On Thu, 18 Oct 2001 [EMAIL PROTECTED] wrote: > A specialized ultrasonic device is not required to produce micron fine > aerosol powders. All one needs is a used and cleaned print head
In fact not, pressure waves strong enough to aerosol liquid will also cause cavitation, resulting in heating and destruction of material. > assembly and its piezo pulse circuitry. Nozzle apertures are > typically 25-50 micron and if the material is suspended, in weak Ever tried pushing a bacterial suspension through a printer head (processivity set aside)? It will clog it up in no time. > concentration, in a solution which quickly evaporates but doesn't harm > the spores it should produce moderate quantities of fine powder > quickly. Um, why don't we quit armchair microbiology, and stick to what we can best: produce lots of uninformed speculations? Oh. > If smaller sizes are desired a field ring charged to 1000-3000v DC can > be placed around and in front of the nozzles. If operated in sync > with the nozzle pulses it can cause a the emerging droplets to cascade > to nanometer size via the electrospray effect (now becoming common in > drug production). See > http://www.essex.ac.uk/bs/staff/colbeck/index.htm#appas I think it should be easy enough to look up relevant patents online, assuming one is bored enough.