ベーマイト構造をもつAl_1-xCrxOOH系固溶体を熱水条件下で得た. Crの置換度xの関数として格子定数a, b, cを測定し, 赤外線スペクトル, 可視部吸収スペクトルを解析した. Crの置換度が増えるとCr-Oの距離と電子間反撥エネルギーを示すRacahパラメータBが大きくなり, 配位子場パラメータΔは小さくなる. O-H…O結合は固溶体の生成によりほどんど変化を受けなかった.

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Temperature dependences of Young's modulus and internal friction of polycrystalline nickel-zinc and manganese ferrites were measured with sonic resonance technique. The effects of porosity of ferrite and small quantity of additives to ferrite on the temperature dependences were also examened. Exfoliation of grain particles from a polycrystalline ferrite was discussed with respect to the internal friction of the grain boundary. The results were as follows.
1) Young's moduli of nickel-zinc and manganese ferrites were measured in the temperature range from room temperature to about 1100°C. The temperature dependence of Young's moduli showed a discontinuous change in the vicinity of Curie temperature in both nickel-zinc and manganese ferrites.
2) In the temperature dependence curve of internal friction of nickel-zinc ferrite, large internal friction which must have resulted from anelasticity of grain boundary was observed. This large internal friction increased with increasing temperature without showing any maximum point.
3) The temperature in which internal friction resulting from anelasticity of grain boundary appears, shifted to lower with larger porosity in nickel-zinc ferrite.
4) The temperature dependence curve of internal friction of manganese ferrite showed a maximum in the vicinity of 700°C. This maximum is reasonably attributed to anelasticity of grain boundary, but not to the precipitated α-Fe₂O₃ on grain boundaries.
5) Small quantity of some additives to manganese ferrite effected on the magnitude of internal friction and the temperature in which internal friction showed its maximum. The addition of small quantity of SiO₂ to manganese ferrite decreased the internal friction and shifted the maximum temperature of internal friction to higher temperature side. And the manganese ferrite with small quantity of SiO₂ showed little exfoliation of grain particles from the mother polycrystalline ferrite when the ferrite was rubbed with γ-Fe₂O₃ magnetic tape.

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Surface features observed on the basal pinacoids of SiC crystals which are infered to thermal etching are described. These include concentric depressions, wave-shaped hills, depression spirals and others.
Both growth and etch features are observed on the same face, suggesting that growth and dissolution take place simultaneously on the same face and crystal.
Distinct differences in the characteristics of these features are noted between the (00.1) and (00.1) faces. It is also observed that the characteristics of thermal etch patterns vary progressively with the increase of undersaturation.
To trace the process of thermal etching, crystals are thermally etched and their surface features are compared with their original features as well as with that of as-grown crystals.

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それぞれ異なったdiscrete ionに結合している2つの非架橋酸素と, 2つのナトリウムよりなるモデルを用いて, ナトリウムに介存された非架橋酸素間の相互作用を簡単なSCF理論を用いて求めた. その結果, 4原子系内に作られる相互作用軌道の結合性および電子密度が求められた. 同様な手法を用いて, 2つの非架橋酸素が無限に離れた場合の状態を求めた. 求められた結果から前報でガラス変態を生ずるに重要な役割をはたした非架橋酸素間の有効ポテンシャルが求められた. このポテンシャルの観点よりガラスの準平衡状態について簡単に議論した.

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The hydration of calcium sulfate hemihydrate is studied mainly by the conduction calorimeter. The hydration process can be explaind by dissolution and recrystallization as follows; calcium sulfate hemihydrate dissolves into liquid phase and the nuclei of calcium sulfate dehydrate appear and grow into crystallites. As ‘gypsum gel’ is not found, the topochemical reaction is not considered to occur in the hydration of calcium sulfate hemihydrate.
A small amount of calcium sulfate dihydrate is produced on the grain surface of plaster of Paris when it is exposed to moist air. The dehydrates thus produced play a very important role in the hydration process, because it acts as the nuclei. β hemihydrate has larger specific surface area, and dissolves faster than α hemihydrate. However, the production of dihydrate on the surface is retarded by the soluble anhydrite exist in the sample. Accordingly, induction period is, sometimes, longer than that of α hemihydrate.

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Photosensitive glass containing Ce and Ag was studied by ESR measurement after γ-irradiation at 77°K. At first no Ag⁺⁺ was formed, but after 120°-200°C thermal treatment, Ag⁺⁺ was formed and both hole and electron centers decreased. After 400°C thermal treatment Ag⁺⁺ decreased and hole center was not observed and Ag colloid formation increased. Consequently, tentatively proposed mechanism of Ag colloid formation is nucleation and growth of supersaturated Ag⁰ centers via Ag⁰ diffusion and does not assume the predetermined condensation site of Ag⁰.

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