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Influence of crucible

During the TGA measurement, crucibles must of course be open to the atmosphere. It can be important, however, to seal the sample hermetically first, before the actual measurement is performed in order to prevent it from coming into contact with air. The lid of the crucible is then pierced immediately before the start of the measurement (e.g. in the sample changer). [Pg.94]

Reactions in the gas phase proceed more rapidly in completely open crucibles than in a so-called self-generated atmosphere. In a sealed crucible with a very small hole in the lid, or in a crucible with a lid without a hole placed loosely over the sample, the weight loss is shifted to a higher temperature. [Pg.94]

The material of which the crucible is made must not influence the reaction of the sample. In general, alumina (aluminium oxide) crucibles are used for TGA measurements. These [Pg.94]

Platinum crucibles have the advantage of good thermal conductivity, which improves DTA performance. Finally, platinum is not always inert. It has a catalytic effect and can, for example, promote combustion reactions. This is also discussed in Section 10.3.2. [Pg.95]

Damage to platinum crucibles due to alloy formation with metal samples can be prevented by covering the bottom of the crucible with a very thin layer of a-aluminium oxide powder before inserting the metal sample. [Pg.95]


The author carried out calculations to investigate the m-c interface shapes with cylindrical and square crucibles and to investigate the influence of crucible shape on m-c interface shape using 2D and 3D global analyses. [Pg.65]

As a first example, the influence of crucible and crucible support tolerances is analyzed for VGF using the CRYSVUN-3.0.07 code that includes heat conduction, radiation, latent heat but not convection in the melt and the gas phase. For the... [Pg.241]


See other pages where Influence of crucible is mentioned: [Pg.87]    [Pg.94]   


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