Gamma ray spectra and intensities from C, O, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Cu, Ag, Cd, Sn, Pt, Au and Pb bombarded by 10 and 14 MeV protons have been studied.
For C, O, Mg, Si and Ca, most of the gamma rays could be attributed to the inelastic scattering. New levels at 7.08 and 8.13 MeV are suggested in ⁴⁰Ca.

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Angular and energy dependence of the elastic and the inelastic scattering of protons from nickel isotopes, Ni⁵⁸ and Ni⁶⁰, were investigated in the energy range from 7.0 MeV to 15.3 MeV. Angular distributions in the high energy region (E_p≥10 MeV) showed small difference between both isotopes. Energy dependence of the differential cross sections in the low energy region (7 MeV <E_p<9 MeV) showed some fluctuations both for the elastic and the inelastic scattering. The inelastic yield for Ni⁵⁸ was larger than that for Ni⁶⁰ in the low energy region (E_p≤9 MeV). These yields decreased gradually as the incident energy increased. The results of present work are compared with our previous one and with the investigations of Thirion et al., Greenlees et al., and Seward.

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Angular distributions of alpha particles scattered elastically and inelastically (Q=−4.43 MeV) by carbon nucleus were measured with incident alpha energies of 28.4, 31.0 and 33.6 MeV.
Angular distributions of inelastic alpha groups corresponding to Q=−7.66 and −9.63 MeV and a broad alpha group with Q\simeq12.7 MeV were also obtained at E_α=28.4 MeV. The data were compared with Blair’s diffraction scattering model and fairly good agreements were obtained for both elastic and inelastic (Q=−4.43 MeV) angular distributions for forward angles for three energies. The rises of cross sections at back angles, however, seem to occur from other mechanisms. Spin and parity assignments were tried for 7.66 and 9.63 MeV levels of carbon.

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Extensive experimental results are presented, showing the variation with energy of the absolute angular distributions for the elastic and inelastic scattering of medium energy protons on oxygen.
For the elastic scattering, angular distributions between 20 deg and 160 deg were obtained for twenty incident proton energies spaced between 6.87 MeV and 15.6 MeV. The absolute angular distributions for the inelastic proton groups, leading to the excitation of about 6 MeV (6.06 and 6.14 MeV) and 7 MeV (6.92 and 7.12 MeV) states of O¹⁶, were measured at five energies from 11.9 MeV to 15.6 MeV. Although angular distributions vary remarkably with the incident energy, integrated cross section decreases monotonically as incident energy increases. In particular, at E_p=15.6 MeV the total inelastic scattering cross section was roughly measured to be 240±40 mb. From this result and the reported results for other reaction cross sections, we may deduce that O¹⁶ nucleus is considerably transparent even for this rather high incident energy, where the mean free path of nucleon in nuclear matter has nearly the minimum value in usual nuclei.
The excitation function for the elastic scattering shows appreciably sharp resonances at energies, 7.2, 10.6 and 14.7 MeV, and its gross structure has a large scale resonance of a width about 4 MeV, at incident energy of about 13 MeV. It appears that this resonance is the f-wave giant resonance expected from the shell model.

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As the features of the high energy soft components of cosmic rays have not yet been thoroughly investigated, it is of greet interest to study them at present day, especially in very high energy region (above BeV). To obtain the energy of such high energy electron or photon, the electromagnetic shower theory can be applied.
Using an experimental arrangement consisting of GM-counter hodoscopes and an ionization chamber with large area, the pulse height distribution of cosmic-ray showers produced by electrons or photons in lead and iron absorbers of different thickness was measured. The number of shower particles was estimated from the pulse height considering the angular spread of shower particles, and the energy of electrons or photons was obtained from the results of shower theory. The results of the present experiment show that, i) the differential energy spectra can be represented by a power law of the form E^−γ, with γ of 2.90 and 2.80 for electrons and photons of 2–20 BeV, respectively, ii) the zenith angle distribution of electrons is expressed by cos²θ, and iii) upper limit of the ratio of the number of electrons to that of photons is 1.1. It is also found that the calculated results by Ivanenko are favorable to explain the observed results for lead and iron absorbers. The essential part of this investigation is to provide a classification of the incident electrons or photons by the GM-counter hodoscopes, that is, single incident particles, multiple incident ones, and those associated with EAS are separated in order to minimize the ambiguity involved in the results.

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Several A₄[M(CN)₆]·3H₂O type cyano-complexes belonging to the crystal class C_2h were studied to examine ferroelectricity. Isomorphous substances obtained through replacing the Fe⁺⁺ ion by Ru⁺⁺, Os⁺⁺ and Mn⁺⁺ ions show ferroelectric behavior below −14°C, −2.4°C and −40°C respectively. Ferroelectric behavior of these compounds are vary similar to that of the potassium ferrocyanide trihydrate, reported before. The potassium ferrocyanide group ferroelectrics has ferroelectric axis parallel to [10\bar1] direction. Ferroelectric transition of these substances is probably of the second order.

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A semi-classical theory is given for explaining the characteristics of the interaction of conduction electrons with acoustic waves in many-valley semiconductors such as n-Ge. In general, the ultrasonic absorption coefficient can be written as
Λ=Λ_P+Λ_K,
where Λ_P is due to the change of the deformation potential energy of electrons caused by net intervalley transitions. Λ_K due to the change of the kinetic energy caused by intravalley transitions. The acousto-electromotive force can be also written as
F=F_P+F_K.
In the low frequency range the dominant terms are Λ_P and F_P, but Λ_K and F_K Predominate in sufficiently high frequency range. For longitudinal waves propagating in the ⟨110⟩ direction and transverse waves propagating in the ⟨100⟩ direction and polarized in the ⟨010⟩ direction, F is identical with the formula of Weinreich-Sanders-White in the low frequency range. But in contrast to their formula, F does not decrease in the high frequency range owing to the increase of F_K and has the same order of magnitude as that for longitudinal waves in simple semiconductors. In special cases such as for longitudinal waves propagating in the ⟨100⟩ direction and transverse waves propagating in the ⟨110⟩ direction and polarized in the ⟨1\bar10⟩ direction, Λ_P=F_P=0 and then the interaction becomes essentially identical with that in simple semiconductors.

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A theoretical analysis and experimental evidence show that a source of energy for spontaneous whisker growth is the elastic strain energy arising from the anisotropy of thermal expansion. Observation of whisker growth on a Bragg bubble raft suggests that the growth mechanism could be by cooperative repetitive movement of dislocations. The conditions for whisker growth from the solid are presented and by fulfilling them growths were produced on gold, silver, bismuth, lead, indium, and lead-indium alloys. The crystallographic orientations of a number of tin whiskers are reported, one of which had a transition between two orientations although it was straight. The tensile strengths of several tin whiskers were measured and observed to be lower than calculated from bending tests. The high elastic strain of 5% in bending was observed for an indium one.

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A foundation of the Heitler-London approach to electrical conductivity is given, which has been left unproved in the previous paper (J. Phys. Soc. Japan 15 (1960) 802), applying Van Hove’s method. The hopping motion of electron is realized under the conditions: large effective mass, strong interaction with lattice and the presence of a potential fluctuation through lattice.

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The line widths of paramagnetic resonance absorption of Fe³⁺ ions in MgAl₂O₄ and ZnAl₂O₄ polycrystals and of Mn²⁺ ions in ZnAl₂O₄, having the same spinel crystal structure as ferrite, are measured as a function of concentration.
The cubic crystal field splitting parameters a of Fe³⁺ ion at A- and B-sites are determined from the line widths extrapolated to zero concentration: a_A=1.0×10⁻² cm⁻¹ and a_B=3.1×10⁻² cm⁻¹. a_B⁄a_A=3.1.
On the other hand, the magnitudes of exchange integral between Fe³⁺ ions in A- and B-sites or in B- and B-sites are estimated from the decrease of line width due to exchange narrowing as the concentration increases, namely, J_AB⁄gβ=1.32×10⁵ Oe and J_BB⁄gβ=1.90×10³ Oe. The Curie temperatures obtained from the exchange integral are in agreement with the Curie temperatures of Mg-ferrite and Zn-ferrite measured experimentally.

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A transistor was made with an imperfect emitter junction having an irregular structure made by applying a very thin indium layer on an n type germanium pellet and a comparatively perfect collector junction having regular structure. The current flowing into the imperfect emitter was divided into various components, and the voltage-current characteristics of each component was studied. Among these, a particular attention was paid on the electron current component which flows through the minute area of the m–n junction existing at the irregular part of the p–n junction. From these studies the phenomena of the voltage-current characteristics of the emitter differing greatly from the Shockly Equation, the abnormally strong current dependency of the current amplification factor of the transistor, and the floating-potential of the emitter are explained.

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By assuming that the mobility μ can be expanded in powers of the field strength F as μ=μ₀(1−νF²), ν is calculated for non-polar and polar semiconductors. The electron-electron interactions are neglected completely and the Boltzmann equation is solved by means of the variation method. It is shown that ν calculated in this way differs significantly from that calculated in the previous paper and in Stratton’s particularly at low temperatures. The electric field dependence of the Hall coefficient is also estimated.

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Twinning behaviour of tin was investigated as a function of temperature and strain rate. The resolved shear stress for twin became large and the scatter of individual values was pronounced, as the temperature was lowered and strain rate was increased. The observed twinning stress was not so large as to expand the stacking-fault across the crystal, but it was sufficient to trigger twin nucleus if local stress concentration was produced, say, by dislocation pile-ups. As the temperature was raised and strain rate was decreased, deformation by slip preceding twin became dominant, and twin formation was finally prohibited. The activation energy derived from the ductile-brittle transition temperatures is approximately that of self diffusion, suggesting that recovery due to dislocation climb releases local stress and prohibits twin nucleation. Hardening of twin boundary migration was found at low temperatures or at high strain rates, while the initial migration stress was not raised by these factors but raised by prestrain. It was about one order of magnitude smaller than that for twin initiation, and too small for the creation of twin dislocation ring on the existing twin layer. A mechanism of sweeping and climbing of the twin dislocation around a pole dislocation is necessary to explain the observedvalue.

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The ordered Au₄Mn alloy has been investigated by electron diffraction, using oriented, evaporated films. This ordered alloy has been found below about 400°C to have the body-centred tetragonal unit cell which is 2.5 times as large as the fundamental cell in volume. The structure is isomorphous to that of Ni₄Mo and belongs to the space group I4/m−C_4h⁵. This structure is not the so-called anti-phase domain structure. Some qualitative discussions have been given of the structural transition between the ordered Au₄Mn and Au₃Mn and of the origin of ferromagnetism in Au₄Mn, on the basis of the proposed structure model.

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A calculation of the cohesive energy of the diamond crystal has been carried out by using the general scheme which is derived by the Heitler-London approximation in the preceding article. It has been found that the value of the binding energy is about 3.26 eV per a bond in rather good agreement with the observed one.

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The magnetic susceptibilities and the g-values of the Pd and Pt group transition metal complexes are calculated by means of the intermediate coupling scheme. Crystalline field with cubic symmetry is assumed to be strong, so that the effect of dγ orbitals is neglected. The effect of Coulomb repulsion is considered to be comparable with that of the spin-orbit interaction. The results are expressed by functions of parameters η=ζ_d⁄(3B+C) and kT⁄ζ_d, where B and C are Racah’s parameters and ζ_d the coefficient of spin-orbit coupling of a d-electron. Comparison with available experimental data is also made.

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The potential barrier which hinders the internal rotation in ethyl iodide molecule was studied. If the potential energy is assumed to be of the sinusoidal form \fracH2(1−cos 3x), the barrier height is determined as H=3.22±0.5 kcal/mole from the Q^b-type transition in the first excited torsional state. The torsional frequency is about 230 cm⁻¹. The effect of internal rotation on the quadrupole hyperfine structure of K=1 levels was analyzed.

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It is concluded through proton magnetic resonance that the positions of protons in boric acid crystals lie considerably away from the lines connecting two hydrogen bonded oxygens, in contrast to the case in potassium bicarbonate crystals, where protons are approximately on the oxygen-oxygen lines. The result is discussed in connection with the difference in strength of the hydrogen bond both cases.

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Two new series of ΔJ=0 transitions in the first excited torsional state as well as one series of the S³⁴ isotopic molecule were found in the range up to 37 Gc/sec besides those reported in the previous paper. The two series in the first excited torsional state are discussed, confirming the potential barrier height V₃=443.9±1.0 cm⁻¹ which were determined from ΔJ=±1, ΔK=\mp1 lines in the ground torsional state. Moreover, the hindering potential is considered to be sinusoidal with an accuracy of better than one percent from those analyses.

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Generation of an acoustic wave and transformation of its energy into thermal energy are considered. We generate an acoustic wave, imposing an oscillating magnetic field to a cylindrical plasma in a static magnetic field. When the suitable frequency of oscillating field is chosen, an acoustic wave is excited at an intermediate state between adiabatic and isothermal states. In this situation acoustic energies are transformed into thermal energies through the irreversible flow of heat due to stress relaxation.
In this method, the efficiency of heating is very high. The calculation shows that this method should be suitable to heat a plasma of moderate temperature (10⁵∼10⁶ °K) and of high density (10¹⁴∼10¹⁶ particles/cm³).

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In a single crystal of KI/Tl, emissions from Tl⁺ ion and a certain impurity were observed under excitation of light in the first characteristic absorption band of KI. These exciton-induced luminescences were measured at various temperatures for specimens of several concentrations of Tl⁺ ion. The intensities of the exciton-induced luminescences attained saturated values at about liquid oxygen temperature. In consideration of the amount of energy transferred to the impurity, the saturated intensities of the exciton-induced luminescence from Tl⁺ ion are almost independent of the concentration of Tl⁺ ion in the range of 10¹⁵∼10¹⁹/cm³ and showed a quantum efficiency as high as 30%. Therefore the migration of an exciton through the crystal was confirmed.

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The dichroic properties of Z bands and their correlation to that of the F band have been studied on NaCi:Sr and KCl:Sr single crystals.
From the experiment on the anisotropic bleaching, the Z₁ center was found to be a center of high symmetry in agreement with the result of paramagnetic resonance experiment. The Z₂ band showed dichroism when irradiated with [010] polarized light in the Z₂ or F band at room temperature, accompanying the dichroism of opposite sign in the F band. This is another example of the correlation in dichroism between two absorption bands as shown in the F-M system which has been found by Van Doorn and Haven. It is, however, questionable to simply decide the symmetry of the Z₂ center from the dichroism mentioned above, because in the case of KCl:Sr its peak position is shifted to shorter wavelength than the normal Z₂ band.

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From the study of thermal bleaching of the F, M and R₂ bands in KCl crystals containing U centers, the behavior of the hydrogen molecules produced from U centers was examined. The hydrogen molecules do not react with F centers but with M centers by bimolecular reaction and make M centers convert to U centers.
Furthermore, thermal bleaching of the Z₁ and Z₂ bands in KCl crystals containing divalent cations was also investigated. The Z₁ and Z₂ bands are thermally unstable at temperature above 80°C, while they are stable up to 110°C and 250°C, respectively, in the crystal containing no U centers. From these results, in KCl:Sr crystals it is supposed that Z₁ centers do not return to U centers but form unknown centers by combining with the hydrogen molecules.

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This paper deals with the hydromagnetic flow of an electrically conducting fluid due to an oscillating flat plate of perfect conductor in the presence of transverse magnetic field. Exact solutions for arbitrary values of R (the Reynolds number), R_m (the magnetic Reynolds number) and S (the magnetic pressure number) are first derived and then some special cases are discussed corresponding to limiting values of the parameters S and R_m in order to clarify the hydromagnetic effect, and especially an interesting special case corresponding to the ‘magnetic Stokes approximation’ is discussed in some detail.
Next, the drag on the plate is calculated for both cases of non-conducting plate and perfectly conducting plate. It is found that, in both cases, the amplitudes of the total drag (shear-stress+Maxwell’s stress) always increase and the initial phases of the total drag are always retarded for any values of R, R_m and S compared with those of the well-known classical case, i.e., the case of no magnetic field and/or electrical conductivity of the fluid being zero.

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The present paper extends the classical results on two-dimensional stationary temperature distribution in an infinite plate to the case of a composite strip. General deductions are applied to some special cases leading partly to new results not given in the literature.

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Two theorems concerning circulation preserving motions have been stated and proved. Two particular examples to illustrate them are also given. It is deduced that two circulation preserving motions in a Newtonian fluid when their sum is circulation preserving are mutually super posable but in a non-Newtonian fluid this proposition is true only if one more condition is satisfied. Similar results have been deduced for self-superposability also.

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