Width at half height

The full width at half height of these Lorentzian peaks is 2/x. One says that the individual peaks have been pressure or eollisionally broadened. 

Narrow transitions (small a) yield large peak voltages and narrow pulse shapes (PIF q). The width at half height is given by equation 4 where... 

The peak width at half height (wq.s) is the distance between each side of a peak, measured at half the peak height. The peak width measured at half height has no significance with respect to chromatography theory. 

ATBN - amine terminated nitrile rubber X - Flory Huggins interaction parameter CPE - carboxylated polyethylene d - width at half height of the copolymer profile given by Kuhn statistical segment length DMAE - dimethyl amino ethanol r - interfacial tension reduction d - particle size reduction DSC - differential scanning calorimetry EMA - ethylene methyl acrylate copolymer ENR - epoxidized natural rubber EOR - ethylene olefin rubber EPDM - ethylene propylene diene monomer EPM - ethylene propylene monomer rubber EPR - ethylene propylene rubber EPR-g-SA - succinic anhydride grafted ethylene propylene rubber... 

Nuclear Magnetic Resonance. The sampie is dissolved in anhyd (0.02% w) dimethylformamide and the NH4 peak width at half-height measured at 7.38t and compared with a graph prepd from samples of AP contg known amts of w. 

In these equations A and np are the molar fractions of A and P (8 v) = v - vp is the difference between the resonance frequencies of the nuclei in positions A and P, usually determined from the low-temperature limit A is the full-width at half height in the absence of exchange (r - °°) and v is the variable radio frequency of the NMR experiment. 

In the fast exchange limit ft2 A2, a Lorentzian at the centre d>, is observed with full width at half height 2/T + A2/Q. In the ultrafast exchange limit discussed in the previous section, A2/fi 2/T, the line shape becomes independent of the exchange... 

The quasi-classical description of the Q-branch becomes valid as soon as its rotational structure is washed out. There is no doubt that at this point its contour is close to a static one, and, consequently, asymmetric to a large extent. It is also established [136] that after narrowing of the contour its shape in the liquid is Lorentzian even in the far wings where the intensity is four orders less than in the centre (see Fig. 3.3). In this case it is more convenient to compare observed contours with calculated ones by their characteristic parameters. These are the half width at half height Aa)i/2 and the shift of the spectrum maximum ftW—< > = 5a>+A, which is usually assumed to be a sum of the rotational shift 5larger scale A determined by vibrational dephasing. 

The half-width (at half-height) and the shift of any vibrational-rotational line in the resolved spectrum is determined by the real and imaginary parts of the related diagonal element TFor linear molecules the blocks of the impact operator at k = 0,2 correspond to Raman scattering and that at k = 1 to IR absorption. The off-diagonal elements in each block T K, perform interference between correspond-... 

Figure 2.4 Illustration of HPLC parameters to, retention time of a non-retained component fA and fe, retention times of analytes A and B w, width of peak at base wq.5, width at half-height.

Figure 7.4 Change In peak width at half height as a function of nigration distance for a typical test nixture on a high perfomance TLC plate. The values for b, and bf are calculated by extrapolation using linear regression.

K Wn Capacity factor Peak width at half height t /to ... 

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