The angular distributions of alpha particles elastically and inelastically scattered by Sn, Cd, Ag, Cu and Ti have been measured at 28.4 MeV. For Sn, Cd and Ag, the angular distributions of the prominent groups corresponding to the quadrupole and octupole excitations were fitted by calculations based on Blair model in a preliminary step. The angular distributions of the groups near 1.22 MeV in Cd and near 0.90 MeV in Ag were found to have an intermediate phase between the corresponding elastic distribution and the distribution for the quadrupole excitation. The angular distributions for the inelastic scattering leading to various states of Cu and Ti were also obtained. Discussions are also presented based on the results of the DWBA analysis.

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A new diffusion mechanism is suggested to interpret the remarkable deviation from the Einstein relation observed in the diffusion of silver ions in the high temperature forms of Ag₂S and others. The essential feature of the proposed mechanism lies in admitting the cooperative jumps of two or more ions.

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On the basis of the Feynman model for polarons, the drift mobility of an electron in a polar crystal is studied for the weak coupling limit of the electron-phonon interaction. The expression for the polaron mobility at the low temperature limit, which was previously obtained by the author, is extended to the case of the finite temperature. The analysis of the experiments with AgCl and AgBr showed that the expression thus obtained gives a smaller band mass than other methods of analysis of the drift mobility (Van Heyningen and Garcia-Moliner) do.

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Thermomagnetic properties of Mn_3−xMe_xB₄ (Me=Ni or Co; 0.36≥x>0) were investigated in the temperature range from −196°C to 300°C. The antiferromagnetic characteristics of these compounds are almost similar to those of the parent compound Mn₃B₄ at high temperatures, and a monotonic decrease of the Néel point is observed depending on the amount of Ni or Co present. With decreasing temperature, however, the susceptibility undergoes a transition to ferromagnetic state, and exchange inversions are observed at temperatures between −140°C and −10°C depending on the value of x in the formula. Magnetizations of these compounds are unsaturable even under the field of 18,000 Oe and are as large as 30∼40 e.m.u./g. From the results of the present experiment, the spin assignment in Mn₃B₄ is discussed again. It is concluded that manganese atoms on 4(g) exclusively can contribute to the magnetism.

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Magnetic susceptibilities of the primary solid solutions of Cr with Mn, Fe or Co were determined. The results are analysed by taking into account the impurity band which is essentially important for the interpretation of the electronic structure of the solid solution. The legitimacy of the rigid band approximation is confirmed for Cr–Mn series. In Cr–Fe and Cr–Co series, the excess electrons of the impurity atoms are localized and polarized so as to give localized magnetic moments of 2.8 μ_B and 2.9 μ_B on Fe and Co atoms respectively. Their transition temperatures were determined by measurement of the electrical resistances and thermal expansivities. Their composition dependence is explained qualitatively on the model of the energy bands derived from the analysis of their magnetic susceptibilities.

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Magnetization of a single crystal of α-Fe₂O₃ was measured in a magnetic field up to 80 kOe in the temperature range below the Morin transition point. From the experimental results and Clapeyron-Clausius’ equation, the entropy change at the transition, ΔS, and the pressure dependence of the Morin point, (dT_M⁄dP)_H, were found to be as follows:
ΔS=0.6×10³ erg/deg·gr,
(dT_M⁄dP)_H=17×10⁻⁹ deg/dyne·cm⁻².

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Spectral dependency and electric field dependency of photoconductivity of purified TlCl have been studied at low temperatures, mostly at 17°K and 81°K, by the standard transient method with blocking electrodes and using exciting light of low intensity. When traps in the crystal are empty, higher photoresponses under hole polarity than those under electron polarity have been observed at 17°K and vice versa at 81°K, indicating that the photoconductivity is of two-carrier. The results are analyzed from the standpoint of two-carrier and low field unit ranges of electrons and holes are determined. With these unit ranges, schubwegs of electrons and of holes are estimated as functions of electric field from the field dependence of photoconductivities under both polarities. They obey Ohm’s law at 81°K but are proportional to E^0.5 above certain critical fields at 17°K. Low field unit range of holes has been found to be larger than that of electrons below 50°K and smaller above this temperature. Effect of filling traps to unit ranges and a contribution of surface layer to photoresponse have been investigated. Electrical glow peaks have been observed at 63°K and 85°K.

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Nuclear magnetic resonance of Co⁵⁹ in polycrystalline Co₃O₄ and ZnCo₂O₄, and Al²⁷ in CoAl₂O₄ in paramagnetic state was observed. The cobalt signal was identified with the Co³⁺ ions at the octahedral sites of the spinel structure. The line shift of Co⁵⁹ in Co₃O₄ was separated into two terms: temperature-independent and temperature-dependent ones. The temperature-independent shift (1.5%) is interpreted as the second order chemical shift due to the mixing of the low lying excited state. The temperature-dependent shift is attributed to the hyperfine coupling between the cobalt nuclear spin and the electron spins on the Co²⁺ ions at the tetrahedral sites. The isotropic hyperfine coupling constant A is estimated at 13×10⁻⁴ cm⁻¹. The results on ZnCo₂O₄ and CoAl₂O₄ give supports to the above interpretations. The line shapes were studied and the thermal relaxation time T₁ was estimated to be 1.5×10⁻⁵ sec.

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Theoretical calculation has been made on high-frequency transport properties of InSb under a d.c. magnetic field, leading to the conclusion that the relative increase of microwave loss in InSb under a magnetic field, γ_l, is given by γ₀{1+ω(τ_e+τ_h)}, where γ₀ is the relative resistivity increase Δρ⁄ρ₀ under a d.c. magnetic field with d.c. current, and τ_e and τ_h are the constant relaxation times for electrons and holes respectively. Measurements were made on the microwave power loss at 34 Gc/s at room temperature under magnetic fields up to 1.5 weber/m². The experimental results show an appreciable influence of ωτ on the loss even at room temperature as predicted by the theory.

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Magnetic studies were made on the compound (Mn_1−xCr_x)₃B₄, x ranging from 0 to 0.5. In the composition range 0≤x≤1⁄3, antiferromagnetic phase of Mn₃B₄ and ferromagnetic phase of Mn₂CrB₄ were found to be stable, and these two phases seemed to coexist for the intermediate compositions. A rotational hysteresis was observed with the specimen for which x=0.05. This was attributed to the exchange interaction at the boundaries of these phases.

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The forbidden hyperfine transitions in the paramagnetic resonance spectrum of Mn⁺⁺ are observed in single crystal and powder samples of cubic CdTe and CdSe. The data of the paramagnetic resonance observation on six chalcogenides of zinc and cadmium are summarized, and the intensity of the forbidden transition J and the separation of the forbidden doublet δH are discussed in terms of the covalence of the compound. It is shown that r_L⁄{(\sqrt3⁄4)a_o+α}, where r_L represents the anion radius, a_o the lattice constant and α a correction term, is a useful parameter for the analysis of J and δH.

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Theoretical study is made of the nuclear magnetic resonance shift of a Co³⁺ ion at the B site in Co₃O₄. The temperature-independent part of the shift is attributed to the chemical shift of the Co³⁺ ion. From its analysis it is concluded that the Co³⁺ e_g orbital is radially expanded relative to the d orbital of the free ion and that the e_g electron spends about 30% of its time on the surrounding oxygens. The temperature-dependent shift is explained by the transferred hyperfine interaction between the Co²⁺ magnetic moment and the Co³⁺ nuclear spin which arises from the 0.2% mixing of the Co³⁺ 4s orbital into the oxygen 2s and p_σ orbitals. It is shown that the shift due to the mixing of the Co³⁺ e_g orbital is opposite to the observed one and ten times smaller than it. Finally superexchange mechanisms in Co₃O₄ are examined. It is concluded that 2% fractional spin density in the Co³⁺ e_g orbital mainly contributes to the superexchange.

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The existence of the temperature dependent “soft mode” in a perovskite-type ferroelectric crystal has been concluded from the temperature independence of the frequency ν_m, at which reflectivity assumes minimum, by using the classical dispersion relation of the single-oscillator model. The temperature dependence of the “soft-mode” frequency of several crystals has been calculated and compared with experimental results. The temperature dependence of reflectivity spectra in far-infrared and infrared regions has been computed, where a certain temperature dependence of the damping constant was taken into account. The existence of the “soft mode” in the ferroelectric phase, the over-damping effect and some other phenomena are discussed.

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A quantum field theoretical method is applied to the dynamical theory of X-ray diffraction. Diagrammatical methods for the calculation of the Green function, which have been developed in the field of many body problems, give usual scattering factors and absorption coefficients. It is also shown that the usual dispersion equation can be derived from the pole of the Green function.

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The excitation cross-sections for the rotational and the vibrational transitions are calculated on the basis of the Born approximation combined with the point-dipole interaction. This calculation is partly the reconfirmation and partly a slight extension of the previous treatments. The validity of this treatment is examined. It is concluded that the treatment is not applicable for the incident energies around and above 1 eV because of an effect of large distortion in the wave function of the scattered electron. Possibilities of improving the theory are briefly discussed.

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A relaxation equation for the velocity distribution of the ions in a plasma is derived from the convergent kinetic equation taking account of both the short-range and collective interactions. The equation is solved by expanding the distortion of the distribution from equilibrium into a series of orthogonal polynomials. The rate of relaxation of each mode is obtained exactly without any cut-off procedure. The Coulomb logarithms in the rates of each mode are different from each other.

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The steady motion of a non-Newtonian liquid through two coaxial curved pipes is discussed on assumptions and approximations similar to those taken by Jones for the case of a single curved pipe. Many theoretical results are supported by numerical calculations.
Discussions are made amongst others about (i) the relation between the pressure gradient and the rate of outflow (to the first order of approximation in the curvature), (ii) the secondary flow produced by the curvature of the pipes, and (iii) the effect of the curvature and the cross-viscosity parameter S on the stress components on the boundaries. The streamlines in a normal section are plotted for some different values of S. The corresponding results for the Newtonian liquids follow when S=0.

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The heat transfer in fully developed laminar flow of Bingham material in an annulus between two coaxial pipes is discussed. The inner pipe moves parallel to itself and the outer pipe is at rest. Equations for temperature distribution including the effect of dissipation and internal heat generation have been set up and a discussion of the solution is given for the case of small gap approximation. The temperature distributions are found to depend on Bingham number (or the position of yield surface), Brinkman number and the rate of heat transfer at the wall. The effect of dissipation is to increase the temperature at a place and this effect becomes greater as the region of flow becomes narrower. There exists a critical value of the Brinkman number above or below which the cooling or heating of the outer pipe takes place.

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The functional formalism for turbulence mechanics originated with Hopf is generalized in such a way that it can embrace a space-time correlation tensor of turbulent fields, i.e. correlation tensor between non-simultaneous fields, and furthermore any external random forcing field can be taken into account in the formalism. The first work in this direction was recently done by Lewis and Kraichnan, but here the theory is more compactly and generally developed together with the deduction of a general solution of the full basic functional equations in terms of functional integration.

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The stability of a natural convection which takes place in a fluid between two parallel vertical planes kept at different temperatures is investigated. The Boussinesq approximation which is used in this work enables Squire’s theorem to hold good in this problem, and the lowest value of the critical Reynolds number occurs with two-dimensional disturbances. The critical Reynolds number is found to be 7.7×10⁵ irrespectively of the changes in the Prandtl number in a moderate range.

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