Micromeritics AccuPyc 2 1340, Руководство оператора

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Preparing for Analysis AccuPyc II 1340
4-2 June 2013
Entering Analysis and Report Parameters
Enter appropriate analysis and report parameters for the current analysis. Refer to Set Up ,
page 3-11 and follow the instructions given for the prompts. The parameters you specify or
choose in Set Up determine what prompts and information are displayed for the analysis.
If you plan to have data results e-mailed automatically after analysis, be sure to specify e-mail
parameters:
• Request E-mail report, refer to page 3-15
• Specify E-mail address and server, refer to page 3-20
Preparing and Loading a Sample
It is important to prepare your sample properly to obtain accurate results. Samples must be free
of moisture in order to obtain true sample mass and to avoid the distorting effect of water
vapor on the volume measurement. The following procedures are recommended; however,
modifications may be necessary for some materials.
• Heat-sensitive materials may have to be dried by long-time exposure to silica gel, freeze
drying, etc.
• Materials having a low melting point may be dried using the purge process. In this case,
do not weigh the sample and cup until after the purge and analysis have been completed.
The important thing to remember is to avoid exposure of the dried sample to atmospheric
moisture during each step of the preparation process. This means weighing as rapidly as possi-
ble and installing in the instrument without unnecessary delay.
1. Weigh the empty sample cup. (If volume only is to be measured, you may skip this step).
2. Place a quantity of sample in the cup. Use as large a quantity of sample as possible; we
recommend that the cup be at least two-thirds full. Pack powders and fluffy materials (if
permissible) to obtain maximum sample weight in the cup. (Refer to
ORDERING
INFORMATION , page 6-1 to order specially designed cups for powders and fluffy
materials.)
3. Place the sample cup (with sample) in a drying oven. The amount of time the sample
must be heated depends on the material and the temperature it will tolerate; this may have
to be established by other tests.
4. Remove the sample cup from the oven and transfer it to a desiccator provided with active
desiccant. Allow it to cool until near room temperature. In the steps which follow,
minimize air exposure of the sample.
Keep the cap on the sample chamber except when actually inserting or removing a
sample. When the chamber is left uncapped, water vapor adsorbs on the inner surface
of the chamber and temperature instability may occur; either condition can affect
analysis results.