Sample cups are assembled as follows:
8.6.1.
Place the white polypropylene inner ring, with leading edge toward the top on a
8.6.1.1.
clean, flat surface.
Position the window support tool around the inner ring.
8.6.1.2.
Lay a piece of window material over the support tool so that the material is flat at
8.6.1.3.
the rim of the inner ring.
Push the polypropylene outer ring vertically down onto the inner ring. If
8.6.1.4.
necessary use the assembly tool to help push the outer ring down.
When assembling a sample cup or secondary window it is important to use a clean
8.6.1.
piece of window material.
Always visually inspect the assembled cell for leakages when filled with liquid.
8.6.2.
Always replace the window material if it is creased or wrinkled.
8.6.3.
Plastic sample cups are disposable after use.
8.6.4.
(IMPORTANT) NEVER LEAVE A SAMPLE CUP FILLED WITH LIQUID IN THE
INSTRUMENT SAMPLE PORT AFTER COMPLETION OF A MEASUREMENT.
Use a sample cup lid for volatile samples such as gasoline to reduce evaporation.
8.6.5.
Evaporation usually results in a change in composition of the sample, which may lead
to incorrect results.
8.7.
Filling Sample Cups
To measure elements below calcium in the periodic table a minimum sample depth of
8.7.1.
2-3mm is sufficient
For heavier elements, fill the cups to the line in the interior of the sample cup to ensure
8.7.2.
a constant volume.
8.8.
Testing for Sample Preparation Errors
To test for instrument precision, place a sample of material into the instrument and
8.8.1.
analyze it ten times in a row without removing it from the instrument. Calculate the
standard deviation of these measurements for the instrument repeatability (precision).
To test for sample presentation error, place a sample of material into the instrument
8.8.2.
and analyze it ten times in a row, removing it from the instrument and replacing it back
into the sample port for each analysis. Calculate the standard deviation of these
measurements for the error introduced by sample presentation.
To test for sample preparation error, prepare ten identical samples of the same material
8.8.3.
using the intended sample preparation procedure. Analyze all ten samples in a row.
Calculate the standard deviation of these measurements for the error introduced by
sample preparation.
To test for sample thickness error, analyze a sample, then double the thickness of the
8.8.4.
sample by either stacking an identical solid sample on it, or increasing the depth of the
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