水蒸気圧勾配および拡散係数の測定
1956 年 25 巻 4 号 p. 144-149
詳細
1956 年 25 巻 4 号 p. 144-149
The humidity distribution close to the surface of water, soil and some leaves is observed by using a small electric resistance hygrometer and a thermistor thermometer, the former having newly been developed by Prof. K. Shiba and the author. In each case, a region of linear gradient of water-vapour pressure is found, which is considered as a diffusion layer.
The diffusion coefficient is determined from the data of gradient of water-vapour pressure and the rate of evaporation of water in a vessel. The value obtained is 0.239 cm2/s at a mean temperature of 14.8°C and a mean atmospheric pressure of 767mmHg.
The rate of evaporation of water from some leaves is calculated by the observed water-vapour pressure gradients with the value of diffusion coefficient.
The results are tabulated.
