純C₃Sの精密熱測定および高温X線回折により, 常温から1500℃の間に10個の変態が存在することを認めた.
新しく確認した4個の変態は, すべて三斜晶系に属する. 各変態の転移熱およびそれらが存在する温度領における比熱を定めた.

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The kinetics of the crystallization of fluor-richterite and a layer-structure crystalline phase from the glass as poured (S 000), the phase separated glass (S 600) and the partly crystallized glass (S 625) were studied by a quantitative X-ray powder diffraction method. The following results were obtained:
1) The crystallization of fluor-richterite occured in the temperature range between 638°C and 1100°C and the largest amount of fluor-richtrite was observed in the heat-treated sample at 1000°C. The rate of the crystallization in S 600 was larger than those in S 000 and S 625.
2) The crystallization of a layer-structure crystalline phase occured in the temperature range between 600°C and 700°C. The amount of the crystalline phase increased with heating time at a constant temperature in the earlier stage and decreased in the latter stage of crystallization. The largest amount of the crystalline phase was observed in the heat-treated sample at 663°C for 2hr. The rate of the crystallization was larger in S 600 than those in S 000.
3) The analisis of X-ray powder diffraction data using Johnson-Mehl-Avrami equation showed that the rate of crystallization of each crystalline phase at the temperature under 700°C depended on the nucleation rate of each phase.
4) The activation energy of nucleation of fluor-richterite and a layer-structure crystalline phase ware 110-164kcal/mole and 88kcal/mole, respectively.

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Ca₂SiO₄の変態であるα, α'およびβ型について適当な安定剤を用いて単結晶を合成し, ラウエ工法, ワイセンベルグ法等によりその回折上の特徴から, これらの結晶の特質を検討した.
α型は6回対称ラウエ写真から六方格子と考えられ, Bredigによるglaseriteと同形な三方格子とは大きくことなっている. 著者らが合成したものはV, P, Baなどの安定剤をかなり多く置換しなければならないが, これらは高温X線回折によると純粋なα-Ca₂SiO₄と連続的な固溶関係をもつ. Pを置換したα型結晶相の格子の大きさはa=5.401Å, c=7.144Åであった。
Ba, Sr, B, Vその他により合成したα'型は, Douglasがスラグから採取したものと同周期の軸長をもつ. 著者らはこれが単位格子として最小の大きさであることを確認し, その空間群はCmc2₁であった. クリンカー中のα'型結晶も合成物と全く同様なX線回折を示し, 同様な構造であることを認めた. Srにより合成したα'型の格子の大きさはa=11.091Å, b=18.683Å, c=6.829Åであった.
β型は多くの安定剤により簡単に合成できる. これらもMidgleyが合成単結晶を用いて結晶解析を行なったものとはことなり, a, c軸が2倍の周期をもち, またこれはクリンカー中のβ型についても全く同様であった. A1により安定化したβ型の格子恒数はa=11.067Å, b=6.746Å, c=18.575Å; β=94.40°であった。
α, α'間の構造上の相違はβ, α'間の相違よりも大きいことが推察された. これは示差熱分折による前者のより大きな熱変化と, ラウエ写真, 赤外吸収スペクトルの前者の大きな相違により考えられた.
β, α'間のウラエ写真はβの2回軸生成のためのわずかな回折点強度の相違が見られるみで, 相互のごくわずかな格子の変移により小さな熱変化をともなって移行できると考えられた.

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Creep behavior of some nickel-zinc ferrites was measured in a temperature range from 900°C to 1200°C. The results were as follows.
1) Deformation of creep of nickel-zinc ferrites proceeded in accordance with the lattice diffusion mechanism which was suggested by C. Herring.
2) The relation between ε (strain rate) and σ (stress) in creep of nickel-zinc ferrites was expressed by an empirical equation
ε∝σ^1-1.25
It was reasonably concluded that the difference between the above experimental equation and Herring's equation was caused by small cracks to be generated during the creep test rather than dislocation movement and or grain boundary slip.
3) Activation energy of creep of nickel-zinc ferrite was 120±10kcal/mol. This value showed good agreement with activation energy of 115kcal/mol for diffusion of iron ion in nickel-zinc ferrite which was obtained from a direct measurement by S. Ogawa.
4) Diffusion coeffient obtained from creep measurement was 10^-13 to 10^-10cm²/sec in a temperature range from 1000°C to 1200°C.

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One of carbon fibers commercially available in Japan is produced by Kureha Chemicals Co. from the pitch which is a by-product of a thermal cracking of crude oil. This fiber was heat-treated at 1300°C, 1500°C, and 2000°C for an hour and voids existing in the original fiber and heat-treated ones were investigated by X-ray small angle scattering. And the following results were obtained;
1) There was almost no void in the commercially available original fiber with the nominal heat-treatment temperature of 1000°C.
2) With increase of heat-treatment temperature of this original fiber, increased voids or the region intensity of carbon atoms of which was so small that these parts could be regarded substantially as voids.
3) Radius of gyration of the sample heat-treated at 2000°C was calculated as 13Å along equator and 11-18Å along meridian.
4) Even helium gas could substantially not penetrate into these voids.

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