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研究了在1 mol/L磷酸介质中，钒(V)对KIO4氧化靛蓝胭脂红褪色反应的催化作用及草酸钠的活化作用，建立了一种测定钒的方法。无草酸钠时该体系为准零级反应，表观活化能为76.7 kJ/mol，在22℃时钒量在0～5mg/L范围内与?A呈线性，检出限为0.1 mg/L。在草酸钠存在下则为准一级反应，表观活化能为60.1 kJ/mol，钒量在0～mg/L范围内与1g(A0/A)呈线性，检出限为0.02mg/L。提高介质酸度，可显著降低反应温度。在NaF及尿素存在下，大多数常见离子无干扰。本法简便快速，选择性和灵敏度较高，用于钢中微量钒的直接测定，结果满意。
The catalytic effect of vanadium (V) on the fading reaction of KIO4-oxidized indigo carmine and the activation of sodium oxalate were studied in 1 mol / L phosphoric acid medium. A method for the determination of vanadium was established. In the absence of sodium oxalate, the system is a quasi-zero-order reaction with an apparent activation energy of 76.7 kJ / mol and a linear relationship with A at 0-5 mg / L at 22 ℃ with a detection limit of 0.1 mg / L. In the presence of sodium oxalate, it is a quasi-first order reaction, with an apparent activation energy of 60.1 kJ / mol and a vanadium content of 1 mg (A0 / A) in the range of 0 to mg / L with a detection limit of 0.02 mg / L . Improve the acidity of the medium, can significantly reduce the reaction temperature. In the presence of NaF and urea, most common ions do not interfere. This method is simple, rapid, selective and sensitive for the direct determination of trace vanadium in steel with satisfactory results.