دورية أكاديمية
Quantifying the effect of membrane potential in chemical osmosis across bentonite membranes by virtual short-circuiting.
| العنوان: | Quantifying the effect of membrane potential in chemical osmosis across bentonite membranes by virtual short-circuiting. |
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| المؤلفون: | Heister K; Department of Earth Sciences-Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, The Netherlands. heister@geo.uu.nl, Kleingeld PJ, Gustav Loch JP |
| المصدر: | Journal of colloid and interface science [J Colloid Interface Sci] 2005 Jun 01; Vol. 286 (1), pp. 294-302. |
| نوع المنشور: | Journal Article |
| اللغة: | English |
| بيانات الدورية: | Publisher: Academic Press Country of Publication: United States NLM ID: 0043125 Publication Model: Print Cited Medium: Print ISSN: 0021-9797 (Print) Linking ISSN: 00219797 NLM ISO Abbreviation: J Colloid Interface Sci Subsets: PubMed not MEDLINE |
| أسماء مطبوعة: | Publication: Orlando, FL : Academic Press Original Publication: New York. |
| مستخلص: | Clay liners are charged membranes and show semipermeable behavior regarding the flow of fluids, electrical charge, chemicals and heat. At zero gradients of temperature and hydrostatic pressure, a salt concentration gradient across a compacted clay sample induces not only an osmotic flux of water and diffusion of salt across the membrane but also an electrical potential gradient, defined as membrane potential. Laboratory experiments were performed on commercially available bentonite samples in a rigid-wall permeameter connected to two electrically insulated fluid reservoirs filled with NaCl solutions of different concentrations and equipped with Ag/AgCl electrodes to measure the electrical potential gradient. The effect of membrane potential could be cancelled out by short-circuiting the clay with the so-called virtual shortcut. The potential gradient across the sample is brought to zero with a negative feedback circuit. It was observed that the water flux and the diffusion of Cl- were hindered by the occurrence of a membrane potential, indicating that an electroosmotic counterflow is induced. Flow parameters were calculated with modified coupled flow equations of irreversible thermodynamics. They were in excellent agreement with values reported in the literature. Comparing the method of short-circuiting with a study elsewhere, where the electrodes were physically short-circuited, it was shown that the virtual shortcut is more appropriate because physically short-circuiting induces additional effects that are attributed to the fluxes. |
| تواريخ الأحداث: | Date Created: 20050426 Date Completed: 20061101 Latest Revision: 20091111 |
| رمز التحديث: | 20240628 |
| DOI: | 10.1016/j.jcis.2005.01.044 |
| PMID: | 15848431 |
| قاعدة البيانات: | MEDLINE |
Full Text Finder | تدمد: | 0021-9797 |
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| DOI: | 10.1016/j.jcis.2005.01.044 |