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R C Tai

Publications and source records attributed to R C Tai.

6 recordsLinked to original sources
PubMed1980

Non-equimolar counter-diffusion in ternary gas systems.

Previous studies of multicomponent gas diffusion, using mathematical and physical models, have dealt with equimolar diffusion in closed systems. To simulate respiratory gas transport more faithfully, we have investigated ternary gas diffusion in open systems, which allow non-equimolar diffusion to occur. Theoretical results showed the effects of gas composition on the induced fluxes. A unique state in which the diffusion system satisfies both the equimolar and non-equimolar conditions was found for gas systems in which the net flux changes as the composition varies. To verify the non-equimolar film theory, we conducted experiments with a diffusion cell apparatus. Diffusional fluxes across a porous membrane were obtained for N2-O2-SF6, N2-O2-Ne, and N2-O2-He combinations. The experimental results agreed with the predicted values, validating the theoretical film approach.

Animals↗
PubMed1975

Some implications of ternary diffusion in the lung.

Diffusion in the lung normally involves three gases and the governing laws are Stefan-Maxwell equations rather than the more familiar Fick's law. A simple gas film model is studied mathematically to (1) demonstrate that the rate of diffusion of a component gas may be zero even though its concentration gradient is not zero (known as "diffusion barrier"), that the rate of diffusion of a component gas may not be zero even though its concentration gradient is zero ("osmotic diffusion"), and that a component gas may diffuse against the gradient of its concentration ("reverse diffusion"); (2) compare the discrepancy between results obtained by binary and ternary laws separately; (3) determine the importance of ternary diffusion at high pressure. The findings from the model study suggest that the effects of ternary diffusion may not be pronounced when air is breathed under normal conditions, but the behavior of helium mixtures deviate significantly from that described by binary diffusion laws.

Biological Transport↗