Imperial College London
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DrMihaelaStevar

Central Faculty, Health and Safety Services

Process Safety Officer
 
 
 
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Contact

 

m.stevar

 
 
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Location

 

Open plan officeSherfield BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Stevar:2012:10.1016/j.jcis.2012.06.053,
author = {Stevar, MSP and Vorobev, A},
doi = {10.1016/j.jcis.2012.06.053},
journal = {J Colloid Interface Sci},
pages = {184--197},
title = {Shapes and dynamics of miscible liquid/liquid interfaces in horizontal capillary tubes.},
url = {http://dx.doi.org/10.1016/j.jcis.2012.06.053},
volume = {383},
year = {2012}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We report optical observations of the dissolution behaviour of glycerol/water, soybean oil/hexane, and isobutyric acid (IBA)/water binary mixtures within horizontal capillary tubes. Tubes with diameters as small as 0.2mm were initially filled with one component of the binary mixture (solute) and then immersed into a solvent-filled thermostatic bath. Both ends of the tubes were open, and no pressure difference was applied between the ends. In the case of glycerol/water and soybean oil/hexane mixtures, we managed to isolate the dissolution (the interfacial mass transfer) from the hydrodynamic motion. Two phase boundaries moving from the ends into the middle section of the tube with the speeds v∼D(1/3)t(-2/3)d(2) (D,t and d are the coefficient of diffusion, time and the diameter of the tube, respectively) were observed. The boundaries slowly smeared but their smearing occurred considerably slower than their motion. The motion of the phase boundaries cannot be explained by the dependency of the diffusion coefficient on concentration, and should be explained by the effect of barodiffusion. The shapes of the solute/solvent boundaries are defined by the balance between gravity and surface tension effects. The contact line moved together with the bulk interface: no visible solute remained on the walls after the interface passage. Changes in temperature and in the ratio between gravity and capillary forces altered the apparent contact angles. The IBA/water system had different behaviour. Below the critical (consolute) point, no dissolution was observed: IBA and water behaved like two immiscible liquids, with the IBA phase being displaced from the tube by capillary pressure (the spontaneous imbibition process). Above the critical point, two IBA/water interfaces could be identified, however the interfaces did not penetrate much into the tube.
AU  - Stevar,MSP
AU  - Vorobev,A
DO  - 10.1016/j.jcis.2012.06.053
EP  - 197
PY  - 2012///
SP  - 184
TI  - Shapes and dynamics of miscible liquid/liquid interfaces in horizontal capillary tubes.
T2  - J Colloid Interface Sci
UR  - http://dx.doi.org/10.1016/j.jcis.2012.06.053
UR  - https://www.ncbi.nlm.nih.gov/pubmed/22809545
VL  - 383
ER  -
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