Spin wave modes in a thin ferromagnetic film are discussed by considering the non-uniformity of the film. A simple assumption of a parabolic inhomogeneity in an effective field is shown to give a satisfactory prediction of an actually observed spin wave resonances in thin ferromagnetic films. This assumption also leads to the fact that the spin wave modes are expressed by the solutions of the Weber equation, and in the extreme case of ξ₀²>>q the solutions become the wave functions of a harmonic oscillator and in the case of ξ₀²<<q they reduce to the wave functions of a plane wave, where q denotes the number of the modes and ξ₀ denotes the ratio of a film thickness to the degree of inhomogeneity.

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Magnetic coercivity, its temperature dependence and saturation remanence (remanent magnetization remaining after the application of a field of 17 kOe) of cobalt precipitated particles in copper-cobalt alloy containing ca. 2 wt % cobalt were measured as a function of aging time. A coercive force and a remanence field (required to reduce a magnetic remanence to zero) are interpreted in terms of magnetocrystalline and shape anisotropies, and particle-size dependence of the coercive force is discussed in terms of thermal fluctuation of magnetic moment of cobalt single domain particles. Distributions of shape and size of magnetic particles were determined by magnetic analysis. It was found that the axial ratio of the particles increases with aging time.

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Chemical shift and spin lattice relaxation times are measured for Cl³⁵ in all the alkali chloride crystals and for Br⁸¹ and I¹²⁷ in some of the halides. These measured values cannot be explained by using Kondo-Yamashita’s theory alone which takes into account the effect of overlap between the central ion and the nearest neighbors. For the chemical shift, it seems that the overlap with the second nearest neighbors is an essential cause of the discrepancy and that the covalent and the electrostatic effects are rather small. If these conclusions are admitted, there must be a large chemical shift (about −2∼−3×10⁻⁴) of chlorine ion in aqueous solution relative to the free chlorine ion. A model combining the electrostatic and the overlap effect is proposed to explain reasonably the relaxation times in the crystals. The electric quadrupole coupling in free molecules of alkali halides is also discussed from the present viewpoint. The combination of the electrostatic and the overlap effects seems to give a reasonable explanation for the observed values.

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Electrical properties of n- and p-type lead telluride have been measured under high hydrostatic pressure up to 7,000 kg/cm² at room temperature. From the behaviour of p-type samples, it is evident that the edge of a valence band having a lower mobility than ⟨111⟩ valleys occurs at an energy about 0.05 eV below the edge of the band of ⟨111⟩ valleys. It has been found that the energy difference between the bands changes with pressure obeying such a relation as dΔE⁄dP=6×10⁻⁶ eV/kg·cm⁻², so that the effect of the lower mobility band on conductivity becomes less important at high pressure. On the other hand, in n-type crystals the existence of another band except for the ⟨111⟩ valley band has not been confirmed in the conduction band. Change in carrier mobility with pressure is mainly due to pressure dependence of effective mass which is represented by such an equation as dln\barn⁄dP=−2.1×10⁻⁵/kg·cm⁻². Pressure derivative of energy gap dE_g⁄dP has been calculated to be −7×10⁻⁶ eV/kg·cm⁻² from the data of nearly intrinsic samples.

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The relaxation times for electrons in germanium and silicon were measured from the half-width of the cyclotron resonance line at 6 mm wavelength over the temperature range from 1.6° to 20°K for the specimens of different impurity concentration. Above 3°K the reciprocal relaxation times for electrons in high purity specimens are 1⁄τ₀=3.6×10⁸ T^3⁄2 sec⁻¹ for germanium and 1⁄τ₀=2.6×10⁸ T^3⁄2 sec⁻¹ for silicon, respecitively. These results show that the acoustical lattice scattering is predominant in this region. For impure specimens, deviation from the T^3⁄2-dependence was observed at low temperatures. This deviation is due to neutral impurity scattering. The applicability of Erginsoy’s formula for neutral impurity scattering was examined. It was found that the conventional Erginsoy’s formula corrected for chemical shift agrees fairly well with the experimental results.

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The visible radiation emitted from the single crystals of NiO, CoO and MnO by the fast electron bombardment is investigated. The spectral distributions, the angular distributions of the intensity, the polarization characteristics of the emitted light were measured. The experimental results are discussed in view of the theoretical prediction of the transition radiation as well as other possibilities caused by the fast electron bombardment. It is concluded that this radiation is the transition radiation predicted by Frank and Ginsburg.

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Seven Raman lines of the tetragonal BaTiO₃ single crystals, excited by the Hg–c line, have been observed at 359, 416, 502, 513, 736, 823 and 1181 cm⁻¹ from the c-line. The three lines of higher frequencies are interpreted to be corresponding to the lattice vibrations of higher mode. A possible explanation of the four lines of lower frequencies is presented as corresponding to the fundamental modes of vibration in tetragonal BaTiO₃. A possibility is pointed out that the “ferroelectric mode” splits into two species, of which frequencies are near 340 cm⁻¹ and near 34 cm⁻¹, respectively. The Raman line located at 359 cm⁻¹ is interpreted to be corresponding to the former species.

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The effect of atomic ordering on the magnetic properties of Fe-Al alloys has been studied for the specimens with different compositions. The so-called “double-Curie point” phenomenon has been studied at a magnetic field strength of 242 Oe: the behavior of the magnetization in this temperature range is different from that observed at lower magnetic field strengths, and Pál and Tarnóczi’s interpretation, which is based on the demagnetizing field caused by the formation of a finely dispersed paramagnetic Fe₃Al ordered phase, cannot apply to this case. There is some evidence that the Curie temperature of FeAl ordered phase is higher than that of Fe₃Al ordered phase, and at high Al concentrations both of these temperatures are lower than the Fe₃Al-FeAl transformation temperature. The difference in the paramagnetic behavior between the FeAl ordered phase and disordered phase has been observed and discussed.

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Microwave absorption has been observed in n and p-type lead telluride as a function of static magnetic field at 1.8°K and 70 kMc/sec. Magnetic field B used in most cases was parallel to the sample surface. The derivative dP⁄dB of microwave absorption versus B was measured as a function of crystal orientation. The anisotropy of the effective mass of electrons is similar to that of holes in the (100) plane. The modes of microwaves are investigated in the high density plasma whose Fermi surface is assumed to be [111] prolate spheroids. A close fit to the experimental data is obtained from theoretical calculation with the values of the transverse mass m_t=0.024 m₀, 0.030 m₀ and the mass ratio m_l⁄m_t=K=10, 13 for electrons and holes respectively.

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Wave-optical principles of electron and X-ray diffraction in distorted crystals developed in Part I are applied to Laue cases where only one diffracted wave is excited appreciably. Using the two-beam approximations, it can be shown that the trajectory of a “modified Bloch-wave” is determined by a differential equation which has an analogous form to a special-relativistic equation of motion for a charged particle in an electric field. The apparent force which changes the direction of motion is caused by lattice distortions. The phase change along the trajectory is obtainable by the phase integral given in Part I. The amplitudes of the direct and the diffracted waves are given by considering the compatibility of crystal and vacuum waves as to the energy flows on the crystal boundaries. The boundary conditions are discussed for electron and X-ray cases separately. Pendellösung fringes are expected for both cases from an interference between two modified Bloch-waves corresponding to the different branches of the dispersion surface.

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Chemisorption studies have been made in a closed system by a mass spectrometer operated statically. Nature of molybdenum surface was changed in a short duration. The total saturation coverage is 1.2₅×10¹⁴ molecules/cm² and is nearly equal to that for tungsten. A weekly bound adsorption state corresponding to the α-state of tungsten does not exist for molybdenum. Chemisorption states of two types are found; ζ is 35% of the total saturation coverage and is a dissociative chemisorption of which the heat of chemisorption is 2.7₅ eV, and ε is 65% and a non-dissociative chemisorption of 3.1 eV. The average sticking probability is 0.2 at low coverages. Generally, behaviours of molybdenum for nitrogen chemisorption are very resemble to that in the case of tungsten.

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The microsocopic studies of N₂ on W have been made and compared with the results of the macroscopic studies. The sites of the non-dissociative chemisorption ε exist on and around the (111) plane and around the (011) plane, and the ε-adatoms increase the work function of these planes as much as 0.5 eV. While, the sites of the dissociative chemisorption ζ are on and around the (001) and (111) planes, and the work function is lowered as much as 0.2 eV by the ζ-adsorption. The situation of the α-site is not determined because of its small amount.
The previous studies of the work function change are interpreted reasonably by the αεζ-model without the suspision of impurities. These interpretations entirely differ from those of Ehrlich et al. by the αβ-model.

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A statistical mechanical theory of steady viscosity in bulk polymers is presented. In slowly relaxing phenomena such as steady viscosity, the inter-chain relaxation is predominant and the segmental conformation of each polymer molecule attains to a state of dynamic equilibrium. It is assumed that the intermolecular force between two molecules consists of two parts: the force derived from potential and the friction due to entanglements between them. The general expression of viscosity is derived from the fundamental equation for the velocity distribution function of a polymer molecule, using Born-Green’s method.
The molecular weight dependence of viscosity η is roughly estimated by taking into account the inner structure and conformation of polymer molecules. The result is η=C₁N+C₂N³, where N is the number of segments constituting a polymer molecule, C₁ and C₂ are constants, and C₁>>C₂. This prediction agrees semi-quantitatively with experiment.

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Viscoelasticity of network structure is investigated using the Rouse model corresponding to macro-Brownian motion. The viscous and elastic effects between chains are introduced and a slip equation determining the slip rate of chain and the stress are obtained in a clearer form than in the preceding report. Stress relaxation, stationary simple elongation, stationary flow and periodic shear deformation are treated. The relaxation spectrum given by the theory is of the box type and the viscosity coefficient and the time rate of energy dissipation are proportional to the 3.4th power of molecular weight.

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The connection formula given in Part I, which unifies the impact and wave theories, is generalized so as to make quantum mechanical calculation possible. A relaxation rate X is given in the form
X=X_κ+X_wave−X_wave,κ.
Here X_wave is the quantity calculated in the wave theory; X_wave,κ is the quantity to which X_wave is reduced when the dielectric permeability is replaced by 1+κ²⁄k², which depends on the wave number k only; X_κ is the quantity calculated in the collision theory with use of the screened Coulomb potential of the form e^−κr⁄r; and κ⁻¹ is any length considerably longer than the close impact radius. The final result is independent of κ. Applications are given.

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Pulsating laminar flow superposed on the steady motion of a viscous incompressible electrically conducting fluid in an annular channel between two infinitely long circular cylinders under a radially impressed magnetic field is considered. The general magnetohydrodynamic equations are simplified to three equations in pressure, velocity and magnetic field. One equation gives the pressure variation in the radial direction; the other two are coupled equations for the velocity and magnetic field, which are functions of the radial variable only. The solutions of these equations have been obtained in terms of Kelvin and Lommel functions on the assumption of small electric conductivity and the velocity profiles are examined for different values of the frequencies of pulsation.

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This paper pertains to a study of motion in a three-dimensional periodic boundary layer when the frequency of the external stream is large. The general form of additional pressure gradient due to oscillations is obtained, which describes the effect of curvature terms in the equations of motion, on the periodic boundary layer flow.

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Another exact solution of the Navier-Stokes equations of motion is discussed corresponding to the flow of a viscous incompressible fluid in the annulus between two coaxial cylinders when the walls are porous and allow suction and injection at a rate varying linearly with distance from some fixed point on each of the walls.
Some interesting new phenomena arise in this case, for example, the fluid can flow by this suction and injection alone in the absence of the motion of the walls and/or a pressure gradient. Another interesting result is that if the walls move in one direction, portions of the fluid can move in the opposite direction.
The modifications in the flow when the fluid belongs to a class of Non-Newtonian fluids have also been discussed.

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p. 485   The evuation “V=\fracac²2” should be read “V=\fraca²c2”.
p. 486   The value of the lattice summation, 3.5, should be changed to −2.95×10⁻² and the value of 2.7 in Eq. (17) should be changed to −7.95×10⁻². The proposed explanation of Cloud’s result must be changed.

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On page 1488, line 1 and also in Eq. (13), ⟨φ_k|H₁|φ_k⟩ should be replaced by ⟨φ_k|H₁|φ_k′⟩. On page 1489, left column, the elements at row 1, column N and at row N, column 1 of the determinant on the right-hand side of Eq. (25) should read zero instead of β. On page 1493, right column, line 28 should read “D₂O (99.9%) and H₂O (0.1%) at 4°K through ···”.

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