The measurement of cohesive force of moist powder was intended in liquid as well as in air. A diametrical compression technique was assumed to achieve the measurement even in liquid comparatively with ease. The suitability of the diametrical compression technique for measuring the cohesive force of moist powder was examined by comparing the cohesive force in air with that measured by a traction table method using moist precipitated calcium carbonate. The cohesive force at the contact point of moist powder bed was determined using the data of calcium carbonate and microcrystalline cellulose obtained by the compression test. In a pendular region of moistening liquid, the cohesive force at the contact point increased with increasing the filling ratio of liquid to the void in powder bed. While in the funicular region, it decreased gradually with increasing the filling ratio, which indicates that the structure of powder bed became heterogeneous due to the formation of agglomerates. This argument was confirmed by observing the resultant failure plane of the moist powder bed at the funicular state brought about by compressing. The above result indicates that the cohesive force measured at the pendular state is the intrinsic value of the primary particle but only apparent at the funicular state. The cohesive of moist bed of precipitated calcium carbonate in carbon tetrachloride was found to be smaller than that in air. This result was explained by the depression of interfacial tension of moistening liquid in carbon tetrachloride compared to that in air.

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Through-flow with fluidized bed drying was devised for purpose of rapid drying of disintegrable materials.
A continuous dryer with 30cm-wide and 150cm-long box type fluidized bed was made for an experiment. Glass beads were used as fluidized particles. The tunnel of the drying position was made of 80 mesh wire net, and a part of it was soaked in the fludized bed and was given a slope.
In this report the measurement of the heat transfer coefficient, h, at the tunnel base and the drying of starch granules used as model material were tried for the purpose of the explanation of the drying mechanism.
At the tunnel base air velocity into the tunnel and the value of h gradually increased at the entrance side. The effect of fluidizing air velocity on h showed characteristic similer to wall-to-bed heat transfer. But h show a low value as a whole.
The drying of starch granules showed satisfactory results and dried granules were obtained without disintegration. The drying rate of granules increased with increasing fluidized bed height.

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Distributions of the number of interparticle contact points and the contact force of granular materials are analyzed by means of the principle of virtual work. The expressions of these microscopic distributions are given in terms of observable macroscopic quantities.

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