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Dynamics resonance operator

Dynamic regime (T When the period of the oscillation is of the order of the system s characteristic response lime, the system is in intermediate or dynamic periodic operation. The transient behavior of the system has to be determined to predict the effects of periodic operation. Dynamic reactor operation may result in considerably higher performance if resonance phenomena are involved, and therefore this range of operation is of particular interest for optimization of the reactor. [Pg.225]

As we have stated, the Floquet Hamiltonian (113) has no terms that are resonant if we take small enough e, and the iteration of the KAM procedure converges. However, if we take e large enough, we encounter new resonances that are not present at zero or small fields that is, they are not related to degeneracies of the unperturbed eigenvalues of Kq that lead to the zero-field resonances we have discussed in the previous subsection. These new resonances are related to degeneracies of the new effective unperturbed operator K 0(e), which appear at some specific finite values of e. These are the dynamical resonances. [Pg.177]

The Use of Expectation Values of Resonance Operators to Visualize Dynamic Processes. 697... [Pg.622]

The fractional dynamical importance of the /c- th resonance operator relative to all of the coupling terms in Hres is... [Pg.649]

As a result, the early time dynamics of acetylene could be affected by numerous near resonant anharmonic interactions. Nine such anharmonic resonances are well characterized and known to be dynamically relevant. One needs a framework to relate the Fourier amplitudes and phases of the time-dependence of any observable quantity to the expectation values of each of the resonance operators in order to establish the relative importance of each of the resonances. [Pg.698]

Modification of an AFM to operate in a dynamic mode aids the study of soft biological materials [58]. Here a stiff cantilever is oscillated near its resonant frequency with an amplitude of about 0.5 nm forces are detected as a shift to a new frequency... [Pg.297]

Another resonant frequency instmment is the TA Instmments dynamic mechanical analy2er (DMA). A bar-like specimen is clamped between two pivoted arms and sinusoidally oscillated at its resonant frequency with an ampHtude selected by the operator. An amount of energy equal to that dissipated by the specimen is added on each cycle to maintain a constant ampHtude. The flexural modulus, E is calculated from the resonant frequency, and the makeup energy represents a damping function, which can be related to the loss modulus, E". A newer version of this instmment, the TA Instmments 983 DMA, can also make measurements at fixed frequencies as weU as creep and stress—relaxation measurements. [Pg.199]

The historical development and elementary operating principles of lasers are briefly summarized. An overview of the characteristics and capabilities of various lasers is provided. Selected applications of lasers to spectroscopic and dynamical problems in chemistry, as well as the role of lasers as effectors of chemical reactivity, are discussed. Studies from these laboratories concerning time-resolved resonance Raman spectroscopy of electronically excited states of metal polypyridine complexes are presented, exemplifying applications of modern laser techniques to problems in inorganic chemistry. [Pg.454]

I now consider statement 3 How should an extension of dynamics be understood In the MPC theory the problem does not exist For the intrinsically stochastic systems there is no need for modifying the laws of dynamics. As for the LPS theory, one notes the presence of two essentially new concepts. The introduction of non-Hilbert functional spaces only concerns the definition of the states of the dynamical system, and not at all the law governing their evolution. It is an important precision introduced in statistical mechanics. The extension of dynamics thus only appears in the operation of regularization of the resonances. This step is also the one that is most difficult to justify rigorously it is related to the (practical) necessity to use perturbation calculus (see Appendix). [Pg.23]

When applied to spatially extended dynamical systems, the PoUicott-Ruelle resonances give the dispersion relations of the hydrodynamic and kinetic modes of relaxation toward the equilibrium state. This can be illustrated in models of deterministic diffusion such as the multibaker map, the hard-disk Lorentz gas, or the Yukawa-potential Lorentz gas [1, 23]. These systems are spatially periodic. Their time evolution Frobenius-Perron operator... [Pg.100]

The generalization to the control of the dynamics of a molecule with n electronic states is straightforward. For the purpose of deducing the control conditions we will examine the extreme case in which every possible pair of these electronic states is connected via the radiation field and a nonzero transition dipole moment. If the molecule is coupled to a radiation field that is a superposition of individual fields, each of which is resonant with a dipole allowed transition between two surfaces, the density operator of the system can be represented in the form... [Pg.243]

Before considering particular test methods, it is useful to survey the principles and terms used in dynamic testing. There are basically two classes of dynamic motion, free vibration in which the test piece is set into oscillation and the amplitude allowed to decay due to damping in the system, and forced vibration in which the oscillation is maintained by external means. These are illustrated in Figure 9.1 together with a subdivision of forced vibration in which the test piece is subjected to a series of half-cycles. The two classes could be sub-divided in a number of ways, for example forced vibration machines may operate at resonance or away from resonance. Wave propagation (e.g. ultrasonics) is a form of forced vibration method and rebound resilience is a simple unforced method consisting of one half-cycle. The most common type of free vibration apparatus is the torsion pendulum. [Pg.173]


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Resonance dynamics

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