The directional correlation and the polarization-direction correlation of the 1.03 Mev–1.17 Mev gamma-gamma cascade in Sn¹²⁰ have been measured. It is found that the spin and the parity of the second excited state of Sn¹²⁰ is 4 and even, respectively.

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The proton and neutron separation energies and the β-decay energies are estimated for most of the nuclei that have been dis- covered or will be discovered in near future. In this estimation four semi-empirical rules for the proton and neutron separation energies are used in addition to the available experimental data. These rules are also used to eliminate the wrong data and to correct the wrong interpretations of the experimental results. The “best” values thus obtained are tabulated. Explanations are given for some of the data which are eliminated or need large adjustments.

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The angular distribution for the N¹⁴(d, α)C¹² ground-state reaction was obtained at seven deuteron energies between 1.5 and 3.0 MeV, and the excitation function for this reaction at the laboratory angle of 30° was determined in the same energy range of deuteron. The angular distribution varies remarkably with deuteron energy, suggesting that the reaction proceeds mainly via compound nucleus formation. The energy dependence of the 30°-differential cross section and the total cross section indicate the presence of overlapping resonances at the excitation energy of about 22.6 MeV in the compound nucleus, O¹⁶.

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The energies and spins of lower excited levels in Nd¹⁴⁴ have been established by studies of the beta decay of Ce¹⁴⁴–Pr¹⁴⁴ and the electron capture decay of Pm¹⁴⁴. The experiments include the energy and relative intensity measurements, and directional correlation measurements of gamma rays by several NaI (T1) scintillation counters. The level of Nd¹⁴⁴ is populated at the 695 keV and 2190 keV from decay of Pr¹⁴⁴, and the 695 keV, 1310 keV, and 1780 keV from the decay of Pm¹⁴⁴. The levels at the 1220 keV and the 1560 keV which have been found by the neutron capture gamma ray measurements could not be found in both decay in the limit of about one percent.

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The magnetic susceptibilities of Cr and Cr-Fe are investigated by the use of the band picture for 3d electrons. The temperature increase of the magnetic susceptibility of Cr is attributed to a minimum of the electron state density. For the shape of the band of Cr two models are adopted, and the calculated susceptibilities are compared with the observed ones. According to this comparison the shape of the band of Cr is discussed, and the result on its shape is compared with that calculated from the specific heat measurement at low temperatures by Cheng et al.

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The character and magnitude of the exchange interaction between the ferric ions in K₃Fe(CN)₆ have been investigated by, (1) observation of the paramagnetic resonance spectrum of coupled Fe-Fe pairs in semi-dilute crystals and, (2) adiabatic demagnetization of concentrated crystals. The results show that the exchange between magnetically similar ions contains an appreciable anisotropic part of the order of 0.07 cm⁻¹. No lines corresponding to dissimilar ion pairs were found. From the two types of experiments, it is concluded that the isotropic part of exchange between similar ions, J_s, is about 0.25 cm⁻¹ and that the exchange between dissimilar ions is very small.

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The effects of the reduction of free electron density due to the dislocation-acceptors and the scattering due to the space charge around the dislocation on the thermoelectric power of n-type materials are theoretically investigated in the temperature covering from impurity- to transition-range and compared with the experimental data for near intrinsic n-Ge in only the transition range of temperature. In the intrinsic range of temperature the scattering effect due to the lattice deformation around the dislocation is discussed and compared also with the experimental data.

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The changes of the thermoelectric powers and the electrical resistivities of several kinds of n-Ge and p-Ge due to plastic bending are measured in the temperature covering the transition- and intrinsic-ranges and analyzed by the theory. The value of the dislocation-acceptor level is estimated to be about 0.2 eV. The n-Ge sample near intrinsic is converted to p-type by the bending, while n-Ge with low resistivity and p-type samples show the slight effect. The difference of n-p conversion due to the deformation from the thermal conversion is discussed.

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An explanation is given on the divergent beam pattern due to Compton scattering. The pattern is not caused by a point source of X-rays outside of crystal but by interference of X-rays produced uniformly in a small crystal. It is shown experimentaly that the interference lines can appear even for a pretty small crystal if a micro-beam is used.

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The crystal structure of NiCl₂·6H₂O has been determined by the X-ray single crystal method. The unit cell is monoclinic with a=10.23 Å, b=7.05 Å, c=6.57 Å and β=122°10′. The space group is C_2h³–C2⁄m and the unit cell contains two formula units. The atomic arrangement is quite the same as that of CoCl₂·6H₂O and thus the structure model adopted for this salt has again been confirmed to be correct, as compared with the model proposed by Stroganov et al..

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The result of the transverse and longitudinal wave measurement on two groups of high polymers were presented as a function of temperature at frequency of 2.5 Mc. One group contains those polymers with no or slight steric hindrances, i. e. polyvinylchloride, vulcanized rubber and polytrifluoromonochloroethylene. The other includes the materials with strong steric hindrances i. e. polyethyl methacrylate, poly-n-butyl methacrylate and poly-i-butyl methacrylate.
The relaxation of shear deformation can be explained by the widely distributed relaxation times irrespective of the coupling between the molecules and the steric hindrance of side chain groups on the main chain. On the other hand, the relaxation of volume deformation depends on the intermolecular force and the steric hindrance. In poly-i-butyl methacrylate, the relaxation associated with volume deformation may be explained by the single relaxation theory.

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The shape of ionization efficiency curves (I. E. curves) obtained by essentially monoenergetic electron is studied by means of the threshold law. In the I. E. curves for N₂⁺ and CO⁺, some humps which are attributed to autoionization processes are found. These processes occur at 16.2±0.1 eV for N₂⁺ and at 15.6±0.1 eV and 18.4±0.1 eV for CO⁺. Though the shape of I. E. curve for Kr⁺ obtained in this work is similar to that of Fox et al and Frost et al, it is difficult to interpret this shape by autoionization process only. The I. E. curve for A⁺ shows large tailing of 0.50±0.05 eV which can not be explained by doublet of ground state of A⁺. The ionization potentials determined for rare gases and some diatomic molecules agree well with spectroscopic values and the previous electron impact data.

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The multiple quantum process in the off-resonant condition of the three-level gas maser is discussed. The intensity of the emission produced by this process is calculated by a perturbation theory and also by a more general treatment which is the application of Javan’s theory to the off-resonant case. Some graphical representations of the signal line under off-resonant pumping are given for the purpose of comparison with experiment.
The Doppler effect in three-level maser action is analyzed from both semiclassical and quantum mechanical points of view under the presence of collision relaxation. It was shown that in a saturation process between two levels, Doppler effect behaves as to contribute to both line-width and relaxation time for the transition, and that under strong pumping, Doppler effect in pumping transition has a marked influence on both intensity and shape of the signal line through the effect of multiple quantum transition.

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Absorption, emission and excitation spectra of KCl:Pb and KBr:Pb have been measured at various temperatures. These observed spectra are similar to those of KCl:Tl, and the absorption bands seemed to be due to transitions in Pb⁺⁺ ions which occupies the normal positive ion sites. The two principal excited states are ¹P₁ and ³P₁ of Pb⁺⁺ ion. 273 mμ absorption, 345 mμ emission in KCl:Pb and 302 mμ absorption, 365 mμ emission in KBr:Pb are attributed to ³P₁–¹S₀ transitions perturbed by surrounding host lattice ions. The excitation to ¹P₁ state does not manifest any dstinct emission which is different from the case of Tl activated phosphors. The near ultra-violet emission suffers violent thermal quenching at room temperature, and the activation energies of these non-radiative process are found to be 0.28 eV and 0.18 eV for KCl:Pb and KBr:Pb, respectively.
Several discussions using a single configuration coordinate model are given.

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The local properties of the rotational flow field behind a steady, two-dimensional, curved shock wave which occurs in a supersonic uniform flow of a perfect gas are considered. The states of flow field in the vicinity of a point on a shock wave are described as a power series about this point under the assumption that the shape of the shock wave is regular. The hodograph transformation of such a field becomes singular at the points where Jacobian relating to the transformation vanishes. The fields in the vicinity of such singular points are discussed in detail.

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The behaviour of the two-dimensional supersonic jet of an ideal gas with weak electric conductivity in the presence of a uniform magnetic field is considered on the basis of the linearized theory. In general, the boundary of the jet can be expressed by the formula which contains the terms yielding the monotonic change of the width of the jet and its deflection due to the inclination of the lines of force in addition to the term in the ordinary gasdynamics. The expressions for these terms are shown explicitly.

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Classical methods are used to determine the steady temperature distribution in a finite elliptic cylinder consisting of any number of plane-parallel layers. As illustration of the general procedure, the case of a homogeneous isotropic elliptic cylinder is treated in some detail.

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The study of dispersion of acoustic velocity in acetone employing ultrasonic waves of very high frequencies up to 180 Mc/s has been made for the first time and no positive evidence of dispersion could be established. It is shown that the angular distribution of high frequency diffraction is less in acetone than that in water, as this depends only on the parameter πL⁄λ^* where L corresponds to the length of the sound path traversed by the light beam and λ^* corresponds to the sound wave-length in the medium.

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p. 1209, Table IV. The F_c’s for the following reflections should be given negative signs.
(400)   (600)   (130)   (190)   (220)   (240)   (260)   (280)   (2   10   0)   (350)   (370)   (390)   (4   10   0)
(660)   (680)   (008)   (00   12)   (021)   (025)   (027)   (028)   (029)   (02   11)   (02   13)   (02   15)   (02   19)
(02   20)   (02   21)   (041)   (047)   (04   11)   (04   13)   (04   17)   (069)   (06   13)   (06   17)   (06   17)   (083)
(084)   (087)   (089)   (08   11)   (08   15)   (0   10   1)   (0   10   5)   (0   10   7)   (0   10   9)

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