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Copyright Brian J. Kirby. With questions, contact Prof. Kirby here. This material may not be distributed without the author's consent. When linking to these pages, please use the URL http://www.kirbyresearch.com/textbook.

This web posting is a draft, abridged version of the Cambridge University Press text. Follow the links to buy at Cambridge or Amazon or Powell's or Barnes and Noble. Contact Prof. Kirby here. Click here for the most recent version of the errata for the print version.

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Jump To: [Kinematics] [Couette/Poiseuille Flow] [Fluid Circuits] [Mixing] [Electrodynamics] [Electroosmosis] [Potential Flow] [Stokes Flow] [Debye Layer] [Zeta Potential] [Species Transport] [Separations] [Particle Electrophoresis] [DNA] [Nanofluidics] [Induced-Charge Effects] [DEP] [Solution Chemistry]

11.6 Summary [species/charge transport top]

In this chapter, we have described the basic sources of species fluxes, including constitutive relations such as the diffusivity, electrophoretic mobility, and viscous mobility. The species fluxes, when applied to a control volume, led to the basic conservation equations for species, the Nernst-Planck equations:

microfluidics textbook nanofluidics textbook Brian Kirby Cornell

This equation can be summed for all species and weighted by the species valence, leading to the charge conservation equation written here for negligible fluid flow and species with identical diffusivities:

microfluidics textbook nanofluidics textbook Brian Kirby Cornell

These equations lead to discussion of transport parameters D, μEP, μi, σ, and Λ, related by the Nernst-Einstein relation:

microfluidics textbook nanofluidics textbook Brian Kirby Cornell

and the definitions of conductivity and molar conductivity. These issues are central to nonequilibrium electrokinetic flow and microfluidic manipulation of chemical species.

[Return to Table of Contents]



Jump To: [Kinematics] [Couette/Poiseuille Flow] [Fluid Circuits] [Mixing] [Electrodynamics] [Electroosmosis] [Potential Flow] [Stokes Flow] [Debye Layer] [Zeta Potential] [Species Transport] [Separations] [Particle Electrophoresis] [DNA] [Nanofluidics] [Induced-Charge Effects] [DEP] [Solution Chemistry]

Copyright Brian J. Kirby. Please contact Prof. Kirby here with questions or corrections. This material may not be distributed without the author's consent. When linking to these pages, please use the URL http://www.kirbyresearch.com/textbook.

This web posting is a draft, abridged version of the Cambridge University Press text. Follow the links to buy at Cambridge or Amazon or Powell's or Barnes and Noble. Contact Prof. Kirby here. Click here for the most recent version of the errata for the print version.


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