Hitachi ZA3000 Series, Инструкция по эксплуатации

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(3) Preparation for measurement of selenium
Sample preparation is exemplified below.
(a) Standard solutions for working curve
(selenium: 0, 5, 10, 15 ug/L)**
a. Hydrochloric acid :
4 mL
b. 1 mg/L selenium standard solution : 0, 50, 100, 150 uL
Add a and b, and adjust the total volume to 20 mL with pure
water.
(b) Sample
a. Hydrochloric acid : 4 mL
b. Sample solution : 10 mL
Add a and b, and adjust the total volume to 20 mL with pure
water.
** Actual concentrations are 0, 2.5, 5.0 and 7.5 ug/L.
However, 0, 5, 10, and 15 ug/L values are required for
condition input, since sample is to be diluted twofold.
NOTE 1: When Se is measured after As measurement, the
absorbance of Se may decrease because of KI remained
in the flow channel. In case of measurement for both of
As and Se, measure Se first whenever possible. When Se
has to be measured after As measurement, wash the flow
channel by aspirating HCl solution (e.g. 1.0 mol/L) for
about 10 min.
NOTE 2: When the measurement is continued for long time (more
than 1 h), the absorbance may decrease because of
absorption of analyte into dew inside of the silicone tube
(This will be prominent for Se). In this case, remove the
silicone tube and dry it, then attach again.