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Fractional power

The expected annual sales volume is important not only for estimating sales revenue, but also for the selection of plant capacity (20) or process type. An economy of scale is typical of many process operations because both investment and some operating costs tend to vary with capacity to a fractional power less than unity. [Pg.445]

Care should be taken in the case of roots and fractional powers of a product e.g., VxVy if x and y are negative. This rule applies if... [Pg.426]

An alternative to a factored estimate, in some cases, can be a scaled estimate if the battery limits cost of a similar plant is known, but the size is different. The cost of the new plant, C , is equal to the known plant cost, C, times the ratio of the two plants capacity raised to a fractional power. That is ... [Pg.235]

Implementation of the Kohn-Sham-LCAO procedure is quite simple we replace the standard exchange term in the HF-LCAO expression by an appropriate Vxc that will depend on the local electron density and perhaps also its gradient. The new integrals involved contain fractional powers of the electron density and cannot be evaluated analytically. There are various ways forward, all of which... [Pg.226]

OP, OPl, OP2 = outputs of the controllers, also fractional power applied to the heaters... [Pg.502]

The first-order and fractional power kinetics were also used to describe the behavior of DEHP biodegradation in the thermophilic phase, including the initial mesophilic phases (phase I) and the phase thereafter (phase II), respectively [62]. The fractional power kinetic model parameters, i.e., K and N. were calculated by (l)-(3) and derived from a plot of log (C/Co) versus log(f). The half time (f0.s) of DEHP degradation in phases I and II was calculated using first-order and fractional power kinetic equations (3), respectively. [Pg.127]

The determination of electron concentration by the frequency shift method is limited to time resolution greater than a few hundred nanoseconds and is therefore not applicable to liquids. The microwave absorption method can be used virtually down to the pulse width resolution. Under conditions of low dose and no electron loss, and assuming Maxwellian distribution at all times, Warman and deHaas (1975) show that the fractional power loss is related to the mean electron energy (E) by... [Pg.251]

Spiro [27] has derived quantitative expressions for the catalytic effect of electron conducting catalysts on oxidation-reduction reactions in solution in which the catalyst assumes the Emp imposed on it by the interacting redox couples. When both partial reaction polarization curves in the region of Emp exhibit Tafel type kinetics, he determined that the catalytic rate of reaction will be proportional to the concentrations of the two reactants raised to fractional powers in many simple cases, the power is one. On the other hand, if the polarization curve of one of the reactants shows diffusion-controlled kinetics, the catalytic rate of reaction will be proportional to the concentration of that reactant alone. Electroless metal deposition systems, at least those that appear to obey the MPT model, may be considered to be a special case of the general class of heterogeneously catalyzed reactions treated by Spiro. [Pg.230]

The case of parallel orientations (e J. Oz) differs radically from the previously considered one, since the frequency dependence of the spectral density function is specified by the fractional power law 109... [Pg.119]

File ex22-5.msp illustrates the implementation of the solution in each case. Note that, to avoid evaluation of zero to a fractional power, /B is bounded between zero and 0.9999. Note also that is not used for case (d). The results for /B for all cases, (a) to (d), are given in Table 22.1. Because of the way the problem is stated, with tj the same for each case, the result for case (d), all three rate processes involved, is an average of some sort of the results for cases (a) to (c), each of which involves only one rate process. The assumption of a single rate-controlling process introduces significant error in each of cases (a) to (c), relative to case (d). [Pg.566]

SLP and SQP usually generate points with large violations. This can cause difficulties, especially in models with log or fractional power expressions, because negative arguments for these functions may be generated. Such problems have been documented in reference to complex chemical process examples (Sarma and... [Pg.318]

This is a Dunham-like expansion but done around the anharmonic solution. It converges very quickly to the exact solution if the potential is not too different from that of a Morse oscillator (Figure 2.3). This will not, however, be the case for the highest-lying vibrational states just below the dissociation threshold. The inverse power dependence of the potential suggests that fractional powers of n must be included (LeRoy and Bernstein, 1970). [Pg.36]

While first-order models have been used widely to describe the kinetics of solid phase sorption/desorption processes, a number of other models have been employed. These include various ordered equations such as zero-order, second-order, fractional-order, Elovich, power function or fractional power, and parabolic diffusion models. A brief discussion of these models will be provided the final forms of the equations are given in Table 2. [Pg.190]

The Fractional Power or Power Function model can be expressed as ... [Pg.192]

We define the mass bias factor g = e and finally obtain the expression for the so-called mass-fractionation power-law as ... [Pg.126]

The variation of rate with a fractional power of the silver ion concentration can be explained if adsorption of the silver ions by the silver occurs prior to reaction and if the adsorption follows a Freundlich isotherm. The reaction rate then would be directly proportional to the concentration - of adsorbed silver ions, since the concentration of adsorbed ions would be related to that in solution by the equation... [Pg.113]

A more specific parameter that describes the separation capability is the fractionating power. Like selectivity, the fractionating power can be defined on the basis of the analyte property responsible for fractionation, that is, or for mass and diameter, respectively ... [Pg.338]

Fractionating power makes it possible to establish the relative increment in particle diameter or mass that can be separated with unit resolution. It can be demonstrated (by substituting Equations 12.14, 12.20, and 12.21b or c into Equation 12.22a or b, respectively) that F (or F ) can also by expressed by... [Pg.339]

Equation 12.23 shows that the fractionating power depends on both random dispersion, which is inversely related to N, and selective dispersion, which is defined by S. [Pg.339]

However, there have been some attempts to deal with this problem in general.Inspection of Eqs. (134) and (151) immediately reveals that the problem is due to the fractional power (i) raised on the effective density p ° (r) and the WAD (r). To preserve the integrity of the formulation, one can directly use p (r) and (r) instead, making no reference to their density... [Pg.153]

Examination of the results obtained by Katz et a as given in table 2 show rational fits between the experimental data and the equations of Van Deemter, Giddings and Knox. The fit of the data to both the Huber and Horvarth equations gave alternating positive and negative values for the D constant which is the coefficient of the term involving a fractional power of (u). Furthermore, for the Huber equation, the value of coefficient (E) is consistently zero and for the Horvath equation, is zero for four solvents mixtures out of six, with an extreme value of 97.3 for one solvent. [Pg.140]

For any solute, a is proportional to some fractional power of the molecular weight M, a power that depends on the shape of the molecule but will be the same for any series of similar molecules. If a = Mx for a certain type of molecule, then, for any series of solutes of this type on a gel of pore radius r, equation 10 may be written as... [Pg.27]

No explanation is offered for the peculiar fractional power dependence of the ignition delay times on fuel or oxygen concn. Nor is there any comment on what appears to be a low... [Pg.159]

KINETICS OF HETEROGENEOUS REACTIONS attached to the square root. It means simply a fractional power in the neighbourhood of 0-5. [Pg.210]


See other pages where Fractional power is mentioned: [Pg.820]    [Pg.854]    [Pg.2185]    [Pg.610]    [Pg.321]    [Pg.248]    [Pg.271]    [Pg.689]    [Pg.123]    [Pg.127]    [Pg.132]    [Pg.169]    [Pg.191]    [Pg.192]    [Pg.90]    [Pg.329]    [Pg.335]    [Pg.347]    [Pg.354]    [Pg.357]    [Pg.357]    [Pg.9]    [Pg.86]    [Pg.176]    [Pg.209]   
See also in sourсe #XX -- [ Pg.183 ]




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Fractionating power

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