Rate, actual

ADM = Minimum downcomer area, fT ATM = Minimum column cross-sectional area, fr CAF = Vapor capacity factor CAFo = Flood capacity factor at zero liquid load CFS = Vapor rate, actual ftVsec DT = Tower diameter, ft DTA = Approximate tower diameter, ft FF == Flood factor or design percent of flood, fractional FPL = Tray flow path length, in. 

However, as the pH—rate plot shows, at very low pH the observed rate actually decreases. Because, as the preceding argument shows, rate-determining dehydration should result in a pH-dependent rate at low pH, this decreased rate must mean that the rds has changed. This is reasonable, for at pH values well below the pKg of hydroxylamine, the decreasing proportion of the hydroxylamine in the unprotonated form will decrease the rate of the initial addition. At some pH, then, the rate of the addition step will fall below that of the dehydration step, and the observed rate curve will lie lower than the rate predicted for the dehydration. 

Volume Rate, Actual m /s Molecular Weight Viscosity, mPa-s Pressure, kPa (bar a) Temperature, °C Design Range, % of Normal... 

The rate of transfer of electrons in the external circuit 7, which is the rate actually measured by the ammeter, is the difference between rates of the dominant or forward reaction and the subsidiary or reverse reaction at each electrode, and it follows that... 

Unionized mercuric acetate is also a mercurating species, for the second-order rate coefficient for mercuration of benzene by mercuric acetate in acetic acid at 25 °C is 0.41 x 10"7. If mercuration took place via ionized acetate ion pairs HgOAc+OAc" for which AT, the equilibrium constant can be estimated at 2 x 10"8, then since the rate of mercuration by this ion pair will be approximately the same as by the acetoxymercury perchlorate ion pair for which k2 the second-order rate coefficient has been determined (above) as 0.37x10"3 at 25 °C, the observed second-order rate should be 2 x 10"8 x0.37 x 10"3 = 0.74xl0-11. This is so different from the rate actually observed that mercuration by the ion pair can be eliminated which leaves ionized mercurcy acetate as the only possible mercurating species439. 

If the concentration of an initiator does not virtually change throughout the experiment, then v = const, and oxidation must occur at a constant rate. Actually, the initiation rate decreases. If the initiator is a sole source of radicals in the system, the kinetics of oxidation is described by the equation [2] ... 

It may be noted that the field data on a per m2 catchment area basis, from different geographical areas are remarkably similar 10-2 — 101 equiv nr2 y1). In order to estimate from these rates, actual rates of dissolution of rocks on a per m2 mineral surface area basis, we have to know, how many m2 of effective (active) mineral surface is available per m2 geographic area. This is not known, but the estimate of 105... 

Quantities useful for predicting phase continuity and inversion in a stirred, sheared, or mechanically blended two-phased system include the viscosities of phases 1 and 2, and and the volume fractions of phases 1 and 2, and ij. (Note These are phase characteristics, not necessarily polymer characteristics.) A theory was developed predicated on the assumption that the phase with the lower viscosity or higher volume fraction will tend to be the continuous phase and vice versa (23,27). An idealized line or region of dual phase continuity must be crossed if phase inversion occurs. Omitted from this theory are interfacial tension and shear rate. Actually, low shear rates are implicitly assumed. 

In organic solids the determination of rotating frame relaxation is severely complicated by the presence of the strongly interacting proton spin system. Spin-spin fluctuations compete with spin-lattice fluctuations to produce an effective relaxation time large rf field amplitudes are mandated to discriminate against the spin-spin event. The burden of proof lies with the experimenter to establish that a rotating frame relaxation rate actually reflects a motional effect seen by the carbon nuclei. 

One might expect that this is an elementary reaction because the reaction agrees with the stoichiometry (after multiplying aU coefficients in the preceding expression by two). However, one peculiarity of this reaction is that the rate actually decreases with increasing temperature or has a negative activation energy, an unreasonable situation for an elementary process. 

The ratio of these rates (actual rate/ideal rate) is the fraction by which the rate is reduced by pore diffusion limitations, which we call rj, and this is the definition of the effectiveness factor. 

A recent investigation (79JOC4881) examining the effect of poly(ethylenimines) modified with 4-chloromethylimidazole on the hydrolysis of p-riitrophenyl caproate has shown that the rate actually decreases with increasing imidazole concentration, e.g. approximately a four-fold decrease when the imidazole concentration increased three-fold. This observation,... 

In order to determine rate constants rigorously in interfacial reactions, methods are required which allow determination of reactant concentrations and chemical rates actually at the reactive surface. This requires a degree of control of the hydrodynamics which is not available in stirred vessels, and more sophisticated methods are used in these cases. Minimal criteria for the unambiguous determination of interfacial chemical kinetics have been enumerated elsewhere and are as follows [13]. 

Therefore, biologically mediated kinetic fractionation, where the products will have more of the lighter isotope in them due to differential partitioning from higher energy properties, will result in a net depletion of the heavy isotope in the product and a more negative del value. Moreover, kinetic fractionation occurs in reactions that are unidirectional, where the reaction rates actually depend on the isotopic composition of the substrates and products. Thus, the isotopic ratio of the substrate is related to the amount... 

Gas holdup and volumetric gas-liquid mass-transfer coefficients are correlated with the gassed power input/volume and with the aeration rate (actual gas superficial velocity), e.g., the correlation of van t Riet [Ind. Eng. Chem. Proc. Des. Dev. 18 357 (1979)] for the volumetric mass-transfer coefficient of coalescing and noncoalescing systems ... 

Refinery profit as measured by the LP objective function increased as the incremental crude was charged to the refinery. At a point equal to about 50% of the available incremental crude, however, the profit function began to decline. The profit at maximum incremental crude rate actually ended up at a lower value than the initial LP case value using this parametric approach. 

Inlet waste gas flow rate, actual cubic feet per minute (acfm) 12,500... 

At higher acidities, typically 6 M HCl, complications arise the reaction loses its zero order dependence on the [nitrite trap] and the reaction rate actually decreases with increasing acidity for some of the nitrite traps (Biggs and Williams, 1976b). This can be accounted for by the extensive protonation expected for some of the nitrite traps (e.g. urea) at these acidities. 

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