MSP120, 122, and 125- MOUDI-II & NanoMOUDI-II

MOUDI-II™and NanoMOUDI-II ™ 10- and 13-stage Micro-Orifice Uniform-Deposit Impactors with internal stepper-motor stage rotation to provide uniform particle deposits and high accuracy aerosol sampling from 10 nm to 10,000 nm for collecting sizefractionated particle samples for gravimetric and/or chemical analyses


MOUDI-II™ and NanoMOUDI-II™ are second generation MOUDI™ and NanoMOUDI™ impactors. Both series of impactors are precise, and high accuracy devices designed for sampling and size-fractionation of airborne particles for gravimetric and/or chemical analysis. The primary difference is the use of internal embedded stepper motors to rotate the impaction plates by the second generation MOUDI-II™ series and the use of
external mechanical gear rotation in the original MOUDI™.
Both series of the MOUDI™ impactors are referred to as Micro-Orifice Uniform Deposit  Impactors,
since they use micro-orifice nozzles for jet acceleration, and are available with the uniformdeposit feature by rotating the impaction plates with respect to  the nozzles to spread out the particle deposit uniformly on the collection substrates. The uniform deposit prevents heavy particle build-up under each nozzle to reduce particle bounce and blow-off that may otherwise occur. The micro-orifice nozzles used in these impactors reduce the jet velocity, pressure drop, particle bounce, and evaporative loss. Up to 2,000 microorifice nozzles as small as 50μm in diameter are used.
The original MOUDI™ series of impactors are noted for their superior aerodynamic design, sharp cut-size characteristics and low inter-stage particle losses. These features, together with their accurate cut-size calibration, have made the MOUDI™ the impactor of choice for high quality environmental research. The same characteristics are retained in the MOUDI-II™ series of impactors.