grain (particle) size distribution (rus. гранулометрический состав otherwise распределение по размерам) — size distribution of isolated particles, crystallites, grains of ceramics or other morphological objects, regardless of their chemical composition.

Description

Grain-(particle) size distribution characterises a mixture of particles forming flowing solids, such as soil or ground. Distributions, obtained by particle size analysis, are presented in the form of tables or graphs. The graphs are usually based on cumulative function, i.e. share of particles with sizes below the value on the horizontal axis (the axis of sizes), or particle size distribution obtained by differentiating the cumulative function. Particle size distributions are usually represented as histograms (see Fig.).

Important parameters of the grain size distribution are not only the number and position of the peaks, but also their intensity and width. Such size distribution, in which the width of the only peak is smaller than 10% of its maximum on the size scale, is called monodisperse distribution. Accordingly, the measured object is called “monodisperse object”.

Illustrations

Examples of cumulative curve (line) and particle size distribution curve (histogram). The Q
Examples of cumulative curve (line) and particle size distribution curve (histogram). The Q symbol on the left vertical axis represents the proportion of particles with diameter D that is smaller than diameter on the horizontal axis; the dQ symbol on the right vertical axis represents a relative quantity of particles with the given diameter.

Author

  • Shlyakhtin Oleg A.

Source

  1. Grain size distribution // The Great Soviet Encyclopedia (in Russian). — Moscow.: Sovetskaja ehnciklopedija, 1969–1978. — http://dic.academic.ru/dic.nsf/bse/81171/Granulometricheskijj (reference date: 12.12.2011).

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