The electrical conduction and dielectric relaxation of some glasses in the system Na₂O-Fe₂O₃-P₂O₅ were studied over the temperature range 20°-180°C. This system contains Na₂O which confers an ionic conductivity on glass and Fe₂O₃ an electronic conductivity.
The conductivity of this kind of glass may be expected to have an additive property from which it can be calculated by the addition of ionic and electronic conduction. In this study the experimental results were discussed in view of the additive property. Samples used in this experiment were prepared by melting under different conditions, i.e. in the air and in a reducing atmosphere. The ratio (Fe²⁺/Fe²⁺+Fe³⁺) in the glass was determined by chemical analysis. The conductivity was observed to vary greatly with the melting temperature. The values of log σ increase with increasing Fe²⁺ ion in the glasses of compositions 40Fe₂O₃-60P₂O₅, 10Na₂O-30Fe₂O₃-60P₂O₅, 20Na₂O-20Fe₂O₃-60P₂O₅; but on the contrary in the galss containing relatively small amount of Fe₂O₃, 30Na₂O-10Fe₂O₃-60P₂O₅, the log σ decreases with increasing Fe²⁺ ion. This can be considered from the fact that the mechanism of hopping theory holds for the glass containing a large amount of Fe₂O₃ and does not hold for the glass with small amount of Fe₂O₃ content. The d.c. conductivity (σ) of glasses of the formula xNa₂O-(40-x)Fe₂O₃60P₂O₅ was shown by replacing Fe₂O₃ with Na₂O to have a minimum value at the composition near x=20 at temperature above 100°C, but at temperature below 100°C the x-value showing the minimum conductivity was seemed to shift toward its higher value. The activation energies ΔH_dc and ΔH_ac were found to be grouped into two parts, the higher values in the compositions near (40Na₂O-60P₂O₅) in which ionic conduction predominate and the lower values in the compositions near (40Fe₂O₃-60P₂O₅) in which electronic conduction predominate.
The dielectric relaxation was observed by changing frequency and temperature. The values of dielectric constant ε′ and dielectric absorption ε″ were measured in glasses melted by various conditions.
The normalized dielectric losses at various temperature was shown by plotting ε″/ε″_max against log (f/f_max) but it was independent of temperature. The relationship between σ and the frequency at which the dielectric loss becomes maximum, f_max, was found to follow the equation proposed by H. Namikawa.

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Temperature dependences of thermal conductivities and heat capacities for As₂S₃ and As₂Se₃-glasses were measured by continuous heating method in the temperature range from the room temperature to the transition temperature range. The following conclusions were obtained.
(1) By continuous heating method, thermal conductivities and heat capacities were measured easily and in a short time.
(2) Thermal conductivities of these glasses increased slowly with rising temperature and, above the transition range, the conductivities slightly decreased with increase of temperature.
(3) Heat capacities of these glasses increased with rising temperature, and in the transition range the temperature dependence showed a sudden change and had a maximum.
(4) Temperature dependences of specific heats were determined from the observed heat capacities and specific gravities.
(5) The contribution of radiation heat transfer to the total heat transfer was estimated. It is reasonable to consider the heat to be transfered only by conduction, since the contribution of radiation was negligible small in the present work.

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By using a precipitation method from homogeneous solution, very small amount of ²³⁵UO₂ was homogeneously mixed with less sinterable BeO powder derived from beryllium hydroxide. The BeO-²³⁵UO₂(17ppm) compacts were irradiated by thermal neutrons in a reactor (KUR). The sintering behaviour of the compacts was largely different from that of pre-irradiated compacts.
The results obtained were summarized as follows;
(1) The post-irradiated compacts began to shrink at higher temperature than the preirradiated compacts. It was supposed that this phenomenon was due to some consolidation of particles caused partially by the irradiation sintering.
(2) The post-irradiated compacts sintered rapidly once they began to shrink. It was supposed that this phenomenon was due to enhancement of diffusion of constructing ions when their defects caused by so-called fission fragment damage recovered at high temperature. Namely, this shows that internal defects in powder particles affect largely the sinterability of their compacts.
(3) Irradiation damages were recovered during relatively short time period at such a high temperature as in this experiments. The effects of the irradiation were, therefore, little appreciated in the later-stage sintering.

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Two types of silver chloride photochromic glasses, one based on the Na₂O-B₂O₃-Al₂O₃-SiO₂ system (Glass I) and the other on the Li₂O-Na₂O-B₂O₃-Al₂O₃-SiO₂ system (Glass II), which were prepared by precipitating AgCl crystals at high temperatures of 560°-580°C, have been reheated at low elevated temperatures ranging from 200° to 520°C, and ultraviolet induced darkening has been measured. It was found that the reheating markedly affected the darkening characteristics of the photochromic glasses and the effect varied with their base composition and thermal history of the glass. Generally, the degree of darkening of Glass I lowered as a result of reheating, regardless of the reheating temperature. Especially, it lowered to the value as low as 50% of that before reheating when the glass was reheated around 520°C. On the other hand, a pronounced increase in the degree of darkening, reaching 100-200% sometimes, occurred when some samples of Glass II were reheated at the temperatures in the range 300°-420°C. No increase in the degree of darkening was seen in Glass II, however, when the condition of heating for precipitation of AgCl crystals was different and the degree of darkening before the reheating was already high. The rate of fading of U. V. -darkened photochromic glasses was also affected by the lower temperature reheating.
The occurrence of these variations of photochromic characteristics resulting from the heating at low elevated temperatures seems to indicate that the “AgCl” particles precipitated in glasses are actually mixtures or solid solutions of AgCl and NaCl (or LiCl) and that the reheating alters the state of solid solution within the particles.

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The mixture of silica powder and milk of lime was stirred in an autoclave and treated hydrothermally under the following conditions; molar ratio of CaO/SiO₂ 0.975, weight ratio of water/total-solid 12, pressure 12kg/cm², temperature 191°C, for 4-8hrs. Thus milky slurry consisting of xonotlite was prepared.
The slurry contains 8% of total solid matter and its viscosity is 2.0-2.3 poise. Crystals are almost xonotlite and small amount of tobermolite co-exists. Grains are spherical aggregates with 5-80μm diameter having inter-twining structures of needle-like or sticklike xonotlite crystals, as shown in Figs. 4, 5 and 7.
The slurry is easily dehydrated and shaped in a mold under pressure and the molded material can be hardened only by drying. The properties of thus obtained light molded material are following as shown in Table 1; density 0.2, bending strength 5-10kg/cm², thermal durability 1000°C, shrinkage at 1000°C 0.7-1.5%.

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Heats of immersion of alkali and alkaline earth metaphosphates in some aromatic hydrocarbons were measured with a twin microcalorimeter to investigate the interaction of the interfaces between the phosphates and the hydrocarbons.
The heats of immersion in benzene for the phosphates with long chains were lower than those for the phosphates with short chains. The dependence of heat of immersion on chain lengh is attributed to the change in the concentration of the hydroxyl groups, which can interact with π-electron of benzene, with an increase of chain length.
The heats of immersion in benzene increased with an increase in polarizing power, z₊/r₊² (where z₊ is the number of positive charge and r₊ the ionic radius), of the cations of the phosphates. This variation is considered to be interpreted in terms of the polarizing effect of the phosphate surface on benzene molecules. The relatively high values, especially of lithium metaphosphate, suggest that the acid-base interaction between the surfaces of the phosphates and benzene may contribute to the heat of immersion.
In order to examine the effect of substitution of methyl group, the heats of immersion of lithium and sodium metaphosphates in benzene, toluene and p-xylene were measured. The heat decreased with an increase of the number of the substituent. It is not clear at the present stage that which the predominant factor is, the electron donor strength or the steric factor of the aromatic hydrocarbon.

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AlN powders were synthesized from high pure Al₂O₃ with reducing agent of high pure carbon in azotic atmosphere. Obtained powders were adequately pure in metalic impurities when the nitriding processes were proceeded in high temperature such as above 1800°C.
Oxygen in the powders were measured by the fast neutron activation analysis. These powders contained 1.5-7.2wt% of oxygen. The impurity oxygen contents which greatly influenced upon the properties of the powders could be regulated by the temperature of the synthesizing reaction.

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