Range distribution of high energy muons are calculated by a numerical method taking the fluctuation in energy loss by radiation and direct electron pair production into account.
With the obtained distribution, effect of the range fluctuation on the depth-intensity relation of cosmic ray muons is studied and compared with other similar works.

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Excess Volumes and Excess Adiabatic Compressibilities have been evaluated from density and ultrasonic velocity measurements in binary liquid mixtures of toluene, o. xylene, m. xylene and p. xylene with dioxan as a common component. Modern theories of interactions of the components of liquid mixtures have been examined and compared with the experimental results for excess volume. The nature of the sound velocity-molefraction curves has been explained on the basis of ‘available’ volume and intermolecular free length in liquid mixtures.

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The thermal conductivity of superconducting and normal f. c. c. lanthanum was measured at the temperature range 1.7 to 7.0°K. The thermal conductivity of yttrium was also measured to test the cryostat. The ratio of the energy gap of lanthanum at absolute zero to the transition temperature, 2Δ(0)⁄kT_c, is 2.9 to 3.0, where T_c=6.04°K. The ratio obtained from the temperature dependence of the thermal conductivity in the superconducting state is in agreement with the value deduced from the ratio of the thermal conductivities of the superconducting to the normal state. Although the specimen employed in this experiment has the resistivity ratio of 44, the magnetization measurements indicate that the specimen is a second kind superconductor due to a trace of impurity contained. High critical fields and the wide range of the field transition can be interpreted in terms of a second kind superconductor.

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Dielectric, pyroelectric, thermal, optical and crystallographic properties of CsH₃(SeO₃)₂ were studied. Various pyroelectric tests indicate essentially no net spontaneous polarization below the Curie point, −128°C. Correspondingly, no ferroelectric hysteresis loop appears; D vs E curves are linear except for an impressive form having the critical field, E_c, in a narrow temperature range just below the Curie point, T_c, under an applied ac field perpendicular to (100). The critical field increases with decreasing temperature and is given with sufficient approximation by an expression; E_c=2.3×10⁴(T_c−T)^1⁄2 V/cm. The dielectric constant, ε_⊥(100), shows a peak at the Curie point, which shifts, to lower temperature on application of a biasing dc field. These dielectric results may well be interpreted as a field-induced transition phenomenon from an antiferroelectric state to a paraelectric one.
The measurement of specific heat as a function of temperature yields δS=0.81 cal/mole·deg. The upper phase has symmetry P_\bar1 and the cell dimensions are a_u=9.32₆ Å, b_u=6.52₆ Å, c_u=5.83₅ Å, α_u=91.5°, β_u=105.1°, γ_u=91.1°. The lower phase also has symmetry P_\bar1, but superstructure along the c axis, i.e., c_l\fallingdotseq2c_u.

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The emission spectra from NaI(T1) excited by X-Rays at the temperature of liquid hydrogen showed the peaks at approximately 616, 546, 437, 379, 332, 299 and 285 mμ. The 332 mμ band is predominant at only the temperatures of liquid hydrogen and liquid helium, and is thought to arise from the T1 dimers, consisting of a pair of T1⁺ ions substitutionally displacing two alkali ions in the nearest neighbour (⟨110⟩ direction). T1 dimer becomes an effective luminescent emission center at very low temperature.
The emission spectra from CsI(T1) excited by X-rays at the temperature of liquid helium showed a superposition of 595, 537 and 474mμ bands. The luminescence being weaker at lower temperature than at the room temperature, it shows no band in the ultraviolet region. In the following, temperature dependence of emission spectra from NaI(T1) and CsI(T1) excited by X-rays are reported and some discussion concerning with also some experiments carried out by other authors are presented.

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Two types of EPR signals were obtained for CdCl₂:Cu and MgCl₂:Cu. One has an axial anisotropy around the crystal c-axis and the other is isotropic. The former may originate from the substitutional cupric ions whose environments undergo Jahn-Teller distortions and the latter seems to originate from interstitial cupric ions in crystals. The values of g-tensor and hyperfine constant are g_w=2.162±0.001, g_u=g_v=2.144±0.001, |A_w|≈101×10⁻⁴cm⁻¹, |A_u|≈|A_v|≈80×10⁻⁴cm⁻¹ (CdCl₂:Cu); g_w=2.178±0.001, g_u=g_v=2.154±0.001, |A_w|≈92×10⁻⁴cm⁻¹, |A_u|≈|A_v|≈75×10⁻⁴cm⁻¹ (MgCl₂:Cu) for the former and g_x=g_y=g_z=2.168±0.002, |A_x|≈|A_y|≈|A_z|≈118×10⁻⁴cm⁻¹ (CdCl₂ : Cu); g_x=g_y=g_z=2.192±0.002, |A_x|≈|A_y|≈|A_z|≈109×10⁻⁴cm⁻¹ (MgCl₂:Cu) for the latter.
The optical absorption in MgCl₂ (343mμ and 375mμ) can be attributed to the transitions of electron-transfer from the chlorine ions to the cupric ion

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The mechanisms of radiation hardening in sodium chloride crystals were studied by examining the stress-strain curves and the temperature dependence of the flow stress. It was found that the flow stress of pure crystal is far more temperature insensitive than those which were doped with Ca⁺⁺ -ions both before and after irradiation. The experimental results were compared with the Fleischer’s theory of the temperature dependence of the flow stress and a qualitative agreement was obtained for both crystals in the temperature range from 77°K to 300°K. Possible mechanisms of the radiation hardening were discussed on the basis of the present results.

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Magnetic susceptibility of Mn₃B₄ with D7_b type structure was measured in the temperature range from liq. N₂ temperature to c.a. 900°K. Magnetic characteristic of Mn₃B₄ is assured to be antiferromagnetic and shows a sharp peak at 392°K. Experimental results suggest that an antiferromagnetic ordering in this phase consists of a +−+− stacking of ferromagnetic layers. An abrupt decrease in magnetic susceptibilities was observed below 226°K, and is ascribed to a transition to canted or conical screwed ordering in the layers.

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Anisotropy of the absorption saturation of ferromagnetic resonance under a high rf-field was measured in a spherical sample of single crystal Zn₂Y by the parametric excitation method. The measured absorption consists of three parts: a main mode and two subsidiary absorptions. To analyse the high power behaviors of these absorption peaks, an anisotropic dispersion relation of spin waves is derived from a phenomeno-logical treatment. The first and the second order non-linear behaviors are distinguished clearly in agreement with theory. Details of two subsidiary peaks accompanying with the main mode resonance are explained in terms of the dissipation processes due to the excitation of the spin wave corresponding to the obtained spectrum.

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The sharp absorption peaks appearing at about 0.52 μ and 0.29 μ for Cu and Ag, respectively, are explained by the interband transitions from the d band to the conduction band. The energy spectra of the d band and the conduction band are expressed by simple functions consistent with the calculated band structures. It is shown that the wave-length dependence of the calculated conductivity agrees fairly well with experiments.
From the results of the experiments about the change of the electronic specific heats and the shift of the absorption edge in alloying Zn in Cu, the change of the electrical conductivity is derived.

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The small-signal complex permittivity of ferroelectric barium titanate and triglycin sulphate single crystals in the frequency range 100 kc/s to 2 Mc/s was measured, during the polarization reversal process excited by rectangular pulse field. During the switching pulse, both the components of the complex permittivity have anomalously large values. The time dependence of the imaginary part of the complex permittivity has roughly the same shape as the switching current curve, while the real part lags considerably behind and reaches its maximum value at a later time. The frequency dependences of the complex permittivity measured on the rising part of the switching current differ in shape from those measured on the falling part. None of these frequency dependences is a simple Debye relaxation, not even in barium titanate. A possible explanation of the increase in complex permittivity during switching on the basis of the nucleation model of switching is suggested, in which the nucleation probability is modulated by the weak alternating field.

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A theory of the increase in complex permittivity (Δε^*) during switching is developed for BaTiO₃ and TGS on the basis of nucleation models for the polarization reversal process. It is shown that the Pulvari-Kuebler phenomenological description of switching can be used to derive satisfactory expressions for Δε^*; the reason for this is that this description is an approximation of the model theories of switching. Expressions are also calculated for Δε^* from the nucleation model of switching and from the growth model of residual nuclei, taking into consideration only their lateral growth. The calculated time and frequency dependences of Δε^* during switching are compared with the experimental results given in Part I of this paper. In the nucleation theory of switching, the consideration of the influence of an alternating electric field on the nucleation of nuclei on the domain walls leads to a time dependence of Δε^* corresponding to experiment. Accordingly, the consideration of this influence on the growth of residual nuclei has an analogous result. The infiuence of an alternating field on the nucleation of isolated nuclei gives time dependences which do not agree with experiment; the increase in Δε^* during switching cannot be caused by this mechanism alone. The main characteristics of Δε^* can thus be explained without introducing a new equation of motion for domain walls, not contained in the theory of polarization reversal.

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The measurements were made on the electrical resistivity, the magnetoresistance and the Hall coefficient of the bismuth alloys containing small amounts of tin or tellurium as function of temperatures between 4.2° and 400°K. In Bi-Sn alloys a hump appeared in the resistivity, the magnetoresistance and the Hall coefficient versus temperature curves respectively, while in Bi-Te alloys it did in the magnetoresistance and the Hall coefficient versus temperature curves of only heavily-doped specimens. Such behaviors could be explained qualitatively in terms of the electronic band structure and the change of the carrier concentration. Especially, the appearance of such humps in Bi-Te alloys were explained in terms of the thermal excitation of the electrons from the Fermi level to the upper empty conduction band.

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A mechanism of formation of dislocation dipoles was discussed without assuming climb nor cross slip of dislocations in face-centered cubic crystals. The greater part of Frank-Read sources in the face-centered cubic crystals are spiral or cone dislocation sources, which cause homogeneous slip. When dislocations producing the homogeneous slip meet with an intersecting dislocation with Burgers vector crossing the slip plane, the formation of jogs differs considerably from that in dislocations on the same atomic plane. A jog in each dislocation can be removed leaving behind a large jog, which results in a dislocation dipole. The geometries of such interactions were illustrated for some simple cases. The difference in dislocation arrangements between pure metals and alpha-brass or copper-aluminium alloys was attributed to the effect of short range order hardening, which hinders the operation of the spiral or cone dislocation sources.

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Nonlinear magnetoresistance in bismuth is studied at 4.2°K with fast rise time pulses in a steady magnetic field up to 16 kOe. For 50–100 nsec pulses, ohmic relations are obtained up to E₀∼5(sH/c), and the predicted hot electron effect is found to be negligibly small. It turns out that the strong nonlinearity discovered by Esaki takes place after a finite time τ_b corresponding to buildup of a phonon flux due to the ultrasonic amplification. Two different types of magnetic field dependence of τ_b are observed, namely, τ_b∝H⁻² for τ_b>>d⁄s, and τ_b∝H⁻¹ for τ_b<<d⁄s, where d⁄s is the transit time of the phonon flux across the sample. Continuous oscillations are observed whose period is considerably smaller than the round-trip time of the phonon flux.

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The dependences of the photoconductivity upon the CuCl film thickness and temperature have been examined, with excitations into the exciton band and the band to band transition regions. For the interpretation of the thickness dependence, the exciton migration has been found to be essential and its diffusion length is determined as ∼2μ at 130°K. The film surface receives the illumination damage by the ultra violet light at room temperature and make the photoconduction decrease in great deal. The comparison has been made between the temperature variation of the photoconductivity and that of the luminescence due to the exciton which has been reported previously. At higher temperatures above 140°K, the photoconductivity increases rapidly and the photocurrent shows the so called secondary current and the thermal decomposition of free excitons and ionization of trapped charge have been concluded to play a part for this increase.

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Electrical resistivities of secondary defects in quenched aluminum have been determined experimentally. The resistivity of a void is found to be proportional to the square of the void size and is obtained to be 2.5×10⁻¹² s²Ωcm⁴, where s is the length of a side of the regular octahedral void. The stacking fault resistivity is (4.0±1.5)×10⁻¹³Ω cm². The upper limit value of the dislocation resistivity is 1.5×10⁻¹⁹Ω cm³.

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The formation conditions and mechanism of double layer stacking fault dislocation loops have been studied experimentally. It is found that slow quenching such as quenching into oil or re-quenching to lower temperature liquid immediately after quenching are favored for the double layer loop formation. It is confirmed that double layer loops are formed by additional forming another faulted loop on the plane which is one atomic distance apart from the original faulted loop. Possible reasons for the preferential formation of the newly formed faulted loop are considered. This double layer loop formation implies that some thermal equilibrium vacancy clusters in aluminum have a collapsed structure.

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The rectifying effect of a double membrane composed of two layers of positively and negatively charged membranes is discussed on the basis of diffusion equations for ions. Both cases of homogeneous membranes and of porous membranes are studied using the following main assumptions: the average distributions of ions inside and outside the boundary of the membrane are subject to the Boltzmann equilibrium distribution and the gradient of electric potential is constant in the membrane.
It is found that rectification is due to an asymmetric distribution of ions with respect to the interface between two layers. In order to achieve effective rectification the concentration of fixed charge of the membrane must be higher than that of the bulk solution. If an appropriate value is taken as the effective mobility of ions, results agree at least qualitatively with experiments.

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The helical states of copolymers of D, L-amino acids are discussed statistical mechanically by modifying the method of Lifson and Roig for homopolymers of amino acids. Two simple copolymers, Model A of L_nD_m type (a sequence of n L residues followed by m D residues (n, m>>1)) and Model B of L_nD_pL_m type (n, m>>p) are discussed in detail, under the condition that the left (right)-handed helix is more stable for homopolymers of D(L)-residues. In Model A, the number of D-residues is found small which are forced to take the right-handed helix, subjecting to the sequence of L-residues of right-handed helix. In Model B, the slight change in number of D-residues suffices to reverse the helical sense of the D-part.

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The discharge in the crossed field is divided into three types under the condition of which current is 0.1∼30 mA, pressure is 0.01∼10 mmHg and magnetic field is 50∼13500 gauss. In strong magnetic field, there is a new type of stable discharge in which the electron sheath forms the large anode fall and gas atoms are mainly ionized by electron impact in the anode fall region. With an increase in the current, stable discharge transits into an intermittent discharge accompanied with the spontaneous oscillation. The oscillation is induced in the region of plasma in which space charge distributes uniformly. In weak magnetic field, there is another stable discharge that is an usual glow discharge.

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Stationary striations appearing in the plasma column of low pressure argon h. f. discharge brought about in cylindrical discharge tube of diameter from 5.8 to 18 mm are investigated experimentally for the pressure range from 0.07 to 8 mmHg. Their spatial intervals (so-called “wave-length”) are proportional to the electrodes distance within a limited range of the wave-length. The relation between the wave-length and the electrodes distance is shown by sawteeth-like characteristics.
The wave-length increases linearly as the radius of the discharge tube increases. But it decreases exponentially as the gas pressure increases. The influence of the frequency of the h. f. source does not exist over a range from 5 mc to 53 mc. The wave-length, however, increases as the h. f, power increases. When a d. c. voltage is superposed on the h. f. field through another pair of electrodes, striations move from positive side to negative side at a velocity proportional to the d. c. current. These results indicate that the stationary striations appearing in h. f. discharge can be regarded as a special state of moving striations.

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The negative absorption of microwave radiation was confirmed at the electron cyclotron frequency in a weakly ionized xenon plasma. The gain was about 11 db for the input power in the range between about 10⁻¹¹ W and 10⁻⁹ W. Using an expression for the Q of plasma in a plasma- cavity system, we analyzed the experimental results and obtained −10² per meter as the value of the energy absorption coefficient α_ω, under the assumption that the velocity distribution of plasma electrons is a δ- function.

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The effect of temperature dependent heat sources on heat transfer in the laminar flow over a fiat plate in the presence of suction is examined. Solutions of the energy equation have been obtained for P_r=1, valid for values of the suction parameter exceeding 3 and the heat transfer at the wall has been analysed.

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Vortex streets behind circular cylinders and fiat plates were investigated experimentally in a water tank. Photography and hot-wire techniques were used. The important points resulting from the investigation are as follows. (1) Walls increase the stability of the wake. (2) Two parallel walls have a compressing effect on the vortex street. (3) The vortex street of a single row is formed near a single plane wall. (4) Not only laminar wakes but also turbulent wakes show a strong tendency to form the Kármán vortex street. (5) When a certain periodic disturbance is given to a wake, a stable symmetrical vortex street are formed. (6) Vortex filaments behind tapered cylinders and whirling cylinders are straight but inclined to the cylinder axis.

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