By introducing an ‘internal’ orbital L, the mass spectra of nucleon family are accommodated into the two groups, each of them having the opposite ‘internal’ parity with each other and each manifesting the rotation spectrum character:
M²=L(L+1)a²+M₀²,
(α and M₀ are constants). For each of the L-values, the hypermultiplets characterized by the values of the hypercharge Y (Y=0, ±1, ±2) are introduced and compared with the experiments.

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The energetics of helium-ion-induced fission of U²³⁸ has been investigated, a back-to-back solid state detector system being used. The measurements have been made at two center-of-mass angles 90° and 160° and at bombarding energies of 27.8, 30.4, 32.6, 34.2 and 35.6 Mev. It Is found that the position of the asymmetric fission peak in the kinetic energy contour diagram and the most probable values of E_L, E_H and E_K are nearly independent of the excitation energy of compound nucleus. From the comparison with results obtained so far at lower energies, it is probably concluded that the average total kinetic energy in symmetric Fission increases with the excitation energy of fissioning nucleus but the one at the peak in the mass yield distribution is approximately independent of the excitation energy. Some systematics are derived for the average total kinetic energies. The average excitation energy of fragments remains nearly constant in symmetric fission but not in asymmetric fission as the excitation energy of fissioning nucleus increases. The anisotropies for symmetric and asymmetric fission are probably consistent with a theoretical prediction.

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By using x-ray films with different sensitivities, observations have been made on the lateral and longitudinal distributions of the energy loss in showers developing in lead. The x-ray films inserted among lead plates were irradiated by the electron beam with an energy of 200 MeV and by the bremsstrahlung gamma-ray beam with peak energies of 720 MeV and 200 MeV.
There seems to be some difference between Kantz and Hofstadter’s results and ours in the lateral and longitudinal distributions of the energy loss in the electron-initiated shower. This difference is discussed in some detail. The results are also compared with the conventional shower theory.
A fraction energy loss contained in various cylindrical volumes of lead is calculated from data obtained in the present experiment to facilitate a determination of the efficiency of a total absorption type detector.

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The response of a rarefied gas to abrupt change of temperature of bounding wall is discussed using the Bhatnager, Gross and Krook model of Boltzmann equation. The temperature change of the wall is assumed to be small and the governing equations as well as the boundary conditions are linearized. The density and temperature distributions in the gas are obtained for both short and long times. For short times the solution represents a perturbation to the linearized free molecular flow. At long times it involves essential differences from the corresponding solution based on the Navier-Stokes equation in a layer adjacent to the boundary with thickness of the order of mean free path. Numerical value of temperature jump distance is also obtained.

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The Hall coefficient and the mobility of p-type Ge were measured at 290°K and 195°K in the non-Ohmic or “hot electron” region by pulse technique. The Hall coefficient measured at 930 gauss decreased at much lower electric field compared with the case of the mobility. This was interpreted as the light hole mobility decreasing with increasing field more strongly than the heavy hole mobility. The data at 290°K were analyzed quantitatively on the assumption that the two types of holes have different temperatures.

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Constitution of iron-germanium system is discussed based on x-ray and magnetic studies, and a new phase diagram is proposed. Fe solid solution (α) ranges up to 20.4 at.% Ge at 710°C and to 21.3 at.% Ge at 520°C. Homogeneity range of the most iron rich compound (ε above 700°C and ε₁ below) are 23.8–26 at.% Ge at 710°C (ε) and 24.2–25.8 at.% Ge at 580°C (ε₁). At 50 at.% Ge, ξ phase has a narrow range below 700°C.
In α (b. c. c.) solid solution of iron, the saturation magnetization and Curie point decrease to 150 emu/g and 885°K respectively. Crystal structures of ε and ε₁ phases are Ni₃Sn (D0₁₉) and Cu₃Au (L1₂) type, and the saturation magnetization of both phases is about 150 emu/g, while the Curie points are 650°K for ε and 760°K for ε₁. ζ Phase has CoSn (B35) type of structure and is paramagnetic, the moment being 2.8μ_B/Fe. Magnetic interaction and magnetic structures are also discussed.

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The changes in a water-etched KCl single crystals due to weak electron irradiation were observed by means of an electron microscope and by electron diffraction. It was found that in a crystal, the thickness of which became large with the distance from the edge, dislocation loops appeared and their development as observable. When the change of the thickness of the crystal is pronounced, it was easy to find large dislocation loops in the thin part close to the edge of the crystal. In the case in which the size of a dislocation loop is less than 0.5 μ in diameter, one dislocation loop changed abruptly into one void with weak electron irradiation. However, a larger dislocation loop changed into one void and several small dislocation loops. Interactions between two crystal imperfections were also observed in this experiment. From the experimental results, the mechanism of coagulation or dispersion of vacancies in water-etched KCl crystals under weak electron irradiation is discussed.

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Some features of precipitation in an Al-8.5 wt.% Mg alloy were investigated by means of transmission electron microscopy. Needle-like (or rod-like) precipitates of various orientations and plate-like precipitates on both {100} and some planes deviated from {100} towards {130} were present in the specimens aged at 150°C and 200°C.
At an early stage of ageing, dislocation loops were observed around some small precipitates, which were formed by the annihilation of the excess quenched-in vacancies. During the growth of precipitates, a large number of dislocations were generated around the precipitates.
Some possible mechanisms of the dislocation generation in the last case were discussed, considering the nature of stress-field around the precipitates.
Also, some movements of dislocations during growth of precipitates were observed by heating the thin foils in the electron microscope. The distribution of dislocations observed in the aged bulk specimens can be explained from such movements of dislocations during ageing.

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Growth process of the BaTiO₃ butterfly twinned crystals was observed in the region of 1160 to 880°C by stopping the growth at different periods. The process seems to consist of two different ways, namely a relatively rapid two-dimensional growth above 1000°C and a slow thickening one throughout the crystal growth. On the other hand, growth process of the (Ba,Sr)TiO₃ butterfly crystals was also observed. The Sr content in the crystal lattice increased below 1000°C, where thickening growth is dominant. Thus the thickening growth of the butterfly crystals also shows different behaviors bounded at 1000°C. These two different growth behaviors probably originate from a large degree of supersaturation above 1000°C and a small one below 1000°C developing in the molten solution of KF-BaTiO₃. The explanations for the two growth behaviors seem reasonable referring the solubility data for the KF-BaTiO₃ system.

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The nuclear magnetic resonance (NMR) of Ni⁶¹ in Nickel-ferrite at zero external field has been observed at liquid air temperature by using the pulsed NMR method. The spin echo signal could be observed in the frequency range from 31 Mc/sec to 38 Mc/sec. The center frequency (34.5 Mc/sec) corresponds to the value of about 97 KOe of hyperfine field, which could be accounted for as the sum of the core polarized and the orbital hyperfine fields of Ni²⁺ ion. This value is consistent with the hyperfine coupling constant of paramagnetic Ni²⁺ ion diluted in Al₂O₃.

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The Mössbauer effect has been studied in the 100-keV (2⁺→0⁺) transition in W¹⁸². Metallic tantalum was used as the source and metallic tungsten, powder of WO₃ and single crystal of WO₃ as the absorbers.
For the absorbers of powder of WO₃ and single crystal quadrupole interaction was observed. The value of eQV_zz (1−R_A)=−3.5×10⁻⁶ eV was obtained. The electric field gradient at the nucleus of tungsten in the lattice of WO₃ Was estimated to be 1.7×10¹⁸ Volt/cm² and the asymmetric parameter η was proved to be approximately zero

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A method is described for determining the height of the potential barrier for hindered rotation in a molecular crystal, in which the intensity of infrared absorption band is measured for different angles of polarization as a function of temperature. The barrier height is obtained from an average value of temperatures at which the “intensity versus temperature” curves intersect. Further, an empirical relationship is given between the potential barriers and frequencies of hindered rotation in various compounds, which is well approximated by
V=0.64−0.016·10⁻²ν+0.31·10⁻⁴ν²±0.27,
where V denotes the former in Kcal/mole and ν the latter in cm⁻¹.

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