The spontaneous formation of a J-like aggregate in Langmuir-Blodgett films of a squarylium dye

The physical properties of chalcogenide-containing squarylium (SQ) dyes with long alkyl chains were examined. The SQ dyes were deposited as Y-type films. The SQ dye of a 6-methylselenazole derivative spontaneously forms a J-like aggregate in Langmuir-Blodgett films at ambient conditions.     

The effects of a convex rear-view mirror on ocular accommodative responses

Convex mirrors are universally used as rear-view mirrors in automobiles. However, the ocular accommodative responses during the use of these mirrors have not yet been examined. This study investigated the effects of a convex mirror on the ocular accommodative systems. Seven young adults with normal visual functions were ordered to binocularly watch an object in a convex or plane mirror. The accommodative responses were measured with an infrared optometer. The average of the accommodation of all subjects while viewing the object in the convex mirror were significantly nearer than in the plane mirror, although all subjects perceived the position of the object in the convex mirror as being farther away. Moreover, the fluctuations of accommodation were significantly larger for the convex mirror. The convex mirror caused the 'false recognition of distance', which induced the large accommodative fluctuations and blurred vision. Manufactures should consider the ocular accommodative responses as a new indicator for increasing automotive safety.     

Development of new‐type outdoor termination using composite insulator with SF6 gas: Commercial use for 77‐kV transmission lines and development for 154‐kV XLPE cable

Recently, composite insulators have been increasingly employed mainly for economic reasons. We have developed a new type of outdoor termination using a composite insulator, which can be installed horizontally on a steel tower in order to reduce the construction cost. In this outdoor termination, SF₆ gas is filled in the composite insulator and a cold shrinkable premolded rubber unit is applied instead of the combined use of a rubber‐molded stress relief cone, epoxy resin insulator and spring unit. The application of the composite insulator, SF₆ gas and cold shrinkable premolded rubber unit reduces the total weight and makes it possible to install the termination horizontally on the tower. The new‐type outdoor termination for 77‐kV XLPE cable has already been applied in commercial use and enabled a reduction of the construction costs for power transmission lines. A 154‐kV new‐type outdoor termination has been developed and its initial electrical tests were successfully completed. This paper describes the design and performance of both 77‐kV and 154‐kV new‐type outdoor termination, and a follow‐up survey of the 77‐kV new termination in a commercial use. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(4): 18– 26, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20511     

TEM,XPS and SIMS Analyzes on Grain Boundary of Lanthanum Chromites

The morphological characteristics, chromium valence state, and cation transport in the vicinity of grain boundary in La_1-xCa_xCrO₃ were investigated by using TEM/EDS, XPS and SIMS techniques. The width of grain boundary was around 1 nm where anomalous enrichment of calcium was observed. Higher valence state of chromium such as Cr⁶⁺(d⁰) was detected in the grain boundaries whereas Cr³⁺(d³) and Cr⁴⁺(d²) were dominant in the bulk. Very fast interdiffusion of alkaline earths was observed in the Sr²⁺-La_0.75Ca_0.25CrO₃ system. All observed phenomena were correlated by assuming the A-site vacancy which may be induced by the formation of Cr⁶⁺ at grain boundaries.     

A large discrepancy between CPM and ESR defect densities in light-soaked a-Si:H

A large discrepancy between defect densities evaluated by constant photocurrent method (CPM) and electron spin resonance (ESR) is investigated for hydrogenated amorphous silicon (a-Si:H) with various thicknesses in the process of light soaking (LS). It is shown by a computer simulation that the inhomogeneous defect distribution across the film thickness caused by a rather small penetration depth of the white light in the thick film is one of the possible origins of the discrepancy. But various other causes should also bring about the discrepancy, and the problem is still a puzzling one.     

Thermo-acoustical waves in thermo-plastic materials

Summary The propagation velocities and the variation of the amplitudes of thermo-acoustical waves in thermo-plastic materials are theoretically investigated. The constitutive equations of anisotropic thermo-plastic materials are derived from the concept of imaginary decomposition of the deformation rate tensor into the elastic and plastic contributions and from that of the plastic potential. From generalized Vernotte's heat conduction law the propagation condition of the jumps of the velocity gradients and of the temperature rate is obtained. In isotropic materials and in the case of a normal stress vector on the wave front we have two purely mechanical transverse waves and two thermo-longitudinal coupled waves. Formulae for the velocities and amplitudes are quite similar with those for thermo-elastic materials. The variation of the amplitude is discussed. There are, in general, three effects on the variation, that is, the non-planar, heat conduction and plastic flow effects. The transverse waves are subjected only to the non-planar effect, while the thermo-longitudinal waves may grow or decay according to the above three effects.     

Cardiac Arrival Time Analyzer

The sequence of excitation of cardiac muscles is greatly affected by any abnormality in the conduction system of the heart. Epicardial mapping for the measurement of activation time at different points is helpful for the diagnosis of such abnormalities. For the measurement of activation time at different points of the epicardial surface, a number of sophisticated instruments, including microcomputer-based ones, have been reported. However, the need for a reliable, low-cost, and easy to operate instrument cannot be denied. In this note, such a cardiac arrival time analyzer is described.     

Nonlinear Earthquake Response Characteristics of a Central Clay Core Rockfill Dam

The effect of the 2008 Iwate-Miyagi Nairiku earthquake (M_J 7.2), Japan on the Aratozawa dam, which is a 74.4 m high rockfill dam with a central clay core located in the area, was studied with a main focus on the change in the vibration period, shear wave velocity, shear modulus, and pore-water pressure. In a vertical section of the central part of the dam, three sets of 3-component accelerometers and 15 pore water pressure meters were installed. During the main shock, the acceleration exceeded 10 m/s² at the gallery, inducing large shear strains in excess of 10^-3 and a sudden build-up of the excess pore water pressure in the core. Due to the large strains, the shear wave velocity and shear modulus showed a significant decrease from their initial values and the vibration period was elongated. The decreased shear wave velocity gradually recovered toward the end of the main shock, and continued to recover with the passage of time. The full recovery of the wave velocity was found to take at least one year, while the dissipation of the excess pore water pressure proceeded more quickly than the recovery of the wave velocity.     

Characteristics of a generalized fin-line for millimeter wave integrated circuits

Generalized fin-lines are analyzed which consist of slots located on more than one interface between dielectric layers inserted in parallel with the E-plane of a waveguide. The analysis is based on a simplified formulation technique based on the spectral domain immittance matrix followed by a Galerkin's method. It allows as many slots as one desires at each interface, and the locations and the widths of these slots are arbitrary. The numerical process to carry out the present analysis is rather efficient. Some numerical data, including propagation constants of the propagating modes as well as characteristic impedances are presented for several structures considered useful for millimeter-wave circuit applications.