Horiba Scientific Quanta-phi F-3029, Руководство по эксплуатации

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Quanta-
φ
rev. C (23 Apr 2010) Theory of Operation
1-10
the main chromophore’s concentration systematically to evaluate the self-absorbance
properties of the emission. In powder samples, for instance, pulverize and homogenize
the chromophoric sample with a non-luminescent powder such as barium sulfate, in or-
der to dilute the solid. The principle is similar to that for liquids, in that the sample is
diluted to vary and minimize self-absorption at the surface. The solid dilution also
serves to dilute the chromophoric sample to the point where its light-scattering proper-
ties are primarily determined by the surrounding non-luminescent powder. This is im-
portant because non-luminescent powder—when similarly pulverized and homoge-
nized—may be used as the blank sample. In powder measurements, homogenization of
the particle-size and light-scattering properties (that is, matching the sample and blank)
is vital to acquiring precise and accurate values for
υ
.