Table 2.
Coefficients for the determination of the uncertainty of the pathlength of SRM 2082 utilizing Eq. (9) for component A (tryptophan) and component B (uracil) at 280 nm and 260 nm, respectively. The constant u(Ec) corresponds to the uncertainty of Eq. (1) and Eq. (2). Coefficients au2, au1, and au0 are used in Eq. (5) to map the uncertainty of change in absorbance due to temperature, u(ΔtA). Coefficients bu3, bu2, bu1, and bu0 are from Eq. (6) for the uncertainty of the change in absorbance from the spectral bandwidth, u(ΔBA). Refer to the SRM 2082 certificate of analysis for further guidance.
| Tryptophan A280 | Uracil A260 | |
|---|---|---|
| u(Ec) | 0.000 297 | 0.000 304 |
| au2 | 1.2271 × 10−10 | 1.0671 × 10−10 |
| au1 | −5.7849 × 10−9 | −5.0309 × 10−9 |
| au0 | −7.0128 × 10−8 | 6.0988 × 10−8 |
| bu4 | 7.4002 × 10−9 | 1.3126 × 10−9 |
| bu3 | −9.1491 × 10−8 | −1.6227 × 10−8 |
| bu2 | 3.9443 × 10−7 | 6.9996 × 10−8 |
| bu1 | −6.7305 × 10−7 | −1.1970 × 10−7 |
| bu0 | 4.3012 × 10−7 | 7.6621 × 10−8 |