PerkinElmer STA 8000, Инструкция по установке и эксплуатации оборудования

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STA 8000 Hardware . 57
Sample Handling
The STA 8000 measures the change in temperature (relative to a reference) and weight of a
sample as a function of temperature and/or time. The materials and techniques used to
obtain data with an STA 8000 are discussed below.
CAUTION
ATTENTION
Check that the cooling liquid supply is circulating before starting a run.
Vérifiez que l'alimentation en liquide de refroidissement est en circulation
avant de commencer une course.
CAUTION
ATTENTION
Ensure the purge gases are set to the recommended flow rates. A rate
that is too high will disturb the inner furnace lid.
Assurez-vous que les gaz de purge sont réglés sur les débits
recommandés. Un taux trop élevé perturbera le couvercle intérieur du
four.
CAUTION
ATTENTION
Do not open the furnace when it is at an elevated temperature
(>100 °C).
Ne pas ouvrir le four lorsqu'il est à une température élevée (> 100 ° C).
Sample Preparation
The instrument analyzes solid samples in powder, crystal, or granular form. Although
quantitative weight loss accuracy is mostly unaffected by sample shape, the qualitative
appearance of a run may be affected by the sample configuration. The best sample form for
optimum performance is powder or fine granules. Bulk solids can be sliced into small pieces
with a razor or knife. For precise work, such as calibrating the instrument using metal
standards, melting and then cooling the sample in the pan before running the test improves
thermal contact and gives more repeatable results. A sample weight of 10–20 mg is
recommended for most experiments, but the balance can weigh up to 1500 mg, although
this must include the weight of the ceramic pans (approximately 200 mg).
To improve the quality of the data further, cover the sample in a layer of aluminum oxide
(P/N 04190197) within the sample pan. Place a similar quantity inside the reference pan so
that the levels of the material are approximately the same. The aluminum oxide equalizes the
reflectivity of the two pans, which reduces the effect of the sample's surface emissivity on
the heat flow data.
Alternatively, you can place ceramic lids (N520-2032) on to the sample and reference pans to
equalize their reflectivities without the use of the aluminum oxide powder. This approach also
makes it easier to determine the sample weight, because you can measure the empty weight
of the pan and lid before adding the sample.