It is endeavored to confirm the mineral composition of Soma Ohori clay, and also to understand its utilization towards porcelain manufactories. Therefore, this study does not intend to pursue respectively the charateristic of mineral composition. The experimental methods employed in this study are as follows: microscopic observation, X-ray diffraction method, infra-red absorption analysis, quantitative chemical analysis.
Summarizing these experimental data, Ohori clay is originated in sedimentary rocks (tuff), and it is composed of clay minerals produced by its transition process towards soil. This olayish soil cotains various clay minerals such as montmorillonite and kaolinite.

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In this study on the carbonation of calcium hydroxide, some fundamental problems in the carbonation of hydrated cement were discussed, and distinctive features in the carbonation of calcium hydroxide were examined. Several species of calcium hydroxide were carbonated with CO₂ gas at a poor coexistence of water (gas reaction), or at a rich coexistence of water (liquid reaction) and examined for a rate of carbonation and for a crystallinity of calcium carbonate in the reacted layer. The results obtained are as follows:
1) A rate equation of the solid state reaction presented in this study has several advantages; the equation can apply to rates of different processes successfully, and the value of n in the equation indicates the rate determing process quantitatively.
2) Rates of the carbonation are differed in the gas reaction and in the liquid reaction. The water quantity coexisting in the reaction influences the crystallinity of calcium carbontae, resulting the porosity difference of reacted layer of specimens.
3) Reactivity of species of calcium hydroxide depends on preparing condition and crystallinity of species, and determine the rate of reaction and species of products.
4) The results on the rate equation and on the difference between gas reaction and liquid reaction obtained in this experiment, will be similarly held in carbonation of the other components of hydrated cement.

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MgOとAl₂O₃よりスピネルが生成する反応について, 酸素の役割をあきらかにする目的で, ¹⁸Oを過剰に含むMgOを用いて, 研究を行った. ¹⁸Oを含むMgOの焼結体と, Al₂O₃単結晶またはAl₂O₃焼結体とで反応カップルをつくり, アルゴン雰囲気中で, 1,615℃で170時間または162時間, 反応させた. Al₂O₃片に接着して生成したスピネル層について, スパーク放電形質量分析計を用いて分析し, スピネル層中の¹⁸Oの分布を求めた.
その結果, MgO側のスピネル層には, ¹⁸Oを含むMgO試料と同じ濃度で¹⁸Oが分布し, Al₂O₃側のスピネル層にはAl₂O₃試料と同じ濃度で¹⁸Oが分布していることが見出された. これより, MgOとAl₂O₃からのスピネル生成反応は, スピネルの固定した酸素格子を通ってのMgイオンとAlイオンの相互拡散によることが, 明白に示された.

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The structure of ZnCl₂ glass was studied by X-ray diffraction method and the following results were obtained. In the glassy state Zn-Cl distance is 2.32 Å, and the coordination number of Zn is 4. It is elucidated that ZnCl₄-tetrahedra link each other at their own corners and construct the layer structure similar to γ-ZnCl₂ crystal (shown is Fig. 6). Such model structure is not incosistent with the properties such as melting point, viscosity and etc. Therefore, the structure of ZnCl₂ glass is not so much distinctive and is built up to the network consisting of 4-fold coordinated Zn²⁺ ions. So far as concerning this point, one can find no difference from the well-known structure of conventional glass. Glass-formation range of some binary and ternary systems involving ZnCl₂ as a common component were also studied, which were shown in the Table 6 and Fig. 10.

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