An investigation of the decay scheme of K⁴⁴ has been made with anthracene- and 5″×5″ NaI(Tl)-scintillation counters, and coincidence techniques. In addition to the 4.91-, 3.55- and 2.63-MeV beta rays, the following gamma rays has been assigned to Ca⁴⁴: 0.48-, 0.63-, 0.74-, 0.90-, 1.06-, 1.16-, 1.5-, 1.74-, 2.08-, 2.17-, 3.4-, 4.4-, 4.6- and 5.0-MeV. A decay scheme is proposed.

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The cross section of the reaction Cu⁶³(γ, n)Cu⁶² for Li gamma rays was measured in order to discover some causes of the existing discrepancy between values measured by bremsstrahlungs and by nuclear gamma rays. Experimental procedures used in this experiment were much improved as compared with those used in previous measurements performed in our laboratory for the same purpose.
The present results were as follows:
σ_Li−γ=62±4 mb for Li gamma rays,
and
σ_17.6=76±5 mb for 17.6 Mev γ-rays.
This value is about 30 per cent lower than the average cross section value determined by the photon difference method in several bremsstrahlungs’ experiments. Therefore, we suggest that the modified spectrum method proposed by Penfold and Leiss might eliminate not only the above-mentioned discrepancy but also the discrepancy between theoretical and experimental values in the form σ₋₂≡∫σE⁻²dE, as pointed out by Levinger.

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The stability of several cubic molecular crystals is investigated on the basis of multipole interaction between the molecules. The stability of the cubic close-packed structure of heavy rare-gas crystals is due to the repulsion between electrical octapoles induced in atoms in the hexagonal close-packed structure. The face-centered cubic structures of carbon dioxide and cyclohexane-hexahalides and the body-centered cubic structures of silicon-tetrafluoride and hexamethylene-tetramine are configurations with the maximum electrostatic attraction between permanent charge distributions in the molecules. Pingpong balls containing two or four pieces of magnet represent these molecules with permanent multipoles; and it is demonstrated that a proper “crystal” of such balls (suspended in water) is stable.

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Precise measurements of Hall effect have been made at 77°K, 90°K, 195°K, and 298°K up to 11,000 gauss on oriented single crystals of n-type germanium containing 5×10¹⁴ antimony per cm³ as donor centers. The results should principally indicate the variations of μ_H⁄μ with the magnetic field and with the temperature, since the carrier concentration may be practically constant under the present conditions.
Absolute values of μ_H⁄μ have been deduced from R_∞ and R₀. R_∞ for which μ_H⁄μ always equals unity is fortunately obtained by extraporating R_H^⟨001⟩ (77°K) vs 1⁄H² data. Then R_H^⟨001⟩⁄R_∞ will straightway give μ_H⁄μ·⟨001⟩_H. On the other hand, μ_H⁄μ for other orientations may be indirectly estimated from their extraporated R₀ for which μ_H⁄μ is independent of the orientation and should be equal to R₀^⟨001⟩⁄R_∞ at respective temperatures, neglecting the effect due to slightly different impurity concentration between specimens.
Values of μ_H⁄μ thus determined are always smaller than unity, while those of ⟨001⟩_H approach to unity most rapidly with increasing field and those of ⟨110⟩_H most slowly. They are of course temperature dependent and the zero magnetic field values are equal to 0.83 at 77°K, 0.84 at 90°K, 0.90 at 195°K and 0.92 at 298°K respectively.
Numerical evaluation of the Boltzmann’s equation taking account of ellipsoid model and mixed scatterings can give the observed values fairly well. It appears, however, preferable to introduce some correction term, e.g., reasonable amount of optical phonon scattering for the best agreement.

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The electrical and optical properties were measured with p-type synthetic CdTe single crystals. The Hell coefficients of the crystals increased by the heat treatment or the growth in the cadmium vapor. From the present measurements it will be shown that the intrinsic energy gap is about 1.43 e.v., the ionization energy of acceptors is about 0.20 e.v. and the Hall mobility of holes is about 80 cm²/volt-sec. at room temperature. It seems that the data of Hall mobilities are in agreement with the theory of intercation with the optical mode of lattice vibrations.

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The Hall coefficients of magnesium-cadmium alloys have been measured as a function of composition at both room temperature and 300°C with the magnetic field up to 6.5 KG. For all the compositions, the Hall coefficients are independent of magnetic field. An electronic structure of this system has been discussed with results of the lattice-spacing relations obtained by Hume-Rothery and Raynor. A relation between energy gap and concentration is discussed by comparing their results with the Hall coefficients measured by us. The present experimental results indicate that the energy gaps show a tendency to increase with the addition of cadmium to magnesium.

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The thermoelectric power Q associated with the movement of silver ions in Ag₂X (X=S, Se, Te) is discussed, where Q is obtainable by measuring the potential difference between silver electrodes in an arrangement as Ag(T₁)|AgI(T₁)|Ag₂X|AgI(T₂)|Ag(T₂). When a temperature gradient is applied, Q, in general, changes with time because of the thermal diffusion of both electrons and silver ions, and then reaches its steady value. An information on the heat of transport of a silver ion is obtained from the comparison between theory and experiment.
An explanation on the heat of transport in ionic crystals is given taking into account the variation of vibration frequency of lattice due to the presence of defects. The theory is compared with the experimental data on silver halides and Ag₂X available at present.

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Horner et al’s method of dielectric measurement at microwave region has been extended so that it can be applied for cylindrical specimens of arbitrary cross-sections with relatively high loss tangent and high permittivity. Small amount of Specimen is good enough for our method. As the first application of our method, dielectric constants of BaTiO₃ single crystal have been measured from room temperature to 170°C at a frequency of 3.3KMc/s. Above the Curie point, dielectric constants measured at 3.3KMc/s agree well with those measured at 24KMc/s by Benedict and Durand, while the loss tangents slightly above the Curie point are 0.01±0.007 in our case compared to 0.1 in the case of Benedict and Durand.

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We have calculated the electrical resistance of dilute paramagnetic alloys from the standpoint of seeing if the resistance minimum could arise from the short range order of the spins of the solute atoms.

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Thin foils have been made by electrolytic polishing from bulk specimens of cold-worked high manganese steel. They have been observed by electron microscopy with the object of studying lattice defects formed by cold-working. From the micrographs and the selected area electron diffraction patterns obtained it is concluded that on {111} planes of the austenite matrix very thin (<100Å) plates of a hexagonal close-packed phase (ε) are formed, which correspond to the origins of strain markings formerly found on the etched surface by using the replica, and that ordinary stacking faults as found in 18–8 stainless steels are also present.

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Using the far-infrared spectrometer constructed recently in Osaka University, measurements of the optical absorption were made on the single crystal of NiO (Néel temperature=523°K) in the wave-length range of 210 to 385 microns and at temperatures 90° to 470°K. No magnetic field was applied. An absorption peak was clearly observed whose wave-length varied with temperature. With increasing temperature it shifted toward the longer wave-length side and at the same time the peak height diminished. At room temperature (291°K) the peak was at 293±5 microns (34.1±0.6 cm⁻¹) and the wave-length value extrapolated to absolute zero was 274 microns (36.5 cm⁻¹). This absorption peak is attributed to the antiferromagnetic resonance of the mode in which the antiparallel sublattice magnetizations oscillate perpendicularly to the easy plane of magnetization, (111). The constant, K, of the anisotropy energy which constrains the sublattice magnetizations in the easy plane is calculated to be 4.96×10⁶ erg/cc at 0°K from the theoretical formula ω=(ge⁄2mc)(2K⁄χ_⊥)^1⁄2, assuming g=2.23. This can be compared with theoretical value, 7.01×10⁶ erg/cc, based on the magnetic dipolar interaction between Ni⁺⁺ ions, but the experimental value is smaller.

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Magnetostriction constants, λ₁₀₀ and λ₁₁₁, of nickel-chromium and nickel-vanadium alloys were measured at room and liquid nitrogen temperatures by a strain gauge method. Both constants were negative and their magnitudes decreased monotonically with increasing the composition of adding elements. Magnetocrystalline anisotropy constants were also measured at the same temperatures. The concentration dependence of the anisotropy constants was more drastic than that of the magnetostriction constants.
The present data and other available data of nickel binary alloys were analysed on the basis of Néel’s theory and the coefficients of dipole-dipole and quadrupole-quadrupole interactions of atom pairs in nickel alloys were estimated. The dipole-dipole interactions of Ni–M (where M=V, Cr, Mn, Fe, Co, Ni and Cu) atom pairs were fairly well explained under the assumption of the spin-orbit interaction.

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Systematic studies were made on the preparation of pure KCl and NaCl crystals. Effects of the starting material on the purity of crystal were studied with KCl and NaCl powders of reagent grade of several different brands and with those prepared from bicarbonate and hydrochloric acid. Methods by distillation and crystallization in vacuum and by Kyropoulos technique in air were used for the crystallization procedures to study on each of their advantages. To estimate the concentration of impurities in crystals, the measurement of ionic conductivity was made for multivalent metallic ions, optical absorption for hydroxyl ions, and chemical analysis for bromine ions. The purest crystal in respect of these impurities was found to be the one grown from its powder prepared from bicarbonate and hydrochloric acid by the method of distillation and crystallization in vacuum. After the studies on the edge of the fundamental absorption in connection with the concentration of bromine, an absorption band due to the presence of bromine was found in KCl of which maximum is at 7.12 ev at room temperature.

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The anisotropy of a ferromagnetic single crystal of CrTe with NiAs structure was investigated by magnetic torque measurements. From the experiment it was seen that the axis of easy magnetization is [001] and it does not change from room temperature to liq. He temperature. At 0°K the uniaxial anisotropy constant will be about 5×10⁶ erg per cm³. As for the origin of anisotropy, the dipole-dipole energy can account for only about 20 percent of the observed value.

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The neutron total cross sections of carbon, oxygen, fluorine and thorium have been measured in the energy range of 3.3 to 5.0 MeV. Measurements were made with a good-geometry arrangement and an energy resolution of about 20 keV, using a neutron detector which had a high efficiency and a good characteristic for gamma-ray discrimination. For carbon, oxygen and fluorine, several resonances in the cross sections were analyzed to give spin assignments. For thorium, a giant resonance was observed at 4.2±0.2 MeV.

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The temperature dependence of the surface potential of silver chloride single crystals is similar to that of silver bromide single crystals. The knee point moves to the higher temperature as the content of cadmium in the specimen is increased. The formation energy of Frenkel defect and other quantities are obtained. Comparing with the results of ionic conductivity measurements, the intrinsic and the structure-sensitive regions of silver chloride single crystal determined by surface potential were found to correspond to those determined by ionic conductivity, respectively. From the difference between the reciprocals of the knee point temperatures determined by the two methods, the ratio of the mobility of an interstitial silver ion to a silver vacancy may be obtained.

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The thermomagnetic properties of the compound Cr₂As and Cu₂Sb were investigated together with the phase diagram of Cr–As system. From the results of thermal and thermomagnetic measurements for Cr₂As and Cu₂Sb it was found that they show antiferromagnetic behavior with the Néel point at 393°K and at 373°K respectively. Their reciprocal susceptibilities obey the Curie-Weiss law in high temperature range, but a considerable deviation therefrom is seen just above the Néel point. From the Curie constant obtained by the present experiment, the effective magneton number μ_eff of the magetic carrier was calculated to be 3.6 and 2.6 for these compounds, Cr₂As and Cu₂Sb, respectively. The total heat absorptions due to the vanishing of antiferromagnetic order in spin arrangement were 50 Cal/mol and 20 Cal/mol. A discussion is given on the origin of the above-mentioned magnetic properties.

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The variation of the lattice dimension of the solid solution system, NiFe₂O₄–Fe₂O₃, and the precipitation process of α–Fe₂O₃ therefrom were investigated by X-ray analysis. These quenched solid solutions possess unstable inhomogeneities originating in the localized oxidization. When annealed at certain temperatures, the solid solution tends to become stabilized by the precipitation of α–Fe₂O₃. The activation energy for the precipitation was found to be ca 1.03 ev.
The solubility of Fe₂O₃ in NiFe₂O₄ was determined at various temperatures, and the heat of dissolution was found to be 1.3 ev.

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Crystallographical properties of the chemically prepared powder samples of Ag₂O and Cu₂O were investigated by an X-ray diffractometer, in relation to their bonding characters. The lattice constant is 4.720±0.004A for Ag₂O and 4.268±0.001A for Cu₂O. The thermal expansion coefficient of the lattice is 1.9×10⁻⁶ for Cu₂O. The root-mean-square amplitude of the thermal lattice vibration is determined as 0.26A for Cu₂O and 0.40A for Ag₂O at room temperature. The mean lattice strain is 1.4% for Ag₂O and 0.15% for Cu₂O, respectively. The thermal decomposition of Ag₂O was also observed. The obtained results suggest that the binding force between metallic and oxygen atoms is much weaker in Ag₂O than in Cu₂O, which can not be expected from the purely ionic model for the present crystals.

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In electron micrographs of molybdenite films, various network-patterns were observed. They are interpreted as images of dislocation networks. Several electron micrographs are reproduced and remarkable features observed in them are explained in terms of dislocations. One of the remarkable observations is that each line of a network sometimes becomes broader and the network changes into a moiré pattern. The gradual change from a sharp image of dislocation to a broad moiré fringe can be explained by a simple consideration. The former implies that the strain accompanying the dislocation is concentrated and the latter, that the strain is spread.

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Beam-type masers for radiofrequency spectroscopy of molecules are considered. The theoretical estimate of sensitivity is discussed and a table of minimum detectable beam intensity and estimate of available beam intensity for some of the low frequency transitions is given. A K-type doubling transition, 4₃₁→4₃₂, of formaldehyde was observed as an emission line at 4.5769±0.0023 Mc, and compared with theories. The observed saturation in focusing is probably due to the non-adiabatic change of rotational states in the focuser. The saturation broadening of the line with increasing rf field shows agreement with theory.

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The paramagnetic susceptibility of Sm³⁺ ion measured by Borovik-Romanov and Kreines are explained on the basis of crystalline field theory. Postulatiug an appropriate cubic or trigonal potential for two modifications of Sm₂O₃, the magnetic behaviours are well explained with the best choice of the coefficients of each potential. Total separations of the ground manifold 216k and 432k are obtained for the two cases and are compared with the above author’s rough estimations 52 cm⁻¹ and 150 cm⁻¹. Further, their erroneous assignment for the lowest state is pointed out.

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Lehmann’s experimental results on the emission intensity of a single electroluminescent phosphor particle embedded in an insulating dielectric as a function of the applied voltage are analysed on the model proposed in the Part I of this report. In this model the local field enhancement is attributed to the disturbance of the applied field due to the conducting phase of the phosphor particle. The results are reasonable and the validity of the model is confirmed.

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The pseudokinematical theory of electron diffraction is considered to be a good approximation for gas molecules. When, the theory is applied to crystals, however, there is an ambiguity concerning the nature of the approximation. In the present paper, the ambiguity is removed by comparing the result of the theory with the exact solution. The higher order Born approximation applied to the entire crystal is used as the exact solution. It is concluded that the pseudokinematical approximation is better than that of the usual kinematical theory and coincides almost with the exact solution under the condition that the crystal is very thin and there is no overlap of atoms when the crystal is seen from the direction of the incident beam.

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Evidence of antiferromagnetism in perovskite-type potassium iron group fluoride KMF₃ was found through the susceptibility measurements made between 80°K and 700°K. The obtained results are as follows:
(Remark: Graphics omitted.)
Additional thermal analysis was also made in order to confirm the Néel points. The magnetic properties of these compounds are reviewed and brief discussions of our results are given.

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A general method is presented for estimating the effect caused by a small change in the boundary shape (or the hypersurface shape in the many-dimensional space, the time-coordinate being included) upon the solutions or eigenvalues of linear partial differential equations (elliptic, parabolic or hyperbolic). When the given boundary is slightly deformed from a shape favorable for obtaining the solutions, this method gives the approximate solutions or eigenvalues based upon the exact or unperturbed ones for the case of the favorable shape, where many solutions can be obtained easier. The following illustrative examples are given, showing the validity of the method presented: (1) The eigenfrequencies of the lateral vibration of a uniform membrane fixed at its boundary close to a circle in shape, e.g. elliptic, oval, cinquefoil-shaped, etc. (2) The eigenvalue problem concerning the heat conduction of a “corned-beef-can” -shaped uniform matter, close to a rectangular parallelepiped in shape and with its temperature being kept constant on the boundary surface. (3) Three boundary-value problems representing the parabolic, hyperbolic and elliptic cases, respectively.

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Transonic flow past an infinitely long sinusoidal wall has not hitherto been thoroughly investigated, although some studies of the high subsonic flow near the critical have been made by Kaplan and others by use of the thin-wing-expansion method and the transonic approximation method. In this paper the author studied transonic flows past a sinusoidal wall including shock waves by use of his new method, and could find the velocity and pressure distributions on the wall with success. The result gives a reasonable model for understanding the transition of the flow pattern from subsonic to supersonic.

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The ignition mechanism of hydrocarbon-air mixtures is discussed. Thus, the ignition probabilities of various hydrocarbon-air mixtures were computed from the fluctuations of their ignition lags in shock waves. From these ignition probabilities, the activation energies of the primary and secondary reactions were calculated.
Next, the activation energies for the C–H and C–C bonds in the reaction with oxygen are estimated, as well as the amount of heat liberated for secondary reactions.
The mean ignition lags of other n-paraffin-air mixtures were, in accord with the experimental conditions, estimated from the above determined values.

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Using a Beckman & Whitley high-speed framing camera, the velocity of glass fracture caused by an underwater disruptive electric spark was measured. The observed maximum velocity was about 2.4 km/sec, 60% higher than the usually accepted normal limiting value. A gradual decrease of fracture velocity was also observed. From these observations it has been deduced that the maximum fracture velocity is, contrary to the hitherto assumed theory, dependent on the increasing rate of applied stress.

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