Ratio, implied operation

This test determines the ratio of average S P Core Earnings to average reported net income for years 1997-2002 for each of the 189 companies entering this screen. A low Core Earnings to net income ratio implies that a company produced material earnings from noncore operating activities. 

Figure 5.33 Prereforming, bench-scale test (duration 2300 hours) [386], The low temperatures imply a low H20/CnHm ratio. Recycle operation results in an overall O/C ratio of 1.0 close to the carbon limits O/C=0.9 (as calculated from principle of...

The reflux ratio may vary between the limits of zero and infinity. At zero reflux ratio, the operation of a multistage process reduces to that of a single stage. This may be verified by setting L,/Vi to zero in Equation 3.21, which implies that F21 = Thus at zero reflux, the separation is lowest, being the same as in a single stage. 

Overfire air (OFA) is often used in conjunction with LNBs. As the name implies, OFA is injected into the furnace above the normal combustion zone. It is added to ensure complete combustion when the burners are operated at an air-to-fuel ratio that is lower than normal. 

This expression is known as the Stern-Volmer equation and Ksv as Stern-Volmer constant. Ksv is the ratio of bimolecular quenching constant to unimolecular decay constant and has the dimension of litre/mole. It implies a competition between the two decay pathways and has the ch".acter of an equilibrium constant. The Stern-Volmer expression is linear in quencher concentration and Ksv is obtained as the slope of the plot of 4>f°If vs [Q], if the assumed mechanism of quenching is operative. Here, t is the actual lifetime of the fluorescer molecule in absence of bimolecular quenching and is expressed as... 

In the limit as ftact the rate of reaction of encounter pairs is very fast. The Collins and Kimball [4] expression, eqn. (25), reduces to the Smoluchowski rate coefficient, eqn. (19). Naqvi et al. [38a] have pointed out that this is not strictly correct within the limits of the classical picture of a random walk with finite jump size and times. They note the first jump of the random walk occurs at a finite rate, so that both diffusion and crossing of the encounter surface leads to finite rate of reaction. Consequently, they imply that the ratio kactj TxRD cannot be much larger than 10 (when the mean jump distance is comparable with the root mean square jump distance and both are approximately 0.05 nm). Practically, this means that the Reii of eqn. (27) is within 10% of R, which will be experimentally undetectable. A more severe criticism notes that the diffusion equation is not valid for times when only several jumps have occurred, as Naqvi et al. [38b] have acknowledged (typically several picoseconds in mobile solvents). This is discussed in Sect. 6.8, Chap. 8 Sect 2.1 and Chaps. 11 and 12. Their comments, though interesting, are hardly pertinent, because chemical reactions cannot occur at infinite rates (see Chap. 8 Sect. 2.4). The limit kact °°is usually taken for operational convenience. 

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