Appendix 1.
Values obtained for reference material NIST 2387 determined by energy dispersive X-ray fluorescence. Values expressed in ng/cm2.
| Certified values | Determined values | ||||
|---|---|---|---|---|---|
| Elements | Mean | SD | Mean | SD | RE |
| Al | 2330.32 | 53.21 | 2004.8 | 16.36 | -13.97 |
| Ca | 1325.3 | 170.7 | 1104.3 | 13.97 | -16.67 |
| Cu | 40.56 | 4.22 | 38.74 | 1.55 | -4.5 |
| Fe | 2660.64 | 160.6 | 3413.7 | 176.42 | 28.3 |
| K | 530.12 | 52.21 | 434.78 | 8.72 | -17.99 |
| Na | 186.75 | 10.04 | 119.38 | 10.56 | -36.07 |
| Ni | 6.83 | 1.2 | 6.18 | 1.15 | -9.44 |
| Pb | 31.83 | 5.42 | 22.67 | 7.58 | -28.78 |
| S | 105.42 | 26.1 | 87.77 | 0.93 | -16.75 |
| Si | 5883.53 | 160.6 | 4956.7 | 12.41 | -15.75 |
| Ti | 149.6 | 24.1 | 128.12 | 52.11 | -14.36 |
| V | 4.87 | 0.6 | 4.5 | 1.6 | -7.63 |
| Zn | 179.72 | 13.05 | 155.63 | 3.08 | -13.4 |
SD, Standard Deviation; RE, Relative, Error