Showing papers by "Utsunomiya University published in 1975"

Destabilization of Hydromagnetic Drift-Alfvén Waves in a Finite-β, Collisional Plasma

Abstract: We have observed experimentally the destabilization of both the Alfv\'en and the drift branches of the hydromagnetic, coupled drift-Alfv\'en wave in a steady-state, high-density (${n}_{0}\ensuremath{\approx}{10}^{13}\ensuremath{-}{10}^{15}$ ${\mathrm{cm}}^{\ensuremath{-}3}$) collisional plasma when an axial electron current is drawn along the magnetic field. The measured dispersion relation is in good agreement with solutions of our theoretical dispersion relation.

Optical lineshape for the A1−E transition − comparison of IOA with numerical method

Abstract: Optical lineshape functions for A1−E transitions coupled with phonon modes of a1 and e symmetries are calculated using the independent ordering approximation (IOA) and the numerical method of Longuet-Higgins et al. (EXM). The two kinds of results are compared and it is found that the IOA well reproduces qualitatively the peculiar feature of the lineshape of EXM, as long as considering only the global profile of the lineshape and disregarding its possible structure within the range of the phonon frequency. The condition of the validity of IOA is discussed. Die optischen Linienformfunktionen fur einen mit Phonon-Moden von a1 -und e-Symmetrien gekoppelten A1−E-Ubergang werden mit der unabhangigen Ordnungs-Naherung (IOA) und der numerischen Methode von Longuet-Higgins et al. (EXM) berechnet. Durch Vergleich dieser Ergebnisse wird gefunden, das die IOA die Hauptzuge der Linienform von EXM qualitativ gut reproduziert, sofern man sich auf das Gesamtprofil der Linienform unter Nichtbeachtung der Struktur in der Linienform im Bereich der Phonon-Frcquenzen beschrankt. Die Bedingung fur die Gultigkeit der IOA wird diskutiert.

Quantitative estimation of paper formation and its effect on oil-impregnated paper

Abstract: It is generally considered that paper formation, if it is good, will have little effect on the dielectric breakdown strength of oil-impregnated Kraft paper for oF cable. However, little is known about defining good formation quantitatively.

Pitting Corrosion of Aluminum in Sodium Chloride Solution and Analyses of Surface Films

Abstract: The anodic polarization behavior and time dependence of anodic current of 99.99% aluminum in 0.5N NaCl solution (pH 4, 6, 8.5, 10 and 12) were examined potentiostatially. The surface structure and the composition of corrosion product films formed on the surface were also observed by a scanning electron microscope, X-ray microanalyzer and energy dispersion type X-ray spectrograph, and the pitting mechanism of pure aluminum was discussed. Pitting corrosion of pure aluminum in 0.5N NaCl at pH 8.5 seemed to be caused by Clwhich enters through cracks at the interface between the surface film and a rhombic corrosion product formed at less noble potentials than the pitting potential. This rhombic substance was observed only at pH 8.5, and was not formed at pH 4, 6, and 10 in 0.5N NaCl solutions. In 0.5N NaCl solution at pH 12, the pitting corrosion was affected by chemical dissolution, thus the pitting potential became rather noble. The limiting current observed in the anodic polarization curves in the solutions of pH 8.5, 10 and 12 seems to be controled by the diffusion of OH-. The potential at which pits are induced for pure aluminum in 0.5N NaCl was about -0.743V at pH 4, -0.757V at pH 6, -0.760V at pH 8.5, and -0.710V at pH 10. The main components of the rhombic corrosion product were ascertained as

Stokes Solutions for Flow Near Corners in Three-Dimensions

Abstract: Nature of three dimensional viscous flow near corner formed by the intersection of two quarter-infinite flat plates at various angles has been examined by constructing Stokes slow flow solutions. Specifically viscous flows for intersection angles of π, (3/2)π and 2π have been investigated, which correspond to flows past a semi-infinite flat plate, an external flow past a right angle corner and a quarter-infinite flat plate respectively. On the basis of the Stokes solutions obtained, various types of singularities arising in the flow field are identified over the complete range of intersection angle 0–2π.