For both ionic conduction and electronic conduction oxide glasses, the temperature coefficient of electrical conductivity is positive.
In the limited temperature range, conductivity is usually described by the Arrhenius equation
σ=σ₀exp(-ΔH/RT)
where σ₀ is constant and ΔH is the so-called activation energy for conduction. This activation energy might be thought to be different throughout the glass. Therefore, it is suggested that the Arrhenius equation does not hold for the glass having a wide distribution of activation energy. An attempt was made to consider the electrical conductivity of the glass having a wide distribution of activation energies in terms of three conduction models as follows:
(1) parallel model
ln σ=-ε₀/RT+ln σ₀+1/2a²R²T².
(2) series model
ln σ=-ε₀/RT+ln σ₀-1/2b²R²T².
(3) parallel and series coexistent model
ln σ=-ε₀/RT+ln σ₀+1/2a²R²T²-1/2b²R²T².
where ε₀ is the average activation energy for the conductivity of the glass, a and b are the distribution width parameter.
The ε₀ are equal to ΔH when the glasses does not have a wide distribution of activation energy.

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The sintering of the α-alumina powder derived from aluminum sulfates which were precipitated from the solution containing 0.01 and 1mol% of sulfates of Sn, Mn, Ti and Cu was studied. The sinterability of these samples decreased in the following order;
Sn>Mn>Ti>Cu>free from additives.
The sinterability was little affected by the amounts of additive. By the SEM and porosimetry, it was proved that the differences in the sinterability of these powders were attributed to the differences in the structure of the green compacts. The powder compacts containing hard secondary particles have typical double structure which consists of small pores in a secondary particle and large pores between secondary particles.
The samples with Cu and no additives had such a double structure, and showed a low sintered density. Such welldefined double structure was not observed in the compact of the powder containing Sn, which showed a higher sintered density. The formation of hard secondary particles can be ascribed to the strong bond of inner-particles. The bond strength may be affected by the following two factors; nucleation rate of γ→α transformation and the degree of interruption of contact between particles by the adhesion of additives on the particle surface.

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The reactions of fused cast Na-β-alumina refractory with Na₂CO₃ and with Na₂SO₄ were studied. The fine particles of β-alumina (<5μ) reacted with Na₂CO₃ above 70°C as follows;
Na₂O⋅11Al₂O₃+xNa₂CO₃→(1+x)Na₂O⋅11Al₂O₃+xCO₂↑
The most Na₂O-rich β-alumina, namely, 15mol% Na₂O β-alumina (Na₂O⋅5.7Al₂O₃) was formed below 450°C. However, over the range 450° to 900°C it was transformed to 10.2-10.4mol% Na₂O β-alumina by volatilization of Na₂O. This composition was almost the same as that of the most Na₂O-rich β-alumina formed by the reaction of the coarse grains of β-alumina (0.5-0.84mm) with Na₂CO₃ and the reaction of the fine particles β-alumina with Na₂SO₄. Above 620°C, β-alumina reacted with Na₂CO₃ to form NaAlO₂.

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The exothermic nitriding reaction between powder aluminium and nitrogen gas (N₂) was previously studied by differential thermal analysis and thermogravimetric analysis.
On the basis of the results obtained, the fluidized-bed reaction method was adopted in order to diffuse the heat of the reaction (ΔH=-76.4kcal/mol) which causes cohesion of the aluminium particles and enhances the nitriding of aluminium particles in its vicinity. This method was also suitable to attain good contact between the aluminium surface and the N₂ gas.
The material used is aluminium powder diluted with AlN powder, to prevent the localization of reaction heat; i.e. the composition is Al (20wt%)-AlN (80wt%).
Prior to the reaction experiments, the fluidization of the powders were observed at room tomperature with a transparent glass tube. And, the flow conditions were determined: N₂ flow-rate 11cm/sec, and optimum particle sizes Al (74-105μ)+AlN (149-210μ). This was then followed by the experiment in an alumina tube on the fluidized-bed nitridation at elevated temperatures 1050-1200°C.
Since the aluminium particles are in flow, the cohesion hardly occurs in reactions at temperatures beyond the melting point of aluminium (658°C). Due to the difference in thermal expansion between the AlN coating layer formed at surface by nitriding and the internal molten aluminium, and also to the vapor pressure of aluminum, there occur cracks in the AlN coating layer. The nitriding reaction therefore proceeds at rapid rate. This phenomenon is explained by the model representation. After the nitriding reaction, because of the gas phase reaction between vapourized Al and N₂, some fibrous crystals deposited on the surface of the particles at 1050-1100°C. These crystals grew to needles at 1150-1200°C.

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シリコン粉末と窒素との反応で得られた生成物を電子顕微鏡を用いて調べ, 形態観察の結果を基に反応機構を考察した. 反応の速度が, シリコン粒子径の平方根に比例する事実は, Griffithの考え方を引用して説明された. 観察結果は, この反応の活性化エネルギー, 156-158kcal/molが, シリコン粒子表面に, 反応により形成された窒化物皮膜中を窒素が拡散する際の障壁に相当するものであろうとする考え方を支持するようなものであった.

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導伝電流に対する, 誘電損失電流の割合を評価した結果, 大部分の酸化物ガラスにおいて後者は前者に較べてまったく小さいことが明らかになった. 特に内部摩擦の混合アルカリピークに対応する誘電損失電流は導伝電流の数パーセントにすぎず, このためそれを交流ブリッジで検出することはできない. しかし, このような誘電損失電流も吸収電流法によれば検出可能になる. このため酸化物ガラスの誘電緩和測定のための吸収電流法の適用が詳細に検討された. 内部摩擦の高温ピークの場合, 期待される誘電損失電流は, 導伝電流に較べて極端に小さい. このことは高温ピークが電気的に活性なものであるかどうかにかかわらず, 誘電緩和としては観察できないものであることを意味する.

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多孔質ガラスの逆浸透圧法による塩水の脱塩率を高める目的で, コーニング社製多孔質ガラス管の外側の面に薄いセルロースアセテート膜をコーティングし, この複合多孔質ガラス管の脱塩作用を調べた. この結果, 同一圧力, 塩水濃度において複合多孔質ガラス管は多孔質ガラス管のみの場合よりも高い脱塩率が得られた. これは複合多孔質ガラス管と塩水との界面の水分子層の厚みが多孔質ガラス管と塩水との界面のそれよりも厚くなった為と思われる. 脱塩率は, 1) 0.25wt%から0.05wt%塩水濃度範囲内で低い塩水濃度のほうが高くなり, 2) 300psiまでの加圧条件で圧力が高くなると高くなる. この複合多孔質ガラス管は2段階海水脱塩法における低濃度塩水の純水化に使用され得ると思われる.

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不純物としてPdを用い, NbOホイスカーを, 1200-1350℃の温度範囲で, 水素, 水蒸気, 五塩化ニオブ, アルゴンの四成分系から気相成長させた.
良質のホイスカーを得るための最適条件はNbCl₅: 2.8-5.1vol%, H₂: 33-66vol%, H₂O: 0.45-2.2×10^-3vol%であった. ウール状のホイスカーは比較的低濃度のH₂OまたはNbCl₅の領域で得られ, 一方ピラー状ホイスカー (平均長さ1mm, 直径2μm) は比較的高濃度のH₂OまたはNbCl₅の領域で得られた. 柱状ホイスカーは早い “VLS” 機構に続いて, 遅い “VS” 機構により成長するものと考えられた.

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