流動層で微小球に炭化ジルコニウム-炭素系複合体の被覆を施こす方法として, ジルコニウムスポンジと二塩化メチレン蒸気との反応生成物からの蒸着が利用できることを実証した. 蒸着物層の炭素対ジルコニウム比は, 供給ガス中の水素濃度を変えることによっても, また, 反応領域の管長を変えることによっても調節できる. 1400℃以下での蒸着は実用的でない.

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Surface structures of nonsinterable BeO powders have been studied on the compositions and amounts of gas desorbed from the BeO powders and the adsorption isotherms of water at 25°C. The BeO powders were derived from hydroxide. As a result of our study, following conclusions were obtained.
1) The beryllium hydroxide, precipitated homogeneously from sulfate solution, contained many sulfate ions. SO and SO₂ gases were desorbed from the BeO powders which had been calcined at temperature less than 1000°C, but little desorption of those occurred above 1000°C.
2) Surface structures of the BeO powders, calcined lower temperature, were sensitive to outgassing temperature
3) Surface structures of the BeO powders were not sensitive to calcination temperature.
4) The largest amount of the chemical adsorption of water was found in the BeO powder which was calcined at 1000°C.
5) Outgassing temperature affected strongly the monolayer capacities of physical adsorption of water vapor on the BeO powders which were calcined at lower temperature, but calcination temperature affected weakly them.

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The spinel layer formed by solid state reaction between periclase and sapphire was investigated with an etching technique. The aims of this study are listed as follows; (1) the determination of the relative orientation of spinel to sapphire (2) the examination of the three-dimensional microstructure of spinel to conjecture the mechanism of crystal growth.
Grinding, polishing, etching and observations with an optical microscope are repeated in this order. The spinel was etched for 40-120 min in conc. H₂SO₄ at 200°C.
According to the results of this experiment on the periclase-grown spinel, the spinel layer consisted of the grains elongated to the growing direction. This is the evidence of the epitaxial growth of this layer.
The sapphire-grown spinel had two kinds of texture; one was observed in the central part of the layer, and another in the surrounding part of the layer.
On the etched face of the central part of the sapphire-grown spinel, triangular etch pits were observed and relative orientation of the spinel layer to sapphire was determined on the basis of the direction of etch pits. The results of the orientation study were in agreement with those of the other authors. The sapphire-grown spinel had the twinning structure, and at the boundary of twinning, deep grooves were formed by etching. These grooves extended along the direction ‹112›, and tended to run parallel with each other. This phenomena were explained from the mechanism of rearrangement of the oxygen atoms at spinel/sapphire interface. At this interface, the oxygen must change the stacking sequence from the hexagonal closed packing of sapphire (…ABABAB…) to the cubic closed packing of spinel (…ABCABC…). This rearrangement is probably performed by the mechanism proposed by Schmalzried et al., i. e. a movement of the bundles of Shockley partial dislocations along the glide planes.
The surrounding part of the sapphire-grown spinel had little tendency to orientate to sapphire, and had a little degree of epitaxy. It was assumed that the sapphire-grown spinel in this region had grown by a sort of exsolution mechanism.

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Changes of the mechanical properties of oxide and oxyfluoride glasses during heattreatment were investigated.
Bending strength of the system PbF₂-ZnO-B₂O₃ was influenced by the shape of crystal, and the stress induced by the difference in the coefficients of thermal expansion between matrix glass and precipitated crystal.
Bending strength of the system PbO-ZnO-B₂O₃ was influenced by the microcracks induced by the difference in the rate of crystallization between the surface and the bulk of glass and also by the shape of crystal, while the difference between the coefficients of thermal expansion was not related to bending strength.
Compressive stress induced by decrease of volume of glass during heat-treatment was not related to bending strength. This seemed to relax during cooling.

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The glass forming region in the system Na₂O-MgO-MgF₂-SiO₂ was examined, and the crystallization of fluor-tetrasilicic mica from the glass when it was heat-treated was studied by the methods of DTA and X-ray powder diffraction and the electron microscopy.
The results were summarized as follows;
1) The clear glass was obtained from the melt containing a lower amount of SiO₂, F or a higher amount of Na₂O than the composition of fluor-tetrasilicic mica (Na⋅Mg_2.5⋅Si₄O₁₀F₂).
2) A larger amount of the mica crystallized from the glass having the composition nearer to Na⋅Mg_2.5⋅Si₄O₁₀F₂.
3) The mica crystallized from the glass had the composition of Na⋅Mg_2.5⋅Si₄O₁₀F₂ and the lattice constants of a=5.17 Å, b=9.08 Å, c=9.81 Å and β=100°.
4) The nucleation and the crystal growth of the mica started after the glassy phase separation. The rate of crystallization of the mica from the glass depended mainly on the rate of nucleation at the earlier stage of the crystallization. The mica phase which nucleated at the earlier stage decomposed during the heat-treatment for a long time at the comparative higher temperature, on the other hand fluor-richterite crystallized.
5) Activation energies for the nucleation and the growth of the mica phase from the glass were obtained as 115kcal/mol and 151kcal/mol, respectively.

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The special technique to manufacture the roofing the with silver lustre has been maintaind from old time in some ceramic districts. Recently the technique has attracted special interest and to make use of it in the modern roofing tile industry is desired.
It is very interesting that the slip of natural iron ore applied on the roofing tile body develops silver lustre under the special firing condition.
To make clear the firing condition for good silver lustre and also the origin of the development of it, this study was carried out. X-ray diffraction and microscopic observation showed that the silver lustre appeared when α-Fe₂O₃ crystals grew remarkably and had the preferred orientation where the basal plane of α-Fe₂O₃ is parallel to the surface of the glaze. For silver lustre the firing in reducing atmosphere is said to be essential. But the α-Fe₂O₃ crystals seemed to grow by the reoxidation at the maturing temperature, so the combination of the reduction in the heating process and the reoxidation at the maturing stage was found to be very important.

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Direct measurements of decomposition temperature of silicon nitride are performed in the highly pure system of Si₃N₄-C-N₂ (1 atm). The result obtained here, 1839°±14°C is the lowest value among the temperature reported. Errors between those temperatures are discussed, Some single crystals of β-Si₃N₄ are obtained through those experiments and the growth condition are briefly reported.

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The glass-forming region for 2g cold water quenched melts in the system As-S-Ag was reported, together with the crystalline phases being teases being contiguous to its region and glass transition temperature. The thermal-induced structural transformation of the typical glasses having widely different compositions has been studied by DSC analysis and X-ray diffraction. 4 figs., 1 table, 8 refs.

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