2008 MAR 31 - (VerticalNews.com) -- According to recent research from Ottawa, Canada, "Monodisperse aerosol deposition in an idealized mouth geometry with a dry powder inhaler (DPI) mouthpiece inlet is studied numerically using a standard Large Eddy Simulation (LES)."

  "A steady inhalation flow rate of Q = 90 L/min is used. Ten thousand of particles (4.1 mu m diameter and 953.0 kg/m(3) density) are released individually in the computational domain and aerosol deposition is determined," wrote M. Ilie and colleagues, Carleton University ...read more

  2008 MAR 31 - (VerticalNews.com) -- "A new instrument to study ice nucleation, the Zurich Ice Nucleation Chamber (ZINC), has been constructed. It is a continuous flow diffusion chamber following the design by Rogers (1988) but has a flat parallel plate geometry," scientists writing in the journal Aerosol Science and Technology report.

  "The instrument can operate at temperatures as low as 236 K with the current setup with ice supersaturations of up to 50%. The typical sample flow is 1 lpm with a total flow of 10 lpm using twice 4.5 lpm for sheath flows. FLUENT simulations were performed and are presented to discuss the flow, temperature, and humidity profiles within the main chamber. Activation experiments with silver iodide particles were used to validate the instrument against literature data. We report the onset of freezing for an activated fraction of 2% of all particles," wrote O. Stetzer and colleagues ...read more

  2008 FEB 18 - (VerticalNews.com) -- According to a study from Madrid, Spain, "This paper presents the results of an experimental investigation on the deposition of multiply charged particles on wire screens by the combined mechanisms of diffusion and image force. Experiments were performed with particles having diameters between 25 and 65 nrn (transition regime), carrying 0, + 1, +2 or +3 elementary charges, and using three different flow rates, two types of wire screen, and two types of test aerosol. ...read more