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1

An effect of electrokinetics phenomena on nonlinear wave propagation in bubbly liquids

Panahov G., Abbasov E., Bakhtiyarov S., Museibli P.

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 3

177--186

EN

A study of nonlinear waves in liquid-gas mixtures with the consideration of internal effects is an important problem of both the fundamental and the applied fluid mechanics. Investigation of nonlinear waves in the gas-liquid mixtures with allowance for internal effects is an important task of both fundamental and applied fluid mechanics. These problems often arise in industrial processes such as oil and gas production, hydrocarbons pipeline transportation, gas-saturated fluids flow in pipelines, etc. In this work, we investigate the effect of the internal electric field on the nonlinear wave propagation in a bubbly liquid. Numerical simulations have been conducted to study the nonlinear waves described by the nonlinear Burgers-Korteweg-de Vries equation. The numerical simulations showed that the electrokinetic processes significantly affect the wave propagation process. The amplitude of the waves gradually decreases when the size of the gas bubble is decreasing and the electrical potential increases. A good agreement of obtained results with our previous predictions is found.

2

Relationship between the rheological parameters and zeta potential of bentonites

Kowalczyk D., Wach M., Plewik A., Wysocki S.

AGH Drilling, Oil, Gas

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2016

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Vol. 33, no. 4

663--669

EN

The paper presents an estimation of bentonites quality using electrokinetic phenomena occurring in dispersed clay systems. The idea behind the work is to demonstrate the relationship between the rheological parameters of the tested materials, and their zeta potential and consequently determine the suitability of these criteria for preparing drilling fluids.

3

Electrokinetic Phenomena of Cationised Cotton and its Dyeability with Reactive Dyes

Grancarić A. M., Ristic N., Tarbuk A., Ristic L.

Fibres & Textiles in Eastern Europe

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2013

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Vol. 21, no. 6 (102)

106--110

EN

Interface phenomena have a significant role in the wet finishing processes. Therefore in this paper the electrokinetic phenomena of cotton fabric cationised with a commercial cationic compound were researched. After cationisation, characterisation of the surface and chemical composition was performed by FTIR-ATR. Electokinetic phenomena - Zeta potential, Isoelectric point (IEP) and Point of zero charge (PZC), were determined according to the streaming current/streaming potential method and a specific amount of surface charge according to the back-titration method. The affinity of such modified cotton to reactive dyestuff of different functional groups was investigated through the K/S values. The influence of electrolyte addition to the dye bath was investigated as well.

PL

Zjawiska występujące na granicy faz odgrywają znaczącą rolę w mokrych procesach wykończeniowych, dlatego w niniejszej pracy zbadane zostały zjawiska elektrokinetyczne występujące w kationizowanej handlowym związkiem kationowym tkaninie bawełnianej. Po kationizacji przeprowadzono charakterystykę powierzchni i składu chemicznego używając do tego celu spektroskopii FTIR ATR. Zjawiska elektrokinetyczne tj. potencjał elektrokinetyczny, punkt izoelektryczny (IEP) i punkt ładunku zerowego (PZC) zostały ustalone zgodnie z metodą prądu/potencjału strumieniowego, a charakterystyczną wielkość ładunku powierzchniowego określono metodą miareczkowania odwrotnego. Powinowactwo zmodyfikowanej bawełny do barwnika reaktywnego różnych grup funkcyjnych było badane przez określenie wartości K/S. Badano również wpływ dodatku elektrolitu do kąpieli barwiącej.

4

Symetria przepływów jonowych

Kucharczyk A., Kubik J.

Roczniki Inżynierii Budowlanej

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2008

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z. 8

41--44

EN

The symmetry of equations of mass and electrical charge was analyzed. From these equations the correlation of the flows of mass and ions in the porous medium was estimated. This expression can be used to determine the coefficient of conductivity of ions in porous medium.

5

The application of electrokinetic zeta potential for determining electrostatic properties of dielectric liquid mixtures.

Zdanowski M., Kędzia J.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

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2007

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Vol. 46, nr 19

205-208

EN

The paper presents research results of electrokinetic zeta potential that exists in the electrical double layer on the border of the solid and liquid phases. For zeta potential examination, samples in the colloid form were used, the continuous (dispersing) phase of which was constituted by dielectric liquid mixtures formed on the base of simple hydrocarbons (hexane, cyclohexane, toluene), and the solid (dispersed) phase was constituted by materials in a disintegrated form (aluminum, copper, steatite, Al-70). The measurements were taken with Zetasizer 2000 - by Malvern Instruments (UK). Volume density of charge qw on the border of the solid and liquid phases, responsible for generation of electrostatic charges, was determined based on the measured zeta potential and physicochemical properties of the liquids under study.

6

Zastosowanie języka VHDL-AMS do modelowania zjawisk elektrokinetycznych w mikrosystemach

Ślusarczyk K.

Mikroelektronika i Informatyka : prace naukowe

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2006

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Z. nr 6

21-25

7

Studies on species dispersion in microchannels

Ślusarczyk K.

Mikroelektronika i Informatyka : prace naukowe

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2004

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Z. nr 4

179-188

EN

Lab-on-a-Chip devices begin to play more significant role in everyday life. The variety of implementations influences on devices' dimensions reduction. The side-effect of miniaturization is the necessity of microchannels bending, what is the major source of samples' dispersion during electrokinetic processes. Studies on this phenomenon allow for developing methods which will shorten drastically the Lab-on-a-Chip design path and also to reduce the dispersion itself in microchannels. Results obtained during simulations of basic microchannels structures are presented in this paper.

PL

Systemy MEMS (Micro-Electro-Mechanical Structures) odgrywają coraz bardziej znaczącą rolę we współczesnym świecie, różnorodność ich zastosowań sprawia, że można je spotkać we wszytkich dziedzinach życia, począwszy od czujników przyspieszenia w samochodach, poprzez żyroskopy w rakietach i samolotach, dyszach drukarek, a skończywszy na przenośnych laboratoriach biologiczno-chemicznych. Jednym z przykładowych urządzeń do zastosowań biologiczno-chemicznych jest tzw. Lab-on-a-Chip będący rodzajem przenośnego laboratorium, integrującego w sobie zarówno przetwarzającą sygnały część elektroniczną jak i zestaw kanałów doprowadzających ciecze bądź gazy do odpowienich komór celem ich analizy, syntezy związków, mieszania, detekcji, etc.

8

Influence of adsorbed colloid particles on streaming potential

Adamczyk Z., Warszyński P., Zembala M.

Bulletin of the Polish Academy of Sciences. Chemistry

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1999

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Vol. 47, No. 3

239-258

EN

A new theoretical model was developed for describing changes in streaming potential arising for surfaces covered by adsorbed colloid particles. The laminar flow in a channel of a rectangular cross-section, governed by the Navier-Stokes equation, was solved analytically in the form of a series expansion. Then, assuming the thin electrical doublelayer approximation a general expression for streaming potential was derived for channels having arbitrary surface charge. The influence of adsorbed particles on streaming potential was quantitatively determined by considering the perturbation to the macroscopic shearing flow due to a particle attached to the surface. Two effects were considered: (i) the change in the streaming potential due to flow damping in the vicinity of adsorbed par-ticle, and (ii) the change due to charge transport out from the double layer surrounding adsorbed particles. It was found that both effects were proportional to surface coverage of particles ( for not too high coverages) with the proportionali ty constants determined from appropriate surface integrals to be C(i)(O) = -10.21 and 02 = 6.51. These values, valid for thin double-layers, are independent of particle size, channel shape and ionic strength of the electrolyte. These theoretical predictions were confirmed for channels composed of natural mica sheets covered by positively charged latex particles. Particle coverage e was determined directly by optical and electron microscope counting procedure. A quantitative agreement of the theoretical model with experimental results was found for low coverages. Using the low coverage results an interpolating function was proposed which describes well the adsorbed particle effect for the entire range of coverages. Based on this function anew formula was derived for calculating particle coverage from measured changes of streaming potential. This enables one to determine accurately particle surface coverage in situ by following streaming potential changes.