title: Solution identification and quantitative analysis of fiber-capacitive drop analyzer based on multivariate statistical methods.
abstract: A fiber-capacitive drop analyzer is an instrument which monitors a growing droplet to produce a capacitive opto-tensiotrace (COT). Each COT is an integration of fiber light intensity signals and capacitance signals and can reflect the unique physicochemical property of a liquid. In this study, we propose a solution analytical and concentration quantitative method based on multivariate statistical methods. Eight characteristic values are extracted from each COT. A series of COT characteristic values of training solutions at different concentrations compose a data library of this kind of solution. A two-stage linear discriminant analysis is applied to analyze different solution libraries and establish discriminant functions. Test solutions can be discriminated by these functions. After determining the variety of test solutions, Spearman correlation test and principal components analysis are used to filter and reduce dimensions of eight characteristic values, producing a new representative parameter. A cubic spline interpolation function is built between the parameters and concentrations, based on which we can calculate the concentration of the test solution. Methanol, ethanol, n-propanol, and saline solutions are taken as experimental subjects in this paper. For each solution, nine or ten different concentrations are chosen to be the standard library, and the other two concentrations compose the test group. By using the methods mentioned above, all eight test solutions are correctly identified and the average relative error of quantitative analysis is 1.11%. The method proposed is feasible which enlarges the applicable scope of recognizing liquids based on the COT and improves the concentration quantitative precision, as well.
authors.affiliation: State Key Laboratory of Precision Measuring Technology and Instruments, College of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Zhe
authors.identifier: 0000000184657568
authors.initials: Z
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Precision Measuring Technology and Instruments, College of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Zurong
authors.initials: Z
authors.lastname: Qiu
authors.affiliation: State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing 100084, China.
authors.forename: Xinming
authors.initials: X
authors.lastname: Huo
authors.affiliation: State Key Laboratory of Precision Measuring Technology and Instruments, College of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Yuming
authors.initials: Y
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Precision Measuring Technology and Instruments, College of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
authors.forename: Xinghua
authors.initials: X
authors.lastname: Li