Deformation and grain orientation of polycrystalline hexagonal Ba-ferrite under uniaxial compressive load were studied. The polycrystalline Ba-ferrite deformed smoothly under a load of 200kg/cm² at the temperatures ranging from 1100°C to 1300°C. For example, polycrystalline Ba-ferrite with the reduction ratio of height of 63% did not show any failure. In a polycrystalline Ba-ferrite with reduction ratio of 6.5%, any microstructural change was not observed. However, the microstructure of the polycrystalline Ba-ferrite changed with increasing reduction ratio. In the reduction ratio of 47.7%, the largely deformed grains which located near the outer surface of the pellet elongated to the perpendicular direction to the load. The polycrystalline Ba-ferrite with reduction ratio of 56.8% showed both grain elongation and grain growth. The orientation degree of c-plane of Ba-ferrite crystal to the perpendicular direction to the load axis increased with increasing reduction ratio. But, the contribution of grain elongation to the orientation degree of c-plane was less than the contribution of grain growth. When the polycrystalline Ba-ferrite with elongated grains was annealed at a higher temperature, the elongated grains grew topotaxially and showed the high orientation of c-plane, although the grains had not the original elongated shape after grain growth. These results showed that well-oriented polycrystalline Ba-ferrite with orientation degree more than F=0.9 could be obtained by the topotaxial grain growth of the elongated grains after annealing.

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Translucent aluminum oxide-to-Nb metal seals were formed by a modified solder glass technique and the interfaces between the materials were examined by an optical microscope and an electron microanalyzer. The solder glass was formed from 3CaO⋅Al₂O₃⋅6H₂O (Hydrogrossularite) and so on, and belonged to the system CaO-Al₂O₃-SiO₂-MgO. The solder glass was melted at 1500°C during sealing operation and crystallized into a glass-ceramic composite on cooling.
The results were as follows:
1. Vacuum tight seals were formed by this technique.
2. The solder glass which turned into a glass-ceramic composite contained 3CaO⋅Al₂O₃⋅3SiO₂ (Grossularite) as a main constituent phase with small amount of 5CaO⋅3Al₂O₃ (Calcium Aluminate) and 3CaO⋅2SiO₂ (Calcium Silicate).
3. Transition layers with concentration gradients of Al and Nb were formed in solder glass at the ceramic-solder glass and metal-solder glass interfaces, respectively.
4. Si concentrated anomalously at metal-solder glass interface, suggesting that surface energy at the interface was lowered by the presence and concentration of Si or SiO₂.
Both the existence of transition layers and the anomalous distribution of Si were expected to strengthen the ceramic-solder glass and metal-solder glass interfaces and relieved the stress concentration caused by thermal expansion difference between the materials.

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Crystallization characteristics of the glass having the molar ratio, CaO/P₂O₅=1.22 and/or (CaO+H₂O)/P₂O₅=1.28, of which average chain length (P_n) was estimated to be 7, were studied by means of high temperature microscopy, high temperature X-ray diffraction technique and IR absorption spectroscopy.
1. Crystalline phases formed in the glass below ca. 650°C consisted of trömelite and trace of β-calcium metaphosphate.
2. Crystal growth rate, G (μ/min), of trömelite in the blown film sample at 680°-740°C was represented by the following equation: logG=25.6-25.0×10³/T.
3. The overall isothermal crystallization curves of the glass powder in size from 44 to 74μ at 600°-650°C were coincided with the Kolmogorow-Avrami equation, where Avrami exponent (m) had different two values depending on the crystallinity (V), and no induction period for the crystallization was found in all the curves.
4. In the range V<0.5, it was inferred that the crystallization took place through the one-dimensional growth with athermal nucleation and in part the three-dimensional growth with thermal nucleation. In the range V>0.6, the crystallization was found to contain the thermal nucleation and the three-dimensional growth.
5. The activation energy for the growth was approximately in accordance with the energy for the crystallization, the values, 110-130kcal/mole, being comparable with P-O-P bond energy.
6. The crystallization of the glass seemed reasonable to be in part accompanied by the polycondensation resulted from evolution of OH-radicals from P-O-P chain ends.

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Electric conductance and density of molten oxides were measured in the systems, 2PbO⋅B₂O₃-CuO, 2PbO⋅B₂O₃-TiO₂ and 2PbO⋅B₂O₃-Fe₂O₃, containing CuO, TiO₂ and Fe₂O₃ from 0 to 25mol% respectively. The structure of these molten oxides and behaviours of Cu²⁺, Ti⁴⁺ and Fe³⁺ were discussed.
Conduction mechanism in these melts is ionic, the same as in the system PbO-B₂O₃, and the mobility of cations depends upon the structure of borate complex anions.
In 2PbO⋅B₂O₃-CuO melts, CuO is considered to dissociate into Cu²⁺ and O^2- ions. In the melts containing less than about 15mol% CuO, the degree of dissociation of borate complex anions seems to increase with increasing CuO content. The increase in the mobility of cations (mainly Pb²⁺) and the decrease in the partial molar volume of CuO are considered to be caused by the dissociation of CuO and borate complex anions. In the melts containing more than about 15mol% CuO, contribution of Cu²⁺ ion to electric conductance increases. The concentration of free O^2- ion also increases, as in the system PbO-B₂O₃ containing more than 75mol% PbO. Anionic contribution to electric conductance is no longer negligible, when the concentration of O^2- ion is high.
Ti⁴⁺ and Fe³⁺ are considered to form oxyacid ions. When TiO₂ or Fe₂O₃ content increases, borate complex anions associate into larger or more complex anions. Then, mobility (equivalent conductance) of Pb²⁺ ion decreases. The partial molar volume of TiO₂ or FeO_1.5 increases in the melts containing TiO₂ or Fe₂O₃ up to about 10mol%. But in the melts containing more than about 10mol% TiO₂ or Fe₂O₃, the increase of free Ti⁴⁺ or Fe³⁺ reduces the partial molar volume of TiO₂ or FeO_1.5.

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The electrical resistivity of sintered bodies of ZnO doped with Al₂O₃ was measured as a function of the sintering degree over the temperature range from 150°C to 700°C by using AC bridge.
The effect of electrode on the resistivity of sintered bodies of ZnO is significant in case of two-probe method. It was confirmed that indium electrode gave rise to the most ohmic contacts among various metal electrodes investigated.
From consideration of the activation energy, the mechanism of electronic conduction in the low temperature region is different from that in the high temperature region.
In the low temperature region, the activation energy decreases with an increase of the sintering degree; finally the value reaching zero as for the well-sintered specimen. The effect of the sintering degree upon the resistivity is remarkable. The resistivity decreases about three orders of magnitude with increase in the sintering degree from 49% to 80%, which is far greater than the change in carrier concentration due to valency control mechanism. Therefore, property of the sintered bodies must be discussed especially in taking consideration of texture.
In the high temperature region, on the other hand, the effect of the sintering degree on the activation energy and the resistivity is smaller than that in the low temperature region. It may be thought that there takes place an electronic conduction independent of the texture of the sintered bodies.

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大出力ガラスレーザー用素子の開発に関する研究の一部として, レーザー光に対する耐久性の高いガラスを得るために, 種々の光学ガラスについて, Qスイッチガラスレーザー光による内部損傷の閾値を測定し, 耐久性とガラス組成の関係, およびそれを支配する要因などに関して検討した.
その結果, 損傷の閾値は, ガラス形成酸化物の含有量が増すにつれて増加すること, 修飾酸化物としてBaOやLa₂O₃を含むガラスでは比較的大きいが, PbO含有ガラスでは著しく小さいことなどがわかった. さらに, 閾値は, ガラスの分散が減少するにつれて, また, 熱拡散率が増すにつれて, それぞれ増大することを見出した.
損傷の閾値と分散との相関に基づいて, レーザー光に対するガラスの耐久性は, 主として, ガラスの固有吸収の振動数に依存し, それが大きいほど高いといえるが, ガラス構造における酸素イオンの充填度が大きいことも, 耐久性の増大にとって効果があると考えられた. このことは, 損傷の閾値は, 網目構造の振動数および酸素イオン内での電子遷移エネルギーなどの大きさに依存すると考えられる, Sharmaらが提案している損傷の機構との関連において説明することができる.

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The phosphate of trivalent cerium have been found to be dimorphic. One phase is monoclinic, the other is a hexagonal structure reported by Mooney (1948). However there are several unknown points in these dimorphic forms, such as the stability range and the transformation temperature. Cerous phosphate of a hexagonal form was synthesized, and the following results were obtained.
1) The hexagonal form has zeolitic water at low temperature, so that the formula was given CePO₄ 0.5H₂O. This zeolitic water was dehydrated at 225°±10°C. After dehydration the hexagonal form is anhydrous.
2) Dehydrated CePO₄ of the hexagonal structure was easily rehydrated when it was kept in a room of ordinary humidity for one day.
3) The anhydrous CePO₄ transformed from a hexagonal into a monoclinic form at about 500°C. This transformation is monotropic and sluggish.
4) The monoclinic form is the same as the mineral monazite. The cone of monoclinic CePO₄ could not be bent down by firing above 1950°C and was not decomposed. The monoclinic CePO₄ is stable at high temperature as is the case of monazite.

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固定内の自己拡散定数 (D*) を求めるのによく用いられている順次切削法では, 実験的に得られたトレーサーの濃度分布は, 通常, ガウス曲線C=M/√πD*t exp(-x²/4D*t) に一致するとして解析されている. ガウス曲線は, 拡散方程式を初期条件にデルタ関数状のトレーサー分布を仮定して解いた解である. しかし, 試料表面に付着されるトレーサーを含む化合物の厚さは, 実際には有限であり, また, その化合物が試料と化学形を異にし, 表面付着層と試料中での拡散定数が異なっている場合もしばしばある. 従来はこうした事情を考慮して拡散方程式が解かれていないので, 本研究では付着層の厚さ (h) が有限値をとり, 付着層中での拡散定数 (D_A) と試料中での拡散定数 (D_B) が違うとして拡散の偏微分方程式を解き厳密解を得た. その結果, 一定のD_B/D_A値に対して, r値 (r=h/√D_At) がゼロから無限大に増加するにつれ, 濃度分布はガウス曲線から誤差補関数曲線へと変化していく挙動が定量的に明らかになった. 濃度分布が両曲線のいずれかに一致している場合には, その曲線から正確なD*の値を得るための数学的に厳密な解析法があるが, いずれにも一致しない中間的な分布の場合には, 正確なD*を求めることは困難である. したがって, 自己拡散定数を正確に求めるためには, 濃度分布が両曲線のいずれかに一致するように, あらかじめ実験条件を設定しておく必要がある. こうした実験諸条件の許容範囲を示すために, (r, D_B/D_A) 平面を濃度分布が1%以内の誤差で, ガウス曲線に一致する領域, 誤差補関数曲線に一致する領域, 両曲線に共に一致しない領域の3領域に分けて図示した. TlCl単結晶にNaClの形でClのラジオアイソトープ, ³⁶Clを付着させ, ³⁶Clの拡散を行なわせて得られる濃度分布を測定し, これらの議論を実験的に例証した.

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