This report concerns with the manufacturing methods of polymer-impregnated bricks which are employments of styrene and methyl methacrylate as monomers, of triallyl isocyanurate as polymerization promoter and of azobisisobutylonitrile as polymerization initiator.
The peak temperature during polymerization in the course of manufacturing polymer-impregnated bricks was automatically measured by inserting thermocouples in the test pieces.
And the relationship between the temperature and physical properties of the bricks manufactured has also been reported.
Impregnants having the following compositions (by weight) were used in the manufacturing of the bricks.
(1) styrene: azobisisobutylonitrile 99:1
(2) methyl methacrylate: azobisisobutylonitrile 99:1
(3) styrene: methyl methacrylate: azobisisobutylonitrile 49.5:49.5:1
(4) styrene: methyl methacrylate: triallyl isocyanurate: azobisisobutylonitrile 44.5:44.5:10:1
Impregnation into bricks was undertaken by methods of atmosphering and deairation.
Rate of polymerization was found to be the factor influenced most by the peak temperature to be raised.
Under the experimental conditions of this study, triallyl isocyanurate proved to be a very effective polymerization promoter when it was used in amounts more than 4%.
The result of flexural strength indicated there might be some bonding strength between the polymerized impregnant and the bricks as base materials, but more testings into further details would be necessary to conclude the said phenomenon.
Water absorption is remarkably decreased by little addition of the impregnant, but the fact is obtained that further addition of the impregnant makes no noticeable change in the water absorption. Thus, it seems that water absorption is primarily affected only by the polymer impregnated on the surface layer of the test piece.

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The D. C. conductivities of lead borate glasses containing Fe₂O₃ or CuO were measured in the temperature range from 100 to 300°C, and the conduction mechanism was discussed in terms of the oxygen coordination of the transition metal ions. The glasses containing 2.5-25mol% Fe₂O₃ or 10-50mol% CuO were prepared by melting at 1000-1200°C and quenching in air. By chemical analysis, the fraction of reduced Fe ion and of reduced Cu ion was determined to be 5-10% and 2-25%, respectively.
These glasses were inferred to be electronic conductors because the D. C. polarization was not observed and the activation energy for conduction roughly agreed with those of transition metal phosphate glasses known as electronic conductors. Increase in Fe₂O₃ or CuO content and in the molar ratio of PbO to Fe₂O₃ made the conductivities of these glasses increased. The conductivities of Fe₂O₃-containing glasses were about 10³ times as large as those of CuO-containing glasses.
Emission X-ray spectra showed that the Fe ions in these glasses were in 4 and 6-coordinated, and that the Cu ions were 6-coordinated. The compositional dependence of the conductivities and of the concentration of the 4-coordinated Fe ion suggested that the 4-coordinated Fe ion was mainly responsible for the conduction of Fe₂O₃-containing glasses.
From the evidence that the tunneling factor, obtained from the conductivity using Mott's equation, approximately agreed with that estimated from charge transfer band, it was elucidated that the electronic conduction of Fe₂O₃-containing glasses was caused by the non adiabatic small polaron hopping process. Mott's equation was not applicable to the conduction of CuO-containing glasses.

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Chert rock (quartz A), sand stone (quartz B) and metamorphic rock (quartz C) were chosen as sample. The materials were ground, extracted by hydrochloric acid, next washed with water and dried, and then mixed with calcium hydroxide in a molecular ratio CaO/SiO₂ of 0.8.
Hydrothermal reactions on the sample were carried out in an autoclave for 0.5, 1, 2, 4, 6, 8 or 16h at the temperatures of 160 and 180°C. The rate of reaction was given from the ratio of combined lime and silica to the total lime and silica, and the values t/t_0.5 were obtained from each reaction rate. The comparison between these observed t/t_0.5 and calculated t/t_0.5 by the expression [1-(1-α)^1/3]ⁿ=K(t/t_0.5) gives us the conclusion that the hydrothermal reaction is controlled by the diffusion of CaO in the lath phase that has high CaO/SiO₂ ratio.
In the early stage of reaction, the fiber or lath like tobermorite was formed in every samples. After 2 and 4h of reaction, the leaf-like crystal was formed in sample A and the plate-like crystal in sample C. But in sample B only lath and fiber like tobermorite was formed.
The compressive strengths were tested for the autoclaved cylindrical test pieces. The quartz A, that produce the leaf crystal gives the greatest strength, and the quartz C that produce the plate-like crystal gives lower strength than the former. The quartz B that delays the reaction gives lower effect in increasing the strength.
It is concluded that the effect on the strength is attributed to the reactivity of quartz and crystal shape of the produced phases. The reactivity of quartz in the order of C>A>B showed a close relation to the order of heat of wetting values, B>A>C, which is resulted presumably from the degree of lattice distortion.

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Non-crystalline, transparent films of the TiO₂-, ZrO₂-, and TiO₂-ZrO₂-SiO₂ systems were prepared from metal alkoxides. Alkali resistance, refractive indices and infrared spectra of the films were measured. The effect of Ti⁴⁺ and Zr⁴⁺ ions on the improvement of alkali resistance was investigated.
Refractive index of the films increased with heating temperature reaching a constant value in the films heated at the temperature higher than about 500°C. It also increased almost linearly with increasing amount of TiO₂ or ZrO₂ content in the TiO₂-SiO₂ and ZrO₂-SiO₂ binary systems. Substitution of TiO₂ or ZrO₂ for SiO₂ was effective to the improvement of the alkali resistance of the films, especially the effect of ZrO₂ was remarkable. In the infrared spectra of TiO₂ containing films, the absorption band, which could be assigned to Si-O-Ti bond, was clearly observed at about 920cm^-1. After immersion in 3 N-NaOH solution, the intensity of the absorption band due to Si-O-Si bond decreased more than that due to Si-O-Ti bond in the films of TiO₂-SiO₂ system. On the other hand, any selective decrease of particular absorption bands was not found in the ZrO₂ containing films.
On the basis of the experimental results, it was considered that Ti⁴⁺ ions were very likely on the sites equivalent to those of Si⁴⁺ ions forming Si-O-Ti bonds, while Zr⁴⁺ ions occupied the interstices of the SiO₄ networks.

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OK and BK band spectra of some simple oxides and their molten mixtures were measured by an electron probe microanalyzer (EPMA) with a special attention to the characterization of the heterogeneous and glassy materials. OK spectra of PbO, B₂O₃ and SiO₂ changed in spectral features with excitation voltage when they were coated with beryllium at about 1×10^-4 Torr. When they were coated with carbon instead of beryllium at 1×10^-4 Torr or with beryllium at about 2×10^-5 Torr, OK spectra did not show any clear changes in features with the excitation voltage. Then it was considered that the formation of BeO during the evaporation in a low vacuum was the major cause for the spectral changes. Any significant differences were not observed in OK spectra of SiO₂ among all the crystalline forms. OK spectra of binary molten mixtures were the averaged ones of component oxides. BK spectra of oxides accompanied satellite bands at the both sides of the main band and these satellite bands showed distinct changes in features with chemical combinations in molten mixtures. PbO-B₂O₃ system showed remarkable changes in spectral features such as the intensity and wavelength of satellite bands and the width of the main band depending on the mutual concentrations of the components. It was found that the strong intensity of the high energy satellite band was characteristic to the B₂O₃-SiO₂ system and the small intensity of the high energy one was to PbO-B₂O₃ system.
These spectral changes in features among oxides and binary molten mixtures were used for the microanalysis of the molten mixture of PbO⋅1.8B₂O₃⋅3.2SiO₂ in which a phase separation was clearly observed. It was found by the X-ray elemental and microscopic analysis that the bright field region in the secondary electron image of the fracture, surface of the sample corresponded to the region rich in PbO and the dark field to the one rich in SiO₂. The BK spectra were measured at each region and the spectral features were compared with those of oxides and binary molten mixtures. It was presumed that some PbO-B₂O₃ compound was formed in the bright field region and that B₂O₃⋅SiO₂ was formed in addition to SiO₂ as a major component in the dark field region.
It was concluded that the microanalysis of heterogeneous and glassy or amorphous materials by an EPMA was especially useful for the characterization of materials in microregion in combination with the conventional X-ray elemental and microscopic observation and the valence or chemical state analysis by ultrasoft X-ray emission band spectra.

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The rate of dissolution of zircon refractories in molten slag of polycomponent system was studied by rotating the cylindrical specimen at a constant speed of 100rpm in a stationary crucible containing the molten slag at 1500°C.
The dissolution rate V(cm/s) in slag in the ternary system FeO-CaO-SiO₂ (CaO/SiO₂=1) decreased remarkably with decrease in FeO content F(100wt%=1) of slag, and the relation between V and F was given by logV=1.9F-4.4 in the range of 10-90% FeO.
In slag in the four component system 20%FeO-CaO-SiO₂-10%MgO and in the five component system 30%FeO-CaO-SiO₂-10%MgO-10%Al₂O₃, the dissolution rate depended on the basicity of slag, especially the dissolution rate in the latter passed through the maximum at the basicity around 3.

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When a Y₂O₃ sintered body was heated at above 1800°C in a H₂ (d.p. -36°C) atmosphere, it became black. It is said that blackness is due to a color center (F-center). In this work the blackness was investigated.
Y₂O₃ sintered pieces were heated at 2000°C in a H₂ (d.p. -36°C) atmosphere for 5, 15 and 25min, respectively. Spectroscopic properties of the black piece were measured at the wavelength of 0.2-2.6μm.
Y₂O₃-0.1mol%Eu₂O₃ green compacts were sintered at 2270°C. One of the sintered pieces was heated at 2000°C for 15min in a H₂ (d.p. -36°C) atmosphere to make it black. Thermoluminescence of these pieces was measured at -195.8-20°C.
Peaks of absorption were found at the wavelength of 458, 524, 646 and 2240nm for the black Y₂O₃ pieces.
Thermoluminescence of Y₂O₃ pieces was not detected. However, a glow was found at about 210K for a black Y₂O₃-Eu₂O₃ piece. The glow suggested that a black Y₂O₃ piece had such a structural defect as an oxygen vacancy. Depth of the trap level due to the structural defect was 1.478eV.

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