The relative intensities of internal conversion electrons of 240, 294 and 350 KeV γ-rays of RaB and ratios of those for K and L energy levels, α_K/α_L, have been investigated with a magnetic spectrometer of fair resolution and G-M counter technique.
Values of α_K obtained are in accord with the results of Ellis and Aston but those of α_L and α_M are slightly different from their values. The agreement between observed and theoretical values of α_K/α_L is satisfactory within the experimental error.

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The Lennard-Jones model of molecules of spherical symmetry has been generalized to non-spherical models without sacrificing analytical integrability of the second virial coefficient. The essential generalization consists in the definition of the intermolecular distance, ρ, the intermolecular potential, U, being supposed to be a function of ρ only and
U(ρ)=U₀\left[\fracmn−m\left(\fracρ₀ρ\ ight)ⁿ−\fracnn−m\left(\fracρ₀ρ\ ight)^m\ ight], n>m>3.
As the simplest extension ρ is defined by the shortest distance between molecule cores, as which thin rods (disks) are adopted in case of prolonged (flat) molecules. Next, ρ is so defined that the model becomes an attracting spheroid. For thèse models the second virial coefficient has been integrated analytically and tabulated. The model Constants have been determined for H₂, N₂, C₂H₄ and CO₂.

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La viscosité intrinsèque depend sérieusement au rapport σ de gradient de vittesse à constante de diffusion rotatoire de particule. La théorie de Kuhn, Eisenschitz et autres et celle de Simha concernant l’effet de mouvement brownien à la viscosité sont critiquées et une théorie nouvelle est donnée. La principe fondamentale est que la dissipation d’énergie doit être calculée par le travail fait par la force extérieure contre le courant de densité de probabilité qui contient le courant de diffusion. Computations sont faites pour ellipsoides de révolution. Viscosités intrinsèques décroissent monotoniquement avec croissement de σ. Au cas où le mouvement brownien est suffisamment efficace, les résultats finals sont identiques à ceux de Simha.

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La théorie de l’article précédent est appliquée aux macromolécules en chaîne. Computations sont faites pour les pelotes rigides complètement perméables pour le solvent traitées auparavant par l’auteur, et les molécules filiformes rigides allongées d’après le modèle de Riseman et Kirkwood. Les résultats resemblent à ceux d’ellipsoïdes de révolution.

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The angular distribution of the intensity of light scattered by macromolecules in solution has been calculated numerically, assuming these molecules as ellipsoids of revolution and cylinders whose dielectric constant is slightly different from that of the solvent. The results are given in graphs and they will be useful for the determination of the shapes of large protein molecules such as vaccinia virus.

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By using the quasi-crystalline model, the grand partition function of a binary solution, in which the molecular fractions are considered to be functions of the distance from the surface, is constructed. And the concentration is determined so as to make the system be in thermodynamical equilibrium. The surface tension and the surface excess amounts of components obtained in such a manner does not conflict with the Gibbs adsorption formula. Guggenheim’s theory of the surface tension of regular solution, based on the monolayer model, is a special case of the present theory. The monolayer theory, however, is in contradiction with the Gibbs formula, since the system cannot reach equilibrium state if the, difference of composition from the bulk phase is confined to such a thin region as mono-or twc-molecular layer.

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Molecules in certain normal long chain solid hydrocarbons or alcohols are well known to rotate around their long axis in high temperature phase. A simple statistical theory of rotational transformation similar to Bethe’s theory of order-disorder transformation in alloys is attempted, assuming that molecules librate, around their equilibrium position and sometimes change their orientation by thermal agitation. A sharp anomaly in observed specific heat is explained as the result of the cooperative transformation from ordered to disordered state in molecular orientation. The large value for the observed heat of transformation is attributed to the internal degrees of freedom of the molecule, perhaps mainly of twisting modes of vibration. The effect of lattice expansion accompanied by the transformation is not taken into account in the present treatment.

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The anomalous electric conductivity in higher normal alcohols is often attributed to the proton transfer accompanied by the rotation of molecules around their long axis. The direct experimental justification for the above idea is attempted, where results are described in the following. The gas produced as the result of the electric conduction is identified spectroscopically with hydrogen, and its amount is found to coincide with the expected value, assuming that the current is conducted, solely by protons. The effect of the added long chain compounds is observed and the result seems to be well understood on the basis of the proton-transfer-and-molecular-rotation mechanism.

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The dilatometric and specific heat measurements have been made on the whole range of solid solutions of (Pb-Ba) TiO₃ system. The linear thermal expansion coefficient, in the tetragonal region decreases with increasing Pb content and it becomes even negative on the PbTiO₃ side, whereas the expansion coefficient in the cubic region is almost constant independent of the compositions. Anomaly of the specific heat also increases considerably towards PbTiO₃, just corresponding to the dilatometric data and to previously reported X-ray data.

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Detailed investigations on the dielectric and the thermal properties of PbZrO₃ have been made and compared with those of ferroelectric BaTiO₃. In contrast with barium titanate, volume change at the transition near 220°C has turned out to be expansion, being δV⁄V=2.7×10⁻³, and a large amount of anomalous specific heat of ca. 400 cal./mole have been found. Spontaneous polarization estimated from the hysteresis loop, and the effects of D.C. bias upon the permittivity and especially the shift of the transition point all imply that a spontaneous polarization may not exist below the Curie point. Since the dielectric constant, nevertheless, becomes extraordinarily high at the Curie point, it must be reasonable to say that lead zirconate belongs to a new type of dielectrics, say, antiferroelectrics. When the sample contains some additional materials, a narrow region of ferroelectric phase has been observed between antiferroelectric and paraelectric ones. The temperature range of this phase is sensitively affected by the amount and the species of the additional materials.

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The temperature change in lattice parameters of solid solutions of barium titanate containing 10, 12, 20 and 25 mole per cent of lead titanate have been studied mainly by the X-ray method for the range from −130°C to 300°C. It was found that the lattice parameter-temperature curves for the solid solutions of 12 and 20 per cent lead titanate have characteristic features as follows:
(1) a-parameter-temperature curves show a considerable linearity from lower temperatures up to the Curie point.
(2) A large amount of discontinuity of a- and c-parameters takes place at the Curie point.
(3) The superposition of cubic lines upon tetragonal lines is observed in a temperature range near the Curie point. The lattice volume calculated from tetragonal phase shows an abnormal contraction.
These results are not explained by the Devonshire’s theory in its original form, but they can be explained fairly well by using higher order approximation.

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A systematic study was made on corrosion-products of iron by means of electron and X-ray diffraction, with the following results;
When metallic iron is immersed in salt solution, amorphous white precipitate, Fe(OH)₂, is formed as the primary corrosion-product.
(1) Fe(OH)₂ thus formed changes into lepidocrocite, γ–Fe₂O₃.H₂O, when pH of the solution so very low and oxidation takes place rapidly, while under usual conditions it is oxydized partly lepidocrocite, which combines with the remaining Fe(OH)₂ to form green rust, 2FeO.Fe₂O₃.H₂O.
(2) The green rust is oxydized, under usual conditions, to lepidocrocite, while in case oxygen in the solution is less, it changes partly to lepidocrocite, which combines with the remaining green rust giving magnetite, Fe₃O₄. On the other hand, when oxidation is accelerated by H₂O₂, it changes to haematite, α-Fe₂O₃.
(3) Goethite, α–Fe₂O₃.H₂O, was never observed in corrosin-products of metallic iron, and it was concluded that it is formed only from ferric salts: for example from the unstable yellow substance, which is precipitated in aqueous FeCl₃ solution under certain conditions.
(4) This very substance was assumed as β–Fe₂O₃.H₂O by Weiser and Milligan, but it is more reasonable to identify it with Fe(OH)₃ isomorphous to Al(OH)₃. Its unit cell was determined by X-ray data:- monoclinic, a=8.99, b=5.12, c=9.92 and β=86°34′.

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The size, shape and crystallinity of chromic oxides prepared by various methods have been studied. The particles of chromic oxide obtained by the calcination of chromium trioxide at 400°∼1300°C are of granular and irregular shape, while those obtained by the calcination of fluid mixture of chromium compound are plate-like, often exhibiting hexagonal shape, the fiat surfaces of these crystals being parallel to (001). Higher calcination temperature up to 1600°C merely increases the size of the particles, so that the distinction between the two types in shape remains as before.

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It was concluded theoretically that space charge may be formed in the oxide cathode layer near the surface, when electric field at the cathode surface is sufficiently strong so that the diode may be regarded to operate in the Schottky region. The calculations are carried out for one-dimensional model and neglecting the interface layer, which exists usually between the base metal and the oxide coating.
As the result of this space charge, the slope of the Schottky plots are several times greater, than that predicted by the Schottky theory for metal surfaces.
This space charge may be responsible for the microsecond emission decay observed by Sproull and others.

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Creep phenomena of selenium rectifiers, i.e. initial decaies of hard flows were observed, and polarization effects were found in the barrier layers at the same time. By observing discharge currents due to the above effect, characteristics of the polarization were studied. As the polarization voltage increases with the duration of application of the reverse voltage, the effective voltage through the barrier layer decreases, resulting the decay of the hard flow. The characteristics of the decaies were calculated on the stand points of the polarization effect and the non-uniform structure of the barrier layer. And the relaxation time of the decay was discussed by considering that the polarization effect was owing to ionic space charges in the barrier layer.

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The stress-strain curves of zinc speciemens consisting of two crystals has been studied in order to discuss the effect of grain boundaries. In each crystal of the bicrystal specimens the inclination of base plane was fixed at 50° while the angle α between the plane of grain boundary and the plane containg both the specimen axis and the direction of maximum slope of the slip plane was varied as 0°, 45°, 90°,… 315°. The specimen extended fairly well and the stress-strain curve varied systematically with the change of α in each crystal. The shape of the cross-section of the specimen changed sometimes into the, elliptical form and sometimes into the heart-shaped or the wing-shaped form according to the angle α. Moreover the specimen twisted in some cases.

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The dynamical Young’s moduli (E) and the internal friction \fracΔW2πW (ΔW: energy dissipation per cycle) of amorphous films of P.V.A. were observed under the various conditions. (1) Effect of temperature; E is almost constant at the room temperature, but it decreases rapidly beyond the characteristic temperature, which may be considered as the 2nd-order transition temperature, and it tends to the constant value at higher temperature. \fracΔW2πW increases gradually from the room temperature and saturates to the constant value at higher temperature. (2) Effect of humidity; E increases slightly up to R. H. 35% and beyond this point it decreases rapidly with increase of humidity, \fracΔW2πW is almost constant up to 25% but it increases rapidly beyond this point and tends to the constant value at higher degree of humidity. Besides, effects of tention, degree of polymerization and frequency were reported shortly. The experimental formula which represents the temperature dependence of E was devised and this formula also was suitable to the experimental results of P.V.C. The attempt to explain this formula from the statistical treatment of crystallite part and amorphous part was tried.

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The slopes of tanδ for voltage and the initial tanδ of barium-titanate ceramics, which were fired at three different temperatures has been measured in the temperature range from 150°C to −183°C. It was shown that below the Curie point the voltage region, where the values of initial tanδ did not change, were larger and the slopes of tanδ smaller, the higher the firing temperatures. Temperature dependence of the voltage region giving constant tanδ show three remarkable knicks corresponding to the phase changes of the crystals.

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Neglecting the small values of the frictional force, the resistance dRv to the elementary surface area dσ of a bullet was theoretically deduced as
dRv=\left(P₀+\fracρgv²sin²γ\ ight)sinγ·dσ
where v is the velocity of the bullet, ρ the specific weight of the aluminium, g the acceleration of the gravity and γ the angle between the surface dσ and the direction of its motion.
Finally. P₀ is the statical contact pressure acting on the surface dσ and, from the results of the statical penetration test carried out with the cylindrical mandrel, the author gave it the constant value for each thickness ε of the aluminium plates.
Assuming that P₀ is independent of the angle γ, the velocity drops suffered by the conical bullets from passing through the aluminium plates were calculated from the above equation for three values 2γ=180°, 90°, 60° of the conical angle and four values ε=3.2, 4.9, 8.2, 1.21mm respectively. (Here considered only the case of the normal attack.)
These calculated values were found to be consistent with the experimental results which were obtained with respect to the same bullets shot at the same aluminium plates by a rifle.

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A cylindrical cavity resonator of TE₀₁₃ mode was constructed and Its Q–value was measured at the frequency of 3075 Mc/sec. It was found that the Q–value is reduced, when the end-plate of the cavity is slightly tilted. The optimum Q–value (Q₀=7.53×10⁴) agrees well to that calculated from the d.c. conductivity of the wall material (copper). It may be considered that some other modes (TE₁₁, TE₁₂ and TM₁₁ modes) of waves are generated from the primary TE₀₁ mode and they are lost as heat and radiation, when the end-plate is tilted. Thereby the resonance of TE₀₁ mode is damped by mode conversion which is calculated assuming the deformation of the cavity wall is small. The calculated result agrees well to the observed Q–value of the cavity with tilted end-plate.

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The steady irrotational isentropic continuous subsonic flow of a perfect gas past an arbitary three-dimensional body with arbitary distribution of sources on its surface is considered. Based on the thing-wing-expansion method, the velocity potential Φ is expanded in the form Φ=U(x+A₁r⁻¹+A₂r⁻²+…), A₁=a₀f⁻¹, A₂=f⁻³[a₁₀cosθ+sinθ(a₁₁cosω+a₁₋₁sinω)], f=(1−M²sin²θ)^1⁄2, where U is the velocity of the undisturbed flow of Mach number M streaming in the positive direction of x-axis, and x=rcosθ, y=rsinθcosω, Z=rsinθsinω. Using this expression, the force (X, Y, Z) and moment (M_x, M_y, M_z) experienced by the body are found to be: X=ρ_∞Q_∞U, Y=Z=0, M_x=0, M_y, z=±4πa_1,±1ρ_∞U²⁄(1−M²)⁻¹, where ρ_∞Q_∞ is the total strength of sources, and ρ_∞ the density at infinity.

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Some measurements were made on the turbulence behind the grid. The wind-tunnel is of the single open-jet type and the range of test section covers from 20 to 70 times of mesh length.
In the first place, the decay of, total energy is proved to be inversely proportional to the distance from grid. Energy spectrum which is observed at various positions on the center line, is nearly the same as those previously reported. The decay of spectral components was measured directly by moving the hot-wire anemometer along the axis of wind-tunnel. In the low wave number region, energy decay follows the inverse power law. But at high wave number, decay is severer at first and gradually becomes to the state of energy equilibrium. The last result seems to be influenced by the free jet mixing.

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Spectral functions for the velocity and temperature fluctuations in heated turbulent flow are obtained in the forms:
F(k)∼ε^2⁄3k^−5⁄3, G(k)∼(K⁄K_H)²Q²ε^−2⁄3k^−7⁄3
for the intermediate scale of turbulence element (turbulon) and
F(k)∼(ε⁄ν)k⁻³, G(k)∼Q²x²k⁻⁵
for the smallest scale. Here k is the turbulon wave number, ε the rate of energy dissipation, Q that of heat transfer, ν the kinematic viscosity, x the heat diffusivity, K the turbulent viscosity, and K_H the turbulent heat diffusivity. Then the concept of smallest turbulon is defined as the intersection of two forms of the spectral function. Thus it turns out that the scale of smallest dynamical turbulon coincides with that of smallest thermal turbulon provided the Prandtl number ν/x is equal to K/K_H.

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