The excitation curve for the reaction P³¹(n, p)Si³¹ was measured in the energy range of neutron from 3.0 MeV to 5.2 MeV by activation method. A large resonance peak of 160 mb was found at the neutron energy of 4.9 MeV.

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A study is made of calculating the electronic energy bands in bismuth type crystals by making use of the Bloch method (with the inclusion of spin-orbit interaction) for the purpose of clarifing the relation between the low temperature diamagnetic susceptibility and the energy bands. The peculiar feature of the de Haas-van Alphen effect in bismuth type crystals (the small effective mass tensor) is explained by our calculated energy bands but the ordinary main term of the Landau-Peierls susceptibility expected from the energy bands is considerably small compared with the experimental value. Then, unlike Jones theory, the most part of the extraordinary large constant susceptibility seems to be attributed to the non-diagonal term which is usually neglected.

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The resonance of Cl³⁵ in α phase p-dichlorobenzene containing various impurities was studied. The used impurities were p-BrφCl, p-Br₂φ, p-I₂φ, p-OHφCl, p-CH₃φCl, p-NH₂φCl, p-NO₂φCl, p-NO₂φCH₃ and p-(CH₃)₂φ. The characteristic number which represents the number of resonant nuclei which is affected by an impurity molecule was measured. This characteristic number depends on the volume difference of the resonant and impurity molecules and independent on the difference in dipole moment. The results of the theoretical discussions supported the experiment.
The height, width, shape and the integrated intensity of the resonance line were also measured. The integrated intensity was almost constant in the range of small concentration of impurity and then decreased.

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The magnetic anisotropy constant Cr₂O₃ arising from the dipolar interactions among the chromic ions was calculated to be −0.059 cm⁻¹ per ion at absolute zero, and the magnetic anisotropy constant due to the crystalline field combined with the spin-orbit coupling was estimated from the fine-structure coupling constant of ruby and compared with that deduced from the antiferromagnetic resonance experiment by Dayhoff. The value from ruby is too large. The temperature dependence of the anisotorpy constant and that of the antiferromagnetic resonance frequency at zero field are discussed.

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Electromotive force perpendicular to the current flowing in n-type germanium samples is observed. The deviation angle of electric field vector from current vector is a function of current orientation, temperature, and field strength, and in some cases exceeds 20°. This effect can be attributed to the anisotropy in electric conduction due to the ellipsoidal energy surfaces.

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By an electron microscope Brindley, Comer, Uyeda and Zussman (Acta Cryst. 11 (1958), 99) found fringes corresponding to superlattice of about 90Å spacing in antigorite. We tried to use the fringes for magnification calibration of electron microscopes. In this paper the trial and new observations in the course of the trial are shortly described.

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Although the covalency character has been found even in the normal complexes by the analyses of the paramagnetic resonance spectra and optical absorption experiments recently performed, any reliable model for the electronic structures of complex ions has not yet been established. To clarify this problem, the electron distribution in a complex ion [Co(NH₃)₆]³⁺ is determined by means of the Thomas-Fermi method. To avoid the difficulty of multi-centre problem, the smoothing approximation is adopted. The Thomas-Fermi equation is reexamined from the stand-point of the variation principle, in order to investigate the validity of this approximation. In this paper, by the use of a trial function of spherical symmetry, the charge distributions for the total, valence- and core-electrons are calculated. Among these charge distributions, the charge distribution for valence-electrons seems most reliable and to approximate well the real situation in the complex ion. All faults brought by the smoothing approximation are discussed. In Appendix, the treatment of a trial function including an angle-dependent term is discussed.

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A fluid which comprises several species of charged and neutral particles is treated macroscopically. Basic equations, energy and momentum theorems, and law of similarity are discussed. The condition under which current equation reduces to the usual form is considered; and one-dimensional transverse waves are treated as an example. Quasi-stationary phenomena are examined as a particular case; and it is pointed out that one of the usual basic equations of hydromagnetics, the Ohm’s law J=σ(E+v×B), should be replaced by rot(E+v×B−σ⁻¹J)=0, v being the velocity of the mean mass flow. An axially symmetric solution is obtained and applied to a self-pinched column, whose stability is explained in an elementary manner.

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A new process of pinching a plasma column is treated theoretically. A column of plasma with no longitudinal current can be pinched by an external magnetic field parallel to the column; and the plasma thus pinched will not show any instability. The process depends on the effective value of γ, the ratio of specific heats. For γ=2 in particular, the temperature of a perfectly conducting plasma with no heat loss will rise in proportion to the external magnetic field.

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The analysis of the arc spectrum of iodine has been continued, and the identification of the term sequence (³P₂)nf has been fairly well completed, and some other levels newly detected. From the hyperfine structure of (³P₂)7p⁴D_7⁄2 the quadrupole moment without shielding correction was found to be Q′(I¹²⁷)=−0.63 barn, whereas the value that was deduced from (³P)6_S⁴P_5⁄2 Previously was Q′(I¹²⁷)=−0.71 barn. The mean of these two values is Q′(I¹²⁷)=−0.67±0.04 barn. This is in agreement with the value Q′(I¹²⁷)=−0.66 barn that is deduced from the hfs of the ground term 5p^{5 2}P_3⁄2 whose measurement is given in the literature. Assuming the shielding correction Δ=−0.07, the true quadrupole moment Q(I²⁷)=−0.62 barn has been obtained.

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Steady viscous flow at low Reynolds numbers passing through an infinite row of parallel circular cylinders of the same radius is investigated on the basis of the Stokes equations of motion. Tamada and Fujikawa’s expansion formula for the drag coefficient has been extended up to the 14th power of the diameter-distance ratio of the row. An alternative simple formula is presented for the case where the said ratio approaches unity so that the above-mentioned expansion formula becomes divergent. Numerical discussion is made on the drag coefficient versus the diameter-distance ratio of the row.

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The steady slow motion of an elliptic cylinder with an arbitrary angle of attack in a viscous liquid bounded either by a plane wall or by two parallel plane walls is discussed on the basis of Oseen’s linearized equations of motion. The analytical expressions for the lift and drag coefficients are obtained to a first approximation, and numerical calculations are carried out for the thickness ratio t=0, 0.1, 0.5 and 1. It is found that the wall-effect upon the lift is in either case much greater than that on the drag.

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Using Imai’s general method of solving two-dimensional Oseen’s equations, the drag and lift coefficients for one of two parallel elliptic cylinders in a uniform flow at small Reynolds numbers are calculated. When the thickness ratios of both elliptic cylinders are taken to be unity, the general expressions for these coefficients reduce to those for the case of two circular cylinders which have been obtained in the author’s previous paper. The expressions for the case of two flat plates are also included as a special case.

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Concerning the initiation of stable arcs under atmospheric pressure it is pointed out that the customary theories have some difficulties in their explanations. Considering that the boiling point of the electrode and the work function of the cathode may take part in the initiation, arcs between electrodes with remarkably different boiling points are experimentally investigated. The results are qualitatively explained by two stability conditions: (a) an arc spot of one of the electrodes at least must be in boiling state, and (b) the ionization potential of the evaporated metal vapour must be larger than double the work function of the cathode material.

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The thermoluminescence of soda-silicate glass and fused quartz, as well as ctystalline quartz, were observed below room temperature. The glow curves of glasses have broad bands without any structure. The luminescence shows the slow decay continuing for more than ten minutes at any fixed temperature between 100°K and 350°K. The dependence of these curves on the irradiation temperature and on the X-ray dose, and the effect of the heat treatments were studied. The decay curves, which do not obey the simple monomolecular or bimolecular law, are analysed by the model that the trapping levels are distributed continuously and uniformly beneath the conduction band. The discussions on the relation between the trapping centers and the random network structure of the glasses are presented.

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P. 279,   eq. (4), 2πik_r⁽ⁱ⁾·r should be read 2πik_h⁽ⁱ⁾·r.
P. 281,   2nd line of eq. (17), V_g+h′−h should be read V′_g+h′−h.
P. 281,   2nd and 4th line of eq. (17), c_hk should be read c_kh.
P. 282,   10th line from the bottom, k′≈K should be read k′≈K₀.

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P. 290,   2nd line of the equation following eq. (16), (eq. for J_s²¹_h) f′_e,g+h should be read f′²_e,g+h.
P. 290,   1st line of eq. (18), ∑\limits_t\fraccosθg_qtc_t² should be read ∑\limits_t\fraccos²θg_qtc_t².
P. 291,   left column, line 2, treat should be read treats.
P. 295,   3rd line of eq. (21), \frac12q_0² c² should be read \frac12q_0²⁄c_tr².
P. 295,   right column, 10th line from the bottom, S′ should be read S₀.
P. 296,   Reference (1), the number of page, 278, should be added.

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