A second-order DWBA analysis is made on the ⁹⁴Mo(p, t)⁹²Mo reaction data at E_p=31 MeV. The anomalous angular distribution of the 3₁⁻ state (Ex=2.84 MeV), which can not be explained by the single-step excitation mechanism, is found to be well accounted for in terms of the two-step processes via target and residual core excitations.

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The B8_2–D8_8 phase transition is considered as the simultaneous creation and anihilation of long range orders of vacancies and strain.
Both order parameters of vacancies and strain are expressed by the Ising model, and the free energy of the system is calculated by using the method of symmetry breaking potentials in the high temperature region.
Temperature dependence of the free energy shows that the B8_2–D8_8 phase transition is of second order.
The critical temperatures are expressed as a function of the ratio of pairing energies of atom-atom, vacancy-displacement and displacement-displacement.

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It is clearly shown that summation of divergent diagrams yields a logarithmic term in the density expansion of transport coefficients. The logarithmic term is explicitly given in a simple and general form for an electron impurity system. Long time behavior of a non-Markoffian collision operator appearing in the generalized Boltzmann equation is also investigated.

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In order to solve the questions (i) why, (ii) when, and (iii) how strongly the overshoot exhibited by the nonsteady nucleation process occurs, a one-dimensional system of Brownian particles in a constant external field is discussed first. Then by analogy of this, the overshoot in the nonsteady nucleation is shown to occur (i) as the result of the time-lag between the diffusion current and the drift current, and of their balancing at the final stage, (ii) at a time t_max proportional to g^α (2\gtrsimα>1) in terms of the cluster size g, and (iii) it amounts to the value of the diffusion current at the steady state which is balanced with the drift current.

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Shifts of the magnetic transition temperatures of MnP, T_c(=290.5 K), the Curie temperature, and T_α(=47 K), the transition temperature from the screw spin state to the ferromagnetic state, are measured in the presence of uniaxial pressure. Strains due to uniaxial pressure are measured in the vicinity of T_c, and strains in the vicinity of T_α are estimated from the sound velocity. From these data, the strain dependence of T_c are obtained as ∂T_c⁄∂e_a=(4.49±0.32)×10³ K, ∂T_c⁄∂e_b=(−1.05±0.25)×10³ K, and ∂T_c⁄∂e_c=(4.56±0.28)×10³ K, and the strain dependence of T_α are estimated as ∂T_α⁄∂e_a=−3.02×10³ K, ∂T_α∂e_b=16.5×10³ K, and ∂T_α⁄∂e_c=−2.11×10³ K. The interatomic-distance dependence of the exchange interactions in MnP is discussed.

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Magnetization process is analysed in an antiferromagnetic Ising Dy³⁺ spin system of DyCrO₃. The existence of magnetic Cr³⁺ ion plays an important role in the stepwise magnetization process of DyCrO₃, compared with the one-step magnetization process of DyAlO₃ which has no magnetic transition-metal ion. The indirect interaction between Dy³⁺ spins induced through the Cr³⁺–Dy³⁺ exchange interaction, together with the superexchange interaction between Dy³⁺ spins, possibly makes the magnetization change stepwise. A future measurement of the magnetoelectric effect would determine the proposed spin-configuration in the intermediate field range.

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The thermal conductivity of a quasi one-dimensional antiferromagnet KCuF₃ has been measured. A large enhanced conductivity in the direction of a linear magnetic chain is observed above T_N. The results of analysis based on Huber’s theoretical prediction and the dynamical scaling hypothesis indicate that the behavior of the enhanced conductivity can be understood as an energy diffusion in the linear magnetic chain.

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Magnetic phase diagrams for alloys Tb–Er, Dy–Er, and Ho–Er are studied on the assumption of anisotropy energies of the form of DJ_z², with opposite signs of D for the two components, and exchange interactions among spins of different magnitudes for the two components. Molecular field appoximation is made. Neutron diffraction results are well explained, particularly with respect to the hitherto unexplained transition helix to elliptic oscillation which occurs in a certain concentration range as temperature goes down. Effect of higher order anisotropy energies is discussed and is shown to be unimportant except at low temperatures.

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The ratio of the gradient-elastic tensor, S₁₂⁄S₂₂, has been measured at the ²³Na sites in a ferroelectric NaNO₂ crystal at room temperature by the method of a nuclear magnetic resonance saturation due to the acoustic excitation. The obtained ratio is compared with a calculation based on the point charge model and another calculation in view of the contribution from the higher multipole moments of the NO₂⁻ ion (the point multipole model). The experimental value can be explained reasonably with the point multipole model rather than the point charge model.

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Spectral changes of the exciton absorption lines in YCrO₃ observed during the field-induced spin reorientation are studied on the basis of the method of an effective Hamiltonian. The effective Hamiltonian expanded in powers of a magnetic field is made invariant to the symmetry operations of the magnetic group to which the spin arrangement during the spin reorientation belongs. The values of the parameters in the effective Hamiltonian are determined so as to fit the observed line shifts. The relative intensities of the exciton lines calculated by using these values of parameters are in a good agreement with experiments. By expressing the absolute values of the energy-transfer matrix elements in various Cr³⁺-pairs in terms of these parameters, the magnetic-field dependences of these matrix elements are obtained and their physical implication is discussed.

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A manageable expression for calculating the total energy of a solid is given in the Hartree-Fock approximation when one-electron wave functions are given by the APW method. The lattice sum in the expression is written down exactly, with the use of the structure constants in the KKR method.
The total energy of metallic beryllium is computed from the APW functions obtained from the band structure calculation, in which the shape of the Fermi surfaces was in good agreement with the experiments. The result is quite favorable, as an approximation which neglects the correlation energy. We find that the cohesive energy of beryllium comes mainly from the difference in the Hartree-Fock energy in the atom and the solid. The exchange operator in real solid is found to depend on the wave number very slightly. The exceptionally high cohesive energy of beryllium is closely correlated with the formation of the bonding charge reported previously.

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The thermoelectric power of a binary alloy with off-diagonal disorder as well as diagonal one is calculated by means of the extended coherent potential approximation due to Shiba and others. It is shown that the off-diagonal disorder has a very striking effect on the thermoelectric power as well as on the conductivity. In the calculation the “underturbed” band is treated accurately for a simple cubic tight-binding model. Our improved treatment of the van Hove singularities of the “unperturbed” band reveals that the effect of the singularities on the transport coefficient is more pronounced than that calculated by Levin et al.

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The Landau level broadening of the electrons in antimony has been investigated by ultrasonic attenuation measurements under the conditions q⁄⁄H⁄⁄ a bisectrix axis, ν=60 MHz (quasi-longitudinal waves), 1.15 K<T<1.90 K and H<120 kG. From the Shubnikov-de Haas type oscillations in 3.5 kG\lesssimH\lesssim7 kG for an annealed sample, an effective Dingle temperature T_D=0.42 K is obtained for the electrons, while from the giant quantum attenuation in high fields up to 120 kG an effective temperature of the level broadening, T_g=0.0027 K, is obtained for the same extremal orbit of the electrons and for the same sample. It is shown that T_D is sensitive to whether samples were heat-treated or not, but T_g is rather insensitive. The origin of the extraordinarily large difference between T_D and T_g is discussed in some detail.

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Domain patterns in Au₃Cu have been investigated by means of transmission electron microscopy. Samples were quenched from 800°C and subsequently annealed at temperatures between 100°C and 165°C for various periods of time. The electron microscopic observations are correlated with measurements of the electrical resistivity.

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Foil specimens prepared from bulk ones which were prestrained about 10⁻¹ in shear strain have been reversely loaded directly inside a 3MV-class electron microscope and associated behaviors of individual dislocations have been continuously observed.
With increasing reverse stress from 0 to the prestress level, dislocation-structures such as widely spaced primary dislocations, dislocation pile-ups and Taylor type dislocation-dipoles decompose in sequence according to their mechanical stability. The highly stabilized dislocation-structures such as Taylor type dislocation-dipoles on closely spaced slip planes and heavily tangled dislocation-groups combined with different slip systems are retained even under the reverse stress higher than the prestress level.

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Movement of dislocations induced by unloading and reverse stressing have been directly observed in copper by the in-situ observation technique with a 3MV-class electron microscope.
By unloading, isolated dislocations in the interior of cells make backward movements after inverted their bowing direction.
When the stress is applied in the reverse direction, these isolated dislocations are swept away from the interior of cells, and dislocations in cell walls begin to move. In this case, both position and dislocation density of cell walls are scarcely changed during deformation until the reverse stress reaches the prestress level. In the stress range higher than the prestress level, the cell structure is developed around these pre-existing cell walls in the same way as in the case of forward deformation. These results are discussed in terms of the nature of cell walls.

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Volume-plasmon damping in In, Cd and graphite have been studied by measuring the angular dependences of the energy, the half-width and the intensity of the plasmon peaks. The angular dependence of the half-width was analyzed in the form of Γ_p=A+Bθ². As a result, it was confirmed for these elements that there were two groups in relation to the behavior of the plasmon damping as reported in our previous paper, that is, In, Cd and π-plasmon of graphite belonged to the first group in which A had relatively small values and B was positive, and π+σ-plasmon of graphite belonged to the second group in which A had relatively large value and B was negative. The plasmon energies and the dispersion coefficients were also given.

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Thermal conductivity measurements on single crystal niobium specimens of resistivity ratios 6300 and 2500 are reported as a function of magnetic fields. The measured thermal conductivity varies linearly with H_c2−H in fields very close to H_c2 and approximately with (H_c2−H)^1⁄2 in slightly lower fields, as predicted by the Houghton-Maki (HM) theory. Experimental results on Nb6300 in longitudinal fields agree with the HM theory using the density of states N(0)=2.3×10³⁶ cm⁻³ erg⁻¹ at lower temperatures (T\lesssim3 K) whereas at higher temperatures (T\gtrsim4 K) they do not agree with the theory. Experimental data on Nb6300 in transverse fields cannot be explained by the theory with the same N(0) as in the longitudinal case, even at low temperatures. The field coefficients of the thermal conductivity do not show the purity dependence in our specimens investigated.

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The dielectric constants and the dc resistivities of Ag-rich alloys, AgTi, AgV, AgCr, AgMn, AgFe, AgCo, and AgNi are measured at room temperature and in the range of solute concentration, 0.2 to 15 at%. The samples are prepared by simultaneous deposition method. The dependence of the impurity resistivity on the solute metals is in qualitative agreement with the results for Au- and Cu-matrix. The collision frequency, and the ratio of the density of conduction electrons to the optical effective mass vary with solute metals in the similar way to the impurity resistivity. The distribution of the density of the virtual bound states is given. The result is discussed on the basis of the Anderson model.

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Five single crystals with nearly same composition but different vacancy concentration between −0.005 and +0.035 in formular unit are grown by the Bridgman method. Resistivity in the frequency range between 100 Hz and 100 MHz and Seebeck coefficient are measured in temperatures ranging from 78 to 300 K. The electrically obtained concentration of Fe²⁺ ions is in good agreement with that obtained by chemical analysis. The activation energy of an electron bound to a Fe²⁺ ion on B sites is of the order of 10⁻² eV and increases with increasing vacancy concentration. The polaron binding energy is of the same order as the electron binding energy, and corresponds to that of small-polaron conductors. This energy is independent of cation vacancy concentration between 4.7×10²⁰ and 11×10²⁰ per unit volume but decreases 13% with the formation of anion vacancy concentration of 1.1×10²⁰.

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Galvanomagnetic properties in n-InAs are studied at 77 K by means of the Hall measurement technique. The electron mobility at the low electric field is controlled by ionized impurity scattering and quantum effects. In the intermediate electric field, the electron mobility shows an E^−1⁄2 dependence and it is determined by acoustic phonon scattering. Experimental results of the electron drift velocity are in good agreement with the numerical analysis given by Curby and Ferry in the electric field where the carrier density is almost constant (E\lesssim1000 V/cm). At the high electric field and transverse high magnetic field in the avalanche breakdown region, the drift velocity is observed to saturate which might be due to optical phonon scattering. In this region the saturation velocity υ_s decreases with increasing the transverse magnetic field B and the experimental relation υ_s∝B^1⁄3 is obtained.

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The principal coordinate systems of electric field gradient (EFG) at deuteron sites in hydrogen bonds are obtained at −120°C by means of Volkoff method. The shift in angle of 10 degrees is found in the orientation of the principal z axis of EFG at two of four inequivalent sites, and about 3 degrees at the other two sites. These shifts are attributable to the rotational displacement of SO₄ ions. The temperature dependence of the resonance line separation is measured in the ferroelectric phase with the magnetic field parallel to the crystalline a axis. It is found that this temperature dependence, that is, the temperature dependence of EFG is proportional to the spontaneous polarization obtained in the present study by the pyroelectric method. In the limited temperature range, from −30 to −100°C, the separation of resonance lines and the spontaneous polarization depend on temperature as (T_c−T)^β, with β of 0.33.

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The energy relaxation process in n-type InSb at liquid helium temperatures under the presence of strong longitudinal magnetic fields has been analysed taking into account the existence of an impurity band. The impurity band is found to act as a thermal reservoir of the conduction band electrons, which strongly affects the energy relaxation process. The observed saturation in the magnetic field dependence of the energy relaxation time is ascribed to the reduction of the rate of energy dissipation of conduction band electrons to the lattice, which arises from the interaction between electrons in the conduction and the impurity band.

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The piezo-modulated reflection spectra of the first peak of TlBr have been measured at LNT using bending mode resonance to investigate the stress response and to locate the critical point in the Brillouin zone where the transition occurs. They have been analysed with the aid of the wavelength modulation spectra measured simultaneously with the piezo-spectra. The piezo-optical responses for [001], [111] and [110] stresses are well described in terms of three symmetry-adapted response functions: W₁(E) and W₃(E), with W₅(E) being zero. The first peak is attributed to the transition at the X point in agreement with the band calculations. The tetragonal deformation potential is estimated to be about 0.9 eV. The behavior of the W₃ spectrum is interpreted well by taking into account the intra- and intervalley interactions of direct exciton states at different X points.

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The phase diagram of (NH₄)₂SO₄–K₂SO₄ mixed crystal system was obtained from dielectric and pyroelectric study. It was found that the ferroelectric phase transition temperature T_c decreases with the increase of concentration of K⁺ ions, and ferroelectric phase disappears if mixed crystals contain more than 70% of K₂SO₄. It was also found that the spontaneous polarization of mixed crystals with low concentration of K⁺ ion (up to 30%) increases first to maximum, and then gradually decreases as the temperature is lowered. These experimental observations suggest that in this system single homogeneous polarization may not be an order parameter and the dipole arrangements of this system may be not ferroelectric but ferrielectric as was first pointed out by Unruh.

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The specific heat of CaCu(CH₃COO)₄·6H₂O has been measured between 0.3 and 8 K. The present result showed the Schottky anomaly, which was analyzed to be due to the hindered rotation of CH₃ groups. The validity of present hypothesis was evidenced by the specific heat measurements of the deuterated sample CaCu(CD₃COO)₄·6H₂O between 0.25 and 1.0 K. From the specific heat measurements, energy splitting ΔE⁄k_B is estimated as 2.57±0.02 K for CaCu(CH₃COO)₄·6H₂O and 0.24±0.03 K for CaCu(CD₃COO)₄·6H₂O.

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Photon-induced dichroism and its isothermal decay of γ-irradiated CdCl₂:AgCl are investigated in the range of 1.8–25 K. Conventional measurements of anisotropic absorption spectra reveal that at least two bands peaking at 395 and 540 nm are attributed to Ag²⁺ centers distorted tetragonally by the Jahn-Teller effect. Time-dependent detections and analysis of the dichroism under excitation with polarized light allow to determine the ratio f(≡σ_⊥⁄σ_⁄⁄) of dipole strengths parallel and perpendicular to the distortion axis, yielding f\simeq5.9±0.5 and 7.1±0.5 for the 395 and 540 nm bands, respectively. The rate of thermal reorientation of the distortions among three equivalent configurations is found to be expressed by w(T)=ν₀exp(−E⁄kT) with the values E\simeq250 cm⁻¹ and ν₀\simeq2×10⁵ sec⁻¹.

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The uniform susceptibility in a sinusoidally antiferroelectric substance, NaNO₂, has been measured over a wide temperature range up to the melting point. A clear deviation from molecular field nature has been observed above the Néel temperature, T_N. The deviation has been examined whether or not it is caused by any unessential reason, for instance the contribution of the thermal expansion of the lattice constants which is possible to give rise to a part of the deviation. As a result of the examination, it has been made clear that the deviation is of attribute in the temperature dependence of the susceptibility of NaNO₂. By applying a critical exponent expression, the data obtained above T_N have been analysed as follows,
1⁄χ(0)=(2.3±0.2)[ε^1.24±0.03+(1.4±0.15)×10⁻³],
where χ(0) is the uniform susceptibility and ε is (T−T_N)⁄T_N.

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Phonon dispersion curves along the principal symmetry directions as well as the Debye temperature versus temperature curves of nickel, palladium and platinum have been calculated on the basis of modified Bhatia’s model. Computed results are in good agreement with the experimental observations. The calculated distribution function g(ν) versus frequency ν curve of nickel is also compared with the experimental results.

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The temporal variation of current in polar dielectrics such as acetone, nitrobenzene, n-propyl, isobutyl and isoamyl alcohol shows that initially the current falls very rapidly and then slowly and finally approaches a saturation value. Assuming the existence of free ions in the liquid the quantitative theory advanced by Gemant has been further developed. The theory explains very satisfactorily the observed variation of current with time and enables us in conjunction with experimental results to calculate the mobility and charge density of the ions. The mobility is of the same order of magnitude as that of weak electrolytes and the ion density is found to be of the order of 10¹⁵ to 10¹⁶ ions/cc in agreement with the results obtained earlier.

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The Debye-Waller factors for nickel, aluminium and sodium are calculated at different temperatures using the anisotropic continuum dispersive model proposed by Sharma and Joshi for the lattice dynamics of metals. The theoretical results are compared with the existing experimental data in terms of the Debye-waller factor temperature parameter Y=loge₁₀(λ⁄sinθ)² (2W_T0−2W_T), where 2W_T is the exponent of the Debye-Waller factor at temperature T. The agreement between the theoretical results and the experimental values has been found reasonably satisfactory.

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A model for explaining the photoisomerization of the chromophore in rhodopsin molecule with a high quantum yield is proposed on the basis of the strain effect. Necessary conditions assumed in the model are shown to be satisfied by the calculation using a self-consistent HMO theory which is recently developed by one of the authors. It is also shown that when a double-bond is twisted by about 40°, a steep change occurs in the molecular geometry, and that calculated adiabatic potentials, absorption wavelengths and transition dipole moments show some anomalies, corresponding to the change. Calculated energy barriers for isomerization around single-bonds of Schiff-bases of retinal in the ground state are very small.

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The ²P_1⁄2→²P_3⁄2 excitation cross section of C⁺ in low energy collision with He is calculated with the close-coupling method. A pseudo-potential is used to calculate the repulsive interaction due to the electron cloud overlap between the colliding atoms. In low-energy region the cross section shows oscillatory structures which come from a shape resonance caused by the centrifugal barrier. The magnitude of the excitation cross section is a few times smaller than that for the C⁺–H collision. An estimate of the cross section of the same excitation in C⁺–H₂ collision is also given.

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The electronic structure of two systems, the hydrogen atom plus a quark, and the hydrogen negative ion plus a quark, is calculated by means of the molecular orbital method and the one centre expansion method. Quark affinities to H and H⁻ are obtained. It is concluded that the one centre expansion method is a suitable means of dealing with quark-containing systems.

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The effect of space potential on rf plugging of ion loss is studied experimentally: The ambipolar field produced by the difference of the plugging efficiencies between electrons and ions acts to reduce the electron loss and to increase the ion loss. The potential produced by the rf field and the space potential can be therefore determined from the measurements of ion and electron losses. The potential thus determined agrees with the theoretical predictions based on the collective behavior of a plasma.

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Kink instabilities in high β regime of tokamak, i.e. β_p∼ε^−1⁄2 and q(a)∼1, are studied in toroidal geometry, where ε is an inverse aspect ratio and q(a) is a safty factor at a plasma surface r=a. The n=1 kink mode becomes unstable for q(a) above Kruskal Shafranov limit. At marginal stability, the amplitude of m=2 mode becomes larger than that of m=1 mode for larger b⁄a, where b is a position of conducting shell. The stabilizing effect of conducting shell on the n=1 kink mode can be expected for b⁄a<1.4.

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Three-fluid nonequilibrium equations governing the flows of a partially ionized argon plasma are formulated. The equations are applied to the ionization-recombination nonequilibrium flow behind a strong normal shock wave, and to that in a convergent-divergent nozzle. The main consideration is made on the equipartition of the atom and ion thermal energies. For the flow behind a shock wave T_a=T_i is confirmed for a wide range of the upstream pressure. For the flow in a nozzle, T_a=T_i is usually confirmed. However, an example is shown in which T_i is in slight excess of T_a in the far downstream region from the throat.

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This paper deals theoretically with a slow flow of a grey radiating gas along an infinite flat plate. The plate is semitransparent on which a sinusoidal temperature distribution is given and through which an external radiation beam is imposed normally. The case is considered that the variation of the temperature is small, so that the analysis is based on the linearized equations. Asymptotic behaviours for optically thick gas are investigated making use of matched asymptotic expansions up to the second approximation correct to the order of the inverse of the Bouguer number. It is shown that the non-uniform temperature distribution may be confined only to a thin layer, whose thickness is of order of the photon mean free path, adjacent to the plate, when the plate temperature is suitably chosen. By this temperature distribution, a secondary flow is induced even in the region outside the layer.

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Low Reynolds number flow of an incompressible fluid past a body is studied by solving the Navier-Stokes equations, on the basis of the method of matched asymptotic expansions. It is shown that, when the shape of the body is symmetric with respect to a point, the force on the body is determined to the order of R_e²logR_e, where R_e denotes the Reynolds number, simply from a knowledge of the force on the body according to Stokes’ approximation.

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A steady axisymmetric source-sink flow of an incompressible viscous fluid in a rotating circular cylinder is studied. The source-sink distribution is idealized as the line distribution along the concentric circles on the top and the bottom. The effect of the discontinuity of the angular velocity across the same circles is also examined. The method of analysis is the boundary layer analysis of the linearized basic equations. The attention is concentrated on the details of the flow structure in the shear layers, and several numberical results are shown.

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The theory of nonlinear pulse waves due to nonlinearity of vascular walls is established. The blood is supposed to behave as an incompressible and homogeneous fluid obeying the Navier-Stokes equation, while the blood vessel is assumed to be a long axisymmetric tube whose mechanical properties are prescribed experimentally. The problem of the modulation of pressure waves is investigated.

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Finite-difference solutions of the Navier-Stokes equations are given in stream function-vorticity formulation for a series of Reynolds numbers and for varied positions of the cylinder in the channel. For flows in a doubly connected region, the value of the stream function on the body cannot always be given in advance. A new iteration scheme to solve such a problem is proposed for getting the proper solution by imposing a condition that the pressure is single-valued. The force and the moment of force acting on the cylinder are computed and their dependence on the Reynolds number as well as on the position of the cylinder is studied. The numerical errors caused by the existence of corners on the boundary are checked for Stokes flow by comparison with exact solutions, and their dependence on the mesh length is shown numerically.

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Motion of a vortex filament with a narrow core in an inviscid and incompressible fluid otherwise at rest is investigated numerically. Two types of initial conditions, a sinusoidal form with a single Fourier component and that of a superposition of the first and the third components, are assumed. In both cases, interaction between different components occurs owing to the nonlinear property of the governing equation, but the filament does not show random behavior and after a certain time it recurs nearly to the initial state. Analytical treatment is made and the numerical results are confirmed. Next, the case where an external flow field with an axisymmetric potential flow exists is examined, and an onset of randomness is observed. This is considered as due to a computational error amplified through the interaction between the filament and the external flow.

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