Determine The Sample Mass - Micromeritics TriStar II 3020 Installation Instructions And Checklist

D
ETERMINE THE
See also:
Sample Data Worksheet on page B - 2
Clean, dry sample tubes are essential for accurate results. How much sample to use can be
determined best by experiment. In general, a sample providing 40 to 120 square meters of total
surface area is recommended for nitrogen analysis. Less than 40 square meters may cause
unreliable results. More than 120 square meters will extend analysis time.
Smaller quantities are required for samples having high surface areas. These samples require
careful weighing after degassing because a small error may represent a considerable percent of
total weight. Proper weighing techniques are most important in this case. Use no less than 100 mg to
reduce the effect of weighing errors.
Care should be taken when loading powders; the accessory funnel is useful for this purpose. Large
granules or chunks may be loaded with forceps.
Analysis results are expressed in units of surface area per gram of sample; therefore, it is important
the true sample mass be known.
Follow the instructions on the Sample Data Worksheet and complete all fields to find the true sample
mass.
1. Record the Sample Tube Identification on the Sample Data Worksheet.
2. Tare the balance and allow it to stabilize at zero.
3. Place the empty sample tube set on the balance.
4. Record the stabilized mass on the Sample Data Worksheet as [A] Mass for empty sample
tube set. Remove the sample tube set from the balance.
Do not touch the sample with bare hands while performing the following steps. Doing so
could affect the accuracy of results.
5. Place a sample container on the balance. Tare the balance and allow it to stabilize to zero (0).
6. Slowly pour the specified amount of sample into the sample container.
7. Remove the rubber stopper, seal frit, or TranSeal from the sample tube.
8. Use the sample tube funnel (provided in the accessories kit) and pour the sample from the
weighing container into the sample tube.
TriStar II 3020 Confirm Installation Instructions and Checklist
302-42870-04 (Rev A) — Sep 2017
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AMPLE ASS

Determine the Sample Mass

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