Angular distributions of inelastically scattered alpha-particles, leading to the ΔT=0 spin-flip states of C¹² at 12.7 MeV and B¹¹ at 8.6 MeV, were observed. These angular distributions were found to show a unique pattern. Such characteristic of the angular distributions were also observed for the 10.4 MeV state of Mg²⁴ and the 8.9 MeV state of Si²⁸. These four states were systematically interpreted as the ΔT=0 spin-flip states by the j-j coupling shell model.
The excitation mechanism for these states is discussed and it is concluded that a spin-orbit interaction between the incident alpha-particle and a nucleon in the target nucleus plays an important role.
The angular distribution for another unnatural-parity state of C¹² at 11.8 MeV (2⁻), Mg²⁴ at 5.22 MeV(3⁺) and Si²⁸ at 6.27 (3⁺) were also observed.
The 14.08 MeV collective state of C¹² was found to be excited strongly.

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Wave functions, energy levels, transition moments, tunnelling coefficients, and chemical kinetic constants for a model of hydrogen bonding are obtained by solving numerically one dimensional Schrödinger equation. The proton tunnelling is possible for the hydrogen bond of appropriate distance between donor and acceptor 2.70∼2.95 Å. The proton behaves like a harmonic oscillator for shorter distance. The proton exchange in the course of the vibration will be unobservable for longer distance.

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The differential and integrated cross sections are calculated for the elastic scattering of a slow electron by the hydrogen molecule. The short-range electrostatic interaction is expanded in terms of the spherical harmonics and only the first two terms are taken into account. The long-range polarization and quadrupole interactions are also included. Most of the calculations contained in this paper are carried out, however, for the spherical potential alone. To a certain approximation, the non-spherical potential has been found to be negligible. The exchange effect is taken into consideration through an approximate attractive potential function, similar to Slater’s potential in the theory of atomic structure. Results of calculations agree fairly well with experimental data.

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An additive hereditary functional theory of viscoelastic deformation has been developed by simplifying the general Green-Rivlin theory by means of interpreting a series of rational experiments on bulk elastomers. Application to simple shear flow is discussed in detail.

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Microscopic observation of the domain structure in polycrystalline BaTiO₃ is carried out. After the specimen is cooled down to room temperature through the Curie point the domain structure changes gradually from an initial irregular one to a final one consisting of fine stripes of 90°-domains. Such a change is named “90°-splitting.” The aging of dielectric constant may be due to an increase in clamping effect by the 90°-splitting. This “90°-splitting model” may explain also the agings in dielectric loss and hysteresis loop. The dielectric constant decreases linearly with logarithm of aging time. It was shown theoretically that the displacement of a 90°-wall towards the mechanically most stable position is proportional to the logarithm of time in the case of whisker crystal. The “logarithmic time dependence” of dielectric constant in polycrystalline specimen may be explained as due to the 90°-splitting which progresses at a rate proportional to logarithm of time.

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The thermal conductivity of KH₂PO₄, KD₂PO₄ and KH₂AsO₄ single crystals was measured in the temperature range from 4.5 to 300°K. For all the samples critical changes of the thermal conductivity are found at the Curie temperatures. The conductivity decreases gradually with falling temperature in the paraelectric state where the phonon mean free paths are limited by the disordered hydrogen atoms to the lattice spacings. It rises steeply just below the Curie temperature, increases exponentially with further temperature fall and attains to a maximum near 10°K. A marked isotope effect is observed in the maximum values of KH₂PO₄ and KD₂PO₄. The former amounts to 600 mW/cm°K and the latter about 5500mW/cm°K. This effect may be attributed to the difference of hydrogen motions in the double-minimum potentials. The peak of KH₂AsO₄ is only 220mW/cm°K. A small anisotropy in the conduction is found in the exponential variation range for these three crystals.

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Fine particles of chromium were produced by evaporation and condensation of chromium in argon at low pressures (Kimoto et al.: Japan. J. appl. Phys. 2 (1963) 702). Electron diffraction studies have shown that the particles have the ordinary b.c.c structure of chromium when the argon contains a small amount of air or oxygen but they have a new structure when the argon is pure.
The new structure has a cubic primitive lattice with lattice constant a₀=4.588±0.001 Å. The unit cell contains eight chromium atoms; the probable space group is Pm3; one atom occupies position (a) 000, one atom occupies position (b) (Remark: Graphics omitted.) and the remaining six atoms distribute themselves so that on the average one-quarter of an atom occupies each of the 24-fold position (1) xyz; where (Remark: Graphics omitted.), y=v, (Remark: Graphics omitted.) with parameters u=0.2⁄100, v=4⁄100 and w=1⁄100. This is a disordered atomic arrangement derivable from the β-tungsten structure. The shortest Cr-Cr distance is 2.34 Å.
The new modification transforms into the ordinary b.c.c. form above 400°C.

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A semi-phenomenological theory is developed on the basis of some assumptions in order to study the singularities of thermodynamic quantities in the vicinity of the Curie point. First, microscopic expressions are found for the coefficients in the expansion of the thermodynamic potential in terms of cumulants. Cumulants of all order are calculated in the one-dimensional Ising model, and the series expansion of the fourth order cumulant is also obtained in the two-dimensional Ising model. The three-dimensional Heisenberg model is also discussed, using the result of Rushbrooke et al. In all cases, the fourth order coefficient in the expansion of the thermodynamic potential tends to zero at the Curie points. And, in the last case, the eighth order coefficient diverges at the Curie point.

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The thermoelectric powers of a series of palladium alloys with elements from the first transition series have been measured between room temperature and 500°C. The probable variation of density of states with composition in these alloys is considered, and the thermoelectric power results are assessed in terms of this variation. It is found that, although in some cases the thermoelectric power shows a striking composition dependence, there is no obvious correlation between thermoelectric power and density of states.

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The isochronal relaxation of internal friction and resistivity was investigated for Al+0.25 wt pct Fe samples deformed to 50% reduction in area. The results suggest that vacancies interact with solute atoms forming complex aggregates (Annealing Band I), which can dissociate when supplied with thermal activation originating relaxation Band II. At higher temperatures, Band III, the internal friction and resistivity changes seem to arise from strain fields around the precipitate particles in the overaged condition. Recovery of the deformed material occurs in Band I, while recrystallization in Band II.

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Several peaks of the photoconductivity near the band edge of the cadmium sulfide single crystals are studied. The peaks are due to the exciton and the shallow donors caused by the native defects. The correlation between the peaks and the defects due to the deviation from the stoichiometry of the crystals is investigated. At 300°K it is confirmed that P₁(507.5 mμ), P₃(517 mμ) and P₅(532 mμ) appear in the crystal containing sulfur vacancies and that P₂(513.5 mμ) and P₄(522.5 mμ) are remarkable in the crystal containing cadmium interstitials. The peaks of the exciton photoconductivity, i.e., A, B and C, were observed at 501.5 mμ, 498 mμ and 485.5 mμ at 300°K, respectively. The temperature shift of the band edge is estimated to be 3.00×10⁻⁴ eV/°K from the data of the exciton A, B and C and P₁. From the results, the possible electronic transitions are discussed.

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Effects of diffusion on energy transfer between molecules are considered by using two methods. One is the scattering length method, and the other is the Padé approximant with the diffusion constant as the expansion parameter. From these methods we obtain the decay function of the emission by excited molecules in a closed form of time t. The decay constant is expressed as a function of diffusion constant and is compared with the experimental results obtained by Tomura and Ishiguro.

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With regard to the properties of the A-center of additively colored KBr crystals, it is described how they are modified when the crystals contain divalent cations as impurities, besides a foreign alkali impurity associated with the A-center, Na⁺ or Li⁺ ion. Divalent impurities such as Ca⁺⁺ or Sr⁺⁺ enhance the growth of the A-center but deteriorate the thermal stability of this center.
On the other hand, the existence of these divalent cations does not affect A′-band. The activation energies for the formation and thermal destruction of the A-center are measured as being 0.26 eV and 1.0 eV, respectively, independent of the existence of divalent ions. The ionic conductivity is increased by 50∼70 times in the vicinity of room temperature by additively coloring a sample containing Ca⁺⁺ or Sr⁺⁺, and is less increased in case of Ba⁺⁺ or Cd⁺⁺.

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The martensite transformation of thin foils of Cu–Al alloy was studied to know the effect of specimen thickness on stacking fault probability in the martensite. Stacking fault probabilities were obtained from shifts of electron diffraction spots by applying the diffraction theory of crystal with stacking faults which has been developed by Kakinoki and Komura. Only one stacking fault parameter β was sufficient to describe stacking disorder in the present case. Obtained values of β cover almost all the range from 0 to 1, where β=1 corresponds to h.c.p. structure. Such large values of β including β=1 can not be obtained from the martensite transformation of bulk specimens. The effect of foil thickness on stacking fault probability was directly examined by making use of high transmissive power of 500 kV electron microscope, and it was found that the probability β increases with decreasing foil thickness.
It is inferred that the martensite transformed in thin foils has a strong tendency to approach to h.c.p. structure, a more stable one, by introducing stacking faults on (001) plane of the orthorhombic lattice.

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In order to study the plastic deformation behavior of b.c.c. metals in the region near the yield point, the successive stress relaxation method was developed. Results obtained with molybdenum polycrystals having two different yield strengths were analyzed to show that the true plastic strain rate can be expressed in terms of the product of two functions, one being dependent solely on the plastic strain while the other on the applied stress only, i.e., \dotε∝f(ε)g(σ). It turned out that those functions are in the form of f(ε)∝ε and g(σ)∝σ^m or exp(−D⁄σ), respectively. This appears to support the Johnston-Gilman concept for the region concerned, on which the contribution of mobile dislocations to yielding behavior was examined separately in terms of the mobility and the density. Various parameters characterizing dislocations are compared between the two kinds of samples.

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The emission spectra of the F center by irradiation into F, K, L₁, L₂ and L₃ bands have been observed in KCl, KBr and KI crystals additively colored. The peak positions and the half widths of the emission band by the L₁ light excitation were 1.21 eV, 0.26 eV; 0.96 eV, 0.21 eV; 0.88 eV, 0.14 eV in KCl, KBr and KI crystals, respectively, at liquid helium temperature, which were almost the same as those by the K or F light excitation. The ratio of the quantum yield of the emission by the L light to that by the F light, η_L⁄η_F, was between 0.44 and 0.83 in crystals examined. The emission intensity by the L band excitation dropped at temperatures above 100°K, 80°K and 60°K in KCl, KBr and KI crystals, respectively. This behavior of the emission intensity is similar fashion to that by the F light excitation. These results suggest that at low temperatures some of conduction electrons originating from either F or F′ centers by the stimulation into the L bands are captured at negative ion vacancies to form F^* centers. Then, F^* centers emit the ordinary F emission with the electronic transition to the ground state.

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The absorption, excitation, and emission spectra of the thallous ion centers in sodium iodide-thallium crystals were measured at 30°K, 77°K, and at room temperature. In particular, the nature of the double thallous ion center was investigated in comparison with the single thallous ion center. The double thallous ion center has two processes of exciting luminescence, 305 mμ absorption band leading 325 mμ emission band, and 310 mμ absorption leading 425 mμ emission. The 425 mμ emission band is also excited by the 291 mμ absorption band of the single thallous ion center. For two types of emission bands appearing at 425 mμ, their half-widths are different both in magnitude and temperature dependence. This suggests that they are induced either by single or double thallous ion center. The polarized luminescence from the crystal excited by a certain linearly polarized light was examined in order to consider the model of the double thallous ion center.

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De Haas-Shubnikov oscillations of the resistivity and Hall effect have been measured in antimony doped n-type germanium crystals which are in the state of metallic impurity conduction. The oscillatory behaviors can be explained qualitatively by an anisotropic multivalley band picture resembling to the conduction band. The period of the oscillations can be explained by assuming a little different mass parameters from those for the conduction band.

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Exciton states in alkali halides are analyzed on the basis of the energy band picture. First the excitons at the point Γ are discussed. A simple treatment in which the spin-orbit and the electron-hole exchange interactions are taken into account indicates that the intensity ratio of the halogen doublet is fairly sensitive to the exchange energy, while the doublet splitting is not very sensitive. It is shown that a pure triplet exciton state exists below the first allowed exciton state. Although such a state has not yet been detected, lifetime broadening of the first peak due to the existence of such a hidden state is conceived to make the magnitude of the width of the first peak comparable with that of the second peak.
The pronounced structure observed in K and Rb halides in the spectral region just above the step is ascribed to dε exciton formed at the point X. Multiplicities of the observed absorption peaks are explained in terms of this model. Semiquantitative analysis of the triplet structure in KBr and RbBr is made.

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Transient Photoconductivity of additively colored KCl is studied for excitation in the F, K, L₁ and L₂ bands at low temperatures down to 1.3°K. Electron quantum yield is found near unity in L bands and in high energy tail of K band in the whole temperature range. K band can be divided into two components; K₁ band with low electron yield and K₂ band with unit yield. It is concluded K₂ band corresponds to transition to the conduction band minimum and L bands to the states in the conduction band. Electron yield for K₁ and F bands is studied as a function of temperature and applied electric field. Thermal binding energy of excited state is found the same for K₁ and F states. Field ionization from K₁ state starts at far lower field than from F state. Transport of electrons at low temperature is characterized by non-ohmic behavior above critical field, where electron Schubweg is proportional to E^0.5∼0.7. The high field behavior can be understood as hot electron phenomena.

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The impurity conduction in phosphorus doped n-type silicon has been investigated at temperatures between 1.1°K and 300°K. The samples ranged in concentration of excess donors from 1.2.10¹⁸ to 2.5.10²⁰cm⁻³. A metallic type impurity conduction and a negative magnetoresistance are observed in samples containing higher than 4.10¹⁸cm⁻³ excess donors. An intermediate type impurity conduction is observed in samples containing from 1.7.10¹⁸ to 4.10¹⁸cm⁻³ excess donors. In metallic samples with donor concentration higher than 6.10¹⁸cm⁻³, the resistivity increases monotonically with temperature T up to the Fermi degeneracy temperature T_D of respective samples according to a simple formula, ρ(T)=ρ(4.2°K)[1+A(T⁄T_D)^B], where A and B are constants.

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The experimental study of residual resistivity and magnetic susceptibility of dilute alloys of nickel in liquid bismuth is presented. The increase in resistivity by the addition of one atomic percent nickel amounts to 0.45 μΩ cm. The localized electrons of nickel are non-magnetic in liquid bismuth and the increase in the susceptibility by d-state of additional one percent nickel is 0.2×10⁻⁶ C. G. S. e. m. u.
It is concluded that the density of the virtual bound state of nickel in liquid bismuth is not so large compared with that of the conduction electron.

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A study is made on the preparation and the magnetic properties of the polycrystal film of MnSb. Magnetic properties and crystal structure of the film are investigated through ferromagnetic resonance and electron diffraction, respectively. The Curie temperature T_c for the MnSb film is determined from the anomaly in the temperature dependence of electrical resistance. The films are deposited onto glass substrates. Their thicknesses are estimated to be between 300 and 4000 Å. The MnSb film is able to be obtained by melt-evaporation when the filament temperature T_f is higher than 1500°C and by flash-evaporation when T_f≥1250°C. The MnSb film has a=4.13 Å, c=5.79 Å, c⁄a=1.40 and T_c=310°C. The observation of spin wave resonance is possible only in the MnSb film deposited on an unheated substrate. The exchange coupling constant A and the exchange integral J for MnSb are determined to be A=0.30×10⁻⁶ erg/cm and J=7.0×10⁻¹⁵ erg. A relation between A and J is calculated on the basis of the atomic model for the polycrystal MnSb with a hexagonal NiAs type of structure.

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A ferromagnetic resonance spectrometer which enable the measurement for a film evaporated in ultra-high vacuum (UHV) prior to the exposure to air has been constructed. Nickel films made in UHV have much less magnetic perpendicular anisotropy field H_k (which is in the equation for resonance condition ω⁄γ=H_⊥−4πM+H_k in the perpendicular direction of the applied field to the film plane, where H_⊥ is the observed resonance field), about 3∼5×10² Oe, than those made in conventional vacuum by a factor of 6∼10. The absorption of residual gases causes H_k to become larger. Study on double-layer films, composed of two nickel films with an absorbed gas layer at their interface, results the different perpendicular anisotropy fields for each nickel film, one, in contact with the glass substrate, with smaller H_k than the other, besides the aging in UHV makes values shift in the contrary way for each film, like approaching to each other. Some qualitative explanations are given.

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The measurements of the magnetic susceptibilities have been made in the temperature range of 1.5°K∼300°K for three KMg_1−xCo_xF₃ single crystals with x=0.025, 0.050, and 0.110. The temperature dependence of the magnetic susceptibilities at high temperatures can be explained from the Pryce’s formula for a single Co²⁺ in an octahedral field. The deviations from the Pryce’s formula are found at low temperatures. These deviations can be explained by the effect of the exchange interactions between the neighboring Co²⁺ in the crystals. By assuming that the Co²⁺ ions are randomly distributed in the Mg²⁺ site, the contributions from the various types of isolated clusters to the total susceptibility are calculated. The observed susceptibilities can be fitted to the calculated values, if the exchange interaction is taken as −J(s_i·s_j) with J equal to −70±10cm⁻¹, where s is the fictitious spin, 1/2, of the ground state of a single Co²⁺ in an octahedral field.

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The effects of the 1 % local magnetic field asymmetry on the confinement of a low \dotB(≅10⁸ Gauss/sec) theta pinch plasma were studied by means of high-speed photograph.
The plasma drifts radially toward the region where the strength of the magnetic field is minimum.
The mean drift velocity is several ×10⁵ cm/sec.
It decreases appreciably as the field strength at the instant of the crowbar loweres less than 0.5 of the maximum in a half-cycle.
The outward acceleration in the early stage was found to be
(Remark: Graphics omitted.)
by the magnetohydrodynamic model where b⁄B₀ is the degree of the field asymmetry and a is the radius of the plasma column.
The dependences of the observed drift velocity on the time of the crowbar and on the initial pressure are explained according to the above formula.
The 1 % local field asymmetry gives a serious limitation On containment of a high-temperature plasma.

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The electric current-diffusion layer near the current sheet in a magnetic shock tube is analysed by extending Falk and Turcotte’s method to the case in which the driving magnetic field varies with time. Some numerical results for the temperature, velocity, density, pressure and magnetic field are presented in terms of similarity variable when the driving magnetic field varies as a power of time. The results show that the back end of the flowing gas is displaced from its infinite conductivity position by introducing the thermal and electrical conductivities, and the temperature at the back end of the gas becomes finite, the value of which depends on the ratio of thermal to electrical diffusion parameter specified by ν.

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Observation is made of the shape of small drops (or bubbles) moving through viscous liquids with a constant speed. Main concern is to investigate how the deviation of the drop shape from a sphere depends on the physical quantities of fluids, the drop size and the drop velocity. It is shown that the deformation is governed mainly by the Weber number, the dimensionless quantity including the interfacial tension, as Taylor and Acrivos pointed out from the theoretical point of view. Also it is shown that their formula for the drop deformation is not valid if the ratio of Weber number to Reynolds number becomes larger than about 0.4.

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Theoretical studies are made of the harmonic generation in a high frequency gaseous plasma under an external magnetic field on the basis of the Boltzmann equation. Expressions for the intensity of the higher harmonic radiations, especially of the second and the third, are derived and the results of their numerical calculation are graphically presented. These show that the higher harmonic radiations have sharp resonance peaks. The theory is compared with the experiment by Hill and Tetenbaum.

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The effects of magnetic field, pressure and discharge current on the saturation electron current flowing in a cylindrical probe are investigated by use of two methods: one is based on the probe characteristic of ion current and the other on the microwave measurement. Experiments are made in helium at pressures ranging from 0.3 to 1.6 mmHg with 10¹¹∼10¹² cm⁻³ of plasma electron density and 0∼5000 gauss of magnetic field strength. Results of experiments show that the thickness of sink region around the probe perpendicular to the magnetic field is given by V_e⁄(ω_p²+ω_B²)^1⁄2 where V_e is the thermal velocity of electron, and ω_p and ω_B are the angular frequencies of electron plasma and cyclotron, respectively. Use of this region and the theory developed by Dote enables us to determine the numerical value of the electron density of magneto-plasma. The result obtained by using electron current characteristic of the probe with its axis parallel to the magnetic flux agrees well with the real density. The measurement on the probe perpendicular to the magnetic lines of force is also carried out.

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