Robustness of Ammonium Hydroxide Concentration on Accuracy for Elemental Tungsten Quantification
| Ammonium hydroxide with Tungsten Spike | Syringe Extract | ||||
|---|---|---|---|---|---|
| None | 0.5 μg/L W | 10 μg/L W | 180 μg/L W | ||
| W in 0.50% NH4OH (μg/L) | <0.1* | 0.5 | 10.0 | 180.4 | 6.1 |
| W in 0.45% NH4OH (μg/L) | <0.1* | 0.5 | 10.1 | 180.2 | 6.5 |
| W in 0.55% NH4OH (μg/L) | <0.1* | 0.5 | 9.9 | 179.2 | 6.4 |
| Precision (RSD, %) | N/A | <1 | 1 | <1 | 3 |
↵* Less than LOQ (0.1 μg/L).