Latest research activity on the standard of high‐voltage impulse in Japan

A national‐standard‐class impulse voltage measuring system in Japan was developed in the consignment research of the Ministry of Economy, Trade and Industry (METI) and New Energy and Industrial Technology Development Organization (NEDO) from 1998 to 2006. The standard measuring system for the impulse voltage measurements is to be managed by the Japan High‐voltage Impulse testing Laboratories Liaison (JHILL) established under the Japan Electric Machine Industry Association (JEMA). In this paper, the composition of this standard measuring system, its performances and international compatibility, the domestic traceability system and related latest activities are described. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Mechanism of lower oxidizability of eicosapentaenoate than linoleate in aqueous micelles

The aerobic oxidation kinetics of methyl eicosapentaenoate (20:5n-3) and methyl linoleate (18:2n-6) were compared in homogeneous chlorobenzene solution and in Triton X-100 aqueous micelles at 37°C. The rate of disappearance of 20:5n-3 was two times faster than that of 18:2n-6 in chlorobenzene, while the former was five times slower than the latter in aqueous micelles. It was also observed that ΔO₂=Δ18:2n-6 and ΔO₂=2Δ20:5n-3 in aqueous micelles. In the oxidation of a 1∶1 mixture of 20:5n-3 and 18:2n-6 in micelles, the rate of disappearance of 20:5n-3 was 3.6 times faster than that of 18:2n-6, and the rate of total substrate disappearance was reduced by a factor of 5 as compared with 18:2n-6 oxidation. These data suggest that the peroxyl radical derived from 20:5n-3 is more polar than that from 18:2n-6, and the former is likely to diffuse from the core to the micelle surface. This lowers the oxidizability for 20:5n-3 in aqueous micelles by enhancing the termination reaction rate for peroxyl radicals and by reducing the rate of propagation since there may be more 20:5n-3 peroxyl radicals at the surface than in the micelle core.     

Concentrations and profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans in soils from Korea

Soil samples were collected from Changwon and Masan Cities, Korea, and analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs). Nearly all tetra- through octachlorinated PCDDs/DFs including the 17 2,3,7,8-substituted PCDDs/DFs were detected in all samples. Total concentrations of PCDDs/DFs and of 2,3,7,8-tetrachlorinated dibenzo-p-dioxin (TeCDD) equivalents (TEGs) in soils ranged from 35 to 121,400 pg/g, dry weight, and from 0.2 to 3720 pg of I-TEQ/g, respectively. On the basis of guidelines for TEQ concentrations established in Germany and the United States, 9 of 23 soil samples (39% of the total samples analyzed) could not be expected to pose human health hazards. The rest of 61% of soils need measures such as investigations of source identification, soil decontamination, and/or soil removal. Total concentrations of PCDDs/DFs were greater at or near four industrial sites, which are concerned with the steel industry, petrochemical-related industry, and industrial waste incineration, than other areas. This indicates the presence of potential source areas. Soil collected from a site 50 m from an open-burning industrial waste incinerator in an industrial complex was heavily contaminated, containing a total concentration of PCDDs/DFs of 121,400 pg/g, dry weight. PCDDs/DFs were also detected in soils from the top of a 200 m mountain indicating a wide dispersal of PCDDs/DFs by atmospheric transport from point source areas. The congener pattern and relative proportions of PCDFs in soils suggest that commercial PCB preparations such as Kanechlors may be one of the sources. The wide range of PCDD/DF isomers detected in soils from many locations also suggests a multitude of sources, in addition to commercial PCBs, such as incineration of industrial wastes such as car tires, scrap wires, plastics, papers, and emission of automobile exhaust.     

Glass Formation in the System SiO2–PbO Containing Transition-Metal Oxides

Glass-forming regions, valence states, and viscosities in SiO₂–PbO systems containing various transition-metal oxides as a third component were investigated. The glasses were prepared by melting in an open atmosphere. The glass-forming regions ranged as follows: MnO≡ZnO > FeO_1.5>NiO. The ratios Fe²⁺/(Fe²⁺+ Fe³⁺) and Mn³⁺/ (Mn³⁺+ Mn²⁺) in the glasses were determined by chemical analysis. The Fe²⁺/ (Fe²⁺+ Fe³⁺) ratio in SiO₂–PbO–FeO_1.5 glasses ranged from 0.016 to 0.050. The Mn³⁺/ (Mn³⁺+ Mn²⁺) ratio in SiO₂–PbO–MnO glasses ranged from 0.056 to 0.30. The fraction of manganese (III) ions in the glasses varies considerably with the glass composition. The effects of transitionmetal oxides on the viscosity are discussed.     

Application of Microprocessor to Cruise-Control System

A new cruise-control system incorporating a microprocessor has been developed. This system provides a preset speed function to preset a driving speed with a dial. Functions such as transmission control and fail-safe-against-abnormality have been realized.     

A case of a patient diagnosed with malignant mixed Müllerian tumor of the ovary who conceived after conservative surgery and adjuvant chemotherapy

A case of successful pregnancy after treatment of stage Ia malignant mixed Müllerian tumor of the ovary is described. This tumor is very rare and usually occurs in postmenopausal women. cis-platinum-based chemotherapy following the primary operation in the early stage is the most effective treatment, although most of the tumors have been found in the advanced stage. In this patient, treatment with unilateral salpingo-oophorectomy to preserve fertility was performed and followed by cis-platinum-based chemotherapy for 5 years. Two years after completion of the chemotherapy, she spontaneously conceived and the course of the pregnancy has been uneventful to this point.     

Application of Laser Hologram Interferometry to the Distortion Determination of Sugar-Coated Tablets

Sugar-Coated tablets of different core materials were prepared and the degree of distortion of the sugar coat was determined by the laser holographic interferometry of double exposure method. It was found that, as the degree of expansion of the tablet core material increased, the sugar coat became more distorted. By the present method, nondestructive measurement of a minute amount of distortion is possible and thus superior to conventional methods.     

Electrical Properties of PTCR Barium Titanate

When properly doped, barium titanate ceramics display positive temperature coefficient resistance (PTCR) behavior. This has been proved to be a Schottky barrier type of grain-boundary effect. However there has not yet been a complete point-to-point comparison between the experimental data and theory for the entire set of the material nonlinear dielectric properties. In this study, a methodology has been developed which allows the study of the depletion layer dielectric properties while the PTCR effect is being investigated. An equivalent dielectric constant, the value of which is to be determined from this experiment, is treated as an average of the dielectric properties of the depletion layer and is used to analyze the grain-boundary resistance and capacitance data based on a simple double-depletion-layer model. The theoretical relationship between this equivalent dielectric constant and the material dielectric properties is also explored in this study.     

In situ Observation of the Growth of Ribbon-like Thin Films of Bi-2212 on an Ag Substrate

We have developed a simple technique to grow ribbon-like single crystalline films of Bi- 2212 on Ag substrates. The process is performed under ambient pressure only by heating a Bi-2212 pellet on the edge of the substrates. ¹ The ribbon-like films thus grown showed sharp superconducting transitions with an onset temperature of 80K. The formation of the ribbons was studied by observing their growth with a high- temperature microscope. In situ observation with the microscope revealed that most of the ribbon crystals grew during the 10 minutes of the plateau at 905° C. In particular, the early part of the plateau was the dominant stage of growth.     

High‐mobility self‐aligned top‐gate oxide TFT for high‐resolution AM‐OLED

High‐mobility and highly reliable self‐aligned top‐gate oxide thin‐film transistor (TFTs) were developed using the aluminum reaction method. Al diffusion to the oxide semiconductor and homogenization of the oxygen concentration in the depth direction after annealing were confirmed by laser‐assisted atom probe tomography. The high mobility of the top‐gate TFT with amorphous indium tin zinc oxide channel was demonstrated to be 32 cm²/V s. A 9.9‐in. diagonal qHD active‐matrix organic light‐emitting diode (AM‐OLED) display was fabricated using a five‐mask backplane process to demonstrate an applicable solution for large‐sized and high‐resolution AM‐OLEDs.