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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]

16.6 Supplementary reading [AC electrokinetics top]

Early derivations of double layer capacitances can be found in [84175]. Bazant and co-workers have studied electrical double layer dynamics in great detail with a view towards managing the fluid flow in nonequilibrium electrical double layers developed at electrodes or metallic surfaces [1721768788177178179], and this chapter draws directly from that work. Castellanos, Ramos, Green, and Morgan have presented [180181182173] descriptions of AC electroosmosis effects and [174] shows net pumping by asymmetric electrodes. [183] shows use of traveling waves to generate DC pumping.

Much current attention is focused on the challenges regarding quantitative predictions of induced-charge phenomena—the fluid velocity magnitudes (and even signs) predicted by analysis described in this chapter often do not match experiment, an issue discussed in detail in [179]. di Caprio has presented modified Poisson-Boltzmann theories with attention to capacitance effects [184]. A review by Dukhin [137] focuses on the equilibrium assumptions made Chapter 13 and how departure from equilibrium affects colloidal motion and characterization of surfaces.

While the surfaces discussed in this chapter are all conducting, interfacial charge is also created when an electric field is applied normal to any interface with mismatched permittivity or conductivity—so electric fields applied to any insulating particle whose properties are not matched to its suspending medium creates interfacial charge. The resulting dipole on a particle is the source of dielectrophoretic forces, described in Chapter 17. This interfacial charge also induces fluid flow, with characteristic frequencies similar to that of the ACEO and ICEO flows described in this chapter. In fact, these flows are related to the variation in observed DEP response at kHz frequencies. As compared to the flows at conducting surfaces, though, the fluid flows induced at insulating objects tend to be smaller in scale.

[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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