Chromatographic peak fitting

However, the T-distribution permits an extension of the plate theory, which is also usable in case of asymmetric peaks. The chromatogram (1 component) is considered to be the result of a pure time delay and a T-distribution response. The procedure implies the fitting of a function f(t) given in Eq. (15) to the chromatographic peak. The asymmetry of the peak determines the new plate number n, decreasing with increasing asymmetry. 

Perform peak fits for the liquid chromatographic separation of proteins as shown below ... 

In practice, diere are an infinite, or at least very large, number of statistically identical models diat can be obtained from a system. If I know that a chromatographic peak consists of two components, I can come up widi any number of ways of fitting the chromatogram all with identical least squares fits to die data. In the absence of further information, a smoother solution is preferable and most definitions of entropy will pick such an answer. 

Figure 4. Fluorescence peak area quenching (Xcxciution 332 nm, X nission = 442 nm) of SFA chromatographic peak 1 (a), peak 2 (O), and peak 3 ( ), and best-fit quenching curves for peak 1 (-), peak 2 (—) and peak 3 (...).

According to the extensive review by Marco and Bombi [7], almost 100 dedicated empirical or semiempirical formulae have been proposed for the chromatographic peak shapes. Some of them may reasonably well fit experimental data, even when physicochemical rationale for them is lacking. 

Fig. 4 Overlapped chromatographic peaks resolved by the conventional curve-fitting method. The dotted lines represent the Gaussian functions from curve-fitting treatment.

Meaningful chromatographic data can be extracted from asymmetric peaks by digital integration or curve fitting routines applied to the chromatographic peak profile. The statistical moments of a chromatographic peak in units of time are defined by Eq. (1.37) to (1.39) [153,184,187,188]... 

Several authors have described their experience in resolving S5mtheti-cally overlapping and real gas chromatographic peaks by the curve-fitting procedure. 

Fludized bed chromatography (FBC) indirectly measures the intraparticle diffusion under liquid. Breakthrough curves from the chromatograph from fixed beds of either ion-exchange resin or solids are fit to mathematical models in order to dednce snrface diffusion parameters from chromatographic peaks from pulse responses [98Kohl]. 

The atomizer is just a few cm long (Figure 168) and can be fitted into almost any commercial a.a.s. unit. Fast electronics are not necessary because the metal concentration is measured as a gas chromatographic peak which takes several seconds to evolve. 

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