Using 5.7 Mev protons from the cyclotron, the angular distributions of protons elastically scattered from Fe, Cr and Ti were investigated by means of nuclear emulsion technique. The angular distributions of the elastically scattered protons by these nuclei were similar to that of Ni, that is, the differential cross sections in the ratio to those of the Rutherford scattering increase linearly at large angles. Some qualitative arguments are given about this characteristic feature of these nuclei, together with previously measured elements Ni and Zn.

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By bombarding a natural calcium target with 5.7 MeV protons, gamma rays of energy 3.7 MeV and 3.9 MeV were observed with a NaI(Tl) three crystal pair spectrometer. The intensity of 3.7 MeV gamma ray is about 25% of 3.9 MeV gamma ray.
Angular distribution of these gamma rays was measured with a single crystal scintillation spectrometer. The result can be expressed as follows: 1+1.90cos²θ–1.03cos⁴θ.
From comparison with theory it is highly probable that 3.90 MeV state has spin 2.

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The angular distributions of protons inelastically scattered from Mg²⁴ (Q=−1.368 MeV) were measured from 22.5° to 165° in the laboratory system at incident proton energies of 5.1 and 5.4 MeV. The 44″ Osaka University cyclotron was used to provide a proton beam, and the scattered protons were detected by nuclear emlusion technique. Both distributions obtained show an asymmetry about the center of mass scattering angle θ=90° and a strong dependence with the energy of primary protons.

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The first excited state (122–keV) of the even-even nucleus Sm¹⁵² was excited by the Coulomb excitation with 2-MeV protons. The angular distribution of the de-excitation radiation was investigated. The attenuation factor of the angular distribution G₂∼0.6 was obtained using a samarium oxide target. The rotational change of the pattern in the angular distribution was examined under the condition of applying an external magnetic field vertical to the incident protons. The apparent g-factor for this state obtained was g(Sm¹⁵²,2⁺)=+(0.36±0.16) n.m. A brief discussion about the effect of nuclear surroundings affecting the present determination was given.

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A new optical device to study the resultant movement of many walls in rochelle salt was constructed. It was found that the rotating angle of the optical plane is nearly in proportion to the spontaneous polarization. Some characteristics of the resultant wall motion were studied from the information of the rotating angle. From these experimental results we are inclined to conclude that the fatigue effect will be caused by either the displacement of dislocations or neutral vacancies.

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By using a newly proposed model, in which the positive charges of bare nuclei of an impurity atom and the matrix atoms are put at the lattice points and all the electrons, valence electrons as well as core ones, are treated by Thomas-Fermi method, the deviation of the potential from the periodic one for the pure matrix metal due to the presence of an impurity atom has been calculated and compared with the screened Coulomb potential obtained in previous papers.
In the case of pure metals, a similar treatment was made by Slater and Krutter, so that our model may be regarded as an extension of theirs to the case of substitutional impurity.
Our obtained potential is nearly proportional to ΔZ, where ΔZ=Z_i–Z, Z_i and Z being atomic numbers of the impurity and the matrix atom respectively and in this paper, we have treated the cases of ΔZ=±2 and ±1.

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The energy band structure of the β- (zincblende-type) SiC crystal is worked by the orthogonalized plane wave (OPW) method. Since this crystal will be the typical one of the IV–IV compounds, the results of calculation for its electronic structure will be useful for systematic understanding of the transitions of the electron-behavior from the group-IV valence-crystals to the III–V compounds etc.. Our results show that the conduction band-minima occur at X-point or its immediate neighbor, while the valence band-maximum perhaps at Γ-point. Hence the indirect interband-transitions in the long wave limit will be expected to occur between these two states with the energy difference of 2.2 ev, and the direct interband-transitions at X-point will take place at a photon energy of 6.3 ev. Further the approximate charge-distribution in the crystal is worked by making use of the obtained Γ-valence eigenfunctions, which result seems to show that the electrons in its \veck=0 levels of the β-SiC will be approximately a covalent-like distribution as far as Γ-eigenfunctions do concern. Finally, an idea is proposed to improve the slow-convergence of the OPW method for conduction bands of insulators. Its practical application is now in progress for the β-SiC.

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A crystallographic study on the mechanical twinning in Ti and α-U is made by a method similar to that in a previous paper, allowing more kinds of atom movements, and the twin elements, K₁, K₂, η₁ and η₂, are determined. It is found that {11\bar22} and {11\bar24} twins in Ti are reciprocal to each other and that the elements of {11\bar21} twin are in agreement with Hall’s result. It is also found that a general result that a plane having the smallest shear S is liable to twin in order nearly holds in Ti and α-U.

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Below the transition point 109°K a crystal plate of NaNH₄-tartrate shows a domain structure under a polarizing microscope if viewed in the direction parallel to the b axis. The polarization in each domain lies parallel to +b or −b axis, and can be reversed by shearing stress. The spontaneous polarization is 0.21μ Coul/cm² at 92°K and it is probably constant below the transition temperature.

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The perturbation theory of the temperature diffuse scattering of electrons is presented taking account of the fact that each of the primary and secondary waves in the crystal consists of many plane waves. Formulae for the intensity of the diffuse scattering from a monatomic crystal forming a primitive lattice are obtained for each of the perturbation potentials due to Bloch and to Nordheim. When each of the primary and secondary waves does not excite any Bragg reflexions and can be given by a plane wave, the Nordheim potential gives the same result and the Bloch potential gives practically the same result as that of the current X-ray diffraction theory applied to electron diffraction. The result may be applied to explain the formation of the Kikuchi pattern by the temperature diffuse scattering and the anomalous intensity variation of the diffuse spot from some single crystals.

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The results of the perturbation theory of the temperature diffuse scattering of electrons developed in the preceding paper are applied to practical problems with the assumption of two plane waves.
It is shown that the intensity of the diffuse scattering does not become infinite at a reciprocal lattice point as it does in the current theory but remains finite, that the temperature diffuse scattering gives rise to Kikuchi patterns, and that the intensity of diffuse spots changes abruptly when the incident wave excites a Bragg reflexion. The anomalous intensity variation of the diffuse spots from the surface of some single crystals may be due to this effect. In the Bragg case the direction of the diffuse scattering can be obtained by the modified Ewald construction which replaces the Ewald sphere by the equi-energy surface in the reciprocal space.
The possibility of treating the Kikuchi pattern due to the inelastical collision of incident electrons with lattice electrons by the present method is also discussed.

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The electrical and optical properties of the transparent conducting tin oxide films were studied experimentally. The observed Hall effect and Seebeck effect show that the present specimens are n-type conductor whose carrier density is 10¹⁹∼10²⁰ cm⁻³. The optical measurements made it clear that the fundamental energy gap was about 4 ev and the plasma frequency of the conducting carriers lied in the near infrared region. By comparing the observed optical transmission and reflection with the theoretical values which can be calculated with the electrically measured constants, the effective mass of the carriers was determined to be about 1/5 of the free electron mass. It will be discussed in conclusion that, to satisfy the thermoelectric power relation with this small effective mass, we must assume that the Coulomb scattering of impurity ions is the predominant scattering mechanism in the transparent conducting tin oxide films.

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A large number of creep rupture tests on OFHC copper wire have been carried out at stress levels of 24.0∼25.0 Kg/mm² and temperatures of 8∼40°C. The F-test was made for the differences in variance between time for initiation of accelerating creep and time for rupture measured from the initiation of accelerating creep, and the regression analysis between these times was carried out. The scatter observed for these times appears to be an inherent characteristic of the material itself associated with a Markoff process—dynamic statistical process— as a rate process.

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