Homogenisation of fluids

The homogeneity of solutions and gas mixtures is also easy to maintain or to reconstitute. The vast majority of calibration CRMs are pure solid substances or solutions. The only difficulty encountered by the manufacturer is the availability of adapted preparation tanks in which large volumes of solutions can be handled, with sufficient stirring capabilities, and without any risk of contamination. Emulsions need to be stabilised through adequate addition of emulsifiers or dispersion products. Such additives may pose the problem of representativeness of the final material. 

The preparation of mixtures of solids e.g. for producing metallic targets or powder pellets, relies mainly on the availability of proper balances and mixers. 

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