arc atomic emission spectrometry
Methods for chemical analysis of tantalum and niobium—Part 10:Determination of iron,nickel,chromium,titanium, zirconium,aluminum and manganese contents in niobium—Direct current arc atomic emission spectrometry