A series of compression tests have been carried out with silica sands put in a square box (300mm×300mm×270mm) compressed with a shorter punch (180mm×300mm). The distributions of the pressure and the friction stress on the inner surface of the box, the internal stress, the deformation and the strain in the box, and the relationship between the load and the displacement of punch have been measured by using the pressure cells, the friction cells and the internal stress cells developed by the authors. The following conclusions have been obtained:
(1) The pressure distribution shows the maximum values at the centers and the minimum at the ends below the lower surface of punch and on the bottom of the box. The maximum values are 1.67 and 1.19 times as great as the mean pressure below the lower surface of punch, respectively. Rounded corners of the punch scarcely affect the pressure distribution. The hysterisis effect of decreasing pressure in unloading is small.
(2) The maximum friction stresses occur at about 1/3 and 1/4 on the way from the centers to the ends below the lower surface of punch and on the bottom of box, respectively. Those are 0.42 and 0.29 times as great as the mean pressure below the lower surface of punch.
(3) The flows of principal stresses coincide well with those of principal strains.
(4) Slip-lines occur one by one at the intervals of increase of the mean pressure of punch by 10kgf/cm² along the characteristics of stresses at the lowest place where the grains are pushed up because of the shearing stress exceeding the limit of the friction stress.
(5) The displacement of punch increases in proportion to the load.

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A fundamental equation is presented for predicting the compaction behavior of flocculated suspensions.
It is assumed that the porosity of flocculated material is uniquly determined by the effective (interparticle) pressure and that the permiability of slurry is a function of both porosity and the mean diameter of particles of which flocs are made up. In deriving the fundamental equation, the material and the momentum balance of solid phase and of liquid phase are respectively considerd together with above two assumptions. An analogy between floc-compression and soil consolidation is presented in this study.
Sedimentation of flocculated suspensions of initially uiform concentration is also studied experimentally. The numerical solutions of this fundamental equation are in good agreement with the experimental results.

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ハロゲン化アルカリの中から吸着機構の互いに異なるKCl, KBrを試料として用い, 水蒸気吸着をくり返えし行なわせ, その吸着性変化について検討した結果, 以下の点が明らかにされた。
(1) ハロゲン化アルカリ表面の水のような極性の物質を吸着させると, 固体表面上のイオンの相対的位置は, 水蒸気吸着に好都合なように変化する。この変化はハロゲン化アルカリ表面層の数分子層に順次伝達されるので, 完全な吸着平衡には時間を要する。またこれは吸着等温線のヒステリシス発生の一因と考えられる。
(2) KClの場合, 高圧側に認められるステップを境にして, 吸着水分子による表面状態の変化機構は異なることがわかった。低圧側のそれは表面イオン配置の相対的変位であり, 一方高圧側のそれは水和イオンの形成にもとつく表面積変化である。
(3) 表面を動きうる水和イオンの形成のためには, 吸着水分子同士の横方向の連続的な接触が必要である。
(4) このような系において吸着平衡の決定は難かしく, 吸着熱, 吸着エントロピーの算出には注意を要する。

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