FIELD: physics.
SUBSTANCE: invention relates to a method of determining a diffusion coefficient in solid articles from orthotropic capillary-porous materials, comprising forming in the analysed sample a uniform initial content of a solvent distributed in a solid phase, bringing the flat surface of the sample into contact with a solvent dose source, pulse wetting in a given direction of the analysed orthotropic material along a straight line with a constant solvent constant flow source, performing electrodes of a galvanic converter in the form of rectilinear sections and their arrangement on both sides of the pulse humidification line on straight lines parallel to the pulse humidification line and located at the same specified distance from it, measuring the time variation of the EMF of the galvanic converter, wherein pulse exposure is carried out with a solvent dose calculated by formula: 
, where ρ0 is density of analysed sample in dry state; Up is the equilibrium concentration of the solvent in the analysed sample upon contact with saturated solvent vapor at a given temperature; r0 is distance between electrodes of galvanic converter and line of action of solvent dose on surface of controlled article; L is pulse action line length; and time moments τ1 and τ2 is fixed when equal galvanic converter signal values are achieved in vicinity of 0.8 Ep, where E p is electromotive force of galvanic converter at concentration Up.
EFFECT: disclosed is a method of determining diffusion coefficient in solid articles from orthotropic capillary-porous materials.
1 cl, 1 dwg, 1 tbl, 20 ex
