Possible mechanical and hydraulic costs to increased cavitation resistance were examined among six co-occurring species of chaparral shrubs in southern California. We measured cavitation resistance (xylem pressure at 50% loss of hydraulic conductivity), seasonal low pressure potential (P(min)), xylem conductive efficiency (specific conductivity), mechanical strength of stems (modulus of elastic...

In this paper we present a mathematical model for estimate the collapse time of a gas bubble in a vane of a oil gerotor pump. This amount of time cannot be greater of the total time spent by the pump for filling and then emptying out a vane in a single revolution, otherwise there is a loss of lubrication between internal and external gears. We assume that oil is incompressible and viscous, the ...

1. Introduction One of the most important recent applications of sonochemistry has been to the synthesis and modification of inorganic materials [1-5]. In liquids irradiated with high intensity ultrasound, acoustic cavitation drives bubble collapse producing intense local heating, high pressures, and very short lifetimes; these transient, localized hot spots drive high energy chemical reactions...

This paper demonstrates a new method to porate single suspension living cell membrane using cavitation bubble-induced high speed jet flow. A microfluidic chip with an array of single cell trapping structures is designed and fabricated to trap sing cell and induce the asymmetric collapse of the cavitation bubble. Myeloma cells suspended in Trypan blue saline solution is tested and single Myeloma...

Recently Ceccio and Brennen [1][2][3] have examined the interaction between individual traveling cavitation bubbles and the structure of the boundary layer and flow field in which the bubble is growing and collapsing. They were able to show that individual bubbles are often fissioned by the fluid shear and that this process can significantly effect the acoustic signal produced by the collapse. ...

Bubble cavitation is one of the major mechanisms for ultrasound-induced bioeffects. Characterising the bubble dynamics, expansion and collapse, is of importance in understanding the cavitation phenomenon and estimating the consequent outcome. In this study, Doppler ultrasound method was firstly used to measure the bubble wall velocity. Bubbles were generated in water using a beam of high-intens...

One of the causes of the breakdown of the mechanical heart valves (MHVs) is cavitation. A reliable in vitro test method to evaluate the cavitation potential has to be developed for the patients’ safety. It is the bubble implosion that damages the materials, thus observing the cavity implosion behavior is essential. According to sonoluminescence, the collapsing cavitation bubbles emit the faint ...

Cavitation bubbles were generated by the 193 nm argon fluoride excimer laser delivered with a specially designed tip into absorbing NaCl solution. The dynamics of bubble formation and collapse have been studied using fast flash photomicrography. The bubble dimensions were measured at different time delays as a function of the tip exit diameter, the energy fluence of the laser, and the NaCl conc...

Rupture of small blood vessels is a primary feature of the tissue injury associated with shock wave lithotripsy (SWL), and cavitation has been implicated as a potential mechanism. To improve our understanding of the damage mechanism, dynamics of SWL-induced bubbles in constrained media were investigated. Silicone tubing and cellulose hollow fibers (i.d.=0.2 ~ 1.5 mm) were used to fabricate vess...

The spatiotemporal dynamics of cavitation bubble growth and collapse in shock-wave lithotripsy in a free field was studied experimentally. The lithotripter was equipped with two independently triggerable layers of piezoceramics. The front and back layers generated positive pressure amplitudes of 30 MPa and 15 MPa, respectively, and -10 MPa negative amplitude. The time interval between the launc...