Experimental Characterization of Mixing Efficiency

The experimental results were rather surprising. It appeared that no significant difference existed between the average values of mixing efficiency, heat transfer coefficient and pressure drop obtained in a pulsed flow and those obtained in a constant flow of the same mean rate, probably because of the very low pulsation frequency, which is superimposed to a turbulent motion characterized by frequences three orders of magnitude higher. Thus, as far as only average values are concerned, the... 

Other measures of efficiency are derived from the experimental RTD, which is characterized at least approximately by the variance This quantity is zero for plug flow and unity for complete mixing, and thus affords natural bounds to an efficiency eqiiated to the variance. It is possible, however, for the variance to fall out of the range (0,1) when stagnancy or bypassing occurs. 

Experimental studies [16] show that the best-characterized forms of the soluble MMO (sMMO) contain three protein components hydroxylase (MMOH), so-called B component (MMOB) and reductase (MMOR), each of which is required for efficient substrate hydroxylation coupled to NADH oxidation. The hydroxylase, MMOH, which binds O2 and substrate and catalyzes the oxidation, is a hydroxyl-bridged binuclear iron cluster. In the resting state of MMOH (MMOHqx), the diiron cluster is in the diferric state [Fe -Fe ], and can accept one or two electrons to generate the mixed-valence [Fe -Fe ] or diferrous state [Fe -Fe ], respectively. The diferrous state of hydroxylase (MMOHred) is the only one capable of reacting with dioxygen and initiating the catalytic cycle. 

The unusually small volume ratio of gas to liquid makes stripping plate efficiencies low. Yokota s model of the process assumes that liquid travels across a plate in uniform flow with no transverse mixing but that vertical mixing is perfect. He then characterizes a plate by the length of linear travel of the liquid. Correlation of the experimental data is in terms of the length of a transfer unit. This is the distance that liquid must travel to undergo an amount of mass transfer equivalent to one transfer unit. A plate then provides a (normally fractional) number of transfer units given by... 

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