Gamma ray spectrum from silicon bombarded by 5.7 MeV protons has been studied by a scintillation spectrometer. The following gamma rays due to inelastic scattering of protons were observed. 1.78 MeV (²⁸Si 1st—ground), 1.28 MeV (²⁹Si 1st—ground), 2.03 MeV (²⁹Si 2nd—ground), 2.43 MeV (²⁹Si 3rd—ground), 2.24 MeV (³⁰Si 1st—ground). Excitation curves for the 1.78 MeV gamma rays have been measured in the proton energy range from 2.2 to 5.7 MeV. Resonances were found at 2.9, 3.5, 4.4, 5.0 and 5.4 MeV. At 5.4 MeV, the angular distribution of the 1.78 MeV gamma rays was measured. By comparison with theory, the corresponding compound level of ²⁹P at 7.9 MeV was assigned d_5⁄2.
The cross section for this process is 250 mb.

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A magnetic spectrometer with inclined plane pole-faces has been constructed for the velocity analysis of low-energy electrons. The magnetic field strength H at a point P satisfies
H=H₁⁄r,
where H₁ is a constant and r is the distance from the line of intersection of the two pole-planes to P. The momentum dispersion of our spectrometer is about 3 times larger and the solid angle of the collection is more than 10 times wider than those of a conventional semi-circular spectrometer of similar dimensions. The equation which determines the momentum dispersion was obtained and the conditions for focusing were discussed.

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The behavior of ferromagnetic precipitates in copper-cobalt alloy containing ca. 2 wt. % cobalt heat-treated with magnetic field was studied with the object of making clear a physical origin of the induced uniaxial anisotropy observed. The magnitude of magnetic anisotropy induced by magnetic annealing was measured as functions of the aging temperature, aging time, and intensity of magnetic field. It has been found that almost all of the experimental results can be explained by the fine-particle behavior of ferromagnetic precipitates. It is shown that the origin of magnetic annealing can be explained neither by the magneto-elastic anisotropy of directional deformation nor by the magnetocrystalline anisotropy, but by the shape anisotropy of precipitated particles, which is distributed preferentially along the direction of magnetic field applied during annealing. It is also shown that the magnetic annealing affects remarkably the initial precipitation process rather than the over-growth stage of precipitation.

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High purity germanium monosulfide was prepared and its semiconducting properties were measured. Samples are obtained by the reaction of germanium and sulfur in vacuum at high temperature and reducing in ammonium gas to remove germanium disulfide. Dark resistivities of evaporated layers and polycrystalline blocks of GeS prepared by the above method are 10¹⁰Ω cm or more.
1. The thermal activation energy for dark current is 0.74·1.0 ev and about 0.25∼0.5 ev at higher and lower temperature regions, respectively.
2. The absorption edge is found at about 700 mμ from the optical measurements.
3. At room temperature the maximum spectral sensitivity of photo-conductivity is observed at the wavelength of about 700 mμ in vacuum and of about 800 mμ in room air.
4. The sign of the observed thermoelectric power is that of p type at high temperature, and its magnitude is about 1 mv/deg.

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We studied the electronic energy bands of graphite by the Bloch method and then calculated the diamagnetic susceptibility. The calculated value of the main term in Peierls’ constant susceptibility (parallel component to c-axis) is about 0.3 times the experimental value, and the theoretical value of periods (on the basis of Onsager’s theory) of two types with regard to the de Haas-van Alphen effect is about 2.5 times the experimental value. The cause of such discrepancy is discussed.

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The paramagnetic resonance due to a Z₁-center electrons in potassium chloride is investigated. Since Z₁-centers are always accompanied by F-centers, the contribution from F-centers ought to be substracted from the resultant curve in order to get the absorption curve due to Z₁-center alone, which is found to be Gaussian with the half width of 79 oersteds and g value of 1.999. The result is annalyzed according to the model that an electron is trapped by a divalent cation substituted for a cation of the bulk crystal.

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The magnetic anisotropy of NiO single crystal grown by the Verneuil method was measured using a torque balance. An X-ray study showed that the crystal, despite its outward appearance of a single crystal, is composed of small rhombohedral domains twinned through {100} planes. By applying a pressure along one of the [111] axes of the crystal during annealing from above the Néel temperature, the twin structure was partly removed. Torque measurements in a homogeneous magnetic field and their analysis showed that in pressure-annealed crystals domains with trigonal axis pointing along the direction of the pressure dominate but antiferromagnetic domains in each crystallite are distributed at random. The spin axis was found to be in the plane parpendicular to the trigonal axis within ±16°.

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The fine structures of X-ray K absorption spectra of nickel in metallic nickel, NiO, Ni₂O₃ and NiO₂·nH₂O were photographed by a bent crystal spectrograph. The fine structures of absorption spectra of metallic nickel and NiO agree well with those published by previous authors, but those of Ni₂O₃ do not coincide with those reported by Hayasi and Cauchois. Also Cauchois’ data of Ni₂O₃ do not coincide with Hayasi’s data. This seems to be due to doubtful chemical structures of Ni₂O₃ and it is supposed that the three specimens used by the three authors might have different chemical structures. The first absorption maxima A are much more pronounced with increasing oxygen proportion and the general features of α, β, C and γ of the absorption spectra of oxides are similar respectively. However, the second small absorption maxima B are less pronounced with increasing oxygen proportion. These facts are expected from Coster and Kiestra’s and Cauchois’ considerations. It may be considered from the comparison of the present curves of absorption spectra only that nickel sesquioxide is a mixture of NiO and NiO₂·nH₂O.

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The fine structures of X-ray absorption by single crystals of germanium were investigated. These crystals were used as an analysing crystal of a spectrometer and at the same time as an absorber. The intensities of general radiation reflected from (1 0 0), (1 1 0) and (1 1 1) planes were investigated. The fine structures of intensities reflected from these planes were in agreement with those of absorption spectrum reported by Doran and Stephenson obtained by the transmission method using a single crystal as an absorber. However, they reported that they observed a weak fine structure near the absorption edge which was not observed by us. The observed fine structure of the absorption can be interpreted in terms of Kronig’s theory, while the absence of the fine structure near the absorption edge is due to the anomalous scattering of germaninum on the one hand and to the thickness effect reported by Parratt, Hempstead and Jossem on the other.

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The spin-lattice relaxation time, T₁ and the spin-spin relaxation time, T₂, of the resonance line in metal cadmium were measured by use of a nuclear magnetic resonance technique. The contribution of p-character in the conduction electron to the relaxation was estimated. The line width was measured at a temperature between the room temperature and 250°C. It was shown that the exchange broadening between unlike spins underwent a motional narrowing. The inverse line width or spin-spin relaxation time, T₂, was interpreted in terms of the lattice diffusion theory. These analyses yielded for the coefficient of self-diffusion D the value 0.05 cm²/sec exp (−17.6 kcal/mol-RT).

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Polyethylene films were irradiated in the air by deuterons accelerated by a cyclotron and by gamma rays from cobalt-60 source. Gel fraction, swelling ratio, weight changes and infrared absorption spectra of irradiated specimens were measured. It was found that the specimen irradiated by deuterons was cross-linked and became insoluble in xylene. The effects of deuteron irradiation seem almost the same as those of other ionizing radiations such as pile or gamma rays. Infrared absorption spectra reveals some difference in that the ratio of E_co⁄E_cc is 0.65 in the deuteron irradiation and is smaller than the value of 14.0 resulting from gamma ray irradiation, where E_co is the optical density of carbonyl groups and E_cc that of unsaturation. Some considerations are given on the possible explanation of this difference.

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Polyvinyl alcohol in the form of film and powder were irradiated in the air by gamma rays from cobalt-60 source, and by deuterons accelerated by a cyclotron. Weight changes, viscosity, solubility and infrared absorption spectra of irradiated samples were measured as a function of absorbed dose. The reduction of the molecular weight of the irradiated specimens was observed suggesting that the effect was one of degradation. Infrared absorption spectra showed the formation of the carbonyl groups in the irradiated specimen.

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The physical Properties of polyvinyl alcohol irradiated by deuterons or gamma rays were found to change remarkably by heat treatment. Irradiation causes the decrease of the molecular weight and the increase of the carbonyl groups. When these specimens are heated above 120°C, however, the solubility diminishes considerably and even gel formation occurs for highly irradiated ones. Infrared absorption spectra revealed that the number of carbonyl groups formed by the irradiation decreased greatly as a result of heat treatment. Some discussion are given on the process of gel formation.

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Nuclear quadrupole resonances of I, Br, Cl, As and Sb isotopes in solids AsCl₃, SbCl₃, SbBr₃, AsI₃, SbI₃, AsI₃·3S₈, SbI₃·3S₈, SnI₄, SnI₄·2S₈ and SnI₄·4S₈ have been measured systematically. The newly obtained coupling constants eQq and asymmetry parameters η of the I¹²⁷ resonances at 77°K are as follows: eQq=1383.03, 1402.68 Mc: η=0.002, 0.039 in SnI₄·2S₈, eQq=1364.3, 1368.3, 1405.0 Mc and η=0.00, 0.00, 0.03 in SnI₄·4S₈. In SnI₄·4S₈ an additional line was observed at 219.04 Mc corresponding to the first resonance. The second resonance of SbI₃ was at 254.637 Mc with eQq=895.83 Mc and η=0.565. Resonance frequencies of As⁷⁵ in AsI₃ and AsI₃·3S₈ at 77°K were 29.338 and 49.501 Mc, respectively. The first resonance of Sb¹²¹ in SbI₃ was 25.406 Mc at 77°K and the corresponding resonance in SbI₃·3S₈ was 37.461 Mc at 297°K. SbBr₃ showed two crystal forms which gave Sb¹²¹ coupling constants of 319.920 and 316.02 Mc and asymmetry parameters of 0.082 and 0.182 at 304°K, respectively. On the Br resonances of SbBr₃ three resonance lines instead of two hitherto reported were observed in both crystal forms.
Coupling constants of trihalides were compared with their chemical bond properties. The constants of AsI₃ and SbI₃ are different from those of other compounds, while their sulphur moleculor addition compounds are in rather good agreement.
AsI₃ showed positive temperature dependency for arsenic isotope as for the case of iodine isotope.

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A torsion pendulum magnetometer whose sensitivity is 1×10⁻¹⁰ c.g.s.e.m.u./division was made with fused silica. By using this, a process in which the free radicals appear and disappear was traced magnetically from time to time during the reduction of duroquinone with glucose, and the result showing a fair agreement with Michaelis’ was obtained. Secondly, we examined similar reactions by changing reducing agents, their concentrations and the temperature. Finally, the mean life time of free radicals was calculated from the observation. Then it was found to be shown as an exponentially decreasing function with temperature, and to be about 20 minutes at room temperature.

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The slow steady flow of a viscous incompressible fluid past a thin screen with holes or slits is investigated on the basis of the Stokes equations of motion. It is found that the flow conductance σ of the holes or slits (i.e. the ratio of the total flow Q to the pressure drop P) is given by
σ=\fracQP=\fracM8ρμ,
where ρ is the density of the fluid, μ the viscosity, and M the virtual mass of disks or strips which are congruent with the holes or slits, moving broadside-on in a perfect fluid. The drag D acting on a part of the wall δW of the screen is also given by
D=Pq_p,
where q_p is the total flow of the perfect fluid through δW in this movement with unit velocity.
As examples, the cases of a single elliptic hole, a single slit, two parallel equal slits, and a series of parallel equal and equidistant slits are considered. Especially, in the last case, the total drag for an intervening strip is shown to be 4πμU⁄log|cos(επ⁄2)| where U is the velocity of the viscous fluid at infinity, and ε the relative aperture of the screen (0<ε<1).

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An asymptotic calculation of the response function of an optical system which has the primary spherical aberration is carried out in the presense of a defect of focus. The evaluation of the integral for the response function is calculated by the aid of the approximate formulae for Fresnel’s integral when the coefficient of the spherical aberration is sufficiently large compared with the wave length of light. The response function denotes an interesting behaviour for various focal shifts even for a fixed value of the coefficient of the spherical aberration. When the shift is small, it has a strong decreasing character, and for larger values of it, the function becomes larger and begins to denote an oscillating property at last. The spatial frequency s extends from zero to 2 and the result is not valid in the neighbourhoods of the end points because of the simplification of the calculation which is used. The result is compared with an experiment.

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The adsorption of water vapour on lead borosilicate glass, soda lime glass, copper, nickel and alumina ceramic in high vacuum was studied by the time lag method of molecular flow originated by Barrer. The amount of adsorption at 273°∼403°K and 2×10⁻⁵ mmHg was found to be less than 1 % of a monolayer. It is suggested that the adsorption of water vapour in this pressure region will not be a simple physical adsorption.

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