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Cycles Superposition

The case spectra made of superposition of cycles is the most frequent in real life and can be analyzed by the Fourier transform, as seen in Sect. 8.5. Some key examples from the simplest to the most complex superposition are offered in Fig. 8.43. The time history (a) of Fig. 8.43 is the simplest case made of two sine waves of slightiy different amplitude and closely-spaced frequencies. Combined the two waves show the characteristic beat frequency pattern. It is a narrow-band process because in the time period T it can be counted 5 zero upcrossing and 5 peaks with an irregularity factor y — 1, see Eq. (8.2). Case (b) of Fig. 8.43 refers to a high frequency load cycle of amplitude Sai and angular frequency coif superimposed to a low frequency cycle of amplitude Sa2 and angular frequency u 2t, with Sa2 and CO2 C coj or, case (c) of Fig. 8.43, with Sai Sa2- It can be written [Pg.454]


There is an additional pressure drop across the cake, developed by electroosmosis, which leads to increased flow rates through the cake and further dewatering at the end of the filtration cycle. The filtration theory proposed for electrofiltration assumes the simple superposition of electroosmotic pressure on the hydraulic pressure drop. [Pg.390]

As approaches the crack can also propagate by hydrogen embrittlement processes during the higher load parts of the stress cycle. This forms the basis of various models which have been developed to describe corrosion fatigue, probably the best-known of which are the superposition models due to Wei"". In its most recent version this model takes the form ... [Pg.1254]

Sp = 1. Thus N(C) is the sum of the coefficients in the expression C. For a cycle index A we have, by definition, N(A) = 1, From what has been stated above, it follows that N(A B) will be the num- ber of superpositions of the two graphs. Moreover the "product" A B can be extended, by associativity, to any number of cycle indexes, and will again be the cycle index sum for the superpositions of many graphs. Hence if A- denotes, for brevity, the cycle index of the automorphism group of Tj -- our previous Z(C.) --then the number of superposed graphs is given by... [Pg.112]

The distinct superpositions are shown in Figure 6 together with their automorphism groups, from which we can verify the assertions made above about the sum of their cycle indexes. For... [Pg.112]

The superposition of the vertical biological cycle on the horizontal ocean circulation pattern leads to three general features in the distribution of the elements involved in this cycle. [Pg.268]

There are two important consequences of this superposition of biological cycling on the ocean circulation pattern that show up in the sediments. [Pg.269]

The NMR experiments were performed using the quadrupolar echo pulse sequence 7i/2x—Ti—7i/2y—T2—acquisition with phase-cycling and quadrature detection. A Bruker MSL 400 spectrometer was used for the high pressure studies operating at a resonance frequency of 61.4 MHz. In the liquid-crystalline phase, perdeuterated lipids display NMR spectra, which are superpositions of axially symmetric quadrupolar powder patterns of all C-D bonds.From the sharp edges, the quadrupolar splittings... [Pg.169]

In our experience, the principal challenges in the application of ATR IR spectroscopy for investigations of functioning solid catalysts are associated with the sensitivity of the measurement and the complexity of the samples. The former is an issue common to most surface spectroscopies. The latter has to do with the simultaneous presence of many species at a catalytic solid-liquid interface these species include dissolved reactants, adsorbed intermediates, spectators, and products. The spectra are a superposition of the spectra of the individual species. The question of whether a species is a spectator or instead involved in the catalytic cycle is not easily answered and represents a challenge for in situ spectroscopy in general. Thus, there is a need for specialized techniques to be used in combination with ATR spectroscopy to enhance sensitivity and introduce selectivity. [Pg.259]

In the second place, the spectrum of 3 Lyr is a very peculiar one, characterized not only by photospheric absorption lines but also by emissions that are strong in H, and are also present in He, and by other features, which arise partly in the gaseous stream from the B8 II component and partly in the outer edges of the opaque disk that surrounds and hides the so far unobservable companion. As it has been shown by Batten and Sahade (1973), in the case of H a, and by Aylin et al. (1987), in the case of the resonance lines of C IV, Si IV and N V in the IUE ultraviolet range, the line profiles can be interpreted in terms of a superposition of two profiles, one of them a broad, relatively faint emission that shifts back and forth throughout the orbital cycle. The behavior of the radial velocities from this feature suggests that it shares roughly the expected orbital motion of the companion to the B8 II component and, therefore, that it may arise in the optically thick disk that surrounds it. [Pg.201]

In the general formulation the reactive processing model (Section 2.1), it was stressed that different phenomena occurring during a process cycle may be superimposed and that may be mutual influence between the various processes. Superposition of polymerization and crystallization is of particular importance, because it always occurs when a crystalline polymer is synthesized below its melting point. It is especially convenient to study this effect for anionic activated polymerization of e-caprol-... [Pg.58]

The reactive mix is injected or poured into a preheated mold, since a high temperature is necessary to accelerate the chemical reactions leading to formation of the polymeric product. Although an increase in temperature shortens the process cycle, it is important to remember that superposition of heat from an external source and the exothermal effect of the chemical reactions can result in undesirable temperature increase in an article, leading to thermal runaway and decomposition of the polymer. [Pg.131]

Figure 5.11 Charge density after the XUV-pump pulse, at small (top row) and large (bottom row) radii. At each breathing cycle, the metastable wave packet, formed by a coherent superposition of doubly excited states, ejects a burst of electrons. The peak of the free electron density originating close to the nucleus results in a wave front, which propagates outward at almost constant speed, up to very large distances. Figure 5.11 Charge density after the XUV-pump pulse, at small (top row) and large (bottom row) radii. At each breathing cycle, the metastable wave packet, formed by a coherent superposition of doubly excited states, ejects a burst of electrons. The peak of the free electron density originating close to the nucleus results in a wave front, which propagates outward at almost constant speed, up to very large distances.
In the third place the question arises how the time and frequency scales have to be joined together to connect results of creep or relaxation to those of vibration experiments. It will be clear that here the superposition principle can be applied, since with vibrations the imposed stress (or the strain) varies continuously. Using this principle and using the complex E modulus (or the complex compliance D), it can be shown that, with a few simplifications, t and 1/ffl can be considered as the same parameter, while co = 2nv (v is the frequency in cycles/sec). It has been... [Pg.113]

Externally driven limit cycles can exhibit a great variety of behaviour. Quite generally, one gets a nonlinear superposition of an internal nonlinear oscillation with an external oscillatory perturbation. Details of the resulting behaviour (including sub- and superharmonic oscillations, entrainment, quenching...) depend on both, the frequency and intensity of the applied fields and on the internal nonlinear kinetics of the considered system. [Pg.221]

The commercial DLC must also fulfill its functional task in a wide range of conditions. For example, specifications define the superposition of the following working conditions a temperature domain defined between -40°C and 70°C, combined with a voltage cycling between 1.35 and 2.7 V, 50 G mechanical shocks, and a current intensity distribution between -0.2 and +0.2 A/F. [Pg.430]

The procedure that we propose to enhance the concentration of a particulap enantiomer when starting with a racemic mixture, that is, to purify the mixture) is as follows [259], The mixture of statistical (racemic) mixture of L and irradiated with a specific sequence of three coherent laser pulses, as described below. These pulses excite a coherent superposition of symmetric and antisymmetric vibrational states of G. After each pulse the excited system is allowed to relax bg t to the ground electronic state by spontaneous emission or by any other nonradiativ process. By allowing the system to go through many irradiation and relaxatio cycles, we show below that the concentration of the selected enantiomer L or can be enhanced, depending on tire laser characteristics. We call this scenario lat distillation of chiral enantiomers. [Pg.176]


See other pages where Cycles Superposition is mentioned: [Pg.454]    [Pg.454]    [Pg.108]    [Pg.130]    [Pg.215]    [Pg.192]    [Pg.1308]    [Pg.225]    [Pg.118]    [Pg.42]    [Pg.210]    [Pg.230]    [Pg.204]    [Pg.455]    [Pg.408]    [Pg.42]    [Pg.212]    [Pg.234]    [Pg.61]    [Pg.261]    [Pg.430]    [Pg.33]    [Pg.30]    [Pg.85]    [Pg.92]    [Pg.443]    [Pg.54]    [Pg.479]    [Pg.52]    [Pg.147]    [Pg.195]    [Pg.413]   


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