陰イオンにFを含むLiF-Al₂O₃系のスピネルを熱水法で合成した. 出発原料にLiFとAl₂O₃・3H₂Oを用いその混合モル比が40:60の時, 450℃以上, 水蒸気圧400-800気圧で20-30時間処理すると単味のスピネル相が得られた. このスピネルは格子定数a=7.926 Å (立方, 空間群Fd 3m), 弗素含量10.5±0.5%, 比重測定値3.43 (計算値3.48) で, (Li_64/11, Al_192/11, □_8/11), F_64/11, O_288/11) が単位格子中に含まれる.
同じ出発原料から空気中800°-900℃焼成で得たスピネル相では, 弗素が一部酸素に置換している.

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アルカリ醐酸塩ガラスは紫外線照射により応力が発生する. これは紫外線によるガラスの収縮が原因であることが確かめられた.
ガラスの網目構造の変化過程についての試論が与えられている. これらの過程は二, 三の基礎的事項, すなわち, 紫外線が物質に及ぼす光化学的効果 (励起, 光解離, 光イオン化), 棚酸塩ガラスの網目中の化学結合の特質 (B-O結合, 特にBと非架橋酸素との問の結合の2重結合性, 電子授受に伴なうBの配位変化および非架橋酸素の特異な挙動) および著者等の研究により得られた多くの実験事実に基づいて仮定された. それらは, 1. B-O^-結合の励起と伸長によるアルカリイオンの移動, 2. 励起されたB-O-B結合のねじれと結合角の変化によるBO₃またはBO₄群の回転, 3. >B-O^-結合の伸長により引き起される一つのBO₃三角形の非架橋酸素と近傍のBO₃三角形のBとの問の結合形成とそれによるBO₃からBO₄への転化, 4. 3.と同じ, ただし>B-O^-単位内の電子の移動により引き起されたもの, 5. 3.と同じ, ただし非架橋酸素の光イオン化により引き起されたもの.
これらの過程は, エネルギーの観点からは可能だと期待されるし, 実験事実, すなわち応力の発生と熱的緩和のカイネチックス, 紫外線照射されたガラス中の電荷蓄積, 紫外線照射されたガラス中のESRやその他の電子的中心の少なさなどと合致する. アルカリイオンが応力発生と, 収縮した不安定な網目構造を準安定化することとに及ぼす効果に特に注意を喚起した.

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Generally, opacity of leadless porcelain enamel for aluminum alloys is inferior than lead-bearing porcelain enamel. Previously, enamel of the system PbO-SiO₂-V₂O₅ was studied and good opaque enamels could be made by deposition of lead silico-vanadate having a vanadinite structure in it. The present investigation was undertaken to establish a good opaque leadless enamel of the system BaO-CdO-SiO₂-V₂O₅, in which some vanadate crystalline phases would be depositted.
The results obtained are summerized as follows:
(1) Crystalline phases depositted in these enamels were α-K₂SO₄ type hexagonal xBa₂SiO₄-(1-x)NaBaVO₄ solid solution and monoclinic 8BaO⋅R₂O⋅3V₂O₅ crystal (R represents alkali ion). The other minor crystalline phases in these enamels were tetragonal BaTiSiO₅, perovskite type cubic SrTiO₃ and ilmenite type unknown hexagonal crystal.
(2) The amount of BaO and CdO in frit was governing factor determining which phase would be crystallized in enamel. From the frits containing both BaO and CdO, α-K₂SO₄ type crystalline phase was depositted, but another frits contained only BaO, 8BaO⋅R₂O⋅3V₂O₅ phase was depositted. It was assumed that this phenomena attributed to viscosity-depression of frit by addition of CdO.
(3) From many synthetic experiments with substitution of each cation in α-K₂SO₄ type R⁺Ba(R⁵⁺O₄) compound, it is concluded that the most stable phase in which the cations are exactly fit this structure is NaBa(PO₄).
(4) Chemical durability, particularly acid resistance, of these enamels were inferior to other enamels, e.g. lead silico-vanadate enamels. It was assumed that besides the kind of crystal depositted, diffusion and segregation of a certain ions as alkalis was a factor determining the chemical durability of the enamel.
(5) Good opaque enamels were established by using a higher content of V₂O₅ in frit. Colored enamels were made by addition of Co₂O₃ or CuO in frits. But external appearance of these enamels were, generally, not very satisfactory.
(6) As a result of displacement of BaO by CdO in frit, an increase of thermal expansion, a lowering of softening point and an improvement of chemical durability were observed, but enamels slightly tinged with red were obtained.

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SbSI is a ferroelectric material with the c-axis as ferroelectric axis and the most strongly piezoelectric material known. The permittivity of SbSI single crystal of the c-direction is about 25000 whereas that of the a-direction is 25. Till now, due to the difficulties in obtaining large crystal, it is very hard to use this material for practical applications. Specimens used in piezoelectric measurement reported by RCA group consisted of thin discs cut from bundles of SbSI needles embedded in Araldite.
SbSI single crystal tends to grow in form of thin needles along the c-axis. In this report, the hot-pressing technique was applied to the powder of SbSI crystals in order to obtain the hard polycrystalline ingot having the oriented c-axis and systematic experiments were carried out on the effects of the hot-pressing temperature (T_m), the pressure (P_h) and the time (t_p) influencing upon the orientation of the c-axis in the hot-pressed specimens.
The results obtained are summarized as follows.
(1) When P_h was applied to the z-direction of the press mould, the c-axis of SbSI microcrystals were oriented in the x-y plane of the press mould. In this case, the permittivity of the x-direction (ε_x) is 1400 at the Curie point whereas that of the z-direction (ε_z) is 160.
(2) When the pre-forming pressure to the y-direction and the hot-pressing pressure to the z-direction were applied, the c-axis were oriented to the x-direction of the pressed specimens. In this case, the permittivity of x, y, and z-directions at the Curie point are 3000, 1000, and 240 respectively.
(3) The orientation of the c-axis in the hot-pressed specimens was also ascertained by the observation of the etched surface by mean of a microscope.
(4) The piezoelectric constants such as k₃₃, s₃₃^E, s₃₃^D, d₃₃, f_R⋅t were measured for the hot-pressed specimens prepared under a condition of T_m=370°C, P_h=250kg/cm², and t_p=1hr. This specimens showed an electromechanical coupling coefficient k₃₃ of 35%.
(5) The Curie temperature of the hot-pressed SbSI of 30°C is higher by 10°C than that of the SbSI single crystal If the phase transition of SbSI is order-disorder type, it may be considered that the rise of the Curie point by the hot-pressing is the effect of the residual strain generated while hot-pressing.

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