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Stationary constants

Newtonian liquid viscosity, U is the bubble velocity, and aQ is the equilibrium surface tension), where surface tension and viscous forces dominate the bubble shape (15). Using a lubrication analysis, Bretherton established that the bubble slides over a stationary, constant-thickness film whose thickness divided by the radius of the tube, h R., varies as the... [Pg.482]

Table 9.1 shows that the convective transport has a timescale on the order of 10-1 s. This time is the time it takes for gas to pass through the cell. Hence, for calculation times T much shorter than this duration, convective transport can be assumed stationary (constant), and Equations (9.10) and (9.11) can be ignored. On the other hand, for time steps At longer than this duration, the quasi-steady formula (where the left hand sides to (9.10) and (9.11) are both zero) can be used. For most cell performance problems, these model equations for the gas phase are normally integrated with the model equation for the sohd components (e.g., cell and interconnect) which is presented next. [Pg.286]

The contact estimate of this quantity obtained in Eq. (3.27) is different from the Markovian (stationary) constant (3.22). Both of them approach the same kinetic value fco when D —> oo (Fig. 3.10), but their asymptotic behavior at slow... [Pg.136]

Figure 3.10. The ideal Stern-Volmer constants Ko (solid lines) as functions of diffusion in the contact approximation (a) and for the exponential transfer rate with different tunnelling lengths / = 1.6A (b) and / = 2.5 A (c) (From Ref. 46.) The contact stationary constant k (dashed line) is shown for comparison with contact Kq (a). Figure 3.10. The ideal Stern-Volmer constants Ko (solid lines) as functions of diffusion in the contact approximation (a) and for the exponential transfer rate with different tunnelling lengths / = 1.6A (b) and / = 2.5 A (c) (From Ref. 46.) The contact stationary constant k (dashed line) is shown for comparison with contact Kq (a).
By criterion (3.151), the region is established where the energy transfer results in excitation quenching. At the border of this region, at xB = xA, the stationary constant (3.150) reaches the minimal value at given ka and kb... [Pg.165]

Let us introduce the stationary constants related to the kernels discussed above ... [Pg.292]

The infinitely long cylinder with no motion of the interface or of the fluid within the cylinder is, of course, a possible equilibrium configuration, in the sense that it is a surface of constant curvature so that the stationary constant-radius fluid satisfies all of the conditions of the problem, including the Navier-Stokes and continuity equations (trivially), as well as all of the interface boundary conditions including especially the normal-stress balance, which simply requires that the pressure inside the cylinder exceed that outside by the factor 1//a. The question for linear stability theory is whether this stationary configuration is stable to infinitesimal perturbations of the velocity, the pressure, or the shape of the cylinder. [Pg.802]

For a potential step experiment at a stationary, constant-area electrode, the charging current dies away after a time equivalent to a few time constants (/ uCd) (see Section 1.2.4). Since the potential is continuously changing in a potential sweep experiment, a charging current, /c always flows (see equation 1.2.15) ... [Pg.233]

The adaptive estimation of the pseudo-inverse parameters a n) consists of the blocks C and E (Fig. 1) if the transformed noise ( ) has unknown properties. Bloek C performes the restoration of the posterior PDD function w a,n) from the data a (n) + (n). It includes methods and algorithms for the PDD function restoration from empirical data [8] which are based on empirical averaging. Beeause the noise is assumed to be a stationary process with zero mean value and the image parameters are constant, the PDD function w(a,n) converges, at least, to the real distribution. The posterior PDD funetion is used to built a back loop to block B and as a direct input for the estimator E. For the given estimation criteria f(a,d) an optimal estimation a (n) can be found from the expression... [Pg.123]

A stationary ensemble density distribution is constrained to be a functional of the constants of motion (globally conserved quantities). In particular, a simple choice is pip, q) = p (W (p, q)), where p (W) is some fiinctional (fiinction of a fiinction) of W. Any such fiinctional has a vanishing Poisson bracket (or a connnutator) with Wand is thus a stationary distribution. Its dependence on (p, q) through Hip, q) = E is expected to be reasonably smooth. Quanttun mechanically, p (W) is die density operator which has some fiinctional dependence on the Hamiltonian Wdepending on the ensemble. It is also nonnalized Trp = 1. The density matrix is the matrix representation of the density operator in some chosen representation of a complete orthononnal set of states. If the complete orthononnal set of eigenstates of die Hamiltonian is known ... [Pg.385]

This leads to the quasi-stationary rate constant of equation (A3,4,133) if 4k + k +k f, which is... [Pg.789]

The results are simnnarized in table B2.5.5. The rate constants k- of individual decay chaimels may be obtained from the relative yields of all primary reaction products, which can be detennined in stationary experiments. [Pg.2141]

The hydrogen atom attached to an alkane molecule vibrates along the bond axis at a frequency of about 3000 cm. What wavelength of electromagnetic radiation is resonant with this vibration What is the frequency in hertz What is the force constant of the C II bond if the alkane is taken to be a stationary mass because of its size and the H atom is assumed to execute simple harmonic motion ... [Pg.166]

Table 11.13 McReynolds Constants for Stationary Phases in Gas Chromatography... Table 11.13 McReynolds Constants for Stationary Phases in Gas Chromatography...
Similar stationary phases Temp., °C McReynolds constants USP code... [Pg.1098]

Wagner and DUlont have described a low-shear viscometer in which the inside diameter of the outer, stationary cylinder is 30 mm and the outside diameter of the inner, rotating cylinder is 28 mm the rotor is driven by an electromagnet. The device operates at 135°C and was found to be free of wobble and turbulence for shear rates between 3 and 8 sec V The conversion of Eq. (2.7) to Eq. (2.9) shows that F/A = (i7)(dv/dr) (instrument constant) for these instruments Evaluate the instrument constant for this viscometer. [Pg.128]


See other pages where Stationary constants is mentioned: [Pg.155]    [Pg.371]    [Pg.671]    [Pg.694]    [Pg.1028]    [Pg.1075]    [Pg.1933]    [Pg.2333]    [Pg.2342]    [Pg.156]    [Pg.7]    [Pg.233]    [Pg.223]    [Pg.143]    [Pg.1284]    [Pg.1287]    [Pg.555]    [Pg.557]    [Pg.561]    [Pg.779]    [Pg.76]    [Pg.108]   


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