Relative peak area

This is equal to the height of step of the integration trace. 

The number of peaks in a regularly split signal (e.g., a regularly spaced triplet, quartet etc., ) or other recognisable splittings (e.g., doublet of doublets etc.,), should be noted carefully. 

Therefore, multiplicity and the relative peak heights in a multiplet provide an useful additional check on the relative number of protons obtained from the integration of peak areas. 

coupling 1 Ha to another Hb may give rise to a doublet or a triplet or a doublet-of-doublet as shown below  

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Table 10.1 Compounds trapped by headspace SPME from different resins, gum resins and archaeological samples, presented by Increasing retention indices, with the corresponding relative peak areas (%) for each substance... 

Components are presented by increasing retention indices, with their corresponding relative peak area (%). Values in bold correspond to compounds in high level or characteristic of an... 

Figure 6.58 presents results obtained from these evaluations. Average peak areas obtained after FIA analysis employing an Agilent 1100 (API-ES) MS are shown. When relative peak area values (peak area due to analyte and internal standard) were used for reproducibility evaluation, percentage CV values ranged from 2.7 to 4.0% for the two lowest concentrations analyzed. 

Table 5.3 Relative peak areas in Mossbauer quadrupole doublets as a function of the angle between the radiation and the electric field gradient. 

Table 5.4 Relative peak areas in magnetically split Mossbauer spectra as a function of the angle

In total, 185 substances were found in the wing-sac liquid of male S. bilineata from a Costa Rican population. For a more detailed analysis the relative peak area of thirteen focus compounds was compared (Table 14.1). Of these nine were male-specific substances (indole, indol-3-carboxaldehyde, indole-3-carboxylic acid, 2-aminoacetophenon, anthranilic acid, SHJOH-dipyrrolofl -aT -dJpyrazine-5,10-dione (pyrocoll), indolo[2,l-b]quinazoline-6,12-dione (tryptanthrin), 2,6,10-trimethyl-3-oxo-6,10-dodecadienolide, and a compound C15H24O2 of unknown structure), three were fatty acids (tetradecanoic acid, hexadecanoic acid, and octadecanoic acid), and one a steroid (cholesterol). On average, the cumulative peak area of these substances made up 62.5 20.7% of the whole chromatogram area. 

Fig. 6.3.2. (— )-LC-ESI-MS extracted ion chromatogram of C7-SPC (mlz 285) in samples from (A) Rio Macacu, Brazil, (B) river Rhine, Germany, and (C) Baia de Guanabara, Brazil. Values in parentheses indicate relative peak area (a + b + c = 100%) (from...

The CE method was validated in terms of accuracy, precision, linearity, range, limit of detection, limit of quantitation, specificity, system suitability, and robustness. Improved reproducibility of the CZE method was obtained using area normalization to determine the purity and levels of potential impurities and degradation products of IB-367 drug substance. The internal standard compensated mainly for injection variability. Through the use of the internal standard, selected for its close mobility to IB-367, the method achieved reproducibility in relative migration time of 0.13% relative standard deviation (RSD), and relative peak area of 2.75% RSD. 

For example, to determine the empirical formula of di-n-octylphthalate, the daughter spectrum of the containing molecular ion (392) was obtained (Figure 7). The relative peak areas of adjacent peak pairs at m/z 149 and 150 is 2 1. This indicates that the M+1 ion is twice as likely to lose a atom as retain it. Thus the ratio of the number of carbon atoms lost to those retained is 2 1. Since the identified phthalate substructure contains 8 carbons, the unknown compound (di-n-octylphthalate) must contain 24 carbon atoms. These data, along with the molecular weight of 390 as determined from the conventional Cl mass spectrum of the unknown was fed into the empirical formula generator and the output was one empirical formula C24H38O4. 

In Fig. 8 the vertical bars in the scheme on top of the diagram symbolize the respective isolated starting peak of the chromatogram below. The products of heat sterilizations are found on the horizontal lines below the chromatogram. The length of the bars indicates the relative peak areas obtained after sterilization. 

Comparison of the relative peak areas of the model compounds with those of iotrolan shows a striking similarity (Table 4). 

Schaefer and Natusch have shown that for many synthetic high polymers in solution the NOE factors and relaxation times of carbon atoms in or near the main chains eire similcir (.2. In such cases the relative peak areas in the spectra obtained by the noise-decoupled and fast pulsing technique can be used as a good approximation for quantitative microstructure euialysis. However for our investigation of the polymerization of cyclic ethers we are frequently interested in the quantitative measurements of monomers and oligomers as well as the concentrations of the continuously growing polymeric species. Therefore, the assumption of Schaefer and Natusch is not applicable. 

Next the time to reach the maximum signal and the relative peak area were determined as a function of the duration of the shutter opening (Figure 6). Relative peak area is almost constant after 1 s, whereas the time to reach the maximum amplitude becomes constant beyond 6 s. These findings are consistent with the presence of barriers to heat transfer in the DSC itself and between sample pan and the thermistor, which delay the transfer of the heat rather than changing the total amount of heat detected. 

A highly versatile method for enantiomer analysis is based on the direct separation of enantiomeric mixtures on nonraceinic chiral stationary phases by gas chromatography (GC)6 123-12s. When a linearly responding achiral detection system is employed, comparison of the relative peak areas provides a precise measurement of the enantiomeric ratio from which the enantiomeric purity ee can be calculated. The enantiomeric ratio measured is independent of the enantiomeric purity of the chiral stationary phase. A low enantiomeric purity of the resolving agent, however, results in small separation factors a, while a racemic auxiliary will obviously not be able to distinguish enantiomers. 

Figure 18-19 Laser spectroscopy of water vapor showing individual rotational transitions of H2I60, H2170, and H2,8O.The upper trace is from a standard water sample and the lower trace is from an unknown. Relative peak areas In the two spectra provide isotope ratios to an accuracy of 0.1 %. [E. R. Th. Kerstel, R. van Trlgt,...

A. (a) When a solution containing 234 mg of butanol (FM 74.12) and 312 mg of hexanol (FM 102.17) in 10.0 mL was separated by gas chromatography, the relative peak areas were butanokhexanol = 1.00 1.45. Considering butanol to be the internal standard, find the response factor for hexanol. 

Trifluoroacetyl derivatives of amines were resolved on trifluoro-acetylated-L-valyl-L-valine isopropyl ester coated in capillary columns. Better efficiency was obtained when a ureide, which was formed by the condensation of phosgene with L-Valine isopropyl ester, was coated on glass capillaries of about 70 meters in length and 0.25 mm i.d. Purity of the reagent (column coating) will affect resolution but not the relative peak areas. 

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