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Peaks anomalous

Measurement of ionization potentials has shown that 2,4,6-triphenylpyrylium salts undergo a thermal reduction in the mass spectrometer giving the corresponding free radicals. Steric properties preclude dimerization (74OMS(9)80>. This type of reduction appears to be largely independent of the nature of the anion the bromide and iodide salts behave identically. However, in the case of the tetrafluoroborate salt, adduct formation between a cation and a fluoride ion gave a minor peak. Anomalous behaviour is displayed by the perchlorates the anion effects oxidation of the cation upon evaporation giving a base peak which corresponds to [M + 0-H]+. [Pg.620]

The difference electron density map following the last cycle of least squares refinement did not show evidence for a simple disorder model to explain the anomalously high B for the hydroxyl oxygen. Attempts to refine residual peaks with partial oxygen occupancies did not significantly improve the agreement index. [Pg.156]

The molecular collective behavior of surfactant molecules has been analyzed using the time courses of capillary wave frequency after injection of surfactant aqueous solution onto the liquid-liquid interface [5,8]. Typical power spectra for capillary waves excited at the water-nitrobenzene interface are shown in Fig. 3 (a) without CTAB (cetyltrimethy-lammonium bromide) molecules, and (b) 10 s after the injection of CTAB solution to the water phase [5]. The peak appearing around 10-13 kHz represents the beat frequency, i.e., the capillary wave frequency. The peak of the capillary wave frequency shifts from 12.5 to 10.0kHz on the injection of CTAB solution. This is due to the decrease in interfacial tension caused by the increased number density of surfactant molecules at the interface. Time courses of capillary wave frequency after the injection of different CTAB concentrations into the aqueous phase are reproduced in Fig. 4. An anomalous temporary decrease in capillary wave frequency is observed when the CTAB solution beyond the CMC (critical micelle concentration) was injected. The capillary wave frequency decreases rapidly on injection, and after attaining its minimum value, it increases... [Pg.243]

Perhaps the first clear observation of a reactive resonance in a collision experiment was recently made for the F + HD —> HF + D reaction.65-67 This reaction was one isotopomer of the F + H2 system studied in the landmark molecular beam experiments of Lee and co-workers in 1985.58 Unlike the F + H2 case, no anomalous forward peaking of the product states was reported, and results for F + HD were described as the most classical-like of the isotopes considered. Furthermore, a detailed quantum mechanical study68 of F + HD —> HF + D reaction on the accurate Stark-Werner (SW)-PES69 failed to locate resonance states. Therefore, it was surprising that the unmistakable resonance fingerprints emerged so clearly upon re-examination of this reaction. [Pg.60]

From this equation it can be seen that the depth of penetration depends on the angle of incidence of the infrared radiation, the refractive indices of the ATR element and the sample, and the wavelength of the radiation. As a consequence of lower penetration at higher wavenumber (shorter wavelength), bands are relatively weaker compared to a transmission spectrum, but surface specificity is higher. It has to be kept in mind that the refractive index of a medium may change in the vicinity of an absorption band. This is especially the case for strong bands for which this variation (anomalous dispersion) can distort the band shape and shift the peak maxima, but mathematical models can be applied that correct for this effect, and these are made available as software commands by some instrument manufacturers. [Pg.536]

Recently, a U.S.S.R.-Czechoslovokian research group have reported 14C data for dated wine samples from the Caucasus Mountains [27]. Their results are in fairly close agreement with our results for the time of overlapping data (figure 5). If the anomalous data for A.D. 1943 are omitted, the fifth order polynomial fit to the data yields a 5 per mil peak to trough amplitude with a phase lag of 4 years behind sunspot numbers. The amplitude... [Pg.240]

A second type of glaciochemical horizon, a long-term interval of anomalous concentrations rather than a sporadic peak, is demonstrated by Late Wisconsin dust. Greenland and Antarctic snow... [Pg.313]

The character of variations in the spatiotemporal field distribution in the guiding region depending on the sign of the GVD is shown in Fig.32. The most noticeable effect of dispersion manifests itself in the waveguide core, where in the case of normal GVD, the pulse continuously broadens simultaneously with the compression of its transverse distribution (Fig.32a). In the case of anomalous GVD, a so-called light bullet is formed (Fig.32b), which looks like a sharp increase in the intensity at the peak of the spatiotemporal distribution. [Pg.183]


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