將鋼樣(0.25克)溶於20毫升HCl+5毫升HClO_4內,並將此溶液蒸發到發生濃煙为止,过程須進行到殘渣內只有微量的HClO_4。冷却殘渣,並溶於40毫升的試劑內撛噭┛捎?7.5克乙二胺四醋酸溶入NaOH內而製得,NaOH的用量須使溶液以酚酞作指示劑時呈酸性。此後,在溶液內添加50克MgSO_4以使Ti~(4+)加快沉澱,隨即將它冲淡到1升。在添加40毫升試劑之後,分析用溶液便呈中性,以後还須多加NH_4OH,使其 The steel sample (0.25 g) was dissolved in 20 ml of HCl + 5 ml of HClO_4 and this solution was evaporated until heavy smoke had occurred. The process had to be carried out until there was only traces of HClO_4 in the residue. The residue is cooled and dissolved in 40 ml of reagent. The solution is prepared by dissolving 7.5 g of ethylenediaminetetraacetic acid in NaOH. The amount of NaOH should be such that the solution is acidic with phenolphthalein as an indicator. Thereafter, 50 g of MgSO 4 was added to the solution to accelerate the precipitation of Ti 4+, which was then diluted to 1 liter. After adding 40 ml of reagent, the analytical solution will be neutral, after more NH_4OH must be added to make it