Experimental Chromatograms

Figure 6. Effect of symmetrical axial dispersion correction on chromatogram heights experimental chromatogram (— —) chromatograms (Wn(y)) obtained...

Figure 7. Experimental chromatograms using different column codes ((-Code 25 (- - -) Code 27 (-. Code 28)...

F. Dondi, A. Betti, L. Pasti, M.C. Pietrogrande and A. Felinger, Fourier analysis of multicomponent chromatograms — application to experimental chromatograms. Anal. Chem., 65 (1993) 2209-2222. 

Davis, J.M., Giddings, J.C. (1985). Statistical method for estimation of number of components from single complex chromatograms application to experimental chromatograms. Anal. Chem. 57, 2178. 

Fig. 11. Experimental chromatogram of a separation of a solution containing PGMs and base metals using a mixed mode P-CAC system 1...

Vith the procedure outlined above, simple programs of programmable calculator (TI 59) and microprocessor (ZoO) for finding M(Vh) and <>o(%) were vrritten. The mean elution volume and total variance of the experimental chromatograms of well characterized polymer samples are first calculated according to... 

The uncertainty of the calculated spreading factor A(o q) depends upon the accuracy of the inhomogeneity index of the sample and that of the total variance of experimental chromatogram. It may be expressed as... 

If the experimental chromatogram is Gaussian, the spreading factor co ild be represented by... 

Figure 2 shows a fit of this function to the front half of an experimental chromatogram. 

Figure 2 A. Fit of a Gaussian shape function to the front half of an experimental chromatogram. B. Residual between the Gaussian and the experimental curve. (Reproduced with permission from Ref. 1. Copyright 1984, Elsevier.)...

Figure 5= Example 3 a) Experimental chromatogram, spreading function and comparison of present results with those in (U) b) Validation test for u(k).

A measure of the efficiency of the chromatography column is the height equivalent to a theoretical plate or plate height H [19]. The plate height for an experimental chromatogram is calculated from... 

Fig. 6. Experimental chromatograms (a) and shape of calibration dependences (b) for nonfunctional oligobutadicnes of different molecular weight in the exclusion, critical and adsorption separation modes.

In Figure 5.32 the optimum composition predicted from a combination of all three phase selection diagrams is a mixture that contains 10.4% methanol and 33.6% THF (x = 0.84). Eqn.(5.18b) then prescribes a shifted composition of 19.5% methanol and 28% THF (x = 0.7). Obviously, this composition does not fall within one of the (small) confidence regions, and therefore an experimental chromatogram is recorded at the shifted composition. This chromatogram is shown in figure 5.33 (chromatogram d). 

Interpretive methods will generally arrive at the global optimum after a limited number of experiments. However, (by definition) the recognition of the individual solutes is required in each experimental chromatogram. Also, the computational requirements are relatively high, especially if the simultaneous optimization of several parameters is considered. For example, (linear) ternary gradients (one parameter) will be much easier to optimize than quaternary gradients (two parameters). 

Statistical Method for Estimation of Number of Components from Single Complex Chromatograms Application to Experimental Chromatograms, J. M. Davis and J. C. Giddings, Anal. Chem., 57, 2178 (1985). 

There are programs for simulated chromatograms which are comparable to that obtained with experimental chromatograms.Other details concerning the strategy of optimization of the mobile phase can be found in Ref. [22]. 

Figure 19. Vanishing perturbation peaks in chiral LC at (a) weak and (b) moderate non-linear levels, (i) experimental chromatograms and (ii) simulated showing the sum and the individual concentrations of the isomers...

If the PP method is used in a multi-component case it should also be noted that the determined isotherm parameters could not be assigned to specific components without additional information, e.g., by comparing computer simulations with an experimental chromatogram where the peaks can be identified. 

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