Plateau mobility

However, as we have mentioned, the averages in Eqs.(l6c) and (51) are not of the same sort self-trapping is expected to be important here, as it was for the mobility. Therefore, S 0 /15 cannot be the exact value predicted by the model instead, it plays the role of the plateau mobility before, i.e., it is the assymptotic value for JV0 >1. Figures 8-10 show the result of a computer simulation based on the BRM. 

VI.2 Computer Simulations of Crossed Field Electrophoresis We have studied crossed field electrophoresis using a computer simulation of the BRM . Fig. 13 shows a diagram of the mobility p/p vs pulse duration for 6 different molecular sizes, 4 of them having a size-independent plateau mobility p/pQ= Pp/Po continuous fields. 

The BRM has been successful in explaining continuous-field gel electrophoresis data. In particular, band-inversion, the "plateau" mobility and the p 1/L law are all accounted for by the BRM. Better quantitative agreement would be expected with a BRM which would include a pore size distribution, corresponding to a more realistic model of a gel, but a simple uniform gel model already describes most observed effects.. A number of power laws predicted by the BRM still need to be checked experimentally, however. 

As a guideline, the plateau rate is usually between 2 to 5% of the STOMP per year. The lower end of the range would apply to shallow dip reservoirs with an unfavourable mobility ratio, creating a rate dependent displacement process. 

Sowada and Warman (1982) have described a dc conductivity method for Ar gas at 295 K and 45 atm. Following a 20-ns pulse of irradiation, the conductivity rises to a peak at -50 ns, due to the Ramsauer effect, before settling to a plateau, which is ascribed to thermal conductivity since the collecting field is very low. Since there is little electron loss, the conductivity profile is proportional to the mobility profile this in turn can be considered a kind of image of collision frequency as a function of electron energy. The time to reach the conductivity plateau, -150 ns, is the measure of thermalization time in the present case. At a density of -9 X 1021 cm-3, the conductivity maximum vanishes, indicating the disappearance of the Ramsauer minimum according to Sowada and Warman. 

The value for k will normally decrease as the concentration of the solution decreases but the value for A will increase because of the increased dissociation of molecules in dilute solutions. A value for the molar conductance at infinite dilution (A,)) can be determined by plotting the calculated values for A against the molar concentration of the solution used and determining the plateau value for A. From such investigations it is possible to determine the ionic mobilities of ions (Table 4.3) and calculate the molar conductance of an... 

In multifunctional monomer polymerizations, the mobility of radicals through segmental diffusion falls well before their mobility through reaction diffusion at very low functional group conversions (as compared to linear polymerizations). From this point in the reaction, the termination and propagation kinetic constants are found to be related, and the termination kinetic constant as a function of conversion may actually exhibit a plateau region. Figure 6 illustrates the typical behavior of kp and k, vs conversion as predicted by a kinetic based model. 

The study of the dispersion of photoinjected charge-carrier packets in conventional TOP measurements can provide important information about the electronic and ionic charge transport mechanism in disordered semiconductors [5]. In several materials—among which polysilicon, a-Si H, and amorphous Se films are typical examples—it has been observed that following photoexcitation, the TOP photocurrent reaches the plateau region, within which the photocurrent is constant, and then exhibits considerable spread around the transit time. Because the photocurrent remains constant at times shorter than the transit time and, further, because the drift mobility determined from tt does not depend on the applied electric field, the sample thickness carrier thermalization effects cannot be responsible for the transit time dispersion observed in these experiments. 

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