In the process of glass formation by the automated machine manufacturing, the presence of temperature of glass, especially in the peripheral areas surrounding the inner surface of mold does hold a serious bearing as the deciding factor for success or failure in securing the desired quality product.
Particularly does such temperature find itself heavily swayed by the extent of the magnitude of the layer's thickness lying in-between the mold and glass.
By means of utilizing the analogue computer, the research experiment had been conducted by E. Deeg on the movement of heat at the time of glass formation within such mold-glass interface.
It was claimed by M. Coenen through his experiment that such layer's presence can be entirely ignored from being taken into any account whatever.
Using the special method which is to be the measurment of the glass viscosity, W. Trier estimated the temperature distribution of glass in the blank mold as well as the thickness of layer. Following after his experiment, this report is made as to the presentation of the theoretical analysis that was conducted by the author.
Such a thermal property as thermal conductivity, specific heat and specific weight of glass, together with the heat transfer and heat radiation of very thin zone between glass and mold were treated as the function of temperature.
In this manner, because it is extremely difficult under the transint states, to obtain some tangible solution in a strick sense for the non-lineal, the digital computer was utilized in arriving at the numerical solution.
Thus, by this means of approaching upon the procedural, bases on the comparisions, it was found from the evaluation actually computed as against those of the experimental data, it has thereby been enabled to clarify many aspects which had been left undisclosed up till now dealing with the problems of interface layer and the mechanism of the heat flow within the peripheral layer inbetween the area of mold-glass interface.

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チタン酸鉛 (PbTiO₃) が析出する高誘電率結晶化ガラスを製造するための, 基礎的指針を得る目的で, PbO-TiO₂-Al₂O₃-SiO₂系におけるガラス化組成範囲, ガラスの結晶化過程および結晶化ガラスの誘電的性質などについて調べた.
PbO-TiO₂-SiO₂系のガラス化域は, BaO-TiO₂-SiO₂系の場合と異なり, 組成中のSiO₂をAl₂O₃で置換してもほとんど変化しないことがわかった. さらにその原因についてガラス構造の点から考察した.
PbO-TiO₂-Al₂O₃-SiO₂系のガラスは620°-740℃で結晶化し始め, ペロブスカイト型チタン酸鉛 (PbTiO₃) およびパイロクロア型のチタン酸鉛などが析出した. ガラス組成中のAl₂O₃はガラスの分相を促進し, その結果ペロブスカイト型PbTiO₃の析出を促進することが見出された.
本系のガラスを620°-740℃の温度で加熱することにより30-70 (10⁶c/sで) の誘電率を有する結晶化ガラスが得られた. PbO 40, TiO₂ 25, Al₂O₃ 10, SiO₂ 25モル%の組成の結晶化ガラスについては誘電的性質と微細構造, 特に析出したPbTiO₃の結晶量, 軸比, 粒径および粒子の連続性などとの関係について考察した. 本系の結晶化ガラスについては, 試料の厚さによる誘電的性質の変化は認められなかった.

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Some borosilicate glasses having limited compositions will be separated, by the heat treatment in the transformation range, into two glass-phases. One of them is acid-soluble B₂O₃⋅Na₂O phase and the other is acid-insoluble SiO₂ phase. When the segregated glass is acid treated, B₂O₃⋅Na₂O phase is leached out leaving SiO₂ rich porous glass without any destruction of original shape. This porous glass shrinks about 30% in volume by firing between 900°C and 1200°C, turning into 94-98% SiO₂ glass having quartz glass-like properties.
Object of this study is to clarify the relation between glass compositions and treatments of original borosilicate glass to make the above-mentioned porous glass.
Experimental results were summarized as follows:
(1) Minimum time required for phase-separation, t, were measured for various glasses at various temperatures. For every glasses, liner relation exists between log t and the reciprocal of the absolute temperature of heat treatment.
The required time for phase-separation change with glass composition about ten times, however log t-1/T relation for various compositions showed identical gradients, and the apparent activation energy of phase-separation calculated from these results was 62kcal/mol. These values correspond to activation energy of oxygen diffusion in glasses.
Linearity was found between log t (at 500°C) and Na₂O/B₂O₃ mole ratio of these glasses.
(2) The leaching rate by 1 N-H₂SO₄ of B₂O₃⋅Na₂O phase of sufficiently segregated glasses were measured at 100°C, 80°C and 60°C. It was found that the rate changes about ten times depending on SiO₂ content and Na₂O/B₂O₃ mole ratio, and this will be explained in terms of difference of diameter of pores in SiO₂ membrane for each glass.
Linear relation between the thickness of leached layer, δ_M*, and square root of leaching time, √t, was found for every glass examined. Plotting of log δ_M* √t versus 1/T for various compositions gave straight lines of nearly same slopes, from which activation energies of leaching in the range 6.5-6.8kcal/mol were obtained.
From these results, it is concluded that, as far as sufficiently segregated glass is concerned, the rate controlling process of leaching may arise from the diffusion of B₂O₃⋅Na₂O through porous SiO₂ membrane filled by the acid.
Anothr linear relation was found between log δ_M*/√t-SiO₂ content as well as between log δ_M*√t-Na₂O₂/B₂O₃ mole ratio.

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酸化亜鉛単結晶の圧電半導体としての性質を利用して, トランスジューサー, 超音波増幅素子としての応用が考えられている. 水熱条件下で得られるZnOはその雰囲気が還元性であるために, 不純物無添加の場合は過剰Znが格子間位置を占めて暗抵抗を低下させる. そこで, 筆者らは, その補償のために, Li⁺, Cu⁺などを不純物として添加し, また, 光学増感的な立場からMn⁺⁺などの不純物添加を試みて, その波長吸収特性やドープ量, 色調などの光学的な検討を行なった.
Li-ZnO; 結晶中にドープされるLi量は数ppm-10ppmまでで, この範囲の濃度変化では結晶の色調, 波長吸収には顕著な変化は認められない. しかし, 電気抵抗の変化は著しい. Li吸収の位置は398mμであり, 光電導もこの近くに現われる.
Cu-ZnO; 10²ppmオーダーの量がドープされ, Cu吸収と思われる波長は440mμで光電導効果と一致する.
Fe-ZnO, Mn-ZnO; 共にドープ量の変化により, 色調, 吸収の位置の変化が著しく, 不純物量を増加して行くと色は濃くなり, 吸収の位置も長波長側にずれ, 電気抵抗の減少をみる. Mn量の少ないLi-Mn-ZnOについて, 光学増感的な意味で目下検討中である.

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The transformation of β-SiC in a high purity to α-SiC has been studied experimentally in the temperature range from 2100°C to 2300°C. The results obtained are summarized as follows:
1) At the initial stage of the transformation only the 6H-type was found as a newly grown phase. The 15R-type appeared always after the formation of 6H. However, the 15R thus derived disappeared with the progress of the subsequent heating. The 4H-type was not recognized throughout the present experiments.
2) The 6H-type has, in the range of 2100°-2300°C, a thermal stability higher than the other basic polytypes of SiC such as 3C, 4H and 15R.
3) The β-α transformation is considered to take place mainly through a vapour phase, because the activation energy associated with this change was estimated to be as high as 134±4kcal/mole. However, it should also be pointed out that a premonitory twinning is required to complete this transition unobstrusively.
4) The 15R-type is considered to grow, not direct from β-SiC, but through the 6H type already formed.
5) The possibility is conceived that 15R is a metastable form in the whole range of temperature. On the other hand, if a proper stable range exists for this polytype, it will be very narrow indeed, probably at about 2000°C.

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In order to study the relation between the diffusion mechanism of alkali ions and the structure of glasses the self-diffusion coefficients of cesium ions in cesiumsilicate glasses, Cs₂O-xSiO₂ (x=5.0, 6.0, 7.0), have been measured. The isotope ¹³⁷Cs was employed as a tracer. The pre-exponential terms and activation energies for diffusion and electrical conductivity were calculated from Arrhenius-typed plotting. So-called correlation factors were also calculated for the glasses by the modified Nernst-Einstein relation, yielding factors about 0.2-0.3 for each glass. These values were discussed with respect to the preferential paths for the ions, which are supposed to arise from the inherent submicroscopic heterogeneity of the glass.

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Changes in micro-structure of set alumina cement mortar were studied under various conditions by electron microscope in comparison with mineralogical changes. The soft mortar specimens were cured at three different temperatures. The specimens cured under the accelerated converting condition were also examined. It is found that the rate of crystal growth of C₃AH₆ is greatly influenced by the curing temperature and that the distinct difference in the micro-structure exists between the set mortars cured at 20°C and under the accelerated converting condition. Even if the crystalline hydrates produced under various conditions are exactly the same, their textures are not always the same. The texture of the set mortars becomes a little less compact under the accelerating condition than the case of the normal curing. The mechanical strength of the mortars cured under the normal and the accelerating conditions is different from each other corresponding to their micro-structures.

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