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81.
Yoshikazu Iida Masato Hirai Masato Shiga Tetsushi Ono Tatsuki Inuzuka 《Electrical Engineering in Japan》2023,216(1):e23414
We are planning to develop the new Advanced Distribution Automation System (ADAS) equipped with optical communication network and sectionalizer with sensor for more grid reliability and efficiency on maintenance operation. The new system is featured with the function of fault cause or damaged part estimation. The new sectionalizer captures the waveform of electrical line surge originated by fault and the system analyzes the waveform for this function. This paper mainly introduces the system configuration of ADAS and an early stage examination of fault cause estimation technology. 相似文献
82.
Satoshi Wada Hiroaki Yasuno Takuya Hoshina Hirofumi Kakemoto Yoshikazu Kameshima Takaaki Tsurumi 《Journal of Electroceramics》2008,21(1-4):198-201
Barium titanate (BaTiO3) crystallites with various particle sizes from 22 to 500 nm were prepared by the two-step thermal decomposition method of barium titanyl oxalate. Various characterizations revealed that these particles were impurity-free, defect-free, dense BaTiO3 particles. The powder dielectric measurement clarified that the dielectric constant of BaTiO3 particles with a size of around 58 nm exhibited a maximum of over 15,000. To explain this size dependence, the THz region dielectric properties of BaTiO3 fine particles, especially Slater mode frequency, were measured using the far infrared (FIR) reflection method. As the result, the lowest Slater mode frequency was obtained at 58 nm. This tendency was completely consistent with particle size dependence of the dielectric constant. 相似文献
83.
Yoshikazu Kitajyo Yoko Sakai Hirofumi Tani Atsushi Narumi Noriaki Kaneko Toyoji Kakuchi 《Polymer》2007,48(5):1237-1244
The synthesis of a novel unimolecular reverse micelle, the hyperbranched d-glucan carbamate (3), was accomplished through the carbamation reaction of the hyperbranched d-glucan (1) with the N-carbonyl l-leucine ethyl ester (2) in pyridine at 100 °C. Polymer 3 was soluble in a large variety of organic solvents, such as methanol, acetone, chloroform, and ethyl acetate, and insoluble in water, which remarkably differed from the solubility of 1. The degree of carbamate substitution (DS) for 3 was controlled by the feed rate of 2, and the DS values were in the range of 46.0-93.7%. Polymer 3 possessed the encapsulation ability for water-soluble molecules, such as rose bengal, thymol blue, and alizarin yellow in chloroform, and the encapsulation ability depended on the hydrophilicity of 3 and the molecular size of the dye. The rose bengal (RB) encapsulated polymer (RB/3) showed a slow release from the RB/3 system into water at neutral pH, while the release rate was significantly accelerated by the hydrolysis of the hydrophobic polymer shell under basic conditions. 相似文献
84.
Kazuo Tomita Taisuke Nagasawa Yoshikazu Kuwahara Seiji Torii Kento Igarashi Mehryar Habibi Roudkenar Amaneh Mohammadi Roushandeh Akihiro Kurimasa Tomoaki Sato 《International journal of molecular sciences》2021,22(15)
In cancer therapy, radioresistance or chemoresistance cells are major problems. We established clinically relevant radioresistant (CRR) cells that can survive over 30 days after 2 Gy/day X-ray exposures. These cells also show resistance to anticancer agents and hydrogen peroxide (H2O2). We have previously demonstrated that all the CRR cells examined had up-regulated miR-7-5p and after miR-7-5p knockdown, they lost radioresistance. However, the mechanism of losing radioresistance remains to be elucidated. Therefore, we investigated the role of miR-7-5p in radioresistance by knockdown of miR-7-5p using CRR cells. As a result, knockdown of miR-7-5p increased reactive oxygen species (ROS), mitochondrial membrane potential, and intracellular Fe2+ amount. Furthermore, miR-7-5p knockdown results in the down-regulation of the iron storage gene expression such as ferritin, up-regulation of the ferroptosis marker ALOX12 gene expression, and increases of Liperfluo amount. H2O2 treatment after ALOX12 overexpression led to the enhancement of intracellular H2O2 amount and lipid peroxidation. By contrast, miR-7-5p knockdown seemed not to be involved in COX-2 and glycolysis signaling but affected the morphology of CRR cells. These results indicate that miR-7-5p control radioresistance via ROS generation that leads to ferroptosis. 相似文献
85.
Water activity-adjusted enzymatic partial hydrolysis of phospholipids to concentrate polyunsaturated fatty acids 总被引:2,自引:0,他引:2
Masayo Ono Masashi Hosokawa Yoshikazu Inoue Koretaro Takahashi 《Journal of the American Oil Chemists' Society》1997,74(11):1415-1417
Selective partial hydrolyses of egg yolk phospholipid and squid skin phospholipid were carried out. By keeping the water activity
(a
w) of Lipozyme IM at an intermediate level, it was easy to concentrate docosahexaenoic acid (DHA). It was also possible to
concentrate both DHA and arachidonic acid (AA) simultaneously to a certain level under this a
w range. However, it was impossible to concentrate AA alone when DHA was present. Though there is a limitation in concentrating
AA exclusively, the proposed a
w-adjusted hydrolytic reaction is a promising way for preparing phospholipids rich in DHA. 相似文献
86.
Yoshikazu Suzuki Naoki Kondo Tatsuki Ohji Peter E. D. Morgan 《International Journal of Applied Ceramic Technology》2004,1(1):76-85
Uniformly porous composites with 3-D network structure (UPC-3D) have been recently developed via a pyrolytic reactive sintering process, which takes advantage of the evolved CO2 gas from a decomposing carbonate source (e.g., dolomite, CaMg(CO3 )2 ) and does not require any additional pore-forming agent nor long-time burning-out process. Through liquid formation via LiF doping, strong necks are formed between constituent particles before completion of the pyrolysis of carbonate, resulting in the formation of a strong 3-D network structure. The pore size distribution is very narrow (with typical pore size: ∼1 μm), and the porosity was controllable (∼30–60%) by changing the sintering temperature. This article presents the development details of UPC-3D, and reports the recent findings in CaZrO3 /MgAl2 O4 system, which will be one of the more promising systems for practical applications. 相似文献
87.
Shinji Hirai Eiji Sumita Kazuyoshi Shimakage Yoichiro Uemura Toshiyuki Nishimura Mamoru Mitomo 《Journal of the American Ceramic Society》2004,87(1):23-28
Cerium monosulfide (CeS) powder was synthesized by the reduction of Ce2 S3 powder with metallic Ce, which was obtained from ceria (CeO2 ) powder using carbon disulfide (CS2 ) gas. To obtain the maximum amount of CeS from a mixture of Ce2 S3 and Ce, an excess amount of metallic Ce, a stoichiometric composition, was necessary in the synthesis at 1273 K for 10.8 ks. The preliminary sintering experiments also were performed using a synthetic CeS powder containing a small amount of Ce, Ce2 O2 S, and β-Ce2 S3 as impurities. It was found that the oxygen content in the sintered compact decreases gradually as the sintering temperature increases, because of the removal of the impurities due to the evaporation of the volatile CeO. Single-phase CeS was formed by sintering at 2173 K. To evaluate the activation energy for densification of single-phase CeS, a CeS powder was prepared by milling an initial sintered compact and was used as an ingredient for hot-press experiments. Densification data during hot-press sintering were analyzed using a kinetic equation, showing that boundary diffusion is a rate-limiting process. The results suggest that this boundary diffusion model can explain well the densification data, with an apparent activation energy of 479 kJ·mol-1 . 相似文献
88.
Tateoki Iizuka Hideki Kita Hideki Hyuga Takene Hirai Kazuo Osumi 《Journal of the American Ceramic Society》2004,87(3):337-341
A W2 C-nanoparticle-reinforced Si3 N4 -matrix composite was fabricated by sintering porous Si3 N4 that had been infiltrated with a tungsten solution. During the sintering procedure, nanometer-sized W2 C particles grew in situ from the reaction between the tungsten and carbon sources considered to originate mainly from residual binder. The W2 C particles resided in the grain-boundary junctions of the Si3 N4 , had an average diameter of ∼60 nm, and were polyhedral in shape. Because the residual carbon, which normally would obstruct sintering, reacted with the tungsten to form W2 C particles in the composite, the sinterability of the Si3 N4 was improved, and a W2 C–Si3 N4 composite with almost full density was obtained. The flexural strength of the W2 C–Si3 N4 composite was 1212 MPa, ∼34% higher than that of standard sintered Si3 N4 . 相似文献
89.
Yoichiro Masuda Akira Baba Mamoru Ohmori Hiroshi Masumoto Takashi Gotoh Toshio Hirai 《Integrated ferroelectrics》2013,141(1-3):35-45
Abstract The crystalline structure, dielectric relaxation and ferroelectric properties of the solid solution, Nd x Bi4-x Ti3O12 (NBIT) compound were measured. The Curie temperature of the NBIT ceramics was determined to be 490°C from dielectric measurements. The dielectric constant of the NBIT ceramics shows a small anisotropic property. Polarization switching was observed using a Sawyer-Tower circuit at 50 Hz. Remnant polarizations and coercive fields could not be confirmed since the hysteresis loops were not saturated. The large dielectric relaxation is observed in the frequency range between 100 kHz and 1 MHz. 相似文献
90.
When human polymorphonuclear leukocytes (PMN) were attached to glass coverslips, cells always spread and formed reactive oxygen species prior to any experimental stimulation. To avoid this, a polyvinylidine chloride film was used as an inactive substance to place the cells. Cells engaged in phagocytosis on the film exhibited a specific H2O2-mediated luminol chemiluminescence (LCL) at the cell-particle interface; the cells stimulated with 12-O-tetradecanoylphorbol-13-acetate became aggregated and the LCL was observed at the cell-cell contact. These results corresponded well with those obtained by an electron microscopic H2O2-demonstration method. 相似文献