title: Application of rational functions for the standard addition method.
abstract: Some rational functions are considered as the basis for calculation of unknown concentration (x0) of an analyte X determined according to the standard addition method (SAM). The correction for dilution of the sample tested during addition of successive increments of standard(ised) solution of X is involved in the related algorithm applied for calculation of the x0 value. The formulae derived were put in context with experimental data, obtained according to the AAS method from Cu-measurements in samples obtained by digestion of an ash obtained from incinerated sludge. It was stated that the use of rational functions for modeling purposes strengthens the robustness of the results thus obtained.
authors.affiliation: Faculty of Engineering and Chemical Technology, Technical University of Cracow, 31-155 Cracow, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Gorazda
authors.forename: Anna M
authors.initials: AM
authors.lastname: Michałowska-Kaczmarczyk
authors.forename: Agustin G
authors.initials: AG
authors.lastname: Asuero
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Michałowski
mesh_terms: D000465:Algorithms; D002849:Chromatography, Gas; D003300:Copper / Q000302:isolation & purification*; D006801:Humans; D017745:Incineration; D007201:Indicator Dilution Techniques; D017711:Nonlinear Dynamics; D012722:Sewage / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D012722:Sewage; D014874:Water Pollutants, Chemical; D003300:Copper
keywords: AAS; Nonlinear modeling; Standard addition method