-----BEGIN PGP SIGNED MESSAGE-----
On Sun, 21 Oct 2001 21:01:40 +0200 (MET DST), Eugene Leitl <[EMAIL PROTECTED]> wrote: >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. At ultrasonic frequencies this can be a problem. At lower freq, generally not. When combined with the electrospray method which provides significant "pull" of the droplet from the nozzle reducing required piezo pressure and consequent cell wall damage. I've not tried it with anthrax but it can work well with ecoli. > >> 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. No, but I have through a micro pipette and if the suspension is dilute (as I noted) it works fine. > >> 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. Indeed. -----BEGIN PGP SIGNATURE----- Version: Hush 2.0 wmAEARECACAFAjvTbecZHGtleXNlci1zb3plQGh1c2htYWlsLmNvbQAKCRAg4ui5IoBV n2XIAJ9zhuCbM1ZXBxNb6veOqN6WpXX1AgCfdGBibYi4UZuqxhR4ueyhwi4sd8I= =4D6c -----END PGP SIGNATURE-----
