Pollard等和Hnilickova等曾提及钛与4(2-吡啶基偶氮)间苯二酚(以下简称PAR)的定性反应。Sommer等在比较测定钛的试剂时,也提及PAR,但均无详细报导。Sweeter等报告在过氧化氢存在下,钛与EDTA生成新的络合物,武者等定其组成,并用于分光光度测定和光度滴定钛。小友也报告在过氧化氢存在下,用二甲酚橙分光光度测定钛。本文探讨PAR及PAR-过氧化氢的作 Pollard et al. And Hnilickova et al. Have referred to the qualitative reaction of titanium with 4 (2-pyridylazo) resorcinol (hereinafter referred to as PAR). Sommer et al. Also referred to PAR when comparing titanium reagents, but none were reported in detail. Sweeter et al. Report the formation of new complexes of titanium with EDTA in the presence of hydrogen peroxide, which are used for spectrophotometric and photometric titration of titanium. Xiao also reported in the presence of hydrogen peroxide, with xylenol orange spectrophotometric determination of titanium. This article discusses the PAR and PAR-hydrogen peroxide for