Table 1.
Uncertainty Budget for spICP-MS Determination of PNCdirect of NIST RM 8012 and RM 8013, Respectively
| RM 8012 (PNCdirect 2.38 × 1014 L−1) |
RM 8013 (PNCdirect 3.16 × 1013 L−1) |
|
|---|---|---|
| source of uncertainty | relative contribution (%) | relative contribution (%) |
| particle size consensus value for standard (dNP RM) | 4.2 | 44.3 |
| dilution factor of stock suspension for the sample (Dil.F) | 1.8 | 0.6 |
| measurement repeatability (Rep) | 6.6 | 3.8 |
| number of observed events for the sample (NNP) | 54.9 | 16.7 |
| Au mass fraction of the standard (CS) | 0.9 | 0.2 |
| sample uptake rate for the standard (qliq RM) | 0.6 | 0.3 |
| time of acquisition for the standard (taq RM) | <0.0 | <0.0 |
| number of observed events for the standard (NNP RM) | 29.1 | 32.3 |
| sample uptake rate for the sample (qliq) | 0.6 | 0.3 |
| time of acquisition for the sample (taq) | <0.0 | <0.0 |
| dilution factor of stock suspension for the standard (Dil.FRM) | 1.1 | 1.0 |
| density of the particles (ρ) | <0.0 | <0.0 |
| residual | 0.2 | 0.5 |
| combined standard uncertainty (L−1) | 0.4 × 1013 | 0.4 × 1012 |
| expanded k =2 uncertainty (L−1) | 0.7 × 1013 | 0.7 × 1012 |