Malvern Instruments Spraytec, User Manual

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The available views are:
.
Particle Size Distribution – this is the left-hand view in the above exam-
ple. It shows a histogram and a cumulative “percent volume smaller than”
line. A table of values is shown below the graph. This view is described in
detail in Chapter 6.
.
Derived Parameters – displays a table of values for each parameter ana-
lysed. This view is described in detail in Chapter 6.
.
Measurement Parameters – gives textual information on the way the in-
strument is set up. This view is described in detail in Chapter 6.
.
Corrected Light Scattering – this is the right-hand view in the above ex-
ample. The first bar in the histogram shows the transmission signal (laser
intensity) plotted against the left-hand Y axis. The remaining bars show the
scattering signal for each detector (plotted against the right-hand Y axis).
The scattering signal for each detector is shown in a table beneath the
graph. The curve is the fitted curve for the chosen optical model. This re-
lates to the calculated result and the residual value.
.
Raw Light Scattering – the scattered light received by each detector, be-
fore the removal of noise. The table shown below the graphic includes a
Monitor value , giving the laser intensity measured at the Transmitter.
.
Dark Background – also called the electronic background, this is the
background with the shutter closed. This table also includes a Monitor
value.
.
Light Background – also called the optical background, this is the back-
ground with the shutter open. This table also includes a Monitor value .
'
N o t e
. Excessive dirt on the optics yields high background signals and degrades
the instrument’s sensitivity. See Chapter 8 for instructions on cleaning
the windows and advice on how to keep the windows clean for an
acceptable amount of time.
Display settings
Right-click in a record view and select Properties to change its settings. The
dialogue differs depending upon the view selected, as described below.
For Particle Size Distribution and overlay views, the following can be changed:
.
The style and limits for both the X and Y axes.
.
The length of the X axis. Enter minimum and maximum particle sizes,
then enter these limits in
m
m or in mesh sizes (select the Use Mesh check
box). On clicking the Use Mesh check box, the Minimum Size and Maxi-
mum Size fields are automatically converted between
m
m and mesh values.
C H A P T E R 4
S p r a y t e c
P a g e 4 . 9