AsとSとの割合を種々に変えたAs-S2成分系のガラスをつくり, X線回折法によりその強度分布曲線を得た. 必要な揚合にはさらに動径分布解析を行なった. 一方で原子模型を組み立てて, As-S系ガラスの構造模型をつくった.
これらの結果からAs₂S₃組成のガラスは硫黄の結晶構造と似ていて層状構造を持つが, すきまのかなり多い乱れた構造であると考えられる. As₂S_x(x>3) 組成のガラスはやはり層状構造を持っていて, As₂S₃組成より硫黄が増すにしたがって硫黄はAsとAsとの間に〓S〓_n鎖としてはいり, As₂S_8-10以上になると鎖状の硫黄と同時にS₈環もできてくると考えられる. また, As₂S_x(x<3) 組成のガラスもやはり層状構造を持っていて, As₂S₃組成より硫黄が減少するにしたがって, AsとAsとの間の硫黄がとれて, As-As結合が生じる. それにつれて層がひずみ, 層間隔が広がるようになると考えられる.
上にのべた構造を考えると前報で得られたガラスの硬度測定, 粘度測定の結果や, CS₂によるガラスの溶出実験の結果が非常によく説明できる.

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A method of quantitative determination of granulated blastfurnace slag not only in unhydrated slag cement but also in hydrated paste as an unreacted part was established by using a salicylic acid, aceton-methanol solution. In this solution slag hardly dissolves, but most of the hydrated slag, clinker minerals and their hydrates dissolve. Utilizing this principle, with some corrections if necessary, it is possible to determine the amount of unreacted slag.
The experiment to determine the amount of unhydrated slag on the hydration of various types of slag cement pastes were carried out.
The amount of unreacted slag contained in these cement pastes was determined by using the salicylic acid, aceton-methanol solution. The accuracy of this measurement was found to be satisfactory. Unreacted C₃S was quantified and the hydration products were detected by X-ray diffraction. Non-evaporable water, free Ca(OH)₂, and free CaSO₄ were also determined by chemical analysis, and the hydrated phases were observed under a microscope.
The chemical compositions of the products and the rate of reaction of each component such as slag, C₃S and CaSO₄, and the depths of the reacted layer on the particles of slag and C₃S were calculated from the experimental data.
In every type of slag cement, the rate of reaction of slag contained was unexpectedly slow. Further, after hydration for about 3-7 days, the rate of reaction of slag and C₃S showed a remarkable decrease.

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According to the polaron theory, basic process of electron (or hole) transfer in polar solids transforms from hopping motion into tunnel effect with lowering temperature. In order to investgate this transformation of the electron transfer process in various electronically conducting oxide glasses containing transition metal oxide, the d. c. conductivity and the dielectric properties in low temperature region were studied as a function of temperature and frequency. Measurements were performed over the frequency range from d. c. to 10⁶ Hz at various constant temperatures in the range from 20 to -180°C. Experimental results were discussed in terms of the theory of dielectrics and the polaron concept.
(1) Irrespective of the kind of the transition metal oxides in the glasses, a critical temperature T_c is found in the region of temperature -70° to -80°C on the plot of logarithm of the d. c. conductivity against the reciprocal temperature: the activation energy for conduction at tempertures below T_c is lower by 30% than that above T_c. And so there appear to be some changes in conduction process at temperatures below T_c.
(2) Extend over wide temperature range, the nature of low frequency dielectric absorption has the features in common with the previously reported features of dielectric relaxation in various ionically and electronically conducting oxide glasses. That is; the activation energy for dielectric relaxation is nearly identical with that for d. c. conduction.
And there is a correlation between the d. c. conduction and dielectric absorption as follows;
σ≅ε₀⋅Δε⋅2πf_max
where σ is the d. c. conductivity, ε₀ the dielectric constant for vacuum, Δε the magnitude of dielectric absorption and f_max the frequency at loss maximum. The measure ε″_max/Δε for representation of the spectral spread of the absorption is approximately 0.2, and is independent of temperature as was observed in many glasses. Moreover, this nature of the dielectric relaxation does not change at all even in temperature region below T_c.
(3) If the coexistance of hopping motion and tunnel effect contributes to the decrease of the activation energy for d. c. conduction in temperature region below T_c, the nature of the dielectric relaxation of the glasses, which may be closely related to conduction process, must change remarkably. However, any drastic change in the relaxation behavior is not observed at temperatures below T_c. Therefore, it seems likely that hopping motion yet predominates even in temperature region below T_c.

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Thermal decomposition of aluminum sulfate into α-alumina was investigated by D. T. A., T. G. A., X-ray analysis and electron microscopic observation.
The results obtained were as follow:
Aluminum sulfate melted in its own water of crystallization when heated, and high viscous solution was obtained. This solution evaporated vigorously above 100°C. Bubble formation was observed because of difficulty in releasing water vapor due to high viscosity of the solution. Then the skeleton particles composed of the network of thin film layers were formed. They were decomposed to r-alumina keeping this shape. The r-alumina consisted of very fine particles. A remarkable grain growth was observed together with transition to α-form. The transition initiated from a part of a skeleton particle with a rapid rate. From this fact, the rate controlling process may be the nucleation.
It was confirmed by the electron diffraction that the inside of the skeleton particle showed a high orientation because the transition and grain growth proceeded from one or a few nuclei.

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Single crystals of rutile (TiO₂) were grown from several fluxes. The good results were obtained with Li₂O-MoO₃ flux systems. Using Li₂O-m MoO₃ fluxes, the habit and color of growing crystals vary with the amount of MoO₃, which bring with it single crystals comparatively large in size. They vary continuously in form and color, from needle-like transparent crystal to prism-like and short-prism-like, black or opaque crystals.
The growth experiments were carried out by slow-cooling method, temperature of growth being 1250°C to 800°C and cooling rate with 7°C/hr. The grown crystals obtained in such a method have needle-like habit 15 to 20mm in length elongated to c-axis and prism-like 1.5mm in diameter and 10mm in length, both being comparatively large in size and transparent free from inclusions.
The solubility of rutile was measured from 1000° to 1300°C in Li₂O-2MoO₃ solvent, and also flux composition was varied from m=1 to m=3 at constant temperature 1150°C. The solubility was found to slightly increased dependent on MoO₃ content. The dependence on temperature was found to almost linearly increased ranging from 1200° to 1300°C.

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The reaction between iron oxides (specularite α-Fe₂O₃, magnetite Fe₃O₄) and magnesia was investigated with single crystal X-ray diffraction. Under conditions where magnetite was stable (for example at 1300°C in CO₂ gas) magnetite reacted with magnesia bearing a topotactic relation of high order. Since the X-ray diffraction pattern of the product (MgFe₂O₄) had single crystal characteristics and was practically identical to that of the reactant (Fe₃O₄), it seemed that iron and magnesium ions counter-diffused in the rigid oxygen framework of magnetite. Specularite reacted with magnesia bearing a topotactic relation of low order. Streak along Debye arcs appeared in X-ray diagrams of α-Fe₂O₃ and spinel phase. The single crystal X-ray study showed the following relative orientation between the reactant (α-Fe₂O₃) and the product (MgFe₂O₄) in these reactions; (0001) _α-Fe2O3//(111)_MgFe2O4 and [1010]_α-Fe2O3//[101]_MgFe2O4.

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