A model is developed to explain the dependence of the diffusion coefficient of an interstitial solute upon the concentration of substitutional solute. In the model, substitutional solute atoms act as traps for diffusing interstitial atoms and thus decrease the number of atomic jumps through the lattice of the solvent, but diffusion can also take place by jumps out of traps and within overlapping traps. Two parameters are used to develop the theory: the size of the trap around a substitutional atom, and the interstitial-substitutional solute binding energy. Three terms are shown to contribute to the magnitude of the interstitial diffusivity. The first term is for atomic jumps in the host lattice and from lattice into traps. The second is for jumps from traps to host lattice. The third is for jumps which occur entirely within traps. The theory predicts a marked initial decrease of the interstitial diffusion coefficient as a function of the substitutional concentration. After this initial decrease, the diffusivity goes through a minimum, and the position of this minimum depends upon the trap radius.

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Silver and copper were vacuum-deposited onto an electro-polished aluminium substrate cooled by running water to a thickness of about 2 μm, and the films were investigated by means of transmission electron microscopy, electrical resistivity measurement, differential thermal analysis and X-ray diffraction. The results obtained are as follows.
In as-deposited silver films, the {111} preferential orientation was observed, but it disappeared after recrystallization. Continuous heating caused rapid recrystallization in the temperature range from 30 to 50°C accompanied by the change in resistivity and the heat evolution. The activation energy for recrystallization was estimated at 84 kJ/mol.
For copper, the recrystallization gave rise to such a complete reorientation that the {100} plane was parallel to the substrate.
The contribution of the strain energy to the heat released during recrystallization was negligibly small. The grain boundary energies for silver and copper were estimated from the heat evolution to be approximately 3.2×10⁻¹ and 8.1×10⁻¹ J/m², respectively.

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It is well known that the viscosity of the molten FeO–SiO₂ system exhibits a marked hump near the fayalite composition. In order to ascertain this phenomenon, the viscosity and density of the molten FeO–SiO₂ system were measured with special emphasis on the behavior of the fayalite melt. The viscosity measurement was carried out by a rotating cylinder method and the density measurement was made by an Archimedian method using two bobs. The experimental results revealed small but sharp humps on both of the viscosity and expansivity vs the composition curves near the fayalite composition.
The origin of these phenomena may be attributed to the presence of the fayalite cluster in the melt. Then, the amount and size of such cluster are estimated by the applications of Einstein’s equation derived for a viscosity of a colloidal solution and some thermodynamical relations. The calculated results show that the amount of the cluster having a size of (Fe₂SiO₄)_11∼12 is about 15% in volume at the melting point, decreases with increasing temperature, and vanishes at temperatures between 1800–2000°C. It is discussed also that the feature of the molar volume of fayalite melt can be explained by the same cluster model derived from the viscosity data.

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The e.m.f. measurements were carried out in the temperature range of 1173∼1323 K by means of the following galvanic cells employing solid electrolytes:
Ni.NiO(s)/ZrO₂+CaO/Pb.PbO−SiO₂−MeO(1)
where MeO is CaO, Al₂O₃, MgO and ZnO.
From these experimental results, it was found that the activity of PbO in the molten PbO–SiO₂ system was increased remarkably by the addition of CaO or MgO, considerably by ZnO and slightly by Al₂O₃.
These experimental results were found to be in good agreement with the results of Richardson and Pillay on the PbO–SiO₂–CaO, PbO–SiO₂–MgO and PbO–SiO₂–ZnO systems.

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Irreversible lattice defects left behind in the parent phase after a complete transformation cycle (parent-martensite-parent) in nearly thermoelastic specimens were studied by transmission electron microscopy. A commonly observed configuration is that of parallel dislocations lying on the (101)_f plane and along the [\bar101]_f direction, forming pairs with other dislocations which lie on adjacent (101)_f planes some 5 to 10 nm apart. Another structure observed is what is supposed to be the junction plane of pairs of martensite variants once exising at a low temperature. The junction plane of a pair of variants which formed a wedge morphology contains two directions of line defects (probably dislocations), each of which corresponds to the intersections of the transformation twin planes of each vaiant and the junction plane. The junction plane of a pair of variants which formed a spear type morphology shows a single direction of line defects, and the junction region of a pair of variants which formed a kink type morphology contains a cluster of dislocations.

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The anodic extraction of vanadium from crude vanadium (93.4–97.3 wt%) produced by carbothermic reduction was studied in the temperature range of 700–850°C, in the cell voltage range of 0.2–1.0 V, and in the four kinds of electrolytes KCl–NaCl–VF₃(47.5–47.5–5), KCl–NaCl–K₂NaVF₆ (47.5–47.5–5), KCl–NaCl–NaF–K₂NaVF₆(44–44–7–5), and KF–NaF–K₂NaVF₆(62–33–5). The highest anode current efficiency was obtained under the conditions of 0.8–1.0 V and 700–725°C in the KCl–NaCl–NaF–K₂NaVF₆ electrolyte. The anode current efficiency was found to be strongly dependent on the vanadium content of the crude vanadium. It was also found that the oxygen and carbon in the crude vanadium remain in the anode residue as VO, V₂O₃, VC, and free carbon.

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