As a study to clarify the mechanism of the electrical conductivity of carbon, the, measurements of electric resistance and thermoelectric power are reported this paper, also, involves some description of the recent works on this problem by other authors.
To trace the carbonization process, author choose the phenol-formaldehyde resin and the anthracite as starting material, They were thermally decomposed in hydrogen or other reducing gas, between 550° and 1000°C. Electric measurements were done at the-temperature range from 20° to 350°C.
The results satisfy the intrinsic semiconductive formula, the constants involved varying markedly with the temperature of heat treatment. In this considerable change, the crystallite seems to play the more decisive role than the crystallite boundary. This model. explains some other experiments quoted here.
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