【摘要】 在0.02 mo1/L六次甲基四胺缓冲溶液中(pH 5.5),铜(Ⅱ)-6-苄基氨基嘌呤(6-BA)在KNO3存在下,于-0.50 V左右(vs.SCE)产生一尖锐、灵敏的二次导数极谱波,其峰电流与6-BA浓度在3.0×10-5~1.0×10-6mo1/L范围内呈线性关系,检出限为9.0×10-7mo1/L。与铜(Ⅱ)浓度在1.0×10-5~3.0×10-7mo1/L范围内呈线性关系;检出限为1.0×10-7mo1/L。研究了该波的性质及电极反应机理,证明该波为络合吸附波。铜(Ⅱ)与6-BA的组成比为1∶1;电子转移数n=2;α=0.58;反应速率常数Ks=1.81/s。方法用于绿豆、大米和玉米样品中铜的测定,结果满意。更多还原

【Abstract】 In 0.02 mo1/L hexamethylene-tetramine buffer solution（pH 5.5）,a sensitive second derivative polarographic wave of Cu（Ⅱ）-6-benzyl aminopurine（6-BA） complex appears at-0.50 V（vs.SCE）.The peak current is proportional to 6-BA concentration in the range of 3.0×10^-5～1.0×10^-6 mo1/L,the detection limit is 9.0×10^-7 mo1/L.The peak courrent is also proportional to Cu（Ⅱ） concentration in the range of 1.0×10^-5～3.0×10^-7 mo1/L,the detection limit is 1.0×10^-7 mo1/L.Several electrochemical methods have been used to study the properties of the wave and the reaction mechanism of electrode.It is proved that the wave is a complex adsorptive one.The molar ratio of Cu（Ⅱ） to 6-BA is 1∶1.The number of electrons transferred（n） is 2 and the transfer coefficient （α） is 0.58 and the rate constant of surface electrode reaction（K_s） is 1.81/s.This method has been successfully applied to the determination of Cu（Ⅱ） in mung bean,rice and maize.更多还原