The directional correlations of the 300 KeV–300 KeV, 468 KeV–316 KeV and 300 KeV–600 KeV gamma-gamma cascades in Pt¹⁹² have been measured by using the coincidence spectrometer reported previously. It is found that the spins of the 784 KeV and 920 KeV levels are 4 and 3, respectively.

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A small scale beta ray spectrometer was built, making use of the double focusing principle applied to sector-field. The fringing field was found to be easily corrected and not to be serious for conventional purposes. The gathering power of 0.3% was obtained for the resolving power of 0.7%. Since the source can be placed outside of the magnetic field, this type of spectrometer might serve as a powerful tool for coincidence and correlation measurements.

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A twin setting of two sector type double focusing beta ray spectrometers was used for measurement of the weak higher component of Cs¹³⁷ in order to remove completely the contributions resulting from the secondary causes. The measured spectrum agreed well with those of the previous results, which were therefore confirmed to provide a reliable basis for the analysis of the coupling constants in beta decay.

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With the object of obtaining some basis for the thermodynamical consideration of the martensite formation, the temperature distribution during the transformation has been calculated using Bunshah and Mehl’s data for the speed of propagation of the transformation front. From the results of calculation it is concluded that (1) the nucleation may be treated as isothermal and that (2) the growth may also be treated in the same way if the propagation of the transformation is steady, but the treatment must be nearly adiabatic if the propagation is intermittent and its unit is large.

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A theory of the thermoelectric power in AgBr is developed, in which the experimental conditions are properly considered. The gradient of the electrochemical potential of silver ions is calculated, since it is related to the quantity measured by the potentiometer, that is, the difference between the Fermi levels at two free ends of lead wires. An expression for the thermoelectric power is derived, which is applicable to AgBr mixed with CdBr₂ at arbitrary temperatures.
The Peltier and Thomson coefficients in the steady state are independently calculated for this special case, and the result shows that the Kelvin relations are really statisfied in the steady state.
Finally, the theory is compared with the experiments of Patrick and Lawson.

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The phenomena of impurity conduction of semiconductors such as G_e and S_i are treated theoretically by deviding into the following three ranges of impurity concentration: (i) The concentration of impurity atom is fairly large and the impurity levels are merged into the conduction bands. Then the impurity atoms play a role of scatterers. (ii) The concentration of impurity atom becomes fairly small and the impurity levels split from the conduction bands. The energy width of this impurity band is, however, determined mainly by the translational energy of electron in this band. (iii) The concentration of impurity atom becomes very small and the width of the impurity band is determined mainly by the fluctuation of the local potential energy. In this paper we treat the first two cases. For this purpose, the general theory of transport phenomena is developped and the condition that the ordinary Boltzman—Bloch equation is applicable is given on this general theory. The result of impurity conduction given by E. M. Conwell is obtained as a limiting case of our formula. However the condition that the Conwell’s formula is applicable is not satisfied in actual cases.

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Solid solutions of ilmenite (MgTiO₃, MnTiO₃, FeTiO₃, CoTiO₃ and NiTiO₃) and hematite (αFe₂O₃) were prepared and their crystal structure was investigated by an X-ray analysis. It was confirmed that the solid solutions could be classified into three groups: 1) The specimens of ilmenite side and hematite side in the solid solution have the different crystal symmetries; R\bar3 and R\bar3c respectively and there exists a miscibility gap between them (MnTiO₃, MgTiO₃ and CoTiO₃ series). 2) Ilmenite and hematite make the solid solution in the whole range of composition and the crystal symmetry changes from R\bar3 to R\bar3c continuously (NiTiO₃ series). 3) The ranges of the crystal symmetries R\bar3 and R\bar3c of the solid solution are overlapped with each other and a transformation from R\bar3 to R\bar3c is observed in one specimen of the overlapped range (FeTiO₃ series). Such differences among different ilmenite and hematite systems may be attributed to the following three factors; differences in ionic radii, in electronic conductivity and in stability of other two solid solution series with spinel and pseudobrookite structures which exist in a ternary system of MeO-Fe₂O₃-TiO₂.

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As the basis of the calculation on formation energies of lattice defects, phenomenological expressions of interionic potentials are derived. In zincblende crystal which is partly ionic and partly covalent, the effective charge on the constituent ions is reduced to a certain amount Ze (Z=1.66, e: magnitude of the electronic charge), whereas covalent attraction between two ions adjacent to each other is generated, which is assumed to be exponential form −b_cexp (−r⁄ρc) such as the usual expression of exchange repulsion. As a preliminary calculation to Part II, the lattice energy variation when one anion or cation is displaced from its regular position in a perfect crystal is calculated on taking account of the Madelung, Van der Waals, exchange repulsion, covalency attraction energies and the polarization energies of the displaced ion and all other surrounding ions. All the physical constants already known in references and derived in our calculation are tabulated in Table III.

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The formation energies of various types of lattice defects in zincblende are calculated by means of Mott-Littleton’s method. A phenomenological expression of interionic potential which contains the covalency binding energy is used in the calculation. In addition, the total energy when the lattice around a defect is not in equilibrium is computed at several positions of the surrounding ions of the defect near the equilibrium point. The results of calculation show that the formation energies of Schottky defect, double hole and Frenkel defect by zinc ion are estimated to be 4∼6 eV. The result that the formation energy of Schottky defect is nearly equal to that of double hole is qualitatively in agreement with the experimental results which have been obtained with pure host crystal of ZnS phosphor.

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Internal friction of single crystal of lead (99.99% pure) was measured with longitudinal vibration in kilocycle range using the composite piezoelectric quartz oscillator. The dependences of the internal friction on the strain amplitude (0.5–12×10⁻⁶), on the frequency (64, 192 kc/sec) of vibration, and on temperature (140–340°K) were mainly studied. The internal friction is of the order of 10⁻³ at low temperatures, and increases slightly as the temperature is raised, and increases also with increasing strain amplitude. Near the room temperature, the value of the internal friction rises steeply. A peculiar temperature (about 300°K) has been found above which the internal friction decreases with increasing amplitude. The amplitude-dependent internal friction does not depend on the frequency of vibration and the amplitude-independent one seems to be proportional to the frequency.

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Intensity distribution of electrons scattered by carbon films was measured by the photographic method using a sector camera. The absolute intensity was obtained by the use of an intensity scale. The angular range of the measurement was 1.0×10⁻²∼1.2×10⁻¹ rad., the thickness of films 350∼4,400Å and the accelerating voltage 47 kv. Results of the measurement were in fair agreement with the theory of Lenz (Z. Naturforschg. 9a (1954), 185). For the detailed agreement, however, we must take a smaller atomic radius than that of Lenz and we must take into account the inter-atomic interference effect.

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The crystal structure of germanium selenide has been analysed by X-ray method. The structure is orthorhombic with the space group D_2h¹⁶- Pcmn. The dimensions of the unit cell containing four chemical units, GeSe, are a=4.38, b=3.82 and c=10.79 Å. It follows from the positions of all atoms determined by means of the electron-density projection that the structure is of a distorted NaCl type isomorphous with SnS and SnSe. The distances Ge–Se are 2.54, 2.58, 3.30 and 3.39 Å.

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Using plastically deformed crystals of KI, the nuclear magnetic resonance of I¹²⁷ has been observed. The broadened signals of I¹²⁷ show distinct anisotropy as regards the direction of the external magnetic field. This anisotropy is interpreted to arise from the definite orientation of a crystal dislocation. The experimental results are analyzed in terms of the gradient-elastic tensor which has been introduced by Shulman-Wyluda-Anderson. It is concluded that densities of edge and screw dislocations are fairly well balanced and increase for a certain range almost linearly with degree of cold-working, in agreement with the previously reported result for KBr. Assuming the total dislocation density to be 10⁹ cm⁻² for ten percent deformation, we get |C₄₄|∼8×10⁴ statvolts/dyne and its one-third for |C₁₁|. Comparison with the result for KBr shows that the amplification factor of eQq is greater than 50 for I¹²⁷ in KI.

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A differential equation which determines the time dependence of the radial distribution function of polymer molecules in dilute solution is derived. The equation is represented in a form of a diffusion equation.
For a case in which the solution is flowing with the constant velocity gradient, and the system is at a steady state, a calculation is carried out, adopting a Gaussian intermolecular potential between free draining chain polymer molecules. The result shows that the velocity gradient in solution causes the radial distribution function to be deformed into a non-spherical symmetry, and this deformation is increased with the increase of the velocity gradient and the molecular weight of polymer.

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The paramagnetic resonance spectrum of Mn⁺⁺ ions contained in NaCl single crystal with concentrations of 1∼3×10⁻⁴ in mole fraction has been investigated. From the analysis of the spectrum the existence of Mn⁺⁺ –Na⁺ vacancy complex, in which a Na⁺ vacancy is at one of the nearest neighbor positions with respect to the Mn⁺⁺ ion, has been verified at room temperature in crystals quenched from high temperatures. However, this state of Mn⁺⁺ ion is unstable at room temperature, and such complexes diffuse through the lattice to form aggregates of Mn⁺⁺ ions. The ground level splitting parameters of a Mn⁺⁺ ion accompanying a Na⁺ vacancy at one of its nearest neighbor positions have been obtained as follows: D=137.9±1 gauss, E=51.4±0.4 gauss, where D and E represent the parameters in the spin Hamiltonian, D[S_z²–1⁄3·S(S+1)]+E(S_x²–S_y²), in which z axis is in the direction of Mn⁺⁺ –Na⁺ vacancy and y axis along the cubic axis perpendicular to it.

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Chemical shift and line width were measured for the nuclear magnetic resonance of iodine nuclei in aqueous solutions of alkali iodides. The chemical shift was independent of temperature, but was dependent on the concentration of the solution. The spin lattice relaxation time calculated from the line width varied with temperature as well as concentration. General trend of the variation of the spin lattice relaxation time agrees with that of viscosity. By analysing the data of the chemical shift and spin lattice relaxation time, it is suggested that even in very dilute solution there exists chemical shift of the order of 6×10⁻⁴ as compared to the case of ‘pure ion’.

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To treat the problem of phosphorescence of alternant hydrocarbon we propose a new method to take account of the mixing of higher order AO’s.
We give here a theoretical scheme of the modification of 2pπ MO with the addition of 3d AO’s for diphenyl molecule. With the modified MO’s thus obtained, the singlet triplet intercombination matrix is given in the concrete form.

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The Mulliken and the Sklar approximations for difficult molecular integrals have for some years been the subject of several investigations. So far, however, we are not provided with clear insight into these approximate methods and, accordingly, with sufficiently reliable criteria for the choice between them for each individual case.
In this paper a possible answer to the problem is presented by examining carefully the accuracies of these two methods. In addition, a new approximate method is proposed, which is useful when both the Mulliken and the Sklar approximations break down seriously.

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A statistical mechanical theory of the so-called Weissenberg effect (or, normal stress effect) is presented. We adopt the weakly coupled rubber-like network model which we have formulated and applied to investigate the shearing and the tensile viscosity of concentrated solutions of linear high polymers. When the elastico-viscous liquid is compelled to stationary shearing flow, our theory shows that an additional normal tension arises in the direction of flow owing to the orientation of the network structure in addition to the usual shearing stress. Furthermore if the fluid is in a concentric circular motion with the angular velocity gradient in the radial or the axial direction, each doughnut-shaped piece along a flow line behaves as a streched rubber loop due to the said additional tension. As the result the inner bulk of the liquid is squeezed. The pressure increases as one approaches to the rotational axis. Such pressure distribution is calculated for the instruments of three types, i.e., the coaxial cylinder, the parallel plate and cone and plate instrument. The results are at least qualitatively in good agreement with various experimental results reported by Roberts, Philippoff, Rivlin, Kurata, Kotaka and Tamura and others.

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This paper is concerned with disturbance phenomena occuring when a probe is immersed in plasma.
There are two types of disturbance, i.e., one independent of probe potential and one which depends upon it. The former (inherent) disturbance has three effects which are classified: Asymmetrical effect, formation effect of transition region, and the scattering effect. The latter (incidental) depends on either the negative probe or the positive probe. In the negative probe, penetration of ion sheath into surrounding plasma is characteristic. In the positive probe, there is an unexpected change of electron current, as a result of drainage of electron, which is observed with rise of positive probe voltage.
The mechanism of collection of ion and electron on probe is also explained in terms of these disturbance effects.

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An attempt to improve theories of magneto-hydrodynamic oscillations of a conducting fluid sphere in a uniform magnetic field is made. Unlike the previous theories which have been developed by M. Schwarzschild and T. Rikitake, analytical expressions for zonal oscillations are obtained rigorously in this paper. It turns out that no eigen-periods are determined accurately. However, they are approximately obtained with drastic simplifications. Two fundamental normal modes of oscillation are also approximately obtained and illustrated.

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1032   Last line of Eq. (4),2(1+S_ab²)^−1⁄2 should be {2(1+S_ab²)}^−1⁄2.
1033   Line 8 in right column, xy should be yz.
1033   Eq. (16), (1/2a) should be inserted after (π/2a).
1034   Line 3, 2r·A and 2r·B should be 2r·A and 2r·B respectively.
1034   Line 6, K′=t(a+b+t) should be K′=t⁄(a+b+t).
1034   Eq. (21), the denominator of the first term should be (a+b) instead of (2+b).
1034   Line 30, (∂I₂″∂δ_a) should be (∂I₂′⁄∂δ_a).
1034   Eq. (27), exp {K′(ar_a²+br_b²)} should be exp {−K′(ar_a²+br_b²)}.
1035   Line 34, 2.332 Å should be 2.232 Å.
1035   Fig. 2, in legend, following sentence should be added: Upper curve is for 2–D and lower curve for 3–D.
1035   Fig. 3, the figures for maximum electron densities should be (a) 0.86, 0.76, 0.61 instead of 8.6, 7.6, 6.1, and (b) 0.86, 0.80, 0.66 instead of 8.6, 8.0, 6.6.
1036   Lines 5 and 3 from the bottom, Å should be Ų.
1037   Line 18 in left column, at should be as.
1037   References 3) and 7), Weatley should be Wheatley.
1037   Reference 5), S. Sasada should be Y. Sasada.

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The following line should be inserted after ‘connected to’ on line 5: ‘a voltage amplifier whose output terminals were connected to’.

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