A radial flow streaming potential apparatus for electrokinetic studies of sheet or plate materials

A radial flow streaming potential (r.f.s.p.) apparatus, and the procedure adopted for streaming potential determination, are described. It is shown by consideration of apparatus design and by experiment that the conditions necessary for valid application of the Helmholtz-Smoluchowski equation for zeta-potential calculation are satisfied by the r.f.s.p. technique. Zeta-potential data for fused silica discs determined by the r.f.s.p, technique are found to be in good agreement with previous studies on other forms of silica. Application of the Gouy-Chapman- Stern-Grahame double-layer theory to enable calculation of surface potential (ψo) shows it to be independent of salt concentration and to change by 30 mV per pH unit, both results providing verification of the soundness of the r.f.s.p. technique.

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The electrical double-layer properties of the mica (muscovite)-aqueous electrolyte interface

Australian Journal of Chemistry ◽

10.1071/ch9811177 ◽

1981 ◽

Vol 34 (6) ◽

pp. 1177 ◽

Cited By ~ 44

Author(s):

JS Lyons ◽

DN Furlong ◽

TW Healy

Keyword(s):

Zeta Potential ◽

Double Layer ◽

Electrical Double Layer ◽

Negative Charge ◽

Aqueous Electrolyte ◽

Streaming Potential ◽

Electrolyte Interface ◽

Muscovite Mica ◽

Silica Alumina ◽

Flow Apparatus

Electrophoresis and streaming potential data are reported for crushed and sheet muscovite mica respectively. For streaming potential measurements a newly designed radial flow apparatus was used. Measurements on crushed mica show that both aluminium and silicon leach out of the mica. Leached aluminium and silicon may readsorb to confer increased positive and negative charge respectively on the mica. Electrophoresis data indicate that leaching of aluminium occurs more rapidly than of silicon. Aging experiments on sheet mica show leaching effects to be much slower than on crushed mica. Streaming potential measurements on freshly cleaved mica sheets showed that (i) the zeta- potential depended strongly on electrolyte (KCl) concentration; (ii) the zeta-potential was relatively independent of pH and (iii) monovalent cations were adsorbed in the sequence H+ > Cs+ > K+ > Na+ > Li+, whilst Ca2+ adsorbed more strongly than K+. It is proposed that the structure of the electrical double layer at the mica/electrolyte interface results from the distribution of all ions between the diffuse layer, the Stern plane (hydrated) and more critically the lattice holes of the silica-alumina basal plane.

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Examination of the fractal model for streaming potential coefficient in porous media

VNU Journal of Science Mathematics - Physics ◽

10.25073/2588-1124/vnumap.4306 ◽

2019 ◽

Vol 35 (1) ◽

Author(s):

Luong Duy Thanh

Keyword(s):

Experimental Data ◽

Porous Media ◽

Zeta Potential ◽

Streaming Potential ◽

Fractal Model ◽

Potential Coefficient ◽

Proposed Model ◽

Alternative Approach ◽

High Fluid ◽

Good Agreement

In this work, the fractal model for the streaming potential coefficient in porous media recently published has been examined by calculating the zeta potential from the measured streaming potential coefficient. Obtained values of the zeta potential are then compared with experimental data. Additionally, the variation of the streaming potential coefficient with fluid electrical conductivity is predicted from the model. The results show that the model predictions are in good agreement with the experimental data available in literature. The comparison between the proposed model and the Helmholtz-Smoluchowski (HS) equation is also carried out. It is seen that that the prediction from the proposed model is quite close to what is expected from the HS equation, in particularly at the high fluid conductivity or large grain diameters. Therefore, the model can be an alternative approach to obtain the zeta potential from the streaming potential measurements.

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How to use alum with cationic dispersed rosin size

TAPPI Journal ◽

10.32964/tj15.5.331 ◽

2016 ◽

Vol 15 (5) ◽

pp. 331-335 ◽

Cited By ~ 3

Author(s):

LEBO XU ◽

JEREMY MYERS ◽

PETER HART

Keyword(s):

Zeta Potential ◽

Colloidal Particles ◽

Streaming Potential ◽

Excessive Amount ◽

Paper Machine ◽

Optimum Amount ◽

Potential Measurement ◽

Streaming Current ◽

Wide Range ◽

Laboratory Results

Retention of cationic dispersed rosin size was studied via turbidity measurements on stock filtrate with different alum and dispersed rosin size dosages. Stock charge characteristics were analyzed using both an analysis of charge demand determined via a streaming current detector and an evaluation of zeta potential of the fibers by streaming potential measurement. The results indicated that an optimum amount of alum existed such that good sizing retention was maintained throughout a wide range of dispersed rosin size dosages. However, when an excessive amount of alum was used and fines and colloidal particles were transitioned from anionic to cationic, the cationic size retention was reduced. Laboratory results were confirmed with a paper machine trial. All data suggested that a stock charge study was necessary to identify optimal alum dosage for a cationic dispersed rosin sizing program.

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Prediction of Defects in Multistage Cold Forging by Using Finite Element Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.622-623.659 ◽

2014 ◽

Vol 622-623 ◽

pp. 659-663 ◽

Cited By ~ 1

Author(s):

Fabio Bassan ◽

Paolo Ferro ◽

Franco Bonollo

Keyword(s):

Radial Flow ◽

Surface Defects ◽

Plastic Instability ◽

Cold Forging ◽

Formation Mechanisms ◽

Fe Model ◽

Pipe Fitting ◽

Tooling Design ◽

Simulated Flow ◽

Good Agreement

In this work, the formation mechanisms of surface defects in multistage cold forging of axisymmetrical parts have been studied through FEM simulations. As case history, the industrial production of an heating pipe fitting by cold forging has been analyzed. Based on simulated flow behaviour of material, several types of surface defects are identified and attributed to plastic instability of the work-material, inappropriate axial/radial flow ratio, excessive forming-pressure and uncorrect tooling design. The results of the FE model are finally compared with those obtained from real forging process and good agreement is observed.

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Effect of clay colloids on the zeta potential of Fe/Al oxide-coated quartz: a streaming potential study

Journal of Soils and Sediments ◽

10.1007/s11368-016-1463-9 ◽

2016 ◽

Vol 16 (12) ◽

pp. 2676-2686 ◽

Cited By ~ 7

Author(s):

Zhong-yi Li ◽

Ren-kou Xu ◽

Jiu-yu Li ◽

Zhi-neng Hong

Keyword(s):

Zeta Potential ◽

Streaming Potential ◽

Potential Study ◽

Al Oxide

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Combined measurement of surface potential and zeta potential at insulator/electrolyte interfaces

TRANSDUCERS '91: 1991 International Conference on Solid-State Sensors and Actuators. Digest of Technical Papers ◽

10.1109/sensor.1991.148922 ◽

2002 ◽

Author(s):

L.J. Bousse ◽

S. Mostarshed ◽

D. Hafeman

Keyword(s):

Zeta Potential ◽

Surface Potential

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The Determination of Electrokinetic Coupling-Coefficient and Zeta Potential of Rock Samples by Electrokinetic Measurements

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.516-517.1870 ◽

2012 ◽

Vol 516-517 ◽

pp. 1870-1873 ◽

Cited By ~ 5

Author(s):

Jun Wang ◽

Heng Shan Hu

Keyword(s):

Zeta Potential ◽

Coupling Coefficient ◽

Streaming Potential ◽

Potential Method ◽

Surface Conductivity ◽

Reliable Estimate ◽

Surface Conductance ◽

Streaming Current ◽

Low Concentrations

The electrokinetic effects are important in the understanding of electric properties in porous medium. In this study, the streaming potential and streaming current of saturated samples are measured at different concentrations, then three methods are applied to obtain the zeta-potential and electrokinetic coupling coefficient. The study shows that the results obtained from streaming potential and streaming current methods agree well with each other, but the results obtained from simplified streaming potential method become seriously inaccurate at low concentrations due to the influence of surface conductance. This experimental study also provides a reliable estimate of the surface conductivity and its contribution to zeta-potential at given concentrations.

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Capillary water absorption by a porous cylinder

Journal of Building Physics ◽

10.1177/1744259117724523 ◽

2017 ◽

Vol 42 (2) ◽

pp. 120-124 ◽

Cited By ~ 1

Author(s):

Christopher Hall

Keyword(s):

Radial Flow ◽

Effective Porosity ◽

Capillary Absorption ◽

Porous Cylinder ◽

Capillary Water ◽

Cylinder Axis ◽

Flow Through ◽

Front Model ◽

Sharp Front ◽

Good Agreement

Capillary absorption (imbibition) of water by a porous cylinder is described by means of a Sharp-Front model. The cumulative absorption increases as (time)1/2 at early times, but more slowly as the wet front approaches the cylinder axis. Results are given in terms of dimensionless variables. Experimental data on plaster cylinders are in good agreement with theory. Estimates of the sorptivity and effective porosity of the material can be obtained. The model may be useful in testing drilled cores and may also be applied to radial flow through the wall of a porous tube (hence to conduits and arches).

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