Velocity anisotropy

Foam type Volume weight 7 Gas-filling factor G (%) Parameter P Longitudinal Wave Velocity Anisotropy coefficients (Eq. 30 a) Effective anisotropy coefficient q (Eq. 29)... 

In the (younger) field of cluster physics, semiclassical methods have been less systematically explored, although several applications exist [2, 119, 120]. The Vlasov equation suffers from the same formal [121] and numerical [122] deficiencies as its nuclear counterpart, and this defect can be cured in a similar (expensive) way [123]. A more promising alternative is here offered by TDTF [124]. Careful studies of the phase-space structure of the electron cloud in a cluster show that the local degree of anisotropy of the Fermi sphere remains reasonably small in the dynamical situations considered here. The situation is more gratifying than in the nuclear case, because of the overwhelming dominance of the dipole response in the cluster case, a mode for which velocity anisotropy is small. 

Bazsa and Epstein (1985) found that fronts in the nitric acid oxidation of iron(II) propagated as much as six times faster moving down a vertical tube than traveling up the same tube. This front velocity anisotropy, which we shall discuss in more detail later in this chapter, was a function of the tube diameter and could be eliminated by adding silica gel to the solution. 

Acknowledgments We are grateful to Pascal Rudel for his original contribution in simple classification of explosive-ncm explosdve compounds in terms of NO2 density and in analysing the crystalline structure of energetic compounds in relation to their ability to detonateand velocity anisotropy. 

Vernik L, Liu X (1997) Velocity anisotropy in shales a petrological study. Geophysics 62 521-532... 

Yet another technique, measuring ultrasonic velocity anisotropies in the vicinity of the NA transition, however, also find anisotropies consistent with crossover behaviour. Sonntag et al [52] studied the divergence of three elastic constants, the bulk compression constant A, the layer compression constant B and the bulk-layer coupling constant C. B and C have critical exponents that are unequal and are in between that of the 3DXY values and anisotropic scaling values. 

FIGURE 6.50 Forward-calculated crossplots of velocity ratios (a) velocity ratio p,v/ s,v = /s-i-i/544 for vertical wave propagation versus shear wave velocity nramalized by the factor V3 and (b) velocity anisotropy ratio Vp,v/Pp,h = /sss/sii for compressional wave propagation versus horizontal compressional wave velocity Kpj, normalized by the facttn- V3. 

Experimentally the attention has been attracted principally by the absorption [3] for which the anisotropy is easily observed. Only recently, detailed studies of the velocity anisotropy were published [4] in the case of a polymer liquid crystal. The advantage of a polymer is that the relaxation time is high such that at 1 Mhz the velocity anisotropy is almost 1%, The disadvantage is that this anisotropy is already almost independent of the frequency. 

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