Radulescu Gasdynamics Laboratory

Geoff Maines was instrumental in our efforts to characterize thermites for use in cellular injury studies.  His work addressed the underwater shock performance of ball-milled activated thermites and the ability to control the pressure pulse amplitude and widths.   He has now graduated with a MASc degree from our group - unfortunately someone else will benefit in the future from his enthusiasm for research, ambition and meticulousness in setting up experiments.  Ongoing work with Kadeem Dennis studies the interaction of these pressure waves with cells.  Geoff's thesis:  Underwater Pressure Pulses Generated by Mechanically Alloyed Intermolecular Composites Recently, the use of thermite-based pressure waves for applications in cellular transfection and drug delivery have shown significant improvements over previous technologies. In the present study, a new technique for producing thermite-generated pressure pulses using fully-dense nano-scale therm...

The key question in detonation research is being able to predict limits. How easy is it to initiate a detonation? What are the limits of propagation in the presence of attenuating boundary conditions? Most models developed over the past decades rely on one-dimensional formulations - resulting in simple models. Nevertheless, detonations in reality are plagued by instability, which takes the form of cellular structures in gases and localized heterogeneities involving hot spots in condensed media. The question that arises, is what role do these non-homogeneities have on the limits of detonations ? A very recent study from Li, Mi and Higgins tackles this central issue in detonation science. By introducing non-heterogeneities in their explosive medium, they find that the detonation limits become wider. Localized unsteady effects sensitize the propagation of detonations. The problem they address is the detonation propagation in a unconfined charge, the so-called critical tube pr...