Description and Study of the Moisans Method

There is a kind of recognition when a method is associated with the surname of its author. 

The apparatus described [37] looks very simple, however it is efficient, at least at first glance. It consists of two parts pressed together under a pressure around 5 kg/cm.  

A sheet of a polymer (0.1-0.15 cm) thick containing up to 2-10% of a diffusing substance is used as the source. The polymer through which the substance should diffuse is made of more than 20 thin films, 0.006 cm thick for each, pressed together, giving a kind of thick sheet. 

The concentration of the diffusing substance is very high in the source, so that the saturation could be attained in the polymer film in contact with it. 

The two parts of the system, e.g., the source and the packed polymer films, are considered as two semi-infinite media. Moreover, because of the very high concentration of the diffnsing substance in the source, the surface of the first film in contact with the source is saturated, with a concentration denoted as S. The equation expressing the profile of concentration of the diffusing substance developed with time through the source is  

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