The results of conditional experiments.

Purpose	Conditions		δ 66Zn	2SD	δ 68/64Zn	2SD	Times
The effect of Zn/Cu	Zn concentration (ppb)	Cu concentration (ppb)
	300	100	−0.06	0.05	−0.17	0.09	3
		200	0.04	0.05	0.07	0.06	3
		250	0.06	0.03	0.12	0.05	3
		300	0.08	0.06	0.15	0.09	3
The effect of Zn concentration	Zn/Cu	Zn concentration (ppb)
	2 : 1	60	0.67	0.04	0.62	0.10	3
		100	0.49	0.06	0.53	0.20	3
		150	0.16	0.06	0.15	0.03	3
		200	0.10	0.10	0.10	0.15	3
		250	0.01	0.02	0.00	0.10	3
		350	−0.03	0.03	−0.02	0.09	3
		400	−0.05	0.03	−0.05	0.14	3
		600	−0.09	0.02	−0.06	0.08	3
		900	−0.13	0.03	−0.09	0.01	3
The effect of Ni concentration	Ni concentration (ppb)
	0.1		0.00	0.04	−0.01	0.08	3
	0.5		−0.01	0.04	0.01	0.16	3
	1		−0.03	0.09	−0.04	0.11	3
	5		−0.01	0.03	0.07	0.02	3
	10		−0.01	0.02	0.02	0.01	3
	40		−0.04	0.03	−0.06	0.10	3
	60		0.01	0.08	−0.02	0.18	3
	80		0.00	0.09	−0.03	0.07	3
	100		0.01	0.09	0.02	0.08	3
	150		0.02	0.04	0.01	0.14	3
The effect of solution acidity	Solution acidity (m/m%)
	0.042		−0.20	0.07	−0.42	0.11	3
	1.0		−0.08	0.08	−0.14	0.21	3
	1.5		−0.06	0.06	−0.11	0.07	3
	2.2		0.02	0.03	0.09	0.03	3
	2.5		0.02	0.04	0.06	0.04	3
	3.0		0.01	0.03	0.10	0.05	3