A unclear resonant scattering experiment was carried out of the lead capture gamma rays from natural zinc. The ground-state transition width of the 7368-keV resonance level was measured by means of self-absorption and temperature variation. The width Γ₀ and the separation energy between source and target levels δ were found to be 0.22±0.02 eV and 8.5±_0.5^0.7 eV, respectively.

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The elastic scattering of ³He particles from ⁵⁸Ni at 24.15, 27.64 and 34.14 MeV has been studied. The measurements were done at laboratory angles extending from 15° to 170° at 2.5° or 5° intervals. An optical-model analysis was carried out with an automatic search code. Both Wood-Saxon potential and derivative Wood-Saxon potential were applied to the imaginary part of the optical potential. The latter gave better fit than the former at backward angles when a spin-orbit coupling potential was not used. An analysis using the optical potential with Thomas type spin-orbit coupling was also carried out. The depth of spin-orbit coupling potential depends on the depth of the real potential and the different potentials that minimize χ²⁄N for the cross section give similar polarizations. Ambiguities in the optical-model parameters appear in all the present analyses.

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A general expression of the interaction energy between fluxoids and lattice defects is obtained by perturbational calculations of the generalized Ginzburg-Landau equations, which are derived by minimizing the free energy of the mixed state including elastic terms. The present expression is the same as Labusch’s obtained only for a special type of lattice defects with a pure shear, but is shown to be applicable to any type of defects.
The interaction force between a fluxoid and a lattice defect is derived for some typical types of defects by the use of the present expression of interaction energy, and the results of previous authors are shown to be unsatisfactory, even qualitatively. The present results give the first step for the derivation of a general expression of the so-called “pinning force”, which is the final purpose of this series.

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The magnetic susceptibility (χ) of several highly conductive TCNQ complexes was measured in the temperature range from 2.5°K to room temperature. χ is composed of diamagnetic part (χ_d), a paramagnetic part (χ_c) caused by crystal imperfections, and an intrinsic paramagnetic part (χ_p). Three parts can be separated unambiguously, provided that χ_c obeys Curie’s law and χ_p approaches zero as temperature is lowered.
χ_p of Et₃NH(TCNQ)₂ below 300°K and that of DAD(TCNQ)₂ below 30°K are well explained by one triplet state per four TCNQ molecules at 310 cm⁻¹ and 120 cm⁻¹ above the ground singlet, respectively. Temperature dependence of χ_p of DAD(TCNQ)₂ from 30°K to 300°K cannot be explained quantitatively, though χ_p tends to coincide with that of undegenerated electron gas at high temperatures.
For Q(TCNQ)₂, BiP(TBNQ)₂ and NMePh(TCNQ), χ were unsuccessfully separated, since χ_c deviated from the Curie’s law owing to the high concentration of impurities in the samples.
These results are discussed with the results of far infrared absorption spectra of these materials at 300°K and 1.5°K.

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The calculation of the anisotropy energies for Ni and Fe metals is performed with use of the perturbation theory, on the basis of the energy bands given by Yamashita et al. The spin-orbit interaction is taken into account in the tight binding approximation up to the fourth and sixth order perturbations. The first and second anisotropy constants K₁ and K₂ at 0°K are estimated to be −4.6×10⁵ ergs/c.c. and −0.5×10⁵ ergs/c.c. for Ni metal and 6.0×10⁵ ergs/c.c. and 1.2×10⁵ ergs/c.c. for Fe metal, respectively, where the values of the spin-orbit interaction constants are adopted as 350 cm⁻¹ for Ni metal and 230 cm⁻¹ for Fe metal. The calculated temperature dependences of these anisotropy constants are qualitatively in agreement with the experimental results, and explain the experimental results of the anisotropy constants K₁ and K₂ at room temperatures.

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Spin wave resonances in thin Permalloy films were measured as a function of the angle between the external field and the film plane. In the case of thin films 600Å in thickness, resonance can be observed in the whole range of the angle. In the case of thicker films, some modes disappear at different angles which are close to 90° for the higher modes. The disappearance is closely connected with the broadening of the line width. This broadening is more marked for the higher modes, and can be well explained by a theory in which the Gilbert damping and the static equilibrium condition are taken into consideration.

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Magnetic and crystallographic natures of compounds Mn_1−xCr_xAs (0.3≥x>0) were studied in the temperature ranges from 4.2° to 900°K and from 100° to 320°K. The compounds had MnP-type (B31) structure at low temperatures and transformed into NiAs-type (B8₁) structure at high temperatures. These compounds were metamagnetic at low temperatures. It was further confirmed that the deformation induced a low spin state of metal ions in the compounds, while with decrease in deformation due to the rise of temperature, the metal ions in the compounds transfer to a high spin state, as in the case of MnAs_0.9P_0.1.

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Pressure dependence of spontaneous magnetization and forced- and spontaneous-volume magnetostriction in itinerant electron ferromagnets at 0°K are formulated. Dependence on atomic volume of the band width and of the molecular field coefficient are taken into account. It is shown that the spontaneous volume magnetostriction, ω_s, must be negative when the forced one, ω_H, is negative while the former may be positive or negative when the latter is positive. It is easily understood why ω_H is positive or whereas ω_s is negative in Ni, Fe and some Ni–Fe alloys. If Kanamori’s theory considering the correlation between electrons is applied to the molecular field coefficient, then ω_H is positive at 0°K. So far has been found no metallic ferromagnets with negative ω_H at low temperature, with an exception of dilute Fe–Pd alloys. Diagrammatic representation to relate the density of states to forced- and spontaneous-volume magnetostriction is given.

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With the hope of obtaining information about the canted spin structure which has been proposed by Nakagawa et al. on the basis of their neutron diffraction study, the Mn⁵⁵ NMR frequency has been measured as a function of external magnetic field. A value of (−1.03±0.03) MHz/kOe has been obtained for dν⁄dH at 77°K. This value seems to suggest that β₁-MnZn has a simple ferromagnetic spin structure, if it is not the case that the hyperfine field at the Mn⁵⁵ nucleus lies accidentally along the ferromagnetic component due to the effects of the neighboring Mn moments.
The results of the observation of the Zn⁶⁷ NMR is appended. The hyperfine field at the Zn⁶⁷ nucleus is −270.9 kOe at 4.2°K.

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The dynamical behavior of the sublattice magnetization vectors of an antiferromagnet in a static magnetic field near the spin-flip critical field is studied theoretically. The well-known phenomenological equation of motion, including the Landau-Lifschitz damping term, is solved approximately by an analytical method in the case of an antiferromagnet having orthorhombic anisotropy energy. It is shown that when the applied field is close to the spin-flip critical field, the antiferromagnetic magnetization axis moves slowly towards its equilibrium position and that the motion is governed by an equation of a classical pendulum with viscous damping. It is also shown that a small eigenoscillation is superposed on this large slow motion.

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To study the motion of the sublattice magnetization vectors in the process of spin-flipping the phenomenological equation of motion including the Landau-Lifschitz damping term is integrated numerically for the case of an orthorhombic system CuCl₂2H₂O and a similar system having a larger an isotropy energy, and also for the case of a uniaxial system MnF₂. In the case of small damping the sublattice magnetizations in an orthorhombic system rotate around tend to their equilibrium positions after infinite number of turns, but in the case of large damping they tend smoothly to the equilibrium positions without oscillatory motion. The sublattice magnetizations are almost confined in the easy plane when the applied field is close to the spin-flip critical field, or when the damping is large. In the case of small damping a small eigenoscillation is superposed on the large motion mentioned above. The motion in a uniaxial system differs in that the sublattice magnetization vectors do not easily move towards their equilibrium positions but they perform a spiral motion around an axis that is nearly perpendicular to the equilibrium direction, i.e. where the energy has its maximal value. Fox large damping the motion occurs nearly in a plane towards the equilibrium direction.

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Hall Coefficient of single crystals of pure Zn and Zn–Cu η phase alloys were measured in the temperature range of −196°C∼100°C. Remarkable anisotropy was found not only in pure Zn but also in Zn–Cu alloys, while absolute values of the Hall coefficient decreas with Cu-concentration. The temperature dependences also depend on the direction of the magnetic field.
In order to know the origin of the anisotropy, the contribution from the various parts of the Fermi surface are estimated, partly by calculation and partly by the present data. Consequently, it is suggested that the most heavily distorted part of the Fermi surface is the 1st and 2nd zone hole, and that observed concentration dependence should be interpreted in terms of the 1st and 2nd zone hole.

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Theoretical interpretation of an anomalous behavior of the thermoelectric effect in bismuth is presented. According to Farag and Tanuma, the thermoelectric power has sharp minimum at low temperatures and in high magnetic fields. As an example minimum value for a sample reaches −16000 μV/deg at 18000 Oe. Such an anomalous feature can be explained qualitatively in consideration of the phonon drag effect. Phonon dragged by electrons and holes drifting in the direction perpendicular to electric field and magnetic field, carries Peltier heat. It is verified that the phonon drag component is the main part of the thermoelectric power in high magnetic fields.

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Theoretical explanation of the anomalous feature of the Nernst-Ettingshausen coefficient A_NE in bismuth is presented. Temperature dependence of A_NE is entirely different from the one predicted by a theory ignoring the deviation of the phonon distribution. Coupled Boltzmann equations for carriers and phonons are solved on the weak field approximation. These solutions reveal to us that the phonon drag effect and the indirect interactions of electrons and holes through the phonon drag effect, are responsible for the appearance of the anomalous effect. In strong magnetic field A_NE is related to the phonon drag thermoelectric power derived in the preceding paper. This relation explains the qualitative feature of A_NE at low temperatures.

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The frequency-dependent electrical conductivity of dilute alloys is expressed in terms of the impurity scattering t-matrix which is a function of temperature. The formula is applied to a few model examples for dilute magnetic alloys in which the imaginary part of the t-matrix has a sharp peak at the Fermi level, owing to the scattering by local spin fluctuations of magnetic impurities. The results show significant deviations from the Drude formula; the real part of the complex conductivity can have a peak at a finite frequency.

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Electrical resistivity was measured in copper manganese alloy system with manganese concentration between 0.06 and 5.2 atomic percent in the temperature range from 2 to 300°K. The residual resistivity separated from the observed resistivity, has a maximum at certain temperature which is proportional to the concentration. The maximum arises from a combined effect of the Kondo logT term and the term caused by the effective molecular field due to spin ordering. In the sample with the concentration higher than 1 atomic percent the tail of the Kondo logT term was very large even at a temperature as high as 300°K. This fact enables us to explain the maximum in the concentrated sample.

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It is convenient to grasp crystals of a kind as “ferroelastic” crystals. They are defined analogously to “ferroelectric” crystals, mechanical strain and stress in the former corresponding to electric polarization and field in the latter respectively. The order of magnitude of the coercive stress for ferroelastic state-shifts which corresponds to the coercive field for ferroelectric state-shifts is expected, on the average, to be 10² newt·cm⁻². A determination is made of all theoretically possible species of ferroelastic crystals and the number of states and ferroelectricity or nonferroelectricity in each of these species. It is found that there are 94 of these ferroelastic species and that 42 of them are simultaneously ferroelectric. Incidentally, an alteration is made of the hitherto used symbols for the 88 species of ferroelectric crystals.

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Radiation damages in silicon single crystals irradiated by pile neutrons were investigated by using Hall effect and the carrier lifetime measurements. In p-type silicon donor-like centers were found to be introduced, the energy level of which located at about E_V+0.3 eV. Its introduction rate did not depend on the kind of impurities, carrier concentrations and crystal growth methods. At the small irradiation dose level the minority carrier lifetime was controlled by the recombination through the defect centers. With the increase of dose the trapping effect became remarkable even at room temperature in conjunction with the recombination effect. At 2.6×10¹² nvt irradiation dose the trapping level at E_C−0.16 eV was found to be predominantly introduced. The annealing studies of 2.6×10¹² nvt irradiated p-type silicon indicated that trap centers annealed at around 200°C, subsequently recombination centers annealed at 430∼480°C. Recombination centers annealed over the broad temperature range and did not show any sensitivity to the existence of oxygen impurities. The results were tentatively interpreted on the basis of the model proposed by Gossick.

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The minority carrier lifetime in gamma-irradiated silicon crystals was studied. In F.Z. n type crystals containing phosphorous, arsenic, antimony or bismuth, there are two annealing stages in the temperature range 100–280°C and in both stages there is strong dependency of activation energies E_a and frequency factors on the atomic size of the impurity. The relationship between E_a and covalent radii of the impurity atom can be experimentally expressed in linear functions. The defect which anneals in the lower temperature stage is a complex of donor atoms associated with a vacancy type defect. Si–E center anneals in the higher temperature stage and the values of activation energies completely agree with those obtained by Watkins et al. in their experiments of reorientation of donor-vacancy axis. The defects of both stages are considered to migrate to the sinks of oxygen after jumps of about 10⁵. It is very interesting to note that this study shows only one example of an impurity atom which moves with a vacancy in silicon without breaking up.

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The electron spin resonance (ESR) study has been made for cubic and tetragonal lead titanate (PbTiO₃) doped with manganese ion. The signals were observed in the ceramics fired in nitrogen atmosphere, whereas both for the ceramics fired in air and for single crystals any ESR signal due to substitutional Mn²⁺ was not observed. Mn²⁺ in PbTiO₃ is considered to be located at the titanium site in the unit cell. The spin Hamiltonian parameters obtained are as follows: in tetragonal phase g_⊥=2.084±0.002, D=+(502±4)×10⁻⁴ cm⁻¹, a=+(43±2)×10⁻⁴ cm⁻¹, A_x(=A_y)=−(82±1.5)×10⁻⁴ cm⁻¹, in cubic phase g=1.996±0.002, A_x(=A_y=A_z)=−(79.8±0.5)×10⁻⁴ cm⁻¹. The ratio between the values of D in PbTiO₃ and BaTiO₃ is in rough agreement with the ratio between the strengths of their axial crystalline field.

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Kittel’s free energy expression was normalized to involve only dimensionless variables, and manipulated to explain behaviors of second-order linear antiferroelectrics. It is a function of polar and antipolar variables, each of which are proportional to sum and difference of polarizations of two sublattices respectively, and it contains dimensionless temperature and external field as parameters. Free energy maps as functions of the two variables were computed at various values of two parameters. They visualize stability of states and how induced transition occurs under the external field. Stabilities of states were examined analytically, and restrictions on the two parameters for stability were obtained. Below the transition point antiferroelectric state is always more stable than polar state. Under external field, the well-known double hysteresis loop was explained satisfactorily considering stability of the state on two branches of polarization vs. field. Critical field for induced transition was also calculated as a function of temperature. Relation between susceptibility and temperature showed new behaviors under bias field. Discontinuous change in susceptibility is revealed at the transition point, and susceptibility goes to infinity at a certain temperature and bias field.

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Propagation of surface charge waves in a MOS structure is theoretically predicted and experimentally observed. A magnetic field is applied parallel to the MOS layer and perpendicular to the wave propagation direction. For a given magnetic field, it was shown that the wave can propagate only in one direction. A very large non-reciprocity in the wave propagation was also experimentally observed using n-InSb at 77°K. For example, the transmission voltage was attenuated by 3.5 db in one direction (forward direction), and by 40 db in the opposite direction (backward direction) at a frequency of 1 MHz for the sample used. The forward transmission gradually decreased with increasing frequency and was observed up to 480 MHz. Using the observed values of the wavelength, the phase velocity was calculated to be about 4×10⁷ cm/sec. The phase velocity is expected to be reduced further by increasing the MOS capacitance. Most of the observations agreed with the theory.

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Stress-strain curves of bcc metals at low temperatures, where screw dislocations predominate, are calculated for crystals with the [100] deformation axis. The main assumptions are (1) an increase of flow stress is proportional to the square root of forest dislocation density, (2) dislocations are multiplied by the cuttings of screw dislocations with repulsive elastic interaction, and (3) a screw dislocation annihilates with another dislocation with the opposite sign. The calculated stress-strain curve is compared with the observed stress-strain curves. It is concluded that the important property of screw dislocations in bcc metals is the easiness of cross-slip; this is the origin of the variety of the work-hardening in bcc metals at low temperatures.

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Differential cross sections are calculated for the electron-impact rotational transitions in two polar molecules, CN and HCl, using the close-coupling method. The rotational states l=0, 1, 2 of the molecules are taken to be coupled and the cross sections for the transitions 0→0 and 0→1 are obtained. For 0→1, the calculation shows that: i) scattering is strongly confined to the forward direction, corresponding to the long-range nature of the dipole interaction; ii) when comparison with the Born approximation is made, the Born result agrees well with the close-coupling calculation, especially for small angle scattering. Finally, momentum-transfer cross section σ_m is calculated and it is found that the dependence of σ_m on the dipole moment D is similar to the result obtained in the approximation of fixed dipole; the calculated value of σ_m has a maximum peak at D\simeq1 a.u. and, in the vicinity of the peak, appreciably exceeds the Born estimate.

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The excluded volume effect on the radius of gyration of chain polymers is calculated by assuming that the intramolecular energy is represented by the product of the binary cluster integral of polymer segments and their contact probability.
The expansion coefficient α of polymer can be given by the expression:
α⁵−α³=(134⁄105)zα^X, X=0.4∼1.0,
where z is the usual interaction parameter of segments.
In this calculation if the expansion coefficient α_ij of each subchain is all assumed to be equal to α, X vanishes, but when α_ij is taken to be the increasing function of |j−i|, it becomes positive.
The values of α obtained by this calculation are close to that of the previous theory by equivalent ellipsoid polymer model in the range practically usefull (1\lesssimα²\lesssim3), and they are almost in coincidence with the result of the second or third order perturbation theory for very small |z|.

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The average value of the internal field in the solution of dimethyl formamide in a mixture of benzene and liquid paraffin has been estimated experimentally by measuring its complex dielectric constant ε^* in the x band (λ=3.22 cm) microwave frequency region. The method of Poley (Appl. sci. Res. 4B (1955) 337) is followed for measuring ε^* . The internal field is found to be lower than Lorentz type of field and this difference has been measured as a function of the dielectric constant.

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The transport coefficients of a nonisothermal, full ionized plasma have been determined without any cut-off procedure. The theory is exact in the sense that it is valid not only for large values of the Coulomb logarithms themselves but also for large values of their arguments. The effect of interactions between electrons and plasma oscilations has been incorporated in the theory. External magnetic fields have not been considered.

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The laminar viscous flow near the trailing edge of a flat plate is studied by use of the modified Oseen approximation. Considering that at high Reynolds numbers, the flow region near the trailing edge is immersed in the boundary-layer flow coming from upstream, Imai (Proc. 11th Intern. Congr. Appl. Mech. (Springer- Berlin- 1964) p. 663) proposed a new method of approximation to replace the convective velocity in the Navier-Stokes equations by the velocity of a uniform-shear flow. In the present paper, in order to simplify the analysis, the convective velocity is replaced by an adequate mean velocity of the uniform-shear flow in the boundary layer. The approximate solution for the flow near the trailing edge is obtained. The skin friction on the flat plate is calculated and proved to be accurate for high Reynolds numbers.

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The unsteady viscous flows past a semi-infinite flat plate are investigated on the basis of the Stokes approximation. Accelerated flows started from rest and oscillating flows are dealt with as typical examples.
For the initial period of acceleration and for high frequencies of oscillation the present analysis gives results valid throughout the flow field including the vicinity of the leading edge. The local shear stress is calculated at the leading edge region and the far downstream region.

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The forced convection flow of liquids past a heated flat plate with temperature-dependent viscosity and thermal conductivity is analysed. Velocity and temperature profiles as well as skin friction and heat transfer characteristics on the plate are obtained, by use of Kármán-Pohlhausen technique and the assumption that the viscous boundary layer is thicker than the thermal layer.

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Dynamics of a viscous, electrically charged, simple gas is studied. The Navier-Stokes equations for the charged gas are the basis of our analysis. The assumption that the gas is “incompressible” and isothermal simplifies the fundamental equation. As typical examples, the Rayleigh- and oscillating plate-problems are examined. The velocity distributions and the shear stresses on the plate for these flows are calculated.

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The effect of an aligned uniform magnetic field upon the stability of a two-dimensional jet is investigated for large values of the Reynolds number R.
The wave-number α and the phase velocity c_r of the neutral disturbance are obtained as functions of the Alfvén number A, the magnetic Prandtl number γ and R. The critical Alfvén number A_c is found to be 0.34 for infinite value of αR and it does not exceed this value even for finite values of αR.

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A combination of experimental and analytical methods is used to determine the velocity of fluid in a starting flow process in a circular tube. The developing pressure gradient, measured experimentally in the fully developed region, is expressed as a function of time and is used in the solution of Navier-Stockes equations for axial flow in a circular tube. Expressions for velocity in time and space and the average discharge are obtained by Laplace’s transformation technique. The velocity profiles and discharge under time-dependent pressure gradient are compared with those under constant pressure gradient. Significant differences between the velocities are found during the flow establishment, and the assumption of constant pressure gradient in the period of flow establishment, as considered in a number of studies, appears to be unsatisfactory.

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