The effect of positive and negative pressure on the modes of oscillation of a multielectron bubble in liquid helium is calculated. Already at low pressures of the order of 10-100 mbar, these effects are found to significantly modify the frequencies of oscillation of the bubble. Stabilization of the bubble is shown to occur in the presence of a small negative pressure, which expands the bubble r...

In the parameter region for sonoluminescence of a single levitated bubble in a water-filled resonator it is observed that the bubble may have an enormous spatial stability leaving it "pinned" in the fluid and allowing it to emit light pulses of picosecond accuracy. We report here observations of a complex harmonic structure in the acoustic field surrounding a sonoluminescing bubble. We show tha...

The evolution of an axi-symmetric Stokes bubble is considered when the bubble volume is changed. Linear stability analysis shows that an expanding spherical bubble is stable, while a shrinking spherical bubble is unstable. Numerical calculations of the time evolution shows that for certain initial condition, such a bubble can form cusps or near cusps or undergo topological change (pinching) bef...

Cyclooctatetraene (COT), the first 4nπ-electron system to be studied, adopts an inherently nonplanar tub-shaped geometry of D2d symmetry with alternating single and double bonds, and hence behaves as a nonaromatic polyene rather than an antiaromatic compound. Recently, however, considerable 8π-antiaromatic paratropicity has been shown to be generated in planar COT rings even with the bond alter...

The typical bathtub curve and its “standard”shape have been widely accepted as an engineering tool in reliability management and training. However, some recent researches reveal that the typical theory of ‘bathtub curve’is not so convincing in some situations. Therefore, a critical discussion is developed to research the bath-tub curve along three significant periods of bath-tub; i.e. infant mo...

We study the effect on bubble motion of the sudden streamwise expansion of a liquid-filled tube of square cross-section, which is formed by a pair of backward-facing and forward-facing steps. When a bubble of finite volume traveling under constant volume flux reaches the backward-facing step that marks the start of the expansion, the extent to which it broadens to partially fill the expansion d...

foam injection is widely applied in amounts of fields to drilling, production, and formation protection. sometimes, the application result is disappointing, which is caused by the failure of bubble generation in foam flooding. therefore, it is necessary to seek ways for improving the performance of foam injection. an increased disturbance to the stratum, like the vibration caused by a seismic o...

1. Anonymous, Towels beat hot air driers hands down. Associated Press Newswire, 1993(July). Handwashing Michaels. Reports on a study done by the University of Westminster and financed by the Association of Soft Tissue Paper Manufacturers finding that hot air dryers increased bacteria on hands more than 500%. 2. Anonymous, Alcohol for hand hygiene: New comparative studies add to the evidence bas...