Conjugation, effect Coupling constant

Eq. (1) has potential application to other types of measurements of substituent effects besides those specifically considered in this paper e.g., nmr coupling constants and shifts for other nuclei, ir and uv spectral shifts and intensities. We caution (with emphasis) in these applications the needed use of data sets of high quality, both with respect to the precision of the measurement and substituents considered (i.e., a full complement of substituent o/ and Or properties must be encompassed for a meaningful correlation to be obtained). There is, of course, no requirement that all data sets will be uniquely fitted by eq. (1) using one of the four or scales of Table V. For example, the data for the ionization of the conjugate acids of pyridine-N-oxides (30), HjO, 25° is found to fit equally well the or(ba.) or Or scales (SD=. 14 /=. 072). The data (31) for the rates of alkaline ("OMe) cleavage of ArSnMea are not fitted to acceptable precision (fs >. 23) by any of the Or parameters. This data set is nevertheless indicated... 

Since the temperature rise along the microchannel can be very large at very low values of the Reynolds number, for a fixed value of the wall heat flux, the thermophysical properties cannot be considered as constants in other words, the effects related to the variation of the thermophysical properties with temperature tend to be in general coupled with conjugate effects. It has been numerically demonstrated that in microchannel flows it becomes very important to take into account the variation of the fluid viscosity with the temperature in contrast, the other thermophysical properties can be considered as constant. 

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