The angular distributions of protons elastically scattered from Ne and inelastically scattered from Ne²⁰ (Q=−1.63 MeV) were measured from 30° to 165° in the laboratory system at bombarding energies of 4.7, 4.9, 5.1, 5.3 and 5.5 MeV. Photographic plates were employed for the detection of scattered particles. The distributions for the elastic scattering of protons varied markedly with the primary energies, while the five distributions for the inelastic scattering had roughly similar shapes.

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The angular distributions and the excitation curves of protons inelastically scattered from Si²⁸ (Q=−1.78 MeV) and Mg²⁴ (Q=−1.37 MeV) have been measured in the energy range E_p=4.8 to 5.7 MeV. A broad resonance was observed in each excitation functions. The angular distributions in Mg²⁴ show an asymmetry about the centre-of-mass scattering angle θ=90° and a strong dependence with the energy of incident protons. while in Si²⁸ the angular distributions are rather symmetric than in Mg²⁴.

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An observation of extensive air showers has been performed at Mt. Norikura (2840 m above sea level and 25°N geomagnetic latitude) by the aid of two multiplate cloud chambers, sparsely distributed 90 GM counters and two sets of counter hodoscope pile. In this experiment, the structure of the air shower in the neighbourhood of shower axis was mainly investigated.
For each observed air shower, the shower size, N, and the location of the shower axis were estimated. The air showers were divided into three groups characterized by the core structure which depends upon the shower size. The first group is of the small size shower (less than 1.5×10⁵) which has comparatively poor core which fluctuates by the behaviour of a few high energy particles. The second group is of the middle size shower (1.5×10⁵–5.5×10⁵) in which the decaying nuclear component and the electron component are in state of equilibrium, and the electron component lateraly distributes as proportional to 1/r in particle density and 1/r² in energy flow near shower cores. The third group is of the large size shower (larger than 5.5×10⁵) which contains many high energy nucleons and they are thought to be yet in the state of active nuclear cascade.
Integral size spectrum was obtained as 6.1×10⁻⁹(N⁄10⁵)^−1.5 cm⁻² sec⁻¹ sr⁻¹ for the showers with a total number of particles 1.5×10⁵–5.5×10⁵ and for large size showers the exponent of the spectrum increases with shower size reaching about −1.9 at N=10⁶.

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The dependence of carrier lifetime in pure germanium upon injection level has been studied using a photoconductivity decay method. The data are analyzed in terms of the recombination theory for transient conditions including the case of high injection level. The results show that at least two recombination levels exist in pure germanium: one is active in n-type and the other in p-type. The recombination level in n-type germanium is at 0.28 eV from the conduction band and the cross section for capture of holes A_p is about 4.7 times larger than that for capture of electrons A_n. On the other hand, the recombination level in p-type germanium is at 0.25 eV from the valence band or 0.31 eV from the conduction band and A_n⁄A_p is about 9.8.

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Etch pits of KCl crystals obtained with dehydrated glacial acetic acid were observed. KCl is so soft, comparing with LiF, that dislocations are generated on it by slight mechanical shocks. Therefore, surfaces of KCl crystal are apt to be contaminated in the sense of the dislocation theory. It is supposed its depth usually reaches 100 μ or more and also most of these generated dislocations are surface half loops and isolated loops. One to one correspondence between etch pits and dislocations is discussed.

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The internal friction of BaTiO₃ ceramics has been studied under various conditions. It depends on temperature, biasing field and vibration amplitude, but is nearly independent of frequency and porosity. It is concluded that its main part is not caused by the ceramic and domain structures but is the property of the single domain crystal, which is of intrinsically dielectric origin, acting through piezoelectric coupling.

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In the part I of this article, it has been shown that the thermoelectric power of monovalent metals at high temperatures is interpreted, at least semi-quantitatively, based on the spherical energy band model. However, it has also been shown that the model gives no possibility of the positive sign of the thermoelectric power of pure metals at low temperatures. Therefore, in this part II, the thermoelectric power at low temperatures is calculated for an arbitrarily anisotropic energy band. The results show that there is a possibility to give positive thermoelectric powder for pure metals at low temperatures if the shape of the energy surface is appropriate. The relation with the spherical band model used in I is discussed also.

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The effects of heat treatments on the magnetic properties of the synthesized solid solution xFeTiO₃–(1−x)Fe₂O₃ of ilmenite and hematite were examined in detail for compositions x around 0.5. It was confirmed that a transformation from an ordered state (ferrimagnetic one) into a disordered state (antiferromagnetic one) takes place cooperatively at a distinct transition point. This transformation temperature is lowered with decrease in the ilmenite content from 1100°C for x=0.65 to 600°C for x=0.45. The completely disordered specimens could not be obtained for the composition x≥0.6 by the quench method while the completely ordered state could not be attained in the specimens with x≤0.5 because of decrease of the transformation temperature for these specimens and a reduction of the rate of ion diffusion at such low temperatures. The results obtained were discussed by using the Bragg-Williams approximation. It was noted briefly that the reverse thermo-remanent magnetism found in this system is closely related to the order-disorder transformation phenomenon which exists in this system.

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The diffusivity of cadmium into single crystals of copper has been measured in the temperature range from 725°C to 950°C using radioactive isotope Cd¹¹⁵ as a tracer. The results indicate that D₀=0.935 cm²/sec and H=45,700 cal/mol. These values are compared with the corresponding values for the diffusion of zinc into copper in order to investigate the effect of the difference in atomic radii.

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The diffusivities of CO⁶⁰ into 50–50 atomic percent iron-cobalt alloy were measured by means of the lathe sectioning method for the temperature range including f.c.c. to b.c.c. phase transformation. The experimental values were expressed by
D=1.1×10⁻⁴exp (−41800⁄RT) cm²/sec for f.c.c. structure,
D=2.6×10⁻⁶exp (−27400⁄RT) cm²/sec for f.c.c. structure.
The activation energies for diffusion in the b.c.c. and f.c.c. lattices were compared with the theoretical values calculated by the approximation of the closed shell repulsion with the Born-Mayer potential. And it is concluded that the vacancy mechanism is responsible for the diffusion in the body centered cubic metal in the same manner as in the face centered cubic metal.

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The measurements of diffusion coefficient of cobalt into copper have been carried out in the temperature range from 950°C to 700°C using Co⁶⁰ as tracer. The result indicates that the diffusion coefficient is given by the equation D=5.7exp (−55200⁄RT) cm²/sec and, therefore, that the activation energy is appreciably larger than that of copper self-diffusion. From this experiment it has been definitely shown that, for the negative value of excess valency Z, the effect of screening on the solute diffusion in metals plays an effective role in the same manner as the effect observed for the positive value of Z.

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In the interpretation of the fine structure of the X-ray absorption spectrum in solids, the life time of the state of the electron ejected by absorption of a photon is considered. The life time is mainly determined by the inelastic collision cross section between the ejected electron and the atoms in the crystal. With the assumption that the inelastic cross section has a magnitude of the order of one square Angstrom, Kronig’s method for the molecule is applied to the solid in order to obtain the variation of the transition probability. The wave function of the final state of the transition is obtained as the sum of the plane wave, whose amplitude decreases with increasing distance from the absorbing atom, and the waves scattered by the neighboring atoms. The calculated results for the K-absorption spectra of copper, nickel and iron agree well with experiments.

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The pure quadrupole resonance spectra were observed on Cl³⁵ and Cl³⁷ in BCl₃ and Br⁷⁹ and B⁸¹ in BBr₃ at several temperatures. The spectrum of each nucleus consists of characteristic doublet (ν_I and ν_II) with the intensity ratio of ca. 3 to 5. The Zeeman study with a single crystal of BBr₃ was also carried out at liquid nitrogen temperature (77°K), to determine the asymmetry parameter η. The results are as follows:
(Remark: Graphics omitted.)
The ionic character and the double bond character were estimated to be i=0.42 and f=0.11, respectively for the B–Br bond from the above results. In BCl₃, f=0.06 was obtained by assuming i=0.50. The double bond characters of these compounds are fairly smaller than usually assumed.
The doublet separation cannot be explained by direct nuclear dipole-dipole interaction. A reasonable explanation was made by taking into account the effect of the intramolecular vibration: the isotopes of boron B¹⁰ and B¹¹ provide different mean square amplitudes to the bending vibrations of BX₃, which in turn produce a difference of q for B¹⁰X₃ and B¹¹X₃ molecules. The effect was calculated by use of the normal frequencies of BCl₃ and BBr₃. A fair agreement was obtained between the observed separation of the doublet and hte calculated one. The observed intensity is also compatible with the assumption.

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A study on the Zeeman effect of Cl³⁵ nuclear quadrupole resonance spectrum was carried out on a single crystal of cyanuryl chloride. Three distinct q-tensors were found in this crystal, two of them being equivalent. The directions of the principal axes were determined within the accuracy of 1°. It was concluded that in the crystal all molecules are disposed parallel (or antiparallel) to one another and three C–Cl bonds of a molecule are on a plane, making an angle 120° with one another, one of them being not equivalent to the other two. A large asymmetry parameter, 0.26, was obtained. From the coupling constant and the asymmetry parameter, the double bond character and the ionic character of C–Cl bonds were estimated to be 10% and 17%, respectively. The large double bond character was considered to be associated with the large electronegativity of nitrogen atoms in the ring.

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In the frame-work of the crystalline field theory, the excited states of Cr³⁺ in Al₂O₃ and the optical transitions to these states are studied taking into account the effect of trigonal field and spin-orbit interaction. Initial splittings and optical anisotropies of the broad band (transitions to quartet states) and the sharp lines (transitions to doublet states) are examined. For the sharp lines, the Zeeman effect is also examined and the Zeeman patterns are predicted. Comparing these theoretical results with those of the experimental ones given in Part B, the assignments of U, Y bands and R₁, R₂, B₁, B₂ lines have been established. It is shown that the g-shifts of the excited doublets observed in the Zeeman patterns can also be explained under such assignments. It is also shown that the experimental data of the optical absorption can be reasonably connected to those of the paramagnetic resonance absorption.

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The absorption intensities, widths and wave-numbers of R₁, R₂ and B₁ B₂ lines of Cr³⁺ in ruby for the polarized light E⊥C₃ and E\varparallelC₃ are experimentally studied at 20°K and 4.2°K. Zeeman effect is also studied, using a magnetic field H₀=24,000 φ, for both R and B lines. The Zeeman effect has not been observed yet for the B lines, while Lehmann has already observed the Zeeman effect for R lines. In our results of R lines, the quantitative aspects of Lehmann’s experiment are improved. The comparison is made with the theoretical results given in Part A and it is shown that nice agreements can be obtained when suitable assignments of the spectra are adopted and when fairly large g-shifts of the excited states are introduced.

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Using transient techniques, the free induction decay time T₂^* and the spin-lattice relaxation time T₁ were measured for Br⁷⁹ and Br⁸¹ in NaBrO₃ at room temperatures. The free induction decay curves were well described by Gaussian curves with T₂^*=10.2×10⁻⁵ sec for Br⁷⁹ and 9.8×10⁻⁵ sec for Br⁸¹. Comparison was made with the result of the steady-state measurement. The measured values of T₁ were 2.1×10⁻³ sec for Br⁷⁹ and 3.0×10⁻³ sec for Br⁸¹. The agreement of the ratio T₁(Br⁸¹)⁄T₁(Br⁷⁹)=1.4 with the known ratio Q²(Br⁷⁹)⁄Q²(Br⁸¹)=1.44 indicates that the quadrupole relaxation is principally responsible for spin-lattice relaxation. The apparatus and procedures are also described in some detail.

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Principal axis systems and asymmetry parameter of the electric field gradient tensors were determined by studying Zeeman effect of nuclear quadrupole resonances of As⁷⁵ and I¹²⁷. The iodine resonance in AsI₃ showed that there are three principal axis system swhose z axes form a trigonal pyramid having an apex angle of 91.7°±2.5°. The fact that this angle did not agree with the bond angle of 88°02′ supports the mechanism of resonance switching of the bond. The arsenic resonance in AsI₃ has only one principal axis system whose z axis is along the trigonal symmetry axis of arsenic tri-iodide molecule. The asymmetry parameter obtained from Zeeman study was nearly zero.
The iodine resonance in AsI₃·3S₈ also showed that there are three principal axis systems. This fact well agrees with the result from X-rays that the most possible crystal structure of AsI₃·3S₈ is C_3v¹. Three z axes are parallel to the edge of a trigonal pyramid with an apex angle of 101.7°±0.5° which is close to the bond angle 100°±2° (∠ I–As–I) of AsI₃ molecule in gaseous state. The electric field gradient tensor of arsenic resonance in AsI₃·3S₈ was nearly axial symmetric about the trigonal symmetry axis of the molecule.

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The studies on the configurations of a linear high polymer have based upon the problems of the random flights which have been discussed so far mainly in the form of the Fourier transformation. In this paper these problems being treated by the operational method, the general expressions for the distributions of the end-to-end distance, of the distance between the i-th segment and the centre of gravity and of the segment density around the centre of gravity are obtained. It can be seen that it is rather preferable for the random flights of which each displacement has finite length to use the operational method. This method can be applied to the general random flights problems by adopting the discontinuous integral in the form of the Laplace transformation.

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The distribution of electrons around a vacancy in metal is studied using a model which was introduced in our previous paper in order to treat the impurity atom.
The arrangement of nuclei of matrix metal at each lattice point, except one where the nucleus is missing, i.e., vacancy, is treated by the cellular method. The deviation of the potential in the cells neighboring to the vacancy, from the periodic one for the pure metal is taken into account. In the first approximation, the lattice distortion due to the vacancy is neglected.
The Thomas-Fermi equation, in which all the electrons, i.e., valence electrons as well as core ones, are taken into account, is solved numerically in each cell and connected smoothly by a suitable set of boundary conditions.
As a result of our calculations for the case of a vacancy in copper, we find that there is the charge of −1.7e inside the atomic sphere for the vacancy.

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Experimental investigation of the characteristics of the ammonia maser is given and compared with theory. Observed saturation characteristics agree fairly well with the theory descibed in the previous paper. The change of oscillation frequency shows the expected increase with focuser voltage which arises from unresolved hyperfine structure of the 3,3 line. Small discrepancies are explained by the velocity distribution and different saturation of each hyperfine component. Frequency pulling due to cavity detuning was measured in detail and compared with theory. Thus the velocity spread of the effective molecules in the cavity can be estimated as roughly ±30%. Tentative estimate of the center frequency on UT2 is compared with other measurements.

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A dispersion relation for a self-pinched plasma column enclosed by a conducting wall is derived for the case of a model with both surface sheet current and uniform volume current. On the basis of this dispersion relation the maximum disturbance growth rate for the instability is calculated. Both the uniform volume current and longitudinal magnetic flux outside the plasma column decrease the stability and make the growth rate faster, the effect of the magnetic flux being larger.

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The steady flow of a viscous liquid past an elliptic cylinder at an arbitrary angle of attack is discussed on the basis of Reynolds number expansion using conformal transformation of the general solutions of Oseen’s equation, which are expressed in integral forms. Thus the expansion formulae for the lift and drag coefficients are obtained to the second approximation, which are in perfect agreement with the results obtained recently by Hasimoto and also by Imai. Although it seems difficult to obtain general expressions for various formulae, such as formulae for the lift and drag, the procedure gives not only a practical method of solving Oseen’s equation for the two-dimensional slow steady flow of an unbounded viscous liquid past an arbitray cylindrical body, but also an effective method to study the wall-effect upon a cylinder of arbitrary shape moving in a viscous liquid bounded either by a plane wall or by parallel plane walls, provided the mapping function is known for the cylinder.

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The adsorption of water vapour on lead borosilicate glass was studied in the pressure region 10⁻⁵∼10⁻⁶ mmHg using the modified flashing technique.
The adsorption is composed of at least two parts, the physical adsorption and the activated adsorption. The amount of the physical adsorption at 1×10⁻⁶ mmHg, 0∼50°C was 0.1∼0.4% of a monolayer, and the heat of adsorption was 11 Kcal/mole. The activation energy of adsorption of the activated adsorption was ca. 9 Kcal/mole, and the activation energy of desorption was 13∼40 Kcal/mole.

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