论文部分内容阅读
在(CH)_6N_4-HCl缓冲溶液中(pH5.6),当有NaNO_2存在时,Zn(Ⅱ)-2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚络合物有一灵敏的吸附波,峰电位在-0.448V(vs.SCE)左右,该波的二阶导数峰峰电流与锌质量浓度在6.8×10~(-9)-1.69×10~(-7)mol/L范围内呈线性关系(r=0.9989,n=10)。检出限为0.001mg/L。本方法回收率在95.1%—104.9%之间。经多种电化学方法证明该波为络合物吸附波,其电极过程为不可逆过程。此外还试验了多种离子对峰电流I_P″的影响。所拟定的方法可用于红枣中微量锌(Ⅱ)的测定。
Zn (Ⅱ) -2- (5-bromo-2-pyridylazo) -5-diethylaminophenol in the presence of NaNO_2 in (CH) _6N_4-HCl buffer solution There is a sensitive adsorption wave with a peak potential of -0.448V (vs.SCE). The second derivative peak current and zinc concentration of this wave are in the range of 6.8 × 10 -9 -9.69 × 10 -7, mol / L linear relationship (r = 0.9989, n = 10). The detection limit was 0.001mg / L. The recovery rate of this method is between 95.1% and 104.9%. A variety of electrochemical methods to prove that the wave is complex adsorption wave, the electrode process is irreversible process. In addition, the effects of various ions on the peak current I_P "were also tested.The proposed method can be used for the determination of trace zinc (Ⅱ) in red dates.