The angular distribution of α-particles from the reaction ¹⁹F(pα)¹⁶O^*(π)¹⁶O has been measured at fourteen energies between 800 kev and 1400 kev. The α -particles were detected and identified by coincidence with nuclear pair-electrons. The data were analyzed to give coefficients in the expansion formula σ(θ)=a₀+a₁cosθ+a₂cos²θ+a₃cos³θ+a₄cos⁴θ. The spins of the levels of the compound nucleus ²⁰Ne were assigned from the evidence of anomalies in the coefficients. For the resonances at 843−, 1126−, 1355−kev J=2 and for that at 1250 kev J=1.

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Ordering processes in the CuAu alloy were studied by X-rays using single crystals. Characteristic diffuse scattering effects, which may be regarded as similar phenomena to those in the partially ordered CoPt alloy, were observed at early stages of the ordering. The change in X-ray diffraction pattern during aging was discussed on the basis of kinetics of the ordering reaction.

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The conductivity, the Hall coefficient and the thermoelectric power of the compound Bi₂Te₃ have been measured over the temperature range from 100°K to 750°K. The specimens used show electrical conduction of p-type at room temperature and the hole mobility temperature dependence is represented by the relation μ_h=1.2×10⁸T^−2.3. It is found that the forbidden energy gap E_G is 0.21 eV at 0°K, and the effective masses of holes and electrons are, respectively, 1.26 m and 1.07 m, and the mobility ratio b is about 1.7.

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Kasteleijn’s method of obtaining the ground state of antiferromagnetism is generalized to the cases of two and three dimensional lattices. According to our generalization, the ground state of the three dimensional antiferromagnetic Heisenberg model with the spin quantum number equal to one half is paramagnetic in the absence of anisotropy energy. The magnetization of sublattices is calculated as a function of the degree of anisotropy. With increasing coordination numbers the anisotropy energy necessary for establishing the antiferromagnetic state decreases rapidly.

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The first stage of the sintering process between barium titanate and strontium titanate powders, which are responsible for the formation of solid solution, was investigated. We measured the variation of permittivity vs. temperature characteristics and crystal structure of the mixtures, with sintering conditions. The shift of the effective Curie temperature and the broadening of diffracted lines were observed in the transient states of the reaction. A diffusion mechanism was introduced in order to interpret these phenomena qualitatively.

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The ordered arrangements of the defects of iron atoms in FeSe_x have been studied for several compositions by X-ray analysis. These defects tend to assume an ordered arrangement as in the case of pyrrhotite FeS_1.14. New phases are found in the region (x=8⁄7∼4⁄3) which have been considered as the single phase region. If we choose the orthohexagonal and pseudo-orthohexagonal unit cells for x=8⁄7 and 4/3, respectively, the unit cell dimensions of the superstructure resulting from this ordering are twice as large as that of the fundamental structure along the a- and b-axes, and three times along the c-axis for x=8⁄7, and on the other hand, twice only along the c-axis for x=4⁄3.

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A new simple but fairly accurate method for the determination of elastic constants of cubic crystals from the observation of the temperature diffuse scattering of x-rays has been developed. The elastic constants of silver, copper-zinc and silver-copper alloys were determined by this method. Diffuse scattering due to the disorder of atoms as well as due to the thermal motion of atoms were considered in the case of alloys. In silver-copper alloy, the abnormal diffuse scattering, probably due to the former cause, was found along the [001] direction from the (004) reciprocal lattice point. The elastic constants obtained were as follows:
(Remark: Graphics omitted.)

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The temperature dependence of anisotropy energy of ferromagnetics was calculated by the spin wave method which assumes the existence of only pseudodipole interaction which included some restricted long range forces. The temperature dependence obtained is (M⁄M₀)¹⁶, a result which is in fairly satisfactory agreement with the experimental (M⁄M₀)²⁰ law, and is an improvement on Van Vleck’s result (M⁄M₀)³. This small discrepancy is discussed from the standpoint of s-d interaction.

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The paramagnetic resonance spectra of some ammine, ethylenediammine, and pyridine derivatives of hydrated cupric salts were examined, using their single crystals and microwaves of λ=32∼5 mm. In the cases of [Cu(NH₃)₄] SO₄·H₂O and [Cu(en)₂] Cl₂·xH₂O, detailed analysis of spectra was performed using the structural data from x-ray analysis given by Mazzi. In the other cases, analysis was discussed under an assumption of inequivalent magnetic units. Results thus obtained are fully explained by the treatments given by Abragam and Pryce with modified λ, the spin-orbit coupling coefficient, so the forces acting between the central copper ion and the surrounding nitrogen atmos are supposed to be mainly ionic rather than covalent, as in the cases of usual hydrates. Exchange energies between copper ions are also discussed.

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Zeeman patterns of the nuclear Quadrupole resonance line of I¹²⁷ were studied with a single crystal of iodine at medium and weak magnetic fields. The asymmetry parameter of coupling, η, and the angle between bond axis of the iodine molecule and crystallographic c axis, \varphi, were determined from the pattern at a medium magnetic field of about 120 gauss. The result was η=−0.16±0.01 at 14°C when crystallographic b axis was chosen as x axis and \varphi=31°38′±60′. The absolute value of η is in accord with the value obtained by the two resonance frequencies, i.e. 0.151±0.001 at 11°C, \varphi agrees with that obtained by the X-ray diffraction, 32°4′. At a weak magnetic field, Zeeman patterns of the fine structure of iodine were examined at three directions of magnetic field against the iodine crystal, i. e. the b axis, the c axis and the direction of 60° from the b axis in the bc plane. Behaviour of the superregenerative detector used for these N.Q.R. measurements was studied and the observed shape of the resonance line is discussed.

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The complex structure of the line which was found in the nuclear quadrupole resonance in solid iodine was studied with recording instruments. The recorded pattern of the low-frequency line spreaded in the range of about 80 kc and resolved into five lines at least. The pattern changed considerably when the radiofrequency field was orientated with respect to the crystallographic axes. The structure was explained to be caused by the electron-coupled spin-spin interaction.

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The anomaly of the rotational intensity distribution of the OH band excited by vacuum discharge is explained as due to the existence of two unstable excited states of H₂O molecules, through which a radical OH in the excited states (²Σ) is produced. It is shown that the intensity distribution of the band excited by electrons with known energies depends upon the energy of impinging electrons in the electron impact experiments. The feature of the distribution of the band intensities from molecules excited by usual electric discharge can be understood as to be determined by the energy distribution of electrons in discharge tubes.

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Transmittance and reflectance of magnesium fluoride films deposited on optical glass and fused quartz are measured as functions of wavelength between 3500Å and 6000Å. Film deposited on fused quartz kept above 240°C shows remarkable scattering as compared with that of film deposited on optical glass under the same condition. This difference is explained by the affinity of film to substrate surface. Index of refraction is determined from wavelength of refraction of determined from wavelength of transmittance extremes and film-thickness. The aging effect can not be observed. The causes of porosity of films are discussed.

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A general formula for the expansion coefficient of one atomic orbital in spherical harmonics around another center, which is useful in numerical evaluation of molecular integrals, is derived and applied to the evaluation of certain two center integrals.

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As a continuation of the previous study on the impulsive motion of an advancing wedge (J. Phys. Soc. Japan 10, 221 (1955)), we now consider the case in which the wedge is receding. The general features of both cases are similar. We now have rarefaction waves instead of the shock waves which played a fundamental role in the previous paper. The two limiting cases of small, and almost blunt, vertex angles are discussed analytically. The former is essentially the same as the corresponding case of the advancing wedge. On the other hand, the latter presents new features.

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We investigate the problem of a thermally conducting solid, initially at a uniform temperature, part of whose surface is insulated. The uninsulated part of the surface radiates heat into a medium at zero temperature. We deal especially with the case in which the insulated and uninsulated regions cannot be represented as distinct coordinate surfaces in variables in terms of which the conduction equation is separable.
An integral equation is derived for the boundary values of the temperature and solutions of this equation are obtained in two special cases, viz. a semi-infinite solid insulated except for a single infinite strip, and the same solid insulated except for two equal parallel infinite strips at a considerable distance apart. In both cases we show that the solution can be represented for large values of the time t, by a series of inverse powers of logt. In case the strips are very narrow we obtain closed expression which approximate the sums of the series.

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The steady slow motion of a circular cylinder in a semi-infinite viscous liquide bounded by a plane wall is discussed on the basis of Stokes’ equations of motion, assuming that the cylinder is moving parallel to the bounding wall. It is shown that the components of velocity satisfying the boundary conditions on the bounding plane wall as well as at the surface of the cylinder, satisfy also automatically the conditions at infinity. A second approximation for the drag on the circular cylinder is obtained. As far as higher order terms are neglected, it is in perfect agreement with the first approximation obtained recently by the present writer on the basis of Oseen’s linearized equations of motion.

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The steady slow motion of a circular cylinder in a viscous liquid bounded by two parallel plane walls is discussed on the basis of Stokes’ equations of motion, confining ourselves to the case when the cylinder is moving midway between the bounding walls. A second approximation for the drag experienced by the cylinder is then calculated and compared with White’s experiments. But the disagreement existing between the first approximation obtained recently by the present writer on the basis of Oseen’s linearized equations of motion and White’s empirical formula, when the values of the ratio (distance between the walls/diameter of the cylinder) are smaller than 20, has hardly been removed. As far as higher order terms are neglected, the second approximation is in perfect agreement with the first approximation.

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