arXiv subjects

Edward Bormashenko

Publications and source records attributed to Edward Bormashenko.

42 records · Page 3Linked to original sources

arXiv2014

Hydrophilization of Liquid Surfaces by Plasma Treatment

The impact of the cold radiofrequency air plasma on the surface properties of silicone oils (polydimethylsiloxane) was studied. Silicone oils of various molecular masses were markedly hydrophilized by the cold air plasma treatment. A pronounced decrease of the apparent water contact angles was observed after plasma treatment. A general theoretical approach to the calculation of apparent contact angles is proposed. The treated liquid surfaces demonstrated hydrophobic recovery. The characteristic time of the hydrophobic recovery grew with the molecular mass of the silicone oil.

cond-mat.soft↗

arXiv2014

Probing Properties of Cold Radiofrequency Plasma with Polymer Probe

The probe intended for the characterization of cold plasma is introduced. The probe allows estimation of the Debye length of the cold plasma. The probe is based on the pronounced modification of surface properties (wettability) of polymer films by cold plasmas. The probe was tested with the cold radiofrequency inductive air plasma discharge. The Debye length and the concentration of charge carriers were estimated for various gas pressures. The reported results coincide reasonably with the corresponding values established by other methods. The probe makes possible measurement of characteristics of cold plasmas in closed chambers.

physics.plasm-ph↗

arXiv2014

Low Voltage Reversible Electrowetting Exploiting Lubricated Polymer Honeycomb Substrates

Low-voltage electrowetting-on-dielectric scheme realized with lubricated honeycomb polymer surfaces is reported. Polycarbonate honeycomb reliefs manufactured with the breath-figures self-assembly were impregnated with silicone and castor oils. The onset of the reversible electrowetting for silicone oil impregnated substrates occurred at 35 V, whereas for castor oil impregnated ones it took place at 80 V. The semi-quantitative analysis of electrowetting of impregnated surfaces is proposed.

cond-mat.soft↗

arXiv2011

Evaporation of droplets on strong and low-pinning surfaces and dynamics of the triple line

Evaporation of water droplets deposited on metal and polymer substrates was studied. The evaporated droplet demonstrates different behaviors on low-pinning (polymer) and strong-pinning (metallic) surfaces. When deposited on polymer surfaces, the evaporated droplet is featured by stick-slip sliding, whereas on strong-pinning metallic surfaces it does not show such kind of motion and demonstrates the giant contact-angle hysteresis. Stick-slip motion of droplets is described satisfactorily by the Shanahan-Sefiane model relating this kind of motion to surmounting potential barriers caused by the pinning of the triple (three-phase) line. The experimentally established "stick" times coincide with the values predicted by the Shanahan-Sefiane theory. The values of potential barriers are reported. The notion of the equilibrium contact angle is refined.

physics.chem-ph↗

arXiv2011

Electrically Deformable Liquid Marbles

Liquid marbles, which are droplets coated with a hydrophobic powder, were exposed to a uniform electric field. It was established that a threshold value of the electric field, 15 cgse, should be surmounted for deformation of liquid marbles. The shape of the marbles was described as a prolate spheroid. The semi-quantitative theory describing deformation of liquid marbles in a uniform electric field is presented. The scaling law relating the radius of the contact area of the marble to the applied electric field shows a satisfactory agreement with the experimental data.

cond-mat.soft↗

arXiv2010

Why do surface tensions of most of organic liquids demonstrate close values?

Values of surface tension of most of organic liquids are of the same order of magnitude. The natural explanation for this lies in the fact that surface tension is governed by London dispersion forces, which are independent of the permanent dipole moment of molecules. The surface tension of organic liquids (with the exception of polymers and polymer solutions) depends on the ionization potential and the diameter of the molecule only. These parameters vary slightly for organic liquids.

physics.chem-ph↗