Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Transversal functions

Green s transverse functions are defined through the generating functional (F-qiiation 33)... [Pg.689]

The transverse vertex functions are similar to Green s transverse functions (Equation 37) and the equation of the Equation 41 type... [Pg.690]

Iditional importance is that the vibrational modes are dependent upon the reciprocal e vector k. As with calculations of the electronic structure of periodic lattices these cal-ions are usually performed by selecting a suitable set of points from within the Brillouin. For periodic solids it is necessary to take this periodicity into account the effect on the id-derivative matrix is that each element x] needs to be multiplied by the phase factor k-r y). A phonon dispersion curve indicates how the phonon frequencies vary over tlie luin zone, an example being shown in Figure 5.37. The phonon density of states is ariation in the number of frequencies as a function of frequency. A purely transverse ition is one where the displacement of the atoms is perpendicular to the direction of on of the wave in a pmely longitudinal vibration tlie atomic displacements are in the ition of the wave motion. Such motions can be observed in simple systems (e.g. those contain just one or two atoms per unit cell) but for general three-dimensional lattices of the vibrations are a mixture of transverse and longitudinal motions, the exceptions... [Pg.312]

The TEMqq mode is a specially desirable case. This transverse mode, the Gaussian mode, is symmetric and has no nulls. It is preferred for many apphcations. Its intensity / as a function of radius r from the center of the beam is given by the equation... [Pg.4]

Radial density gradients in FCC and other large-diameter pneumatic transfer risers reflect gas—soHd maldistributions and reduce product yields. Cold-flow units are used to measure the transverse catalyst profiles as functions of gas velocity, catalyst flux, and inlet design. Impacts of measured flow distributions have been evaluated using a simple four lump kinetic model and assuming dispersed catalyst clusters where all the reactions are assumed to occur coupled with a continuous gas phase. A 3 wt % conversion advantage is determined for injection feed around the riser circumference as compared with an axial injection design (28). [Pg.513]

For annuli containing externally Hnned tubes the heat-transfer coefficients are a function of the fin configurations. Knudsen and Katz (Fluid Dynamics and Heat Transfer, McGraw-Hill, New York, 1958) present relationships for transverse finned tubes, spined tubes, and longitudinal finned tubes in annuli. [Pg.563]

If this is then divided into the previous enhancement ratio, q, it is possible to observe the way in which one stiffness increases at the expense of the other. Fig. 2.32 shows this transverse/axial stiffness ratio as a function of the depth of the corrugations. It may be seen that when the depth is less than four times the wall thickness then the axial stiffness ratio is better than the transverse stiffness ratio. However, when the depth is greater than four times the wall thickness then the transverse stiffness ratio dominates. [Pg.83]

Although stratification, according to the plot in Fig. 10, occurs continuously as increases, it is accompanied by a curious structural reorganization in transverse directions (i.e., parallel to the planar substrate). A suitable measure of transverse structure is the pair correlation function defined in Eq. (62). However, for simplicity we are concerned only with the in-plane pair correlation function defined as [see Eq. (62)]... [Pg.41]

Fig. 11(a) displays plots of the in-plane pair correlation function for s = 2. and 3.0 well outside the regime where K exhibits its first maximum (see Fig. 12). The plots indicate that the transverse structures of one- and two-layer fluids (see Fig. 10) are essentially identical and typical of dense Lennard-Jones fluids. However, the transverse structure of a two-layer fluid is significantly affected as the peak of K is approached, as can be seen in Fig. 11(b) where g (zi,pi2) is plotted for s = 2.55 and 2.75, which points... Fig. 11(a) displays plots of the in-plane pair correlation function for s = 2. and 3.0 well outside the regime where K exhibits its first maximum (see Fig. 12). The plots indicate that the transverse structures of one- and two-layer fluids (see Fig. 10) are essentially identical and typical of dense Lennard-Jones fluids. However, the transverse structure of a two-layer fluid is significantly affected as the peak of K is approached, as can be seen in Fig. 11(b) where g (zi,pi2) is plotted for s = 2.55 and 2.75, which points...
FIG. 12 The transverse isothermal compressibiUty Ky as a function of substrate separation s, (from Ref. 114). [Pg.44]

Nominal Pipe Size Inches Outside Diam- eter Inches Thicks ness (Based Inside Diameter on ANSI B36.10 wall thicknesses) Inside Diameter Functions (In Inches) Transverse Internal Area ... [Pg.587]

Nominal Outside Thick- Inside Inside Diameter Functions Transverse ... [Pg.588]

K = 63 M 1, Kb = 1.4M-1)47 lithium-7 (K = 14 M 1 K" = 0.5 M 1) 49) and for cesium-133 (K, st 50 M-1, K = 4M 1)S0). In the case of sodium-23, transverse relaxation times could also be utilized to determine off-rate constants k ff = 3 x 105/sec k"ff = 2x 107/sec47,51). Therefore for sodium ion four of the five rate constants have been independently determined. What has not been obtained for sodium ion is the rate constant for the central barrier, kcb. By means of dielectric relaxation studies a rate constant considered to be for passage over the central barrier, i.e. for jumping between sites, has been determined for Tl+ to be approximately 4 x 106/sec 52). If we make the assumption that the binding process functions as a normalization of free energies, recognize that the contribution of the lipid to the central barrier is independent of the ion and note that the channel is quite uniform, then it is reasonable to utilize the value of 4x 106/sec for the sodium ion. [Pg.192]

Figure 14 shows the displacement of the distribution function towards high / , i.e. the uncoiling of molecules under the influence of stretching for polyethylene (A = 3 x 10-9 m, N = 100 and T = 420 K). This displacement will be characterized by the position of the maximum of the distribution curve, the most probable value of / , i.e. j3m, as a function of x (Fig. 15). Figure 15 also shows the values of stresses a that should be applied to the melt to attain the corresponding values of x (o = xkT/SL, where S is the transverse cross-section of the molecule). [Pg.231]

It therefore follows from the transversality condition [Eq. (9-516)] that a physically admissible wave function u(k) can only be spacelike or a multiple of k , since k is a null vector. In the coordinate system in which... [Pg.553]

Each unit of structure in the oriented polymer will also be considered to possess transverse isotropy. Its orientation can therefore be defined by polar and azimuthal angles (0, tp), but the condition of transverse isotropy for the whole sample means that the observed second moment will depend only on functions of 0 (in fact, P200 and P400) the functions involving (p taking fixed average values. [Pg.93]

Finally, a given internuclear vector rjk takes a direction with respect to the 3 axis of the unit of structure defined by polar and azimuthal angles ( , r[). Because each unit possesses transverse isotropy, the second moment will involve functions of h, only, the functions of r being replaced by their average values. [Pg.93]

Fig. 10. Comparison of the measured refractive indices for PET film with values calculated from the orientation functions determined from n.m.r. assuming transversely isotropic structural units. I, Experimental points predicted values. Reproduced from Polymer by permission of the publishers, Butterworth Co (Publishers) Ltd. (C)... Fig. 10. Comparison of the measured refractive indices for PET film with values calculated from the orientation functions determined from n.m.r. assuming transversely isotropic structural units. I, Experimental points predicted values. Reproduced from Polymer by permission of the publishers, Butterworth Co (Publishers) Ltd. (C)...

See other pages where Transversal functions is mentioned: [Pg.425]    [Pg.425]    [Pg.2854]    [Pg.197]    [Pg.200]    [Pg.54]    [Pg.199]    [Pg.27]    [Pg.1733]    [Pg.112]    [Pg.84]    [Pg.149]    [Pg.155]    [Pg.211]    [Pg.395]    [Pg.281]    [Pg.300]    [Pg.538]    [Pg.42]    [Pg.542]    [Pg.36]    [Pg.926]    [Pg.161]    [Pg.3]   
See also in sourсe #XX -- [ Pg.519 ]




SEARCH



Correlation functions transverse

Transverse relaxation function

© 2024 chempedia.info