Pulsating spot

Additional evidence was obtained from Auger surface analysis of the Pt-sapphire specimens. Peak-to-peak heights of the lead line at 94 eV were taken from six spots on the Pt-covered area and from six spots on the adjoining sapphire area after a 24-hr exposure to pulsator exhaust. There was, after correction of the 94-eV line for backscattered electrons, more lead on the Pt-covered area in five out of six comparisons. On the average there was a 50% higher lead content on the Pt-covered areas. At lower lead exposures the differences are difficult to discern, since the accumulation of the ubiquitous particulate lead is not expected to vary from one kind of surface to another. Such behavior is essentially in accord with the findings of Williams and Baron (95). At present, however, we still must consider the preferential association of lead with Pt or Pd only as eminently plausible but in need of further, still more direct confirmation. 

A 47-year-old woman complained of recurrent headaches. She described the pain as unilateral, located in the temple, and having a rhythmic or pulsating quality. The headaches arise spontaneously— often awakening her in the middle of the night. The headaches are accompanied by nausea, abdominal pain, and spots before the eyes. 

We find that the pulsating planar solution is stable for small R, but becomes unstable to nonplanar perturbations for larger values of R. Our results show that the transition from pulsating planar, i.e., one dimensional behavior, to spot behavior is a jump transition, i.e., the spots enter with finite amplitude as R increases, consistent with the phenomenological description in [2]. This is not surprising since instability of the uniformly propagating solution is also expected to lead to instability of spinning solutions which differ infinitesimally from it. 

Many cells of the tissue have been injured whereby the gum arabic has wholly or largely left them. Only three cells have not been injured and have accumulated toluidine blue to a maximum extent, a Initial state the toluidine blue arabinate coacervate is on the wall. The white streaks and spots in these cells are places where because of folds in the celloidin membrane the coacervate on the wall is very thin and thereby transparent, b and c successive stages of the change in the wetting caused by treatment with 5 m. eq. per I NaCl. Pulsating vacuoles are formed in the coacervate drops in c. d In a later stage and after application of a direct current field (anode on the left, cathode on the right) see text. 

Fronts do not have to propagate as planar fronts. Analogous to oscillating reactions, a steady state can lose its stabihty as a parameter is varied and exhibit periodic behavior, either as pulsations or spin modes in which a hot spot propagates around the reactor as the front propagates, leaving a helical pattern (Figure 4.15). This mode was first observed in SHS [89]. 

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