Dynamic Interference SRI

An attempt to achieve high-resolution signals in the solid state might be hampered when incoherent frequencies of slow motions interfere with 

Instead of the frequency-dispersion so far discussed, the experimental SRI data can be visualized as temperature or pH dispersions by a plot 

The suppression temperatures Tg s, at which the peak intensity is most suppressed as shown by the arrows in the temperature-dispersion curves for PMEA hydrogel, turn out to be —10 ° C (a), —40 ° C (b), and —50 ° C (d), for the carbons of the backbone, terminal CH3 and CH2 of side-chain, respectively. This parameter can be considered to indicate at which temperature carbons located at the specific polymer chain undergo fluctuation motions with a frequency of f lO Hz. Similar temperature-dispersion (Fig. l.lOB) is noted for the A18 Cp signal (at 15.7 ppm) of CPMAS NMR spectra of [3- C]Ala -A(6—42) fragment of bR in DMPC bilayer (Fig. 1.1 OA) [118], The suppression temperature Ts for this peak turns out to be 30 °C, just above the gel-to-Hquid crystalline phase transition which is conveniently monitored by relative peak-intensities of the fatty acyl chain at 

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