Resonance phenomenon

Materials are also classified according to a particular phenomenon being considered. AppHcations exploiting off-resonance optical nonlinearities include electrooptic modulation, frequency generation, optical parametric oscillation, and optical self-focusing. AppHcations exploiting resonant optical nonlinearities include sensor protection and optical limiting, optical memory appHcations, etc. Because different appHcations have different transparency requirements, distinction between resonant and off-resonance phenomena are thus appHcation specific and somewhat arbitrary. 

When discussing magnetic resonance phenomena, it is conventional to proceed along the lines of standard perturbation theory. If the field-free Hamiltonian is Hq then we write... 

When both reactants have comparable ionization potentials, there is a close relationship between the H2 and H2 transfer reactions. For instance, a low efficiency of the H. transfer reaction from the alkane to a neutral olefin molecule (at least in the case of cyclohexane) is paralleled by a low efficiency of the corresponding H2 transfer process. Such a relationship can be accounted for by resonance phenomena. Unfortunately, not enough information is available on those systems where the... 

In addition and importantly, even in non-active junctions, when the electrode Fermi level matches the molecular bridge energy levels, resonance phenomena can generate electrical behaviours similar to those of conventional electronic devices, such as rectification [86-89] and negative differential resistance (NDR) [90, 91]. 

The significance of the coupling of micro- and macrorelaxations for resonance phenomena observed in catalytic systems under forced periodic operation (cycling) (15) implies that the wave-front analysis of transients of this kind can eventually suggest a more effective strategy in seeking the optimal conversion and selectivity. Finally the existence of certain surface structures and complexes could be established, if the transients of the surface intermediates will be followed e.g. by infrared spectroscopy (see e.g. (16, 17)). 

The physical picture which I think is undoubtedly correct is that the interaction forces [in metals] are much as in diatomic molecules, determined by resonance phenomena, and I want to fit that in with the problem of many atoms. 71... 

As discussed in Section II,A,2, the motion of nuclei has a very pronounced influence on the nuclear magnetic resonance phenomena. The local fields experienced by the nuclei, after a certain frequency of motion has been exceeded, decrease as the rate of motion increases. 

According to several studies [12,13,19,96], the two principal features of stochastic resonance phenomena are that the signal and/or the signal-to-noise ratio R... 

Positrons exhibit resonance phenomena in collisions with some atomic and molecular targets and, as with electrons, an infinite series of resonances is expected to be associated with each degenerate excitation threshold (Mittleman, 1966). For electrons, such thresholds can only arise with hydrogenic targets, but for positrons there are also degenerate thresholds in the excitation of positronium. Several of these resonances have been identified theoretically for a few simple target systems, but they are too narrow to be observed experimentally with the presently available energy resolution of positron beams. 

We met at most of the Conferences AMPERE, devoted to magnetic resonance phenomena, which purposely took place consecutively one time in the west and next time in the east of Europe. I had the pleasure to invite Isaac to the Research IBM laboratory in Riischlikon, my permanent work place and our home in Hedingen, and later also to the IBM TJ. Watson Research Center in Yorktown Heights, New York, where I was active for two years at the end of the seventies. 

Despite the many theoretical predictions of inelastic resonances (mainly observed in calculations with reduced dimensionality Manz 1989, for example) we do not know of an unambiguous experimental observation of resonances in atom-molecule or molecule-molecule gas-phase collisions. In contrast to full atom-molecule collisions pronounced resonance-like structures are actually rather common features in bound-continuum absorption spectra (Robin 1974, 1975, 1985 Okabe 1978 Fano and Rao 1986). In fact, all sharp structures in UV absorption spectra can be considered as resonances and therefore photodissociation provides ideal opportunities to investigate resonance phenomena, such as the lifetime, the decay mechanism, and the final state distributions of the fragments, on a very detailed basis. 

Halberstadt, N., Beswick, J.A., and Schinke, R. (1991). Rotational distributions in the vibrational predissociation of weakly bound complexes Quasi-classical golden rule treatment, in Half Collision Resonance Phenomena in Molecules Experimental and Theoretical Approaches, ed. M. Garcia-Sucre, G. Raseev, and S.C. Ross (American Institute of Physics, New York). 

Imaging techniques that utilize low-energy resonant phenomena (electronic, vibrational, or nuclear) to probe the structure and dynamics of molecules, molecular complexes, or higher-order chemical systems differ from approaches... 

One approach being pursued by Japanese investigators makes use of the electron cyclotron resonance phenomena discussed earlier.24 In this case, a... 

In addition, these chromophores are very delicate molecules from an energy state perspective and should not be subject to detergents and other reactants such as sodium based complex salts. Although, it is possible (and actually easy) to return the chromophores of vision to the liquid crystalline state after extraction and purification, it is not easy to prevent conversion of the chromophores into their chromogens or similar retinoids. These decomposition products do not exhibit the resonance phenomena (and resulting spectral characteristics) no matter what state of matter they are in. 

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