The reactions F¹⁹(d, p)F^20* and F¹⁹(d, p)²⁰ have been studied with deuteron bombarding energy of 1.3 Mev to 2.0 Mev. Angular distributions of protons leaving F²⁰ in 0.65 Mev excited state show a pronounced peak at about 60° over the entire deuteron energy range. On the other hand, those leaving F²⁰ in the ground state vary with the deuteron bombarding energy and most of them show no peak in the forward direction and a large peak in the backward direction. The absolute yields of the reactions have been measured at θ_cm=54° and θ_cm=104° as functions of the bombarding energy. A marked difference in the energy dependence of the yields for the two reactions is noted. The yield for the reaction F¹⁹(d, p)F²⁰ at θ_cm=104° shows a broad maximum centered at about 1.70 Mev deuteron energy, on the other hand that from the F¹⁹(d, p)F^20* reaction at θ_cm=54° shows a slow increase with increasing deuteron energy. These results at our bombarding energies show that the reaction F¹⁹(d, p)F²⁰ seems to proceed mostly by compound nucleus formation and the reaction F¹⁹(d, p)F^20* (0.65 Mev) seems to be caused by the stripping process of d neutrons.

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The absolute differential cross sections for the elastic scattering and the inelastic scattering (proceeding to the 1st excited state) of 14.1 Mev protons have been measured for Ni, Fe, Cr and Ti with a five-degree (or less) interval ranging from 20 to 165 degrees. The scattered protons were detected by NaI (Tl) scintillation counter whose energy resolution was about 2.3%. Even at small angles the protons inelastically scattered could be discriminated from those elastically scattered. The angular distributions of inelastic protons agree to that expressed by |j₂(qR)|² which one would expect from the theoretical prediction based upon the Born approximation.

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Thermodynamics of irreversible processes is applied to dense plasmas in a weak magnetic field. Basic equations of “magneto-thermo-hydrodynamics” are derived together with relations between transport coefficients. Extremely dilute plasmas and plasmas at the Debye-Hückel limit are discussed as particular eases.

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The measurement of Hall effect in oxide cathodes has been carried out in various methods of preparing samples.
The apparent electron mobility in a temperature range, 700°K∼1200°K, was about 10³∼10⁴cm²/v. sec.
These values are very high as compared with that for a single crystal. The effect of porosity upon the mobility seems to exist to some extent, the porosity being changed by means of the different preparations and treatments of the cathodes.
From the viewpoint of pore conduction the mean free path of an electron is about 10⁻⁶∼10⁻³cm which seems to be of the same order with the size of pores existing in the actual oxide cathodes.

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A detailed study has been undertaken on the transformation of nickel lattices under the influence of nitrogen as an “insertion” impurity. For this study, thin polycrystalline and monocrystalline layers of evaporated nickel have been heated in an atmosphere of ammonia. This nitriding process has been followed kinetically by electron diffraction. Using these techniques, it has been shown that the “insertion” of nitrogen atoms takes place in successive steps. First, a considerable expansion of the initial f.c.c. lattice of nickel (from a=3,52 to a=3,72 Å) is observed with the formation of Ni₄N. Then, if the nitriding is continued, this f.c.c. lattice of expanded nickel (Ni₄N) is transformed into a hexagonal lattice of Ni₃N.
The exact structure of these nitrides has been determined and a mechanism of the transformation from the expanded cubic nickel lattice (Ni₄N) to the hexagonal nickel lattice (Ni₃N) has been proposed. This mechanism consists, in part, of a series of microslips on the (111) plane and in the [11\bar2] direction of nickel atoms, similar to those produced in the martensitic transformation of cobalt, which transforms the stacking order of the {111} planes of the f.c.c. lattice into the stacking order of the {0001} planes of the hexagonal lattice. In addition, the diffusion of nitrogen results in another stacking transformation from the cubic {1\bar10} planes into the {1\bar210} planes of the hexagonal variety.

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Linear thermal expansion of CuAu single crystals was measured. When a bar-formed specimen was slowly cooled from above the transition temperature under compressive stress along its longitudinal direction, it was confirmed that the c-axes of the ordered phase were predominantly lined up in one of the cubic axes nearest to the stress direction. Furthermore a linear relationship was established to hold between the compressive stress previously applied and the amount of the dilatometric change due to the order-disorder transition. However, even when some of the crystals were initially annealed free from external stress, the tetragonal c-axes were not distributed statistically along the three original cubic axes.

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Artificial layers of selenides of Cd, Sn, Bi and Pb are made between the bulk Se and the counter electrode of selenium rectifiers with the method of vacuum evaporation. The d.c. and a.c. characteristics of these rectifiers are observed in order to get some informations about the actions of the barrier layer in usual selenium rectifiers. The results suggest that the roles of SnSe layer should never be neglected in the rectifying action in selenium rectifiers as well as those of CdSe layer, and the selenides of Bi and Pb seem to be undesirable materials.

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Structural studies on (Ba-Pb)(Ti-Zr)O₃ system were performed, and the phase diagram of the whole system was determined. In the vicinity of BaTiO₃, low temperature phases are brought to room temperature by adding Pb and Zr. Substituting some amount of Pb by Ba in Pb(Ti-Zr)O₃, Curie point becomes lower, but the morphotropic boundary between F_α and F_β Phase shifts only gradually to the Ti side, and may lie nearly at the same composition with varying temperature. The axial ratio in F_β phase decreases with decreasing Ti concentration, while 90°–a in F_α decreases with increasing Ba and hardly depends on Ti-Zr ratio.
Some solid solution ceramics along the morphotropic bundary with Ba 5–20% and Ti 40–50% are excellent for piezoelectric materials, and those containing Ba ca. 30% and Ti 5–25% have large dielectric constants and low temperature coefficients.

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The electronic structure of the M center for LiF has been investigated by L.C.A.O. approximation, assuming L-shape model by Seitz. In this treatment, we have orthogonalized the wave function of the M electron to the core state of Li ion, and evaluated the three center integrals more accurately than the former paper. The calculated value for the M band absorption is 0.078 compared with the experimental value 0.103 in atomic unit. Some discussions concerning to the approximation and symmetry problem are given.

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We invented the oxide-cored cathode. It is a fine platinum wire having an oxide-core. A thin platinum rod is bored along the axis, the empty core made by boring is filled with oxide powder and then the rod is drawn through a series of dies, forming a wire. For example, the diameter of the wire is 0.3 mm and that of the core 0.03 mm. The wire is cut into short pieces and when heated, the cross-section of the piece becomes an electron source.
The oxide-cored cathode was tested in conventional electron microscopes and was found to emit electrons from the cross-section of the core only and that generally, it is more durable than pure tungsten cathode.

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Thin iron films formed by evaporation were carburized in CO gas stream. The carbides ε, χ and θ were found to be formed in the temperature ranges (i) below 250°C, (ii) from 250° to 350°C and (iii) above 350°C, respectively. The ε-carbide is hexagonal with lattice constants a=4.767Å and c=4.354Å, and its structure belongs to the space group P6₃22, iron atoms occupying 6g positions with the parameter x=1⁄3 and carbon atoms 2d positions. Irreversible phase transitions from ε to χ and from χ to θ take place at 380°∼400°C and at about 550°C, respectively. By the transitions changes in the chemical compositions may be very small. Observation on the crystal growth suggests that a mechanism of the ε-carbide formation is different from that of the χ- and θ- carbide formations.

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Magnetic, thermal and crystallographic properties of sulfide as well as selenide of vanadium with nickel arsenide structure were investigated experimentally. The antiferromagnetic Néel points for these compounds were found to be about 1040° and 163°K respectively. A correction for the atom core diamagnetism was applied to the observed susceptibilities; the inverse susceptibility decreased linearly with the fall of temperature. Based on this result, the Curie constant, C_M, the spin quantum number, S and the asymptotic Curie temperature, θ, were obtained as 1.63, 2.9/2 −3000° for sulfide and 2.15, 3.2/2 and −2570° for selenide respectively. Anomalous heat absorptions at the magnetic transition in both compounds were 615 and 50 cal/mol respectively. Experimental results obtained are discussed briefly.

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The polarization characteristics of the sodium nitrate polarization prism are measured. Polarization effect is complete from 350 to 1,000 mμ; and transmission of light uncorrected for reflection at the surfaces is about 90% at above 400 mμ and 37% at 350 mμ. Possibility of making a polarization prism for a wide wavelength range from 250 to 1,000 mμ is discussed.

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The flow of a viscous fluid at low Reynolds numbers passing obliquely through a plane grid made of equal, parallel, circular cylinders regularly spaced is discussed on the basis of Oseen’s equations of motion. Explicit expressions for the force experienced by a cylinder in the grid, for the direction of the flow at infinity downstream, and for the pressure drop caused by the grid are obtained correct to the first order in the Reynolds number and in the diameter-distance ratio of the grid.
Among these the following results may be worth mentioning. The flow is deflected by the grid more or less to the direction of the normal to the grid surface and is always slowed down at infinity downstream. At very small Reynolds numbers, the flow becomes almost perpendicular to the grid even at far upstream and, hence, the component of force tangential to the grid surface vanishes, while the normal component of force to the grid surface becomes equal, in its magnitude, to the drag when the grid is set at right angles to the uniform stream whose velocity is equal to the normal component of the original velocity.

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Problems on heat conduction in multilayer bodies lead usually to complicated calculations. The present paper gives an idea of specific difficulties arising in the ease of infinite composite solides. General deductions are applied to a special class of questions.

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