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线性变势吸附伏安法是一种简便的痕量分析方法。本文讨论了此方法中不可逆过程的峰电流方程式,并对其作了验证。仪器与试剂 83-2.5型多阶自动新极谱仪(各档灵敏度已校正),LZ_3-100型函数记录仪,Metrohm E410型悬汞电极,所用试剂同文献[1]。实验方法在含0.1mol/dm~3NH_3/NH_4Cl,1×10~(-4)mol/dm~3丁二肟,pH=9.2的Co(Ⅱ)溶液中用氮气除氧并搅拌。由于配合物的稳定常数很大(β=10~(17)),可以认为Co(Ⅱ)A_2的浓度等于Co(Ⅱ)的浓度。由于电势负于-1.20V时Co(Ⅱ)A_2在电极上不吸附,因此先将电极置于-1.5V,一当从悬汞电极中旋出新的汞滴,立即将电势恒定于-0.8V,富集一定时间,然后关闭搅拌器,30秒后,电势以100mV/s的速度向负方向扫描至-1.3V,同时
Linear variation of adsorption voltammetry is a simple method of trace analysis. In this paper, the peak current equation of irreversible process in this method is discussed and validated. Instruments and reagents 83-2.5 multi-order automatic new polarimeter (each file sensitivity has been corrected), LZ_3-100 type function recorder, Metrohm E410 hanging mercury electrode, reagents used in the literature [1]. Experimental Methods The Co (II) solution containing 0.1 mol / dm ~ 3NH_3 / NH_4Cl and 1 × 10 ~ (-4) mol / dm ~ 3 butanedioxime and pH = 9.2 was deoxygenated with nitrogen and stirred. Due to the large stability constant of the complex (β = 10 ~ (17)), the concentration of Co (Ⅱ) A 2 can be considered as the concentration of Co (Ⅱ). Since Co (II) A 2 is not adsorbed on the electrode when the potential is negative at -1.20 V, the electrode is first placed at -1.5 V and once a new drop of mercury is spun off from the hanging mercury electrode, the potential is immediately stabilized at -0.8 V, enrich for a certain period of time, and then turn off the stirrer. After 30 seconds, the potential was swept to -1.3 V at a rate of 100 mV / s in the negative direction while