The dynamic equilibrium model suggests that surface nanobubbles can be stable due to an influx of gas in the vicinity of the bubble contact line, driven by substrate hydrophobicity, that balances the outflux of gas from the bubble apex. Here, we develop an alternate formulation of this mechanism that predicts rich behavior in agreement with recent experimental measurements. Namely, we find that...

A single bubble of air in water can emit pulses of blue-white light that have durations of less than 50 ps while it is oscillating in an acoustic standing wave. The emission is called sonoluminescence. A knowledge of the bubble diameter throughout the cycle, and in particular near the time of sonoluminescence emission, can provide important information about the phenomenon. A new Mie scattering...

In this paper we present a theoretical study of the structure, energetics, potential energy surfaces, and energetic stability of excess electron bubbles in ((4)He)(N) (N=6500-10(6)) clusters. The subsystem of the helium atoms was treated by the density functional method. The density profile was specified by a void (i.e., an empty bubble) at the cluster center, a rising profile towards a constan...

The branching of streamers in high pressure gas discharges and discharges in liquids is an almost universal occurrence having many causes. In this paper, we discuss results of an investigation of one possible cause—inhomogeneities in the media through which the streamer propagates. These inhomogeneities produce corresponding enhancements or decreases in ionization and excitation as the avalanch...

We report experimental data of bubble growth in natural rhyolitic melt with 1.4^2.0 wt% initial total H2O at 0.1 MPa and 500^6003C. Growth of many bubbles is monitored in every experiment. Bubble growth rate increases with temperature and initial total H2O. At a given temperature and initial total H2O, bubble growth rate also increases slightly with bubble size. The average growth rate for bubb...

The pulsating bubble surfactometer (PBS) is often used for in vitro characterization of exogenous lung surfactant replacements and lung surfactant components. However, the commercially available PBS is not able to dynamically track bubble size and shape. The PBS therefore does not account for bubble growth or elliptical bubble shape that frequently occur during device use. More importantly, the...

in present paper, dynamic behavior and control of a fluidized bed reactor for polyethylene production has been considered. a double active sites model for ziegler-natta catalysts is used for simulation of polymerization reaction. hydrodynamic behavior of the bed is modeled using a two phase model including bubble and emulsion phases in which bubble phase has plug flow pattern with differentiall...

oscillation of newly coming bubble is between -90 to 90 degrees. Under this condition, the radius of the aggregated bubbles is determined by the ultrasonic wave frequency and the relative phase. Based on the model, numerical analysis is carried out. The Bjerknes force over (x,y) plane is evaluated for two or more bubbles cases. The stability of a couple of aggregated bubbles is also discussed. ...

A model of formation, development, and acoustic properties of the bubble cloud resulting from an underwater explosion is presented. The model includes several parts: explosion globe dynamics, initial break-up of the explosion globe, turbulence created by the explosion globe fragmentation, and further break-up of the bubbles by the turbulence. The time history of the bubble cloud properties is c...

During bubble or droplet coalescence, there is a puzzling tendency for the coalesced bubble or droplet to be preferentially placed closer to the larger of its two parents. We confirm that this preference is a function of parent size ratio by directly visualizing coalescing air bubbles on an oil-water interface and coalescing water droplets immersed in oil. We find that the final position of the...