title: Robust estimation of thermodynamic parameters (ΔH, ΔS and ΔCp) for prediction of retention time in gas chromatography - Part I (Theoretical).
abstract: An approach that is commonly used for calculating the retention time of a compound in GC departs from the thermodynamic properties ΔH, ΔS and ΔCp of phase change (from mobile to stationary). Such properties can be estimated by using experimental retention time data, which results in a non-linear regression problem for non-isothermal temperature programs. As shown in this work, the surface of the objective function (approximation error criterion) on the basis of thermodynamic parameters can be divided into three clearly defined regions, and solely in one of them there is a possibility for the global optimum to be found. The main contribution of this study was the development of an algorithm that distinguishes the different regions of the error surface and its use in the robust initialization of the estimation of parameters ΔH, ΔS and ΔCp.
authors.affiliation: Laboratório de Controle de Processos, Departamento de Engenharia Química e de Alimentos, Centro Tecnológico, Universidade Federal de Santa Catarina (UFSC), P.O. Box: 476, Florianópolis, SC 88010-970, Brazil. Electronic address: carlos.claumann@prosgrad.ufsc.br.
authors.forename: Carlos Alberto
authors.initials: CA
authors.lastname: Claumann
authors.affiliation: Departamento de Informática e Estatística (INE), Centro Tecnológico, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC 88010-970, Brazil. Electronic address: azibetti@gmail.com.
authors.forename: André
authors.initials: A
authors.lastname: Wüst Zibetti
authors.affiliation: Laboratório de Controle de Processos, Departamento de Engenharia Química e de Alimentos, Centro Tecnológico, Universidade Federal de Santa Catarina (UFSC), P.O. Box: 476, Florianópolis, SC 88010-970, Brazil. Electronic address: ariovaldo.bolzan@ufsc.br.
authors.forename: Ariovaldo
authors.initials: A
authors.lastname: Bolzan
authors.affiliation: Laboratório de Controle de Processos, Departamento de Engenharia Química e de Alimentos, Centro Tecnológico, Universidade Federal de Santa Catarina (UFSC), P.O. Box: 476, Florianópolis, SC 88010-970, Brazil. Electronic address: ricardo.machado@ufsc.br.
authors.forename: Ricardo A F
authors.initials: RA
authors.lastname: Machado
authors.affiliation: Laboratório de neuroengenharia computacional, Departamento de Engenharia Química e de Alimentos, Centro Tecnológico, Universidade Federal de Santa Catarina (UFSC), P.O. Box: 476, Florianópolis, SC 88010-970, Brazil. Electronic address: leonel.t.pinto@ufsc.br.
authors.forename: Leonel Teixeira
authors.initials: LT
authors.lastname: Pinto
mesh_terms: D000465:Algorithms; D002849:Chromatography, Gas / Q000379:methods*; D013696:Temperature; D013816:Thermodynamics
keywords: Gas chromatography; Initialization method; Optimization; Parameter estimation; Retention time; Thermodynamic properties