Determining The Sample Mass - Micromeritics Gemini VII 2390a Operator's Manual

Preparing for Analysis
5. Use rubber gloves to ensure no oils or residue are transferred to the clean tubes and filler rods and
remove the sample tubes and filler rods from the unit.
6. Clean the interior of the sample tubes with the brush supplied with the system.
7. Rinse the sample tubes and filler rods thoroughly with hot water. Then rinse again with isopropyl
alcohol or acetone. If isopropyl alcohol or acetone is not available, deionized water may be used.
8. Stand the sample tubes on the sample tube rack and place the filler rods in a basket or in the rack.
Bake in a vacuum oven for two hours at 110 °C.
9. Remove the sample tubes and filler rods from the oven and allow to cool.
Do not insert the filler rods at this time. Filler rods are inserted just before the sample
tube is installed on the analysis port.
10. Wipe a rubber stopper with a lint-free cloth.
11. Label the sample tube and stopper for identification.

Determining the Sample Mass

Analysis results are expressed in units of surface area per gram of sample; therefore, it is important the
true sample mass be known. The true mass is best calculated as:
• weigh the empty Sample Tube Set (sample tube and stopper or seal frit) before degas
• weigh the Sample Tube Set with sample before degas and subtract the weight of the empty Sample
Tube Set
• weigh the Sample Tube Set with sample after degas and subtract the weight of the empty Sample
Tube Set
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Gemini VII
239-42828-01 - Dec 2012