In this calculation of the low lying energy levels of Mn⁵⁵, the same treatment as in our previous note is extended from the standpoint of the configurational mixings. One assumes that the potential between nucleons is V(r₁₂)[1+a(σ₁·σ₂)]: V(r)=V₀e^{−r2⁄r₀2}, and the wave functions are the harmonic oscillator type due to Talmi. λ is the ratio of the potential range r₀ to 1⁄\sqrtν which determines the extension of the wave function. The values of a and λ are determined from the experimental data of the energy splittings of the J=0, 2 and 4 levels for Fe⁵⁶. And for these values of parameters, the competition of the low lying levels J=7⁄2, 5/2 and 3/2 for Mn⁵⁵ is discussed.

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The angular and energy distributions of alpha particles resulting from V⁵¹(n,α)Si⁴⁸ and S³²(n,α)Si²⁹ reactions induced by 14.8-Mev neutrons were measured with Ilford C2 nuclear plates. It was found that the angular distributions for the entire energy regions in the center-of-mass system are concave upward and approximately 90° symmetrical, and the energy distributions show that the alpha particles with energies below the Coulomb barrier are more emitted than expected. Also the curve on a semilog plot of the relative level density calculated from the energy distributions of the alpha particles fits a straight line which would correspond to Maxwellian distributions with the temperatures of about 0.9 Mev for Sc and about 1.5 Mev for Si.
The total cross sections of V and S are 126 mb±15% and 109 mb±15% respectively. Experimental data on (n,α) reaction so far obtained by us are summarized and discussed in detail.

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The phase relation and the dielectric and mechanical properties of ceramic samples on the ternary system (Ba–Pb–Ca)TiO₃ are studied. The ferroelectricity of the solid solution (Ba–Pb)TiO₃ decreases with increasing Ca concentration and disappears at about 50 mole percent of CaTiO₃; and then the structure changes to cubic, pseudocubic and orthorhombic. A certain insoluble region exists in the vicinity along (Ba–Ca)TiO₃ side. The dielectric and piezoelectric constants of BaTiO₃ decrease with increasing concentration of PbTiO₃ and CaTiO₃. The dielectric and mechanical Q’s vary in parallel with composition.

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The electronic conductivity, σ_e, Hall constant, R, and thermoelectric power, Θ, in α Ag₂Te are measured as the Ag/Te ratio is varied by the use of the galvanic cell Ag|AgI|Ag₂Te|Pt, where the e.m.f. of the cell, E, represents the position of the Fermi level relative to Ag-saturated Ag₂Te. According as Ag is removed across the cell, starting from the Ag-saturated composition, σ_e decreases at first, and then increases. Θ changes its sign at the minimum of σ_e, although R is always n-type, duing to the large mobility ratio (∼100). The energy gap is, therefore, as narrow as several kT. When Ag is removed further, σ_e decreases again, keeping E constant. This is a mixed state of Ag₂Te and a new phase mentioned below. After a minimum of σ_e is attained, σ_e and E increase again, suggesting a new phase, Ag_∼1.93Te. The energy gap of this phase is fairly larger than that in Ag₂Te phase and the mobilities of electron and hole are far smaller than those in Ag₂Te. When Ag is removed still further, σ_e and E become to be independent of the composition, indicating the precipitation of Te or Te rich compound. Those experimental data are compared with the Lorentz-Sommerfeld theory, proving a good accordance between them. On the other hand, ionic conductivity is estimated from the ionic polarization effect.

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It has been observed that the “creep” phenomenon often found in the backward direction of the alloyed germanium p-n junction occurred in the so-called “leakage current component”. It has also been found that in some of the alloyed junction transistor samples, the characteristics of the collector junction was influenced by the creep in the emitter junction. The experimental procedures and results are described.
Although we have no complete theory to explain these experimental observations at present, some essential remarks are given from theoretical consideration. In the last section, an experimental result which might be an evidence for the correlation between the creep phenomenon and the surface field effect is given.

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WO₃ is monoclinic at room temperature and has a domain structure with walls of (110) and (100) twin planes. The (110) wall is displaced sideways by a pressure externally applied along the b axis, resulting in the change of the axis b to the shorter axis a. The (100) domains change to a single domain by stress X_z. The single domain crystal obtained in this way is used to determine the optic elasticity axes of WO₃. Two peculiar types of domain structure appear by a pressure along the c axis, which can be understood as resulting from the change of the axis c to the axis a by the stress. This sensitivity of domain structure to the stress seems to be due to the monoclinic and pseudosymmetric structure of this crystal.

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The phase diagram of the mixed crystals composed of NaK-tartrate and its isomorph NaNH₄-tartrate has been investigated over the whole range of the concentration. The properties of each phase have been studied by dielectric and pyroelectric measurements and by optical observations. In 90.5 per cent NaNH₄-tartrate crystal three kinds of polymorphic modification have been found, that is, successively, a ferroelectric phase with spontaneous polarization along the crystallographic b axis, another ferroelectric phase with spontaneous polarization along the crystallographic a axis and a paraelectric phase. The phase of compositions near the pure NaNH₄-tartrate has been confirmed to be ferroelectric with spontaneous polarization along the b axis.

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The change of carrier-concentration with static magnetic field is discussed by using the simple model of the semiconductors. The attention is mainly focused on whether the concentration of free carriers increases or decreases with the field. The situations are classified into three cases [A], [B] and [C] according to the degree of concentration of the centers.
[A] The concentration of the trapping centers is dilute and a center can trap only one carrier. In this case the carrier concentration n is a monotonously decreasing function of the field H, namely dn⁄dH²≥0,
[B] The impurity levels lose the locality and form a band so called “impurity band,” however, the width of which is still smaller than kT. In this case we obtain
(dn⁄dH²)_weakH>0when(m⁄m^*)<\sqrt3δ
(dn⁄dH²)_weakH<0when(m⁄m^*)>\sqrt3δ
where m^* is the effective mass of carriers and δ means the degree of compensation, namely δ=(N_d−N)⁄Nd.
[C] The width of impurity band is larger than kT and the Fermi-level ζ₀ at H=0 lies in this band. In this case we obtain
(dn⁄dH²)_weakH>0when(m⁄m^*)<\sqrt3(1−s)
where
s=kT\left[\frac∂∂ElogD(E)\ ight]_E=ζ0
D(E) means the state density of the impurity band.
It seems that there is no possibility to explain the so-called “magneto-conductive” phenomena observed in p-InSb from this stand-point.

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The change of carrier concentration with static magnetic field in a single crystal of graphite is considered and the Hall coefficient R is discussed from this point of view.
The Wallace’s model of the two dimensional zone and its orbital quantization proposed by McClure are the starting point of the analysis. By comparing with the Kinchin’s experiment we propose that the acceptor levels exist at 11×10⁻³ eV. above the bottom of the conduction band and their concentration is 1.7×10¹⁸/c.c.. As to the Wallace’s resonance integral γ₀ we estimate its value as 1.43 eV. semiempirically. The ratio of the mobilities of two carriers b=μ_p⁄μ_n=0.87 gives the best fit of R at the low temperature under the strong magnetic field. By using these resonable values of the parameters the Hall coefficient R is plotted as the function of temperature and magnetic field. The agreement with experimental data may be good except the low field region. The origins of discrepancy are discussed.

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The dissociations in the excited states of the derivatives of naphthalene, i.e., α- and β-naphthylamine, and α- and β-naphthol are discussed by the molecular orbital treatment using semi-empirical L.C.A.O. method. The difference of the proton dissociation constant between the excited and the ground state, pK₁–pK₂, is expressed by a certain parameter connecting the coulomb integral with the basic strength of attached groups. The value of the parameter is derived by the light absorption spectra of the similar molecules. The calculated values of the differences, pK₁–pK₂, are 5.0 and 5.5 in the case of β-naphthylamine and α-naphthol in good agreement with the experimental values of 6.0 and 6.0 respectively. The similar calculations for the case of β-naphthol give considerably smaller value of which discussion is given briefly as well as the experiment.

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It is shown that the matrix elements of the crystalline field of lower symmetry than cubic and of the spin-orbit interaction for d-electrons in octahedral complex ions can be easily evaluated by the method of tensor operators, and the tables necessary to evaluate these elements by this method are given. It is also pointed out that the effective Hamiltonian which plays the same role as the spin Hamiltonian for the non-degenerate states can be constructed for the degenerate orbital states and will be useful for the analysis of line spectra of these complexes.

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A new probe method is proposed. This method is based upon the idea that the end of a cylindrical probe affects the surface area of the sheath. The first stage of this method is to measure the sheath radius by using a variable-length structure. The procedure is to extrapolate the probe current to l=0 along the straight line of the plot of current vs. length of probe and to measure the slope of the straight line and thus to derive the radius of the sheath. Experimental results of ion sheath for Ar are fairly well consistent with the theoretical radius expected from simple theories, except for low plasma density. The discrepancy between the theory and the experiment is caused by the disturbance.
By taking into account a correction factors, namely, depletion in ion collection due to elastic scattering, plasma density can be exactly estimated by measuring the radius of ion sheath without having any know-ledge of the adequate space charge equation. Thus, the reliability of the probe method is increased.

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Oscillation of the pure laminar wake behind a flat plate placed in a uniform stream at zero incidence angle was investigated experimentally at Reynolds numbers between 10² and 10⁵. (The Reynolds number R is Ul⁄ν, where U is the model speed, l is the plate length and ν is the kinematic viscosity.)
For a sufficiently small R the corresponding wake was perfectly laminar and vortex filament was seen nowhere. But when R of about 700 was reached, the wake began to oscillate sinusoidally some distance downstream. As R was increased further the oscillation became more and more conspicuous and discrete vortex filaments appeared in the loop of the sinusoidal wave. Frequency N was measured by the hot-wire technique and it was found that the Strouhal number Nl⁄U is nearly proportional to 1/2 power of R. On the other hand, wave length λ was determined from the photographs taken by aluminium dust method, and the relation between l⁄λ and R was obtained. Spacing ratio and velocity of the vortex filaments were also estimated.
These experimental results were compared with those of the wakes behind various bluff bodies, and some knowledges about the origin of oscillation of the wake were obtained. The value of wake Strouhal number was nearly constant for all shapes of body, while the wave velocity changed remarkably with the shape of the body.

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