Heterogeneity factor

The critical bridging index is thus the reciprocal of the heterogeneity factor H of the initial chains. 

Results of these investigations demonstrate that changes of the reactor surface can be an effective method for directing chemical reactions. Thus, developing a theory of how heterogeneous factors influence liquid-phase chain reactions is one of the important lines of advancement in this area. Only a few years ago it was thought, almost a priori, that there are practically no heterogeneous factors in liquid-phase oxidation and that liquid-phase processes differ from vapor-phase processes in this respect. 

Redlich-Peterson heterogeneity factor (dimensionless) radiation wavenumber (nm )... 

V V Azatyan, Reversible change of heterogeneous factors in branched chain processes, Kinet Katal (Rus 23 1301 (1982)... 

Because of these observations a study of optically active l-halo-l-methyl-2,2-diphenylcyclopropanes with solutions of sodium in liquid ammonia was undertaken As will be seen, the stereochemical results observed were shown to be dependent on the concentration of sodium in ammonia, the nature of the halogen and a heterogeneity factor. 

Here, K denotes the r.h.s. of Eq. (79) and A = Uo/kT is an heterogeneity factor which increases with increasing heterogeneity of the adsorbing surface. Homogeneous surfaces correspond to A = 0. At patchwise surfaces Eq. (80) should be solved numerically with respect to 0, and the total adsorption isotherm is determined again numerically from Eqs. (81) and (82). 

Wide variation of experimental conditions (temperature, total pressure, initial concentrations, heterogeneous factors) to display possible qualitative effects revealing intimate peculiarities of kinetic scheme. 

Where q and are defined as above, Kj, is the Fieundlich constant (L/mg), which indicates the relative adsorption capacity of the adsorbent related to the bonding energy, and n is the heterogeneity factor representing the deviation from hnearity of adsorption and is also known as Fretmdlich coefficient. According to Eq. (12.8), the plot of the log q versus log gives a straight line and the and n values can be... 

To find out the mechanism of a chemical reaction and the nature of its elementary processes it is very important to know whether the reaction occurs in the homogeneous (gas) phase only, or whether heterogeneous factors are also involved. With gas reactions such a factor usually is the reactor wall. The importance of the reactor wall, in particular of its nature and relative surface area in the kinetics of chemical gas reactions was first noticed by van t Hoff [499]. 

However, it has been found that, as a result of the dual wall effect, the reaction rate might sometimes be independent of S/V in spite of the occurence of heterogeneous reaction steps [230]. Therefore, the above method will give unambiguous indication that the heterogeneous factor is involved in the reaction only when the reaction rate depends on S/V. 

The method of differential calorimetry [50] is much more satisfactory both with regard to the unambiguity of interpretation of the results obtained and the quantitative estimation of the heterogeneous factor effect on the reaction rate. 

Physically, is a heterogeneity factor for vaporization exchange in the partially saturated porous electrode, while AHvapPw/Mw is the energy consumed for the evaporation of a unit volume of liquid water (P - P ) is the driving force for evaporation or condensation (depending on the sign), which is proportional to the difference of saturated and actual water vapor pressures. The product describes... 

Magomedov RN, Proshina AYu, Peshnev BV, Arutyunov VS. Effects of the Gas Medium and Heterogeneous Factors on the Gas-Phase Oxidative Cracking of Ethane. Kinet Catal 2013 54(4) 394—9. 

All of the experimental data lead to the necessary refinement of the known kinetic schemes at high pressure [57] (F > 1 MPa) and moderately high temperature (T < 1,000 K) [58-61]. Special attention should be paid to various additives (nitrogen oxides) and heterogeneous factor effects of confining surfaces. 

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