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Scaling parameters concentration

Since the only angle dependence conies from 0 , and the actions /, L are constant. From this point onwards we concentrate on motion under the reduced Hamiltonian which depends, apart from the scaling parameter y, only on the values of scaled coupling parameter p and the scaled detuning term p. In other words, we investigate the monodromy only in a fixed J (or polyad number N = 2J) section of the three-dimensional quanmm number space. [Pg.81]

At this point two essential remarks have to be added. The first is concerned with the reduced concentration X =A2M c = c 2 hich is a rather universal scaling parameter. It indicates the fact that the same master curve is obtained whether for a special sample the concentration is changed or the molar mass is varied. Even the solvent can be changed as long as the good solvent condition remains fulfilled, i.e., the coil interpenetration function W(z) should have reached its plateau value Finally it may be noticed that at no stage of this outline did the chemical nature of the sample have to be introduced. In fact, measurements... [Pg.182]

At low flow velocity of the dispersed phase, the interfacial tension does not influence the droplet diameter but it affects the time-scale parameters for droplet formation [35-37] the detachment time becomes shorter at high interfacial tension (low surfactant concentration) [38]. [Pg.8]

Scaling as a Means to Compare Similar Systems. When the diffusion problem is invariant to the scaling parameter rj = x/s/ADt, equal values of t] can be used to determine relationships between length, time, and the value of the diffusivity. For example, consider two masses that differ only in their length dimension. Let the first block have length L and the second block have length aL. If at a time, r, a particular concentration appears at the center of the first block, the same concentration will appear in the second block at time a2r. [Pg.83]

Here, C( , z, t) is the scaled solute concentration in the fluid phase, Cw the solute concentration at the wall, 6 the normalized adsorbed concentration (O<0< 1), K the adsorption equilibrium constant, p the transverse Peclet number, T represents the adsorption capacity (ratio of adsorption sites per unit tube volume to the reference solute concentration), and Da is the local Damkohler number (ratio of transverse diffusion time to the characteristic adsorption time). We shall assume that p 4Cl while T and Da are order-one parameters. (In physical terms, this implies that transverse molecular diffusion and adsorption processes are much faster compared to the convection.)... [Pg.234]

Fig. 9.6 Concentrations of O3 (a) and NO2 (b) computed using RAMS (dotted line with triangles) and SURFPRO (solid line with diamonds) turbulent fluxes and scaling parameters vs. observations (grey squares)... Fig. 9.6 Concentrations of O3 (a) and NO2 (b) computed using RAMS (dotted line with triangles) and SURFPRO (solid line with diamonds) turbulent fluxes and scaling parameters vs. observations (grey squares)...
The S is the input concentration of nutrient (to the leftmost vessel), and D is the washout rate. These two parameters are under the control of the experimenter. The terms 7 and y, are the yield coefficients. For convenience, one can scale substrate concentrations S, by S , time by /D (making m, nondimensional and D = 1), and microorganism concentrations by and to obtain the less cluttered system... [Pg.131]

The computing problem is concerned with calculating the maximum number of unknown parameters of a proposed reaction system from available experimental data. This data can be any combination of values for constant parameters (rate and equilibrium constants) and variable parameters (concentration versus time data). Moreover, data for different variable parameters need not have the same time scale. When the unknown parameters are calculated, it is important that the mathematical validity of the proposed model be determined in terms of the experimental accuracy of the data. Also, if it is impossible to solve for all unknown parameters, then the model must be automatically reduced to a form that contains only solvable parameters. Thus, the input to CRAMS consists of 1) a description of a proposed reaction system model and, 2) experimental data for those parameters that were measured or previously determined. The output of CRAMS is 1) information concerning the mathematical validity of the model and 2) values for the maximum number of computable unknown parameters and, if possible, the associated reliabilities. The system checks for model validity only in those reactions with unknown rate constants. Thus a simulation-only problem does not invoke any model validation procedures. [Pg.44]

It is no longer meaningful to characterize the microscopic current distribution in terms of the Wa number since the latter incorporates the ohmic resistance as the source for non-uniformity, whereas on the micro-scale the concentration field is more important. Instead, the leveling parameter, L, has been formulated4 by replacing the ohmic resistance by mass transfer resistance (as the source for non-uniform flux) and comparing it to the kinetic resistance ... [Pg.29]

The variable u describes the local concentration of bromous acid HBr02, the variable v the oxidized form of the catalyst Ru(bpy)3", and w describes the bromide concentration. Here the parameter light intensity, and the photochemically-induced production of bromide is assumed to be linearly dependent on it, d Qv ]/dt(x4> [32]. e, e and q are scaling parameters, and / is a stoichiometric constant [47]. This model can be reduced to the two-component one by adiabatic elimination of the fast variable w (in the limit e e) [47]. In this case one gets the following two-component version of the Oregonator kinetics... [Pg.7]

A) Perceived magnitude (linear scale) vs. concentration of carbon dioxide (logarithmic scale) for carbon dioxide presented alone ( ). amyl butyrate presented alone (M), and mixtures of carbon dioxide and amyl butyrate (O). Parameter is concentration of amyl... [Pg.117]

FIGURE 6.3 Average Lennard-Jones scaling parameters for PPE/PS blend in the fuU range of concentration. (Recomputed from Utracki and Simha [2001].)... [Pg.255]

The generation of current induces fluxes of gases, liquid water, heat and charged particles in a cell. The distribution of the respective parameters (concentrations, fields etc.) is usually very non-uniform. Furthermore, the characteristic scale of parameters variation ranges from several micrometres (the thickness of the catalyst layer) to several metres (the length of the channel). In general, the problem of fuel cell modeling is multi-scale and multi-dimensional. [Pg.199]

Correlations of the scaling parameters with polymer molecular weight, concentration, and size are examined, a increases markedly with polymer molecular weight, namely a for r 1. r/ is 0.5 for large polymers (M larger than 400 kDa or so), but increases toward 1.0 or so at smaller M. Scaling parameters for the diffusion of star polymers do not differ markedly from scaling parameters for the diffusion of linear chains of equal size. [Pg.305]

To answer First, the concentration and molecular weight dependences of D, and Dp are considered. Second, having found that D, and Dp uniformly follow stretched exponentials in c, correlations of their scaling parameters and other polymer properties are examined. Third, for cases that examined a series of homologous polymers, a joint function of matrix... [Pg.347]

For a similar system, the shear viscosity was found to follow the power law model with yield (Pal et al. 1986). Owing to the presence of yield stress, the flow of concentrated emulsion was found to be facilitated by superposition of 10 Hz oscillation on the steady-state shear flow - up to 40 % energy saving was reported (Jezequel et al. 1985). More recently, the relative viscosity of emulsions was described in terms of scaling parameters (Pal 1997). Ten principal variables were incorporated into six dimensionless groups X, k, reduced time, h = t/(r n,dV8 kB T), relative density, = pd/pm> Peclet number, Pe = ti yd /SkeT, and Reynolds number. Re = p yd /4rin,. For the steady-state flow of well-stabilized emulsions, it was argued that the relative viscosity of emulsions should depend only on two... [Pg.776]

First-order reaction rate constants were determined over a wide variety of temperatures, stoichiometries, and TPP concentrations by using the isothermal DSC experiments as described previously. For the sake of comparison, the first-order rate constants at 150 C are plotted with respect to the same scaling parameters as were used... [Pg.142]

An ideal experimental approach seems to be the combination of a time-resolved single-pulse trace with a subsequent analysis of the resulting MWD. The time-resolved trace gives direct access to the radical concentration versus time (see figure 3.2) and all scaling parameters, i.e. [i ]o and are then directly at hand. [Pg.115]


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See also in sourсe #XX -- [ Pg.428 , Pg.432 ]




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Concentration parameter

Concentration scales

Parameter scale

Scaling parameters

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