The gamma-rays following the inelastic scattering of protons by ²⁴Mg, ²⁵Mg and ²⁶Mg were investigated at proton energies up to 5.7 MeV.
The energy spectra of the gamma-rays at several proton energies have been obtained for each isotopes.
2⁺ was assigned to the second, third and fourth excited level of ²⁶Mg considering the gamma-ray branching ratios for those levels.
The yields of gamma-rays from the first excited levels were found to have peaks at proton energies of 4.0, 4.6 and 5.05 MeV for ²⁴Mg(p, p′γ) reaction, 4.9 and 5.4 MeV for ²⁵Mg(p, p′γ) reaction respectively. These resonances correspond to the levels at 6.1, 6.7 and 7.14 MeV for ²⁵Al, and 13.0 and 13.5 MeV for ²⁷Al.
To determine the spins for those levels, angular distributions were measured at resonance energies. Spin values of 3/2 and 5/2 are probable for 7.14 MeV level in ²⁵Al and 13.0 MeV level in ²⁷Al respectively.
For the 13.5 MeV level in ²⁷Al, the spin of 3/2 is also probable, but 5/2 can not be excluded because of the presence of the cascade gamma-rays from higher levels.
The total cross sections for the gamma-ray emission are estimated to be about 700 mb at 5.05 MeV resonance for ²⁴Mg and a few hundreds mb for the 4.9 and 5.4 MeV resonances for ²⁶Mg.

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The convex-core model of nonspherical molecules, introduced for the sake of treating the second virial coefficients of nonpolar gases (T. Kihara: Revs. Modern Phys. 25 (1953) 831), is applied to crystals of methane, carbon dioxide, and nitrogen. By use of model parameters determined from the second virial coefficients, lattice constants and cohesive energies are calculated. For methane, results of the calculations agree with observed values when the zero-point energy and the effect of potential non-additivity are taken into account. The crystal structure, the lattice constant and the cohesive energy of carbon dioxide are explained by use of a convex-core model with an embedded electric quadrupole.

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The quantum efficiency for the bleaching of F centers in the KCl crystal with incident ultra violet lights in the region of the fundamental absorption band was obtained to have five times larger value than that with the visible light in F-absorption region. With the estimation of the absorption coefficient of the crystal at the fundamental absorption tail, it is infered that one exciton can bleach at least six F centers. From the similar experiments to measure the quantum efficiency for the process of U→F transformation using monochromatic lights, it is concluded that one exciton is able to transform about three U centers. Dependence of the quantum efficiency on the wavelength of exciting light was determined in the KBr crystal.

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The superlattice formation in the alloy CuAu₃ containing 75.0₆ atomic per cent gold was studied by measurements of electrical resistivity and by means of X-ray diffraction with a single crystal. After the alloy was quenched from 450°C, the isothermal change in resistivity was measured at various temperatures between 100° and 220°C. In most of the isothermal measurements, the resistivity increased monotonously with the time of annealing, possessing an activation energy of 25±2 Kcal/mol. It was found, however, that after prolonged annealing at 162 and 175°C sluggish decrease in resistivity took place following initial increase. The transition point of this alloy was determined as 200±5°C.
Corresponding to the resistivity measurement, X-ray diffraction patterns were taken at various states of ordering at 100°, 150° and 180°C as well as at the states quenched from 210° and 450°C. It was confirmed that nucleation and growth of small anti-phase domains in the disordered lattice take place in accordance with the rise in resistivity, and that the development of order within the domains plays an important role in the reduction of resistivity. Then even after three months annealing at 180° and 100°C, the ordered alloy CuAu₃ has a two-dimensional, rather than one-dimensional, anti-phase domain superstructure with the linear dimension of nearly 11 times the fundamental face-centered cubic cells. In every stage examined, the main lattice reflections were surrounded by fairly strong diffuse scatterings, which is considered to be caused by the thermal motion of atoms, not by the lattice distortion due to ordering. Finally, comparing with the alloy Cu₃Au, the change in resistivity due to ordering was discussed in connection with the result of X-ray study.

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The electrical resistivities of arc-evaporated carbon films were studied. The resistance has a large negative temperature coefficient. The annealing diminishes remarkably both the resistance and its temperature dependency. The specific resistivity depends on the film thickness and increases rapidly below 500Å. It seems that the lattice imperfections play the most important role, and then from the annealing curve, their distributions are discussed. The aging effect on the resistance were also measured.

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The electrical resistivity, Hall coefficient and thermoelectric power were investigated over the temperature range from 100° K to 800° K on pure and impurity-doped SnSe crystals. An anomalous hump of the Hall coefficient was found to occur at about 200°C in most of the as-grown crystals and this seems to make the conventional analysis based on a simple semiconductor model impossible. Anisotropies in the resistivity and Hall coefficient were also studied on single crystals and the observed anisotropy in the resistivity seems to be ascribed to an anisotropy in the effective mass of holes. Hole mobility varies as T^−2.0 at high temperatures and its discrepancy from T^−1.5 law is explained on the assumption of both optical and acoustical mode scatterings. Further investigation was made of the anomalous Hall coefficient on heating the specimen at various temperatures in vacuum. This anomalous phenomenon was found to depend on the heat-treatment history of the crystal and the experimental results were analysed on such a simple model that acceptors are introduced into SnSe by impurity diffusion above 200°C and caused to disappear on heating at lower temperatures. General features observed seem to be in fair agreement with the proposed model.

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Polarimetric study of very thin dielectric surface layers on dielectric substrates has been most frequently based on Drude’s theory, or on Sissingh and Groosmuller’s theory obtained by improving the approximation of Drude’s calculation. These theories are derived by modifying the boundary conditions for Maxwell’s equations. A quite different approach to this problem is possible, however, which is based on discussions concerning the interference of light inside the surface layer.
It has been proved by several workers that Drude’s theory is consistent with the interference theory. It is proved in this paper that Sissingh and Groosmuller’s theory is also consistent with the interference theory. Some formulae derived in the process of proof are believed to be useful for further discussions in this field.

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A technique making a sheet of replica which casts two surfaces simultaneously is described. This was successfully applied to the alkali halide crystals which were rubbed gently with velvet or which were irradiated either with x-ray or with ultra-violet light. With using such a replica, it was possible to obtain the informations regarding to the effects which were induced by these treatments inside the crystal just beneath the outer surface, and it was also possible to measure with precision the depth in which region these treatments influenced. The results obtained were also described.

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Nuclear magnetic resonance of the water molecules sorbed on the native cellulose, “mulbery paper” was studied.
The measurements of the line width were made under the condition of water content ranging from 10 to 180% at 20°C, by using Varian high resolution type spectrometer.
Within the range of 10 to 20%, the line widths rapidly decreased with increasing water content, and gradually decreased beyond the region. Although this tendency was similar to that of dielectric relaxation, the experimental value of τ_N obtained from Kubo-Tomita equation was much greater in the order of magnitude than that of the dielectric relaxation time τ_D. Accordingly, τ_N and τ_D do not satisfy the BPP’s relation of τ_N=1⁄3·τ_D. This result suggested to us that the water molecules in the sorbed state do not rotate with spherical symmetry like in the liquid state.

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A phenomenological theory of the non-linear visco-elasticity of three dimensional bodies is presented. We start from the two elementary models of the classical linear theory of visco-elasticity, that is, the so-called Maxwell and Voigt models. These models are extended to three dimensional non-linear case by adopting the energy consideration. The three dimensional Maxwell model is defined by “series connection” of a “non-Hookeian spring”, i.e. the internal elastic mechanism and a “non-Newtonian dashpot” the energy dissipation mechanism, and the three dimensional Voigt model is represented by the “parallel connection” of these mechanisms. Making use of the Maxwell model, we discuss the tensile viscosity for the stationary simple elongation of elasticoviscous liquids. Our models are shown to be successful in analyzing the so-called normal stress effects, i.e., the Weissenberg effect for elastico-viscous liquids and the Poynting effect for visco-elastic solids. The non-linearity in visco-elastic properties is classified into three cases: elastic, viscous or relaxational, and geometric non-linearities. An essential feature of the three dimensional bodies is the geometric non-linearity. The typical examples of this are the said normal stress effects and the velocity gradient dependence of the tensile viscosity coefficient.

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We study the characteristic features of single, double and triple bonds between carbon atoms by idealizing the problem to the electronic structure of fictitious diatomic molecules ≡C–C≡, =C=C= and –C≡C–, where the “open” bonds of carbon atoms are represented by a suitably hybridized orbitals, associated with free spins. Thus, adiabatic potentials are non-empirically and numerically computed and bond energies and equilibrium internuclear distances are evaluated. We obtain 3.1 e.v., 1.25 e.v. and 0.20 Å, 0.10 Å for the values of relative bond energy differences and bond distance differences of single and triple, double and triple bonding. The corresponding experimental values are 2.9 e.v., 1.0 e.v., and 0.34 Å, 0.12 Å respectively.

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In a many-electron system, one is faced to some difficulties when one-electron wave functions are not orthogonal to each other. For example, the inner product (Φ, Φ) (Φ is a Slater determinant made from these non-orthogonal wave functions) loses its meaning as the number of electrons becomes large. We avoid this difficulty by using the expansion coefficients instead of the inner products, in order to define the matrix elements of operators. Applying this method to a magnetic problem, in which there are some doubts about the validity of the Heisenberg model \mathscrH=−2∑_i>jJ_i,jS_i·S_j, we can derive the energy of the ground state and the energy spectrum of spin waves. The results are written as
W₀=∑_i=1^Nf_i,j+\frac12∑_i∑_j(g_ij,ij−g_ij,ji),
and
ε(K)=∑_j=1^Nα_K(j)β_K(j).
Some mathematical difficulties which occur in the case of the state in which more than two spins are reversed are discussed.

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Constant resistance hot-wire anemometry has been improved to measure velocity fluctuation quantitatively. For this purpose, the effects of the resistance of the galvanometer circuit and current variation due to resistance variation of hot-wire are calculated for general case. The values of the turbulent energy reached by the older method would be several part of correct ones in our experiment. A direct calibration method using alternating current has been devised. This method is easy to apply. Experiments show that the results obtained by the two methods completely agree with each other. Owing to the possibility of the calibration in the actual circuit, the constant resistance method would be superior to the constant current method.

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In order to carry out accurate measurements of absorption coefficient by Sabine formula, the assumption of diffuse distribution of sound energy in the reverberation chamber must be fulfilled. Thus, this work was started from the basic researches of the sound field in the two and three dimensional model rooms.
The standing wave pattern of each normal mode was investigated using the dust figures and other methods.
At low frequencies, normal mode of vibration existed even when the room shape was made adequately irregular, and for each normal mode, spatial variation of sound pressure did not depend on room shape.
However, as the room shape becomes irregular, the nodal lines of successive normal modes distribute at random in space. Also, in the properly irregular room, the variation of decay rate for each normal mode was much smaller than that of a rectangular room.

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