Principle of nonlinear chemical fingerprint by using dissipative components in samples as well as calculation and evaluation of similarity

Abstract

Under the conditions of constant temperature and pressure, different influences of samples with different chemical components on the mechanism of nonlinear chemical reaction will cause different changes of the potential-time relationship curve of the nonlinear chemical reaction system. Using it as the character, and using the B-Z nonlinear chemical system to use acetone and substrates in samples as main dissipative substances qua an example, the principle of nonlinear chemical fingerprint has been researched and discussed in detail. At the same time, the general method for calculating the system similarity about nonlinear chemical fingerprint was also put forward, and similarities of nonlinear chemistry fingerprints of different batches of Guhan Yangshengjing and 18 sorts of other samples were calculated by Euclidean distance, correlation coefficient, included angle cosine and system similarity, at the same time, the various similarities were analyzed. The results showed that, both of correlation coefficient and included angle cosine are unable to be used as the criterion for quantitatively evaluating the similarity of nonlinear chemistry fingerprint; as non-parametric similarity, Euclidean distance can accurately reflect the feature differences in the fingerprints, but as parametric similarity, sometimes, Euclidean distance can not accurately reflect the relative extent of characteristic difference in the nonlinear chemical fingerprints; system similarity can most truthfully reflect the characteristic difference in the nonlinear chemical fingerprints, and is the best evaluating method among the four ones. Therefore, system similarity can be used to quantitatively calculate the similar extent between the nonlinear chemical fingerprints. An economical, simple and convenient, easy pushing and effective method for identifying and evaluating complicated samples has successfully been put forward.

Determining method, conditional factors, traits and applications of nonlinear chemical fingerprint by using dissipative components in samples

“…(5) Effect of temperature According to "Procedure" Section 2.2, the nonlinear chemical fingerprints of solid Kafu fruit drink with grape flavor (1.0000g) were determined at 27,30,35,37,40,45,47, 50 and 55 °C, respectively ( Figure 4). It is obvious from the figure that the fingerprint shape and the quantitative information are very sensitive to the temperature change.…”

“…The parallel determination of identical sample was carried out with the analytical instrument of nonlinear chemical fingerprint under the optimum conditions, and the results showed that the fingerprint was of very good reproducibility; because of the differences in the components and their contents of different sorts of samples, both of the indexes of the quantifiable information and intuitionistic shapes of the inductive curve, undulatory curve and period waves in the relevant fingerprint are partly or wholly different, that is, the differences in the internal components and their contents of different samples may be revealed by the nonlinear chemical fingerprint, so the fingerprint is of the qualitative functions to the sample and the relative quantitative functions to the total content of the components [38,45]. Therefore, the abundance of the quantifiable and intuitionistic information, namely the characteristic parameters and shapes of the nonlinear chemical fingerprint may be used to evaluate quality of the sample and identify its authenticity.…”

“…In fact, spectral or chromatographic fingerprints is just a part of the information in the relevant spectrum or chromatogram because they can be obtained generally only after the range of wavelength of spectrum or the relative retention of chromatogram is selected or intercepted. Contrary to the both, nonlinear chemical fingerprint can reflect the kinetic information in entire nonlinear chemical reaction because it need not select the range of the reaction time, and is really the full fingerprint with plenty of qualitative and quantitative information [38,45] (Figures 3, 7-10 and 13).…”

“…Firstly, the sample may correctly be identified and evaluated by directly using the shape, qualitative parameter and quantitative parameter in the nonlinear chemical fingerprint, because the fingerprint as the throng characterization of components in the sample has plenty of qualitative and quantitative information, very good characteristic (Figures 9, 10 and 13) and reproducibility (see Figures 2 and 5 ref. [45]). In general, the parallel determinations of a large number of samples and the pattern recognition of experimental data, etc are unnecessary in the identification and evaluation by nonlinear chemical fingerprint.…”

“…If the determining conditions are invariable, even through determinations by different operators, the uniform fingerprints of the same sort of samples with the same source may also be obtained due to the uniform chemical components and their uniform contents in the samples [45]. So the changes of the components and their contents or the change of quality of a product can be reflected by changes of shapes or qualitative and quantitative parameters of the fingerprints.…”