This paper investigates the permeability of several multi-layered, woven filter media using air, water and bubble point methods. Estimated filter efficiencies from the bubble point measurements were then compared to a new sonic challenge test method where precision microspheres are fluidised through the pores. Inconsistencies in the bubble point filter efficiencies were found to be dependent on...

AIMS The long-term results of office-based pneumatic retinopexy (PR) using only filtered air were evaluated in a case series of rhegmatogenous retinal detachments with more than 3 years of follow-up, on average. METHODS 77 cases of primary rhegmatogenous retinal detachments arising from superior tears (mean=1.6 tears) were treated with cryopexy (n=61) or laser (next day, n=16) and intravitrea...

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...

[1] The bubble cloud depth and its correlation with extreme winds are key elements of bubble‐mediated gas injection, which are critical to the determination of the global gas budgets. The characteristics of bubble cloud depth were examined frommeasurements collected during the passage of a category‐4 hurricane with winds up to 50 m s. The bubble cloud depth increases linearly with wind speed fo...

In single-bubble sonoluminescence, repeated brief flashes of light are produced in a gas bubble strongly driven by a periodic acoustic field. A startling hypothesis has been made by Lohse and co-workers [Phys. Rev. Lett. 78, 1359 (1997)] that the non-noble gases in an air bubble undergo chemical reaction into soluble products, leaving only argon. In the present work, this dissociation hypothesi...

We report on the influence of submerged bubble clouds on the remote sensing properties of water. We show that the optical effect of bubbles on radiative transfer and on the estimate of the ocean color is significant. We present a global map of the volume fraction of air in water derived from daily wind speed data. This map, together with the parameterization of the microphysical properties, sho...

Dynamic forces between a 50 microm radius bubble driven towards and from a mica plate using an atomic force microscope in electrolyte and in surfactant exhibit different hydrodynamic boundary conditions at the bubble surface. In added surfactant, the forces are consistent with the no-slip boundary condition at the mica and bubble surfaces. With no surfactant, a new boundary condition that accou...

A sonoluminescing bubble has been modeled as a thermally conducting, partially ionized, two-component plasma. The model shows that the measured picosecond pulse widths are due to electron conduction and the rapidly changing opacity of the plasma and that these mechanisms are also responsible for the absence of an “afterglow” subsequent to the sonoluminescence flash while the hot bubble expands ...

The multiple scattering of light by aqueous foams is systematically studied as a function of wavelength, bubble size, and liquid fraction. Results are analyzed in terms of the transport mean free path of the photons and an extrapolation length ratio for the diffuse photon concentration field. The wavelength dependence is minimal and may be attributed entirely to the wavelength dependence of the...

Gas ratios in air withdrawn from polar firn (snowpack) show systematic enrichments of Ne/N2, O2/N2 and Ar/N2, in the firn–ice transition region where bubbles are closing off. Air from the bubbles in polar ice is correspondingly depleted in these ratios, after accounting for gravitational effects. Gas in the bubbles becomes fractionated during the process of bubble close-off and fractionation ma...