HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Dudley, L. M. Articles by Junkermeier, C. Search for Related Content PubMed Articles by Dudley, L. M. Articles by Junkermeier, C. Agricola Articles by Dudley, L. M. Articles by Junkermeier, C. Related Collections Soil Surface Chemistry Soil Methods/Instrumentation Soil Chemistry

Low Frequency Impedance Behavior of Montmorillonite Suspensions

Polarization Mechanisms in the Low Frequency Domain

^a Dep. of Plants, Soils and Biometeorology, Utah State University, Logan, UT 84322
^b Northeast Foundation Utilities Professor, Dep. Civil and Environmental Engineering, Univ. of Connecticut, 261 Glenbrook Road, Unit 2037, Storrs, CT 06269-2037
^c Chemistry and Biochemistry Dep., Utah State University, Logan, UT 84322
^d Physics Dep., Utah State University, Logan, UT 84322

View larger version (17K): [in a new window]   Fig. 1. (a) A schematic representation (brick model) of the assembly of the clay and solution effective media and (b) the corresponding equivalent circuit (Bonanos et al., 1981). Re is the electrode impedance, gs is the conductivity of the solution element, cs is the capacitance of the solution element, gc is the conductivity of the moist clay element, and cc is the capacitance of the moist clay element.

View larger version (21K): [in a new window]   Fig. 2. An impedance plane plot of the real (') and imaginary (") components of the impedance, Z, and modulus, M (-1), for the small particle-size separate of Ca-saturated clay (data collected at 55°C).

View larger version (18K): [in a new window]   Fig. 3. Real and imaginary components of the immittance (Z/R0) spectrum for the small particle size separate of Ca-saturated clay (at 55°C). The fit curve is reproduced from the relaxation time distributions estimated from an expectation maximization algorithm.

View larger version (14K): [in a new window]   Fig. 4. Relaxation time distribution (a) extracted from the imaginary component of the immittance (Z"/R0) spectrum for the small particle size separate, Ca-saturated clay suspension. The temperature of the suspension was 55°C.

View larger version (21K): [in a new window]   Fig. 5. Measured and equivalent-circuit model predicted impedance spectra for the small particle-size separate of the Ca-saturated (a) and Na-saturated (b) clay at 25°C.

View larger version (17K): [in a new window]   Fig. 6. Measured and equivalent circuit model predicted impedance spectra for the Ca-saturated clay using the clay element conductivity computed for the Na-saturated clay.

View larger version (19K): [in a new window]   Fig. 7. The real components of the permittivity (a) and conductivity (b) computed by the Debye-relaxation model and measured for the Ca-clay suspension.

View larger version (20K): [in a new window]   Fig. 8. The real components of the permittivity (a) and conductivity (b) computed by the Debye-relaxation model and measured for the Na-clay suspension.

View larger version (18K): [in a new window]   Fig. 9. The real components of the permittivity (a) and conductivity (b) computed by the mixing model and measured for the Ca-clay suspension.

View larger version (18K): [in a new window]   Fig. 10. The real components of the permittivity (a) and conductivity (b) computed by the mixing model and measured for the Na-clay suspension.