阿达玛变换在示波计时电位法中的应用

APPLICATION OF HADAMARD TRANSFORM TO OSCILLOCHRONOPOTENTIOMETRY

报导了阿达玛变换在示波计时电位法中的应用．在 Ｎａ Ｏ Ｈ－ Ｐｂ２ ＋ 、 Ｋ Ｃｌ－ Ｃｄ２ ＋ 和 Ｌｉ Ｃｌ － Ａｌ３ ＋ 体系中，考察了两种示波计时电位曲线的阿达玛谐波电位同去极剂浓度 Ｃｏ  的关系．实验结果表明：对经典示波计时电位曲线ｄ Ｅ／ｄｔ－ Ｅ，一次谐波 Ｅ１ 随 Ｃｏ  增加而线性下降，二次谐波 Ｅ２ 与 Ｃｏ  成正比；而在示波伏安ｉｆ － Ｅ 曲线中，此规律则相反．这些线性关系可用于定量分析测试．同 Ｆｏｕｒｉｅｒ 变换相比，阿达玛变换具有运算速度快。

The application of Hadamard transform to oscillochronopotentiometry was reported in this paper.By using the technique of Fast Hadamard Transform(FHT),the Hadamard harmonic potentials for both a. c. oscillochronopotentiometry and oscillovoltammetry were obtained.The relations between the primary and the secondary harmonic potentials( E 1 / E 2 )and the depolarizer concentrations Co * were studied in three different systems for 1 mol·L -1 NaOH-Pb 2+ ,1 mol·L -1 KCl-Cd 2+ and 1 mol·L -1 LiCl-Al 3+ .The experimental results indicate that:the primary harmonic potentials E 1 linear decreases with increase of Co * and the secondary harmonic potential E 2 is directly proportional to the Co * with three different slope degrees for the classical oscillochronopotentiometric d E /d t-E curve.But this relation is on the contrary for oscillovoltammetric i f-E curve.In the qualitative analysis measurement these conclusions are interesting and they can be applied in the live oscillovoltammetry.Compared with the Fourier transform,FHT has the distinguished advantages of fast speed and better suitableness for digital signal analyses.In the case of the signal with large change FHT is more powerful than other fast transformation.