title: A multiscale wavelet data treatment for reliable localization of inflection points for analytical purposes.
abstract: Instrumental analysis techniques that employ measurements based on inflection points may have their accuracy compromised due to the need for signal differentiation, which is very sensitive to instrumental noise. This paper presents a strategy for localizing inflection points that exploits the multiscale processing capability of the Wavelet Transform and avoids the need for explicit signal differentiation. The strategy is illustrated in simulated examples and also in a real analytical problem involving the determination of Pb and Cd by potentiometric stripping analysis. In this application, the results were in good agreement with the expected values and were slightly better than those obtained from the first derivative of the curves after smoothing by a Windowed Fourier Transform.
authors: Departamento de Química Fundamental, Universidade Federal de Pernambuco, CCEN, CEP 50740-901 - Recife PE, Brazil.
authors: Valdomiro Lacerda
authors: VL
authors: Martins
authors: Luciano Farias
authors: LF
authors: de Almeida
authors: Suzana Limeira
authors: SL
authors: de Castro
authors: Roberto Kawakami Harrop
authors: RK
authors: Galvão
authors: Mário César Ugulino
authors: MC
authors: de Araújo
authors: Edvan Cirino
authors: EC
authors: da Silva