Malvern Instruments Spraytec, User Manual

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particle scattering, it is interpreted by the analysis as indicating the presence of
coarse particles.
The only way to overcome this is to eliminate from the analysis the detector
channels affected by beam steering.
An example of beam steering is shown by the following two views:
This spray contains a high concentration of propellant, causing a large scattering
response on the first detector channels. This signal is much larger than the
scattering response seen from the particles within the spray (detectors 30-35). As
such the analysis reports a large particle mode, with only a small volume of fine
particles being present.
There are two ways to overcome beam steering:
.
Move the spray further away from the measurement zone – this can limit
the effect of beam steering in some cases, allowing accurate results to be
obtained.
C H A P T E R 6
S p r a y t e c
P a g e 6 . 2 1
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