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Acceptor equilibrium activity

The equilibrium activity in a plant where fresh acceptor is continuously added can be expressed by Equation 18. [Pg.172]

The calculated equilibrium activities for the Tymochtee dolomite at various makeup rates of fresh acceptor are given in Table VII. At the make-up rate assumed in the feasibility study of 2%, the equilibrium activities are substantially lower than the value of 0.70 given—i.e., 0.32 and 0.43, respectively, for the cases where char combustion was and was not effected in the regenerator. [Pg.172]

In this solvent the reaction is catalyzed by small amounts of trimethyl-amine and especially pyridine (cf. 9). The same effect occurs in the reaction of iV -methylaniline with 2-iV -methylanilino-4,6-dichloro-s-triazine. In benzene solution, the amine hydrochloride is so insoluble that the reaction could be followed by recovery. of the salt. However, this precluded study mider Bitter and Zollinger s conditions of catalysis by strong mineral acids in the sense of Banks (acid-base pre-equilibrium in solution). Instead, a new catalytic effect was revealed when the influence of organic acids was tested. This was assumed to depend on the bifunctional character of these catalysts, which act as both a proton donor and an acceptor in the transition state. In striking agreement with this conclusion, a-pyridone is very reactive and o-nitrophenol is not. Furthermore, since neither y-pyridone nor -nitrophenol are active, the structure of the catalyst must meet the conformational requirements for a cyclic transition state. Probably a concerted process involving structure 10 in the rate-determining step... [Pg.300]

NeuA, has broad substrate specificity for aldoses while pyruvate was found to be irreplaceable. As a notable distinction, KdoA was also active on smaller acceptors such as glyceraldehyde. Preparative applications, for example, for the synthesis of KDO (enf-6) and its homologs or analogs (16)/(17), suffer from an unfavorable equilibrium constant of 13 in direction of synthesis [34]. The stereochemical course of aldol additions generally seems to adhere to a re-face attack on the aldehyde carbonyl, which is complementary to the stereoselectivity of NeuA. On the basis of the results published so far, it may be concluded that a (31 )-configuration is necessary (but not sufficient), and that stereochemical requirements at C-2 are less stringent [71]. [Pg.282]

Therefore, the activation energy of quasi-equilibrium conductivity changes as a logarithm of concentration of adsorption particles which, when the linear dependence between Nt and P is available, corresponds to situation observed in experiment [155]. We should note that due to small value m function (1.91) satisfactorily approximates the kinetics oit) A - B n(i + t/t>) observed in experiments [51, 167, 168]. Moreover, substantially high partial pressures of acceptor gas, i.e. at high concentrations of Nt expression (1.81) acquires the shape ait) Oait/toc) it,Nty " when t>toc>. This suggests that for... [Pg.65]

In some undisturbed subsurface systems, an equilibrium is established. Bacteria have acclimated to food sources, water availability, and electron acceptor types. The number and variety of microbial cells are balanced in this system. If the system is aerobic, the microbial activity continues at the rate of oxygen resupply. If the system is anaerobic, the rate of activity cannot exceed the accessibility of alternate electron acceptors. Generally, the subsurface (lower than the plant root zone) is relatively deficient in available carbon and electron acceptors. Under these normal semi-equilibrium conditions, a soil or aquifer system can consume organic materials within a reasonable range. When a chemical release is introduced into a well-established soil system, the system must change to react to this new energy source. The bacterial balance readjusts, in an effort to acclimate to the new carbon source. [Pg.405]


See other pages where Acceptor equilibrium activity is mentioned: [Pg.172]    [Pg.1573]    [Pg.369]    [Pg.2975]    [Pg.1453]    [Pg.228]    [Pg.510]    [Pg.365]    [Pg.116]    [Pg.143]    [Pg.575]    [Pg.255]    [Pg.262]    [Pg.649]    [Pg.651]    [Pg.653]    [Pg.654]    [Pg.162]    [Pg.189]    [Pg.116]    [Pg.212]    [Pg.213]    [Pg.218]    [Pg.23]    [Pg.2]    [Pg.65]    [Pg.101]    [Pg.504]    [Pg.40]    [Pg.233]    [Pg.69]    [Pg.677]    [Pg.306]    [Pg.158]    [Pg.66]    [Pg.241]    [Pg.158]    [Pg.96]    [Pg.407]    [Pg.341]    [Pg.138]    [Pg.159]    [Pg.22]    [Pg.1184]    [Pg.231]   


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Equilibrium activity

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