ガラスの高温粘度測定の自動化, 時間短縮化を目的として, 内筒回転型の粘度計を試作した. 本装置の特長は一定温度あるいは連続温度降下時に, 粘度と温度を同時に, 連続的に測定できる点である. 粘性抵抗によるトルクは “Rotovisko” トルクメーターにより, 電気的に検出される. 内筒中に挿入されたガラス試料温度測定用の熱電対の起電力は, 回転刷子を経て取出され, 記録される. 一定温度における測定値と温度連続下降時 (130-390deg/h) における測定値の間に, 著しい差異は生じなかった. 測定粘度範囲はη=5×10-10⁷Pであり, 測定温度範囲は650°-1500℃である. 温度連続下降による測定は10⁵P以下の粘度で行ない, それ以上では一定温度における測定が適当である. 測定の誤差に本データのばらつき, 再現性から, η=5×10-2×10³PにおいてΔη/η=±5%, η=2×10³-5×10⁶PにおいてΔη/η=±15%であった. 測定に必要なガラス試料は約250gである. 正味の測定時間は1試料あたり約3時間であり, 測定時間の短縮化がなされた.
なお本装置の粘度測定方法は相対測定のため, 粘度既知の試料を用いて装置定数を決めなければならない. 室温における有機物の標準粘性液によって決められた装置定数の値と, 1450℃の高温において, 粘度標準ガラスを使用して定められた値とはほぼ一致し, 室温における装置定数の決定が適切であり, かつ実際的であることが示された.

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Thermal expansion coefficient, glass transition temperature, and deformation point for As-Se glasses have been determined from curves of elongation versus temperature. Data obtained are shown in Table 1 and Fig. 2. The results are summarized as follows:
1) Glass transition temperature, T_g, and deformation point, T_d, increase with increasing the As content up to its maximum at about 40 atomic per cent and then decrease. The relationships of T_g and T_d versus the As content in the range of content 25-30 per cent give the negative deviation from linearity. It seems to be interpreted as evidence for formation of the weak bond of Se, such as nonbridging selenium in the glass.
2) From the values of T_g and liquidus temperature, T_l, in Table 2 it can be seen that the “two third rule, T_g/T_l=2/3” holds fairy well.
3) The relation between thermal expansion coefficient, α, and T_g is given by formula of the equation α⋅T_g²=constant.

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Sapphire single crystals were grown on single-crystal substrate via the chemical reaction 2 AlCl₃(g)+3H₂O(g)=Al₂O₃(s)+6HCl(g) by chemical vapor reaction method at 1600° and 1650°C. The reactant gases, AlCl₃ and H₂O, were introduced into an evacuated reaction chamber using inert gas as a carrier. Most satisfactory results for epitaxial growth on single-crystal substrate were obtained by blowing water vapor off toward the substrate lying in a flow of AlCl₃ vapor.
The deposits obtained on a substrate were grown epitaxially in an optimum range of the flow rate of reactant gases. The growth rate in the direction ‹1100› was faster than that of in any other direction and a two-dimentional growth within a plane perpendicular to c-axis was remarkable. It seems that the overall growth of crystals takes place by repeating the two-dimensional growth on the basal planes. The shape of crystal was resulted in the hexagonal prism consisted of smooth {0001} planes with hexagonal growth patterns and of {1120} planes with parallel-striped patterns.

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Phase separation in glaze containing zinc oxide was studied by infra-red reflection method. The difference in the infra-red reflection spectra in the neighbourhood of 1180 cm^-1 was found between the slowly cooled glaze and quenched glaze in which the growth of phase separated particles was suppressed. The slowly cooled sample was opaque, but no crystal was found by the X-ray diffraction method and the electron-micrography. Many spherical droplets about 0.1μ in diameter were found by electron-microscopic observation.
Phase separation was prevented by the increase of Al³⁺ ion and/or the substitution of CaO, SrO, or BaO for ZnO in the glaze composition.
In the case of non phase separable glaze containing such components, no difference in the shape of infra-red reflection spectra in the neighbourhood of 1180cm^-1 was found between the slowly cooled and quenched samples. The difference in the shape of infra-red reflection spectra of those samples was considered to be based on phase separation into silica rich glass droplets and modifier rich glass matrix.

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Effects of TiO₂ addition on sintering of ZrSiO₄ at 1450°, 1500°, and 1600°C for 1 to 24 hrs. in air have been investigated. Shrinkage after sintering, bulk density, apparent density and apparent porosity of the sintered bodies were measured in relation with sintering time, temperature and TiO₂ content. Mineral constitutions of the sintered samples were identified with an X-ray diffractometer. Microstructures of the sintered bodies were examined by means of an EMA and a reflected microscope.
The results obtained were as follows:
(1) Sintering of zircon was accelerated by addition of TiO₂. Shrinkage and bulk density of the samples increased, and apparent density and apparent porosity decreased with increase of TiO₂ content, sintering time and sintering temperature.
(2) Zircon was decomposed to ZrO₂ and SiO₂ by addition of TiO₂. A solid solution of TiO₂ with ZrO₂ was recognized at 1450° and 1500°C. The formation of a compound ZrTiO₄ was recognized at 1600°C. SiO₂ dissociated from ZrSiO₄ coexisted as crystobalite at 1450° and 1500°C and changed into liquid at 1600°C. ZrO₂ appeared in samples sintered at 1600°C.
(3) Acceleration of sintering of ZrSiO₄ was due to the formation of a solid solution, a compound ZrTiO₄ and liquid. Especially, formation of liquid was one of the most important factors.
(4) In the case of sintering of samples crushed and heated repeatedly, rapid reaction between ZrSiO₄ and TiO₂ was attained. Samples heated at 1600°C and contained TiO₂ less than 5 wt% showed the increase of bulk density, while that of the other samples showed the decrease.

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Composition of silver halide crystals precipitated in the alkali alumino borosilicate glasses containing Ag, Cl and Br was determined by applying Vegard's law.
The ratio of Cl to Cl+Br in precipitated solid solution (=X) was always lower than that in mother glass. The long side wave length limit of light effective in darkening increased monotonously with decreasing X ranging from about 410mμ at X=1 to 470mμ at X=0.

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