Coordination analysis of Al using AlKα shifts and profile changes was studied by measuring of AlKα of several Al compounds with a high resolution two-crystal spectrometer. A method was established to discriminate mixed coordinated state Al from simply coordinated state Al by means of profile changes and shifts of AlKα. The shift of Kα for 5-coordinate component of Al in andalusite and the result of molecular orbital analysis revealed that the energy of AlKα from 5-coordinated Al occupies an intermediate region between 4-and 6-coordinate regions. Based on these shift data, the following results were obtained. Sillimanite has 6-and 4-coordinated Al instead of 5-coordinated Al, CaO⋅6Al₂O₃ has 5-and 6-coordinated Al with dominant 5-coordinated Al. Peak separation by a non-linear least square method had proved to be useful for quantitative coordination analysis.

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R₂O-TiO₂ (R=Rb, K, Na) and BaO-TiO₂ binary glasses have been prepared by the splat quenching method to determine the glass formation region. The oxygen co-ordination number of Ti⁴⁺ was estimated by both infra-red (IR) and photoacoustic spectroscopies (PAS). Glass formation region identified by electron diffraction extended with increasing estimated cooling rate. PAS spectra of these glasses may be more sensitive to the co-ordination number of Ti⁴⁺ than IR spectra. The ratio of oxygen 4-fold coordinated Titanium ion (Ti⁴⁺(4)) oxygen 6-fold coordinated Titanium ion (Ti⁴⁺(6)) could be determined from the computer analysis of PAS spectra. Ti⁴⁺(4) and Ti⁴⁺(6) were co-existent in binary titanate glasses, and the ratio Ti⁴⁺(4)/Ti⁴⁺(6) may be determined by the basicity of glasses, that is, the fraction of Ti⁴⁺(4) were increased with increasing the basicity of glasses. It was concluded that the fraction of Ti⁴⁺(4) in these glasses depended on the basicity parameter using the ionic potential of cation in basic oxides.

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Porous membranes were prepared from fine particles of synthetic water-swelling fluoromica. The pore structure of membrane was studied by scanning electron microscopy and mercury penetration method. Permeability was determined for several gases under different pressures, and discussed in connection with the pore structure. Four kinds of pores, i.e. 7×10⁴, 2×10⁴, 3×10² and under 4nm as the maximum diameters were observed in the membrane. Permeation properties were represented well by the intermediate state equation between Knudsen and viscous flow. The hydraulic radius of the membrane, estimated by introducing experimental factors of He to the intermediate state equation, was 150nm. Separability of He/Ar decreased at high pressures owing to collision between different gas molecules (Present-de Bethunes' effect) and viscous flow. The separation factors which were determined by experiment agreed with the one predicted from the Present-de Bethunes' equation, assuming the pore radius is 80nm.

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Porous glass prepared by acid leaching of phase-separated sodium borosilicate glass usually contains colloidal silica particles which originate from the silica component of the borate phase. When the colloidal silica fills the pores in the silica skeleton, the pore volume is reduced and the mass transport through the porous glass is prevented. In order to obtain the porous glass with high pore volume, the effects of the sample diameter and the concentration of leaching acid on the formation of colloidal silica were studied. With decreasing sample diameter, the dissolution of silica during leaching increased and the precipitation of colloidal silica decreased, and accordingly the pore volume increased. Similarly the pore volume increased with decreasing concentration of the leaching acid. By washing with acid solution both colloidal silica and the skeleton were dissolved, and the pore volume increased. These results indicate a method to obtain porous glass with high pore volume.

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Abrasion of returnable bottles during transportation on conveyors in a bottling hall was investigated, using conveyors for experimental use. Using test bottles, the weight of which is ca. 605g, the experiments were carried out, by running them on these conveyors repeatedly at a certain speed, and the grade of abrasion on their outer surface was quantitatively investigated. At the same time, frequency analysis and sound pressure level of noise generated were also investigated from the accoustic standpoint. Finally, the relationship between abrasion grade, sound pressure level and running speed of bottles was investigated. The results obtained are summarized as follows:
(1) In the case of leight abrasion (scuffing), a linear relationship was obtained between running speed and the distance of transportation in logarithmical unit at a same abrasion grade level.
(2) In the cases of heavy abrasion (Herztian crack), the diameter of which is under 1.5mm, impact energy of lower limit was found to be ca. 0.3 Joule.
(3) A linear relationship was obtained between running speed and sound pressure level.

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Spreading of glass frits on alumina substrate for hybrid IC applications has been studied. A PbO-SiO₂ binary glass containing 75% PbO was chosen as a typical composition and Al₂O₃, ZnO, MgO and B₂O₃ were added thereto. In addition to alumina substrate containing 96 and 99% Al₂O₃, sapphire and fused SiO₂ plates were used for comparison. The spreading was determined from the area of glass frit on the substrates as a function of heating time and temperature. The reaction was examined by microscopy and EPMA. The results are summarized as follows.
(1) The spreading increased with increasing temperature and time for all the glass compositions. The spreading was promoted by ZnO and MgO addition but suppressed by Al₂O₃ and B₂O₃ addition.
(2) All the additives increased the thickness of the reaction layer, most pronounced With ZnO, followed in the decreasing order, by Al₂O₃, MgO and B₂O₃. ZnAl₂O₄ was the only crystalline product observed in the reaction.
(3) Comparison of spreading behavior on different substrates indicated that the contribution of glass-substrate interactions to the spreading depends on the glass composition.

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The manufacturing process of Mn modified Pb(Sn_1/2Sb_1/2)O₃-PbTiO₃-PbZrO₃ ceramics was investigated to get pore-free piezoelectric ceramics with fine grains and less fluctuation in the electrical properties for surface acoustic wave filters. These were obtained when fired in an oxygen atmosphere. In the solid state reaction of the composition, a pyrochlore compound Pb₂SnSbO_13/2 was observed as an intermediate phase, which suppressed the grain growth and generated spherical. The polished surface of the ceramics was satisfactory for 90MHz interdigital transducers of 6.7μm finger width to be fixed. The longitudinal wave and the SAW velocities of the ceramics increased by 20m/s (0.8%) and 27m/s (1.1%), respectively compared with those fired in air. The fluctuation of SAW velocity σ/x was less than 0.10% in a wafer and 0.15% in a firing lot. The attenuation of surface acoustic wave in the frequency range below 90MHz depends on the internal friction.

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The iron leaching by acid treatment of Shirasu, glassy volcanic ash abundant in South Kyushu, has been studied in an attempt to convert it into a ceramic raw material. The effects of leaching temperature and particle size of Shirasu were studied. The rate of leaching was high in the early stage, levelling off with time. The amount of leached iron increased with increasing acid concentration and was highest with HCl, followed by H₂SO₄ and HClO₄ in the order stated. The rate of leaching increased with increasing temperature but no tempeature effect was observed after the extended heating. The reduction in particle size resulted in the enhanced iron leaching and also in the dissolution of Shirasu particles. The surface area, determined by the BET (N₂) adsorption method, increased with increasing leaching time. The residual iron content after leaching was not reduced below 0.9wt%, probably because of the inert nature of glassy particles.

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Absorption spectra of Cu²⁺ ions in PbO-SiO₂-CuO and PbO-SiO₂-K₂O-Na₂O-CuO glasses were measured, and the relation between composition and absorption peak wave number of Cu²⁺ was studied. The peak position shifted toward the higher wave numbers with increasing [PbO]/[SiO₂] ratio in PbO-SiO₂-CuO glasses. The mixed alkali effect given to the peak wave number in PbO-SiO₂-K₂O-Na₂O-CuO glasses depended on the [PbO]/[SiO₂] ratio. The peak position at [PbO]/[SiO₂]=0.64 shifted toward the lower wave numbers with increasing [K₂O]/[K₂O+Na₂O] ratio. The peak position at [PbO]/[SiO₂]=1.0 also shifted toward the lower wave numbers with increasing [K₂O]/[K₂O+Na₂O] ratio and the minimum was found at [K₂O]/[K₂O+Na₂O]≈0.7. At [PbO]/[SiO₂]=1.5, the minimum was found at [K₂O]/[K₂O+Na₂O]≈0.35. The mixed alkali effect was most distinct at this ratio. The relation between glass composition and refractive index in PbO-SiO₂-K₂O-Na₂O-CuO glasses was studied. No mixed alkali effect was found in the refractive index. The refractive index shifted linearly toward the lower values with increasing [K₂O]/[K₂O+Na₂O] ratio.

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The sintering of MgO with ZrP₂O₇ additions in the concentrations of 0.1, 0.5, 1.0 and 3.0mol% was studied in the presence of the liquid phase at increasing temperatures (room temperature to 1450°C) and at a constant temperature (1450°C, 5h). The densification of the MgO compact was inhibited above 1300°C by the addition of 1.0mol% or less of ZrP₂O₇, whereas it was promoted by 3.0mol% ZrP₂O₇ addition. The difference in the densification behavior was considered to be due to variations in the amount of the liquid phase present in the MgO-Mg₃(PO₄)₂ system above 1300°C: an amount of the liquid phase sufficient to spread over the grains promoted the densification of the MgO compact through accelerating the rearrangement of the grains and through eliminating the open pores.

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