The composition change of silicate glaze was studied from peak shift of infrared reflection spectrum. By applying the theoretical formula concering to infrared absorption spectrum peak on crystal. The relation between peak shift and glaze composition was discussed.
The peak shift to longer wave length of Si-O bond peak with the increase of amount of cation in crytal is dominated by electrostatic interaction of cation to oxygen in the structure.
Besides electrostatic interaction in glass structure that is influenced by the relaxation of structure according to cation penetration.
The results obtained were as follows.
1. Peak shift to longer wave length in glass structure with increase of Al ion was larger than in crystal one because of the relaxation effect of Al ion.
2. Peak shift due to increase in basic component in glass structure was smaller than that of crystal one because of the breakage of oxygen bridge in glass structure.
3. Peak shift due to increase in ionic radius of alkali earth ion in glass structure was smaller than that of crystal structure because of relaxation structure of glass.
Accordingly, the theoretical formula of peak shift on crystal structure could also be applied to glass structure by introducing the factor decided by introduced cation in glass structure.

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Hydro-thermal synthesis on the aluminium ion containing tobermorite was studied using pyrophyllite as a source of Al₂O₃. Reactivity of pyrophyllite in the system CaO-Al₂O₃-SiO₂-H₂O and the influence of Al₂O₃ on the crystal structure of the product were investigated through the preparation of hydrous calcium silicate crystals containing various amount of Al₂O₃. In general, pyrophyllite had been considered stable chemically, but it was proved that pyrophyllite had a special reactivity in the hyhdro-thermal treatments, that is, according to our results, more than 54% of Al₂O₃ in pyrophyllite was participated in the reaction for 8 hrs treatment and more than 63% of Al₂O₃ was similarly for 24 hrs treatment at 175°C.
Tobermorite contained Al₂O₃ higher than 3% shown the structural disorder, and the lattice constant of tobermorite crystals which were prepared by the experiment, was changed by addition of pyrophyllite up to 7%, as Al₂O₃ for the system CaO-Al₂O₃-SiO₂-H₂O.
Consequently, Al-containing tobermorite is distinguished from Al-free tobermorite by the X-ray diffraction analysis, D. T. A. and the electron diffraction patterns. These without Al-containing tobermorite and hydrogarnet were produced by addition of pyrophyllite more than 7-9% as Al₂O₃.

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Heat capacities, thermal conductivities and melting points of several condensed phosphates, both in crystalline and vitreous states, were measured. The effects of cations on the thermal properties were discussed in connection with structural characteristics of the phosphates.
The heat capacity C₅₀ per gram formula weight at 50°C of vitreous phosphate with the chemical formula xM_mO_n⋅(1-x) P₂O₅ could be expressed by an empirical equation C₅₀=Ax+B(1-x). Coefficients A and B in the equation were between 7 and 16 and between 28 and 38, respectively, depending on the systems investigated.
The gram-atomic heat capacity was lower for vitreous metaphosphate containing cation with high ionic potential than for that containing cation with low ionic potential. The heat capacity of metaphosphate seemed to be determined by a function of two characteristic temperatures which were related to the vibrations of cations and macroanions, respectively. A reasonable assumption is as follows:
The characteristic temperature related to the macroanions does not change significantly with the change of cation in the metaphosphates. The macroanion skeletons are bound together more tightly by cations with higher ionic potential than by the cations with lower ionic potential. Therefore the characteristic temperature related to a cation with higher ionic potential is higher. The dependence of the gram-atomic heat capacity on the ionic potential of cation can be explained by the difference in cation-skeleton interaction, or, in other words, by the difference in the characteristic temperature related to cation.
Both thermal conductivity of the vitreous metaphosphate and melting point of the crystalline metaphosphate increased with an increase of ionic potential of cation in the phosphates. This also can be explained in terms of the change of interaction between macroanions through cations.

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Studies on the crystallization of the glasses and the properties of crystallized glasses having the composition {Li₂Ca (Mg_5-xAl_x) (Al_xSi_8-x) O₂₂F₂} were carried out. Those compositions were obtained by the isomorphous substitution of the F-richterite composition {Na⋅NaCa⋅Mg₅⋅Si₈O₂₂F₂}.
The results obtained were summarized as follows:
1) The crystallized glasses having the compositions of Li₂Ca(Mg₃Al₂)(Al₂Si₆) O₂₂F₂+0.75, 1.0, 2.5mol Li₂O heat-treated at 950°C for 2-3 hours had very large negative thermal expansion coefficients and their crystalline phases were mainly β-quartz (ss).
2) Accoding to J. Petzoldt, the crystallized glass having the composition of eucryptite (LiAlSiO₄) and heat-treated at higher temperatures has a larger negative thermal expansion goefficient (at 900°C α≈-10×10^-7/°C at 1000°C α≈-70×10^-7/°C). β-quartz (ss) precipitated at higher temperature in the glass having the composition of eucryptite has larger lattice constant c_hex, so that from the value of lattice constant c_hexof β-quartz (ss) the value of thermal expansion coefficient of β-quartz (ss) may be presumed. In this investigation, β-quartz (ss) precipitated at 900°C in the glasses containing more than 0.75mol excess Li₂O had larger lattice constants c_hex than that of precipitated at 900°C in the glass having the composition of eucryptite, and β-quartz (ss) precipitated in the glass containing more than 1.0mol excess Li₂O had nearly the same value of lattice constant c_hex as β-eucryptite.
3) In the glass having the composition {Li₂Ca(Mg₄Al)(AlSi₇)O₂₂F₂}, the crystallization started at the glass surface and the strength of the crystallized glasses, heat-treated at relatively lower temperature, increased with treating time.

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The solid state reaction of spinel formation between MgO piece and Al₂O₃ piece was investigated for the purpose of obtaining the reliable data for rate of reaction, concentration gradient in the spinel layer and thickness ratio of two spinel layers.
Typical microscopic photographs of reacted pieces in thin section are shown in Fig. 5-8. Conditions and results of reactions are shown in Table 3. In the table the following facts can be read: (1) The effect of specimen, single-crystalline or poly-crystalline, on the rate of reaction is not so distinct. (2) The reaction proceeds following the parabolic law as shown in Fig. 16. (3) The thickness ratios of two spinel layers become larger at higher temperature. (4) The composition of the spinel on the contact face with Al₂O₃ is equilibrium composition suturated with Al₂O₃. The fact is also seen in the result of X-ray examination of the spinel ground layer by layer, as shown in Fig. 11. (5) From the values of reaction constants, k (cm²/sec), the so-called activation energy for the reaction was calculated to be 92kcal/mol as shown in Fig. 14.
The EPMA and X-ray examinatin showed the obvious concentration gradient in the spinel layer as shown in Fig. 10. The material transport for the spinel formation is owing to the interdiffusion of 3Mg²⁺ _??_ 2Al³⁺, through the diffusion field with this concentration gradient.

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The apparatus for DTA was devised to study the thermal changes above 2000°C and was applied to measure the melting point of Al₂O₃. It was determined to be 2054±6°C (IPTS 1968) in this work. This value is in good agreement with literature value already published. The thermocouple (W 3% Re-W 25% Re) used for measuring temperature was calibrated by using quartz, Ag, Au, diopside, Pd, wollastonite, and Pt. Heating rate was 3°C/min and atmosphere was Ar containing H₂. ThO₂ was used as a reference material. Heater, cells and crucibles are all made of tungsten in order to endure under high temperature above 2000°C. This apparatus can be used in vacuum, hydrogen gas or inert gases, and its sensitibity is ±5μ V from 1000°C to 2300°C. 4 figs., 1 table, 3 refs.

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The spark source mass spectrometry was applied to the analysis of ¹⁸O in solid oxides. After some trials such method was adopted successfully that a solid specimen was wound around by gold wire and a pointed gold wire was set as a counter-electrode. After the ion source chamber was evacuated, the specimen was heated for 30 minutes by the use of the heater set in the chamber in order to remove the adsorbed water. As a result of this treatment the influence of the water was erased. The quantitative analysis was performed by comparing the density of the spectrum of ¹⁸O⁺ with that of ¹⁶O⁺. The crater sizes were measured by the microscopy and the depth of sampling was estimated at the order of 5μ. The method stated in this note will be applied validly to determine the ¹⁸O distribution in the diffusion couple or the product layer formed by solid state reaction. 2 figs., 3 tables, 2 refs.

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