Potassium titanate fibers were grown from the K₂O-TiO₂ system in fluxes of K₂MoO₄ and K₂WO₄. The basicities of flux melts were controlled by adding K₂O as a basic component, and MoO₃ or WO₃ as an acid one.
When starting compositions are represented by the formula (K₂O)_x⋅TiO₂, potassium hexatitanate (K₂Ti₆O₁₃) in the form of colorless acicular crystals were usually synthesized with less than x=1/6 in the K₂MoO₄ flux melt, and with less than x=1/7 in the K₂WO₄ flux melt. Mixtures of potassium hexatitanate and tetratitanate (K₂Ti₄O₉) in the form of colorless bundle fibers were always obtained with more than these x values.
The solid-liquid interface reaction is predominant at the earlier stage of the flux reaction, followed by the recrystallization reaction at the later stage. Consequently, the growth rate and shape of short fibers at the earlier stage were markedly affected by the size of TiO₂ particles, and a supersaturation needs to be controlled to grow long fibers. Fibers of the mixed phase of K₂Ti₆O₁₃ and K₂Ti₄O₉ obtained by the slow-cooling method reached up to 5mm in average length (maximum 10mm).

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Crystallization of beryllium metaphosphate glass powders in size from 44 to 74μm was studied with a high-temperature X-ray diffractometer.
1) Crystalline phase formed in the glass during heating above 600°C is a high-temperature polymorph of beryllium metaphosphate. It transforms into α-Be(PO₃)₂ reversively.
2) The so-called “β-Be(PO₃)₂” described in ASTM card was never crystallized out of the glass. It is found that the crystal is not a polymorph of beryllium metaphosphate but has a chemical composition of BeO:P₂O₅:H₂O=1:1:1.
3) Spherulite formed in the blown film glass shows periodic extinction rings when viewed under a polarization microscope, indicating twisting of the lamellas.
4) From J-M-A plot of the crystallization data, Avrami exponent m=4 is obtained through overall crystallization. This indicates the thermal nucleation and the three dimensional growth. The apparent activation energy for the crystallization is ca. 70kcal/mol.

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Chemical shifts of AlK_α fluorescence X-ray peaks of Na₂O-Al₂O₃-SiO₂ and Li₂O-Al₂O₃-SiO₂ glasses with the Al₂O₃/R₂O ratio (R₂O=Na₂O or Li₂O) varying between 0.25 and 1.50 have been measured. The chemical shifts for all the glasses were almost identical with that of fourfold-coordinated Al³⁺ ions in orthoclase, indicating that the Al³⁺ ions in these glasses are fourfold-coordinated by oxygen ions and almost no sixfold-coordinated Al³⁺ ions occur. This means that the concept that sixfold-coordinated Al³⁺ ions occur in alkali alumino-silicate glasses with the Al₂O₃/R₂O ratio larger than unity should be modified. The chemical shift of the AlK_α peak of 16Na₂O⋅24Al₂O₃⋅60SiO₂ glass has not exhibited much change when the glass was subjected to compression at 50kbar at 25°C and 500°C, indicating that no change of coordination number of Al³⁺ ions from 4 to 6 is caused by the pressure of this range.

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The formation of fine zirconium nitride powders by the vapor phase reaction of ZrCl₄-NH₃-H₂-N₂ system was studied between 1000°C and 1500°C. The thermal decomposition of ZrCl₄-NH₃ adducts was also investigated. The following results were obtained.
1) ZrCl₄-NH₃ adducts decomposed to zirconium nitride in the stream of NH₃-H₂ mixture at above 750°C. The particle size of zirconium nitride powders produced was from 0.2 to 2μm. The atomic ratio N/Zr of these nitrides was 1.13 at 900°C and 1.04 at 1200°C.
2) The vapor phase reaction of ZrCl₄-NH₃-H₂-N₂ system gave powder products consisting of zirconium nitride with particle size below 0.05μm and hydrolyzable intermediate compounds. The content of zirconium nitride increased remarkably with increasing the mixing temperature of ZrCl₄ and NH₃ vapors or the reaction temperature, but was below 80wt% under the present reactoin conditions. For the formations of zirconium nitride particles, two processes are proposed depending on the mixing temperature of ZrCl₄ and NH₃ vapors. One of them is the formatoin of an adduct-particle from ZrCl₄ and NH₃ and its thermal decomposition into the nitride (at low mixing temperatures), and another is the nucleation of zirconium nitride and its growth (at high mixing temperatures).
3) The lattice constant of zirconium nitrides prepared increased from 4.557 to 4.570Å with the elevation of reaction temperature.

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Measurements have been made of the heats of solution in 0.2N HNO₃, of the glassy borates R₂O⋅6B₂O₃, R₂O⋅4B₂O₃ and R₂O⋅3B₂O₃, where R were lithium, sodium and potassium. An isoperibol solution calorimeter was used. Heats of solution have also been measured for glasses of (R₂O+R′₂O)⋅nB₂O₃, where R and R′ were different cations and n=6, 4 and 3. The heats of mixing, i.e., the enthalpy changes of the processes x[XR₂O⋅(1-X)B₂O₃]+(1-x)[XR′₂O⋅(1-X)B₂O₃]→X[xR₂O⋅(1-x)R′₂O](1-X)B₂O₃, were obtained by subtracting the observed heats of mixed alkali glasses from the weighted average of heats of solution of single alkali glasses.
Heat of mixing for every composition was negative, and had a minimum at the mol ratio of large cation/small cation≥1. The heats of mixing were calculated by application of Lumsden model, which had successfully been applied to the calculation of the heats of mixing of two molten alkali halides with a common anion. The results show that the agreement of the calculated value with the observed one is fairly good for the glasses which contain relatively high amount of alkali cations.

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The free sintering of alumina (the sintering of free powder) was studied by measuring the surface area change with the BET method in the temperature range of 1035°C-1250°C. A kinetic equation describing the change of surface area was developed under the assumption that the neck growth and the surface flattening take place concurrently by the surface diffusion mechanism only. The analysis of the data with the kinetic equation showed that the surface area decreased first by the flattening and then by the neck growth. The surface diffusion coefficient obtained was given as D_s=2.83×10³ exp (-114.1/RT).

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The singl crystals of potassium hexa-titanate were synthesized by melt reacting TiO₂ and K₂CO₃, from which lattice parameters, indexes of X-ray powder diffraction data and infrared spectra were obtained.
The crystal system of potassium hexa-titanate was monoclinic. The space group was C*/* (C2, Cm, C2/m) and the cell dimensions were a=15.5878±0.0018Å, b=3.7979±0.0003Å, c=9.1131±0.0013Å, β=99.75±0.015°. This unit cell contained 2 (K₂Ti₆O₁₃)

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It was newly found that a larger amount of ZnO vaporizes from (Zn_0.5Co_0.5) O⋅1.3 Al₂O₃ than from (Zn_0.5Ni_0.5) O⋅1.3 Al₂O₃ when heated above 1300°C.
Cation vacancies tend to occupy B-sites in (Zn_0.5Co_0.5) O⋅1.3 Al₂O₃ and A-sites in (Zn_0.5Ni_0.5) O⋅1.3 Al₂O₃. The difference of vacancy distributions was considered to cause the vapor pressure differences.
Diffusional processes were also considered and it was assumed that Zn²⁺ diffuses outward by way of interstitial sites in (Zn_0.5Co_0.5) O⋅1.3 Al₂O₃, and that the driving force of the inward diffusion of Co²⁺ or Ni²⁺ is the difference of cation vacancy concentration between the surface and the inside of the pellet. The activation energies of interdiffusion of Zn²⁺ and Co²⁺, or Zn²⁺ and Ni²⁺ were 110kcal/mol and 78kcal/mol, respectively.

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