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Frequency ratio

The analogous coupling between the antisyimnetric stretch and bend is forbidden in the H2O Hamiltonian because of syimnetry.) The 2 1 resonance is known as a Femii resonance after its introduction [ ] in molecular spectroscopy. The 2 1 resonance is often very prominent in spectra, especially between stretch and bend modes, which often have approximate 2 1 frequency ratios. The 2 1 couplmg leaves unchanged as a poly ad number the sum ... [Pg.70]

Figure Al.2.11. Resonant collective inodes of the 2 1 Fenni resonance system of a coupled stretch and bend with an approximate 2 1 frequency ratio. Shown is one end of a syimnetric triatomic such as H2O. The nomial stretch and bend modes are superseded by the horseshoe-shaped modes shown in (a) and (b). These two modes have different frequency, as further illustrated in figure Al.2.12. Figure Al.2.11. Resonant collective inodes of the 2 1 Fenni resonance system of a coupled stretch and bend with an approximate 2 1 frequency ratio. Shown is one end of a syimnetric triatomic such as H2O. The nomial stretch and bend modes are superseded by the horseshoe-shaped modes shown in (a) and (b). These two modes have different frequency, as further illustrated in figure Al.2.12.
Fig. 7. Transmissibihty as a function of frequency ratio for single-degree-of-freedom isolators with different degrees of internal damping. Fig. 7. Transmissibihty as a function of frequency ratio for single-degree-of-freedom isolators with different degrees of internal damping.
Figure 14.23 Amplification of vibrations versus frequency ratio... Figure 14.23 Amplification of vibrations versus frequency ratio...
Figure 5-13b. Phase angle as a function of the frequency ratio for various amounts of viscous damping. Figure 5-13b. Phase angle as a function of the frequency ratio for various amounts of viscous damping.
FolK = Deflection of the spring under load, (also called static deflection, Zst) a> = Forced frequency ft)jj = Natural frequency of the oscillation = Frequency ratio... [Pg.681]

Sufficiently irrational tori here means those tori whose frequency ratio uj /u>2 is such that... [Pg.192]

Frequency (cm-1) FWHM (cm-1) Relative strength Frequency (cm-1) FWHM (cm-1) Relative strength Frequency ratio... [Pg.171]

The vibrational characteristics of the 1560 cm-1 and 809 cm-1 bands are consistent with the donor-H configuration (Fig. 8) proposed by Johnson et al. (1986). The change in the vibrational frequency of the 1560 cm-1 band for the different donors is sufficient to show that the donor is involved in the complex. However, one would have expected the large change in the donor s mass and size when going from P to Sb to have had a greater effect on the vibrational frequency if the H were attached directly to the donor atom. Further evidence that the H is not attached to the donor directly comes from the frequency ratios, r, shown in Table II that are nearly constant for the different donors as would be expected if the H were attached to Si. [Pg.172]

Other PTMs may involve changes in the chemical nature of amino acids (e.g., citrullination or deimination). Because many of these modifications result in mass changes that are measurable by MS, they are amenable to detection by MS-based approaches. A number of emerging MS-based strategies allow the identification of PTMs. Several MS-based methods to determine the types and sites of protein phosphorylation and ubiquitination have been developed. Phosphorylation occurs mainly on serine, threonine, and tyrosine residues at a frequency ratio of 1800 200 1 in vertebrates.70 Although the phosphorylation of tyrosine residues occurs less frequently in the proteome, it has been extensively studied. [Pg.388]

Teller-Redllch rule phys chem For two isotopic molecules, the product of the frequency ratio values of all vibrations of a given symmetry type depends only on the geometrical structure of the molecule and the masses of the atoms, and not on the potential constants. tel-or red-lik, rul ... [Pg.368]

Figure I-2—Damping Factor Versus Frequency Ratio... Figure I-2—Damping Factor Versus Frequency Ratio...
For tetrahedral ions or molecules of the type XY , where X is a transition metal the vi(Fz)fvz(E) frequency ratio changes from a value of less than one to a value greater than one with the increasing mass ratio MxfMy. [Pg.86]

Probability can be defined as a limiting case of a frequency ratio, and from this view the various rules of probability can be derived. An alternative approach is an axiomatic one that states that there is a quantity called probability associated with events and that it possesses assigned properties. The former is largely the frequentist point of view, the axiomatic approach is shared by Bayesians and non-Bayesians alike. [Pg.74]

It should be noted that Eq. (7) allows of an explanation of the following experimental fact. It is known that the frequency ratio i AH/rAB of vibrations A - H and A—D in the hydrogen bond complexes is not exactly equal to /2 as it should be expected on the ground of the classical treatment. The reason for this is the presence of the term iejD) (hvJD) in Eq. (7i. Because of this fact the difference... [Pg.388]

To answer Prof. Marcus s question, we may therefore conclude that the natural motions of the system are the short-time periodic orbits. Those that arise from the symmetric-stretch bifurcations depend on the frequency ratio local modes in the 1 1 case, 7-shaped orbits at the 3 2 instability, horseshoes at the 2 1 resonances, and so on. [Pg.598]

In addition the study of the isotopes, like DO2. in the same potential energy surface may allow interesting comparisons on the appearance of chaos which is governed by the lowest overlapping resonances (which in turn depend on the vibrational frequency ratios, i.e. on the masses). [Pg.813]

Figure 8-6. The ratio of demixing parameters t ( AB 4= 0)/t °(LAB = 0), calculated with the Manning model, as a function of Curve parameter is the jump frequency ratio r= vA/vB. v, is obtained from D =g-A 2-vi-fi [M. Martin (1991)1. Figure 8-6. The ratio of demixing parameters t ( AB 4= 0)/t °(LAB = 0), calculated with the Manning model, as a function of Curve parameter is the jump frequency ratio r= vA/vB. v, is obtained from D =g-A 2-vi-fi [M. Martin (1991)1.
Following from eq. (1.8) and Fig. 2.35, the field/frequency ratio must not necessarily be stabilized for the nuclei to be observed (homonuclear lock). It can also be set using any other nucleus (heteronuclear lock). [Pg.70]

FIGURE 5 Subharmonic saddle-node bifurcations, (a). The subharmonic period 3 isola for the surface model (o/o0 = 1.4, o0 = 0.001). One coordinate of the fixed points of the third iterate of the stroboscopic map is plotted vs. the varying frequency ratio oi/eio. Six such points (S, N) exist simultaneously, three of them (N) lying on the stable node period 3 and three (S) on the saddle period 3. Notice the two triple turning point bifurcations at o>/o>o = 2.9965 and 3.0286. In (b) the PFM of these trajectories on the isola Is also plotted, (c) shows another saddle-node bifurcation occurring (for a>o = 3) as this time the forcing amplitude is increased to o/o0 = I.6SS. [Pg.239]

Cross sections of the a and fi Fermi surfaces and the y and 6 Fermi surfaces in the plane which includes the axis of rotation are shown in Figure 6.8. Each of the experimental Fermi surfaces has the axis of rotation about the [0001] axis. The dFIvA frequency values used to construct the Fermi surfaces are shown in Table 6.2. The values in parentheses in Table 6.2 are estimated frequencies that take into account the angular dependencies and the frequency ratios between the flux-grown crystal and the hole-doped crystal. The obtained Fermi surface dimensions are summarized in Table 6.3. [Pg.356]

For the transition state, of course, one of the 3 N — 6 vibrations is really a translation for the moment we single it out and write for its frequency ratio vj.nlvf.r>. When Equation A2.11 is substituted into Equation A2.10, the products of atomic masses will cancel, leaving Equation A2.12 ... [Pg.122]

When considering the bending of a beam and attempting to extract a modulus value one must make several assumptions, the most important being that the modulus in tension is the same as in compression, and is independent of strain (at least for the range of strain involved). The simple Bernoulli-Euler theory is usually used to interpret the data. When performing resonance tests it is particularly useful to find a set of resonances and compare the measured frequency ratios with the theoretical ones given in the previous chapter. [Pg.85]

Capturing vibrato through adjusting the carrier/modulation frequency ratio requires very precise control which is difficult to achieve. [Pg.224]

The stabilization of the field-frequency ratio, which is required for HDMR experiments in the INDOR mode, can be obtained by locking the NMR spectrometer field-frequency ratio to the resonance condition of a strong and sharp signal in the sample under investigation. (14) Additional stabilization can be achieved by locking together the main frequency of the spectrometer and master oscillator of the synthesizer. (15, 16) In this case, the drift in the frequency of the synthesizer is balanced by the change in the main frequency of the spectrometer. [Pg.294]

Generally speaking pollutant levels in fishes and other wildlife species have been decreasing in recent decades either in their average concentrations or in the detection frequencies (ratios of detectable sites among... [Pg.9]

KIEs to transition state structure, has a very broad maximum. Unfortunately, this means that these KIEs will not be useful in determining transition state structure in, S n2 reactions. The temperature-independent factor (imaginary frequency ratio) and the tunnelling contribution to the KIE ranged from 57.5 to 69.0% of the total KIE. [Pg.227]

The hysteresis property of any polyurethane is composed of two components, namely the spring and the viscous component. The viscous component is responsible for the absorption of the force and the conversion of the energy into heat. Any deflections must be within the limits where Hookes Law is obeyed (i.e., only 1 to 10%). The ratio between the forced and natural frequencies needs to be determined. The natural frequency is a function of the static deflection of the system. The damping ratio of the polyurethane also must be known. This can vary from 0.05 for highly resilient materials to 0.15 for low-resiliency materials. To obtain damping, the forced-to-natural damping frequency ratio must be greater than 1.4. [Pg.158]


See other pages where Frequency ratio is mentioned: [Pg.73]    [Pg.659]    [Pg.192]    [Pg.195]    [Pg.69]    [Pg.171]    [Pg.8]    [Pg.340]    [Pg.442]    [Pg.88]    [Pg.74]    [Pg.349]    [Pg.597]    [Pg.240]    [Pg.94]    [Pg.95]    [Pg.158]    [Pg.156]   
See also in sourсe #XX -- [ Pg.69 ]

See also in sourсe #XX -- [ Pg.156 , Pg.204 ]

See also in sourсe #XX -- [ Pg.32 , Pg.35 ]




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