Research On Uncertainty Propagation Model Of Determination Of Lead And Copper In Groundwater By Graphite Furnace Atomic Absorption Spectrometry

In view of domestic chemical testing laboratories in evaluation and expression ofuncertainty of measurement, the calibration curve fitting methods are all simpleregression. It ignores the influence that involved by the uncertainty of each calibrationpoints. In this paper, the standard methods for determination of copper and lead in waterwere collected and analyzed, the geological industry standard “DZ/T0064.21-1993methods for examination of underground water-determination of copper and lead bygraphite furnace atomic absorption spectrometry(GF-AAS)” was selected as an example.A calculating method of fitting uncertainty was put forward. Uncertainty propagationmodel was introduced in the fitting of standard curves in chemical analysis. This modelused each point’s error as the weight and fitting the curve with double-error regression.Uncertainty propagation was correctly and effectively when the fitting of standard curve.It ensured the reliability and comparability of the measurement results.Using standard points X, responses Y and their uncertainties double-errorregression was conducted which is the scientific research achievements of the project. Itcan make the uncertainty propagation reasonable and effective when the standard curveregresses. Combined with other main influencing factors, the measurement uncertaintyof determination of copper and lead was evaluated by GF-AAS, and the uncertaintypropagation model was established. Using this model could get the results withuncertainty, and calculate the method detection limit under given error. Compared withtraditional detection limit, it is much quicker and more reasonable.