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91.
Kholid Akhmad Hiroaki Okamoto Akio Kitamura Hiromu Matsuda Fumio Yamamoto Yoshihiro Hamakawa 《Solar Energy Materials & Solar Cells》1997,47(1-4)
The experiments investigated phenomena related to direct contact between the DC output of a PV array and the AC power from the utility grid. The results show that the DC power flows through the distribution transformers (DC-injection) saturating their magnetic circuits. The saturation of magnetic circuits makes peak currents, incorporating a large portion of even harmonics, flow through the high-voltage side of the distribution transformer, adding the level of harmonic distortion of its exciting current. With the increase of injecting DC-current to the utility grid, peak currents at the primary side of distribution transformer increases the most, and even among the same effective (rms) values, the increase of primary side current is larger than that of the secondary side current. 相似文献
92.
Masashi Totokawa Syuichi Yamashita Kenji Morikawa Yoshihito Mitsuoka Toshihiko Tani Hiroaki Makino 《International Journal of Applied Ceramic Technology》2009,6(2):195-204
The piezoresistive mechanisms of composite thick films based on RuO2 particles and both calcium-borosilicate and bismuth-borosilicate glass matrices were investigated by chemical and electrical microanalyses. The resistor based on bismuth-borosilicate glass showed higher sensitivity than that based on calcium-borosilicate glass. It was confirmed that the diffusion of ruthenium into glass affects the binding state of RuO2 at the interface of the glass. Furthermore, an intermediate resistive layer is detected around the RuO2 particle. These results suggest that the piezoresistive effect is related to a change in the electrical conductivity of the interfacial reaction layer caused by the diffusion of ruthenium into glass. 相似文献
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96.
Takuji Maekawa Ken Kurosaki Hiroaki Muta Masayoshi Uno Shinsuke Yamanaka 《Journal of Alloys and Compounds》2005,390(1-2):314-317
Polycrystalline samples of perovskite-type strontium molybdate, SrMoO3, have been prepared and the thermal and electrical properties have been measured from room temperature to about 1000 K. The electrical resistivity is of an order of magnitude of 10−5 to 10−6 (Ω m) in the whole temperature range. The Seebeck coefficient is around 4–9 μV K−1. At room temperature, the thermal conductivity is about 30 W m−1 K−1, and it decreases with increasing temperature. 相似文献
97.
Kyung-Cho Kim Hiroaki Fukubara Hisashi Yamawaki Tetsuya Saito 《Journal of Mechanical Science and Technology》2001,15(1):52-60
In this paper, as a new measurement method to estimate the change of material condition, the simplified ultrasonic CT system,
which uses the information of three directions, that is, 90°, + 45° and −45° about inspection plane is proposed. Use of simplified
CT system has two merits: Firstly, the measurement time is very short compared with general CT. Secondly, it can detect sensitively
small defect in vertical or slant direction about inspection plane because the obtained image is CT image calculated from
three directions. From these merits, this method can be considered as an effective method to evaluate material conditions.
The basic performance of the proposed method was confirmed through several specimens with several simple defects. In order
to confirm the applicability of actual NDT, several kinds of welded specimens are investigated. The result showed that the
CT image obtained had good agreement with actual defect of specimens. 相似文献
98.
Takashi Hayashita Hiroaki Noguchi Hisashi Oka Manabu Igawa Makoto Takagi 《应用聚合物科学杂志》1990,39(3):561-569
The sorption behavior of heavy metal thiocyanate complexes was investigated for dibenzo-18-crown-6 (DB18C6) resin and bis[2-(o-methoxyphenoxy)ethyl]ether (BMPE) resin. The DB18C6 resin showed a high sorption ability and the degree of zinc sorption increased significantly with thiocyanate concentration. This behavior was not observed for BMPE resin. The sorption behavior was influenced by the countercation species, and the degree of sorption of zinc ions showed the maximum when the potassium thiocyanate was used as a complexing salt. The sorbed species appear to be KZn(SCN)3, K2Zn(SCN)4 in the potassium thiocyanate system, and Zn(SCN)2 in the lithium thiocyanate system, respectively, according to analysis of the sorption equilibrium. Sodium and ammonium thiocyanate systems show an intermediate behavior of the two. The sorption selectivity for DB18C6 resin depended not only on the hydrophobic nature of heavy metal thiocyanate complexes but also on the stabilization of counter cation species with crown ether matrix, and the sorption selectively was found to be effectively controlled by countercation species according to the cation-chelation mechanism. 相似文献
99.
Hiromasa Tawarayama Etsuko Ishikawa Kenji Yamanaka Katsuhisa Itoh Keiko Okada Hiroshi Aoki Hiroaki Yanagita Yoshihiko Matsuoka Hisayoshi Toratani 《Journal of the American Ceramic Society》2000,83(4):792-796
Praseodymium-doped glasses were prepared in the Ga-Na-S (GNS) system and their optical properties were studied. A single-mode fiber with an attenuation loss of 1.2 dB/m at a wavelength of 1.31 μm was fabricated using an extrusion method, and the amplification characteristics were measured in the bidirectional pumping configuration. We demonstrated a gain coefficient of 0.81 dB/mW at a wavelength of 1.34 μm, which is the highest we have ever reported, and achieved a net gain of 32 dB for a pump power of 90 mW. Highly efficient optical amplification at a wavelength of 1.3 μm was demonstrated in the praseodymium-doped GNS fiber. 相似文献
100.
Jan Kuneš Ryotaro Arita Philipp Wissgott Hiroaki Ikeda 《Computer Physics Communications》2010,181(11):1888-1895
We present an implementation of an interface between the full-potential linearized augmented plane wave package Wien2k and the wannier90 code for the construction of maximally localized Wannier functions. The FORTRAN code and a documentation is made available and results are discussed for SrVO3, Sr2IrO4 (including spin-orbit coupling), LaFeAsO, and FeSb2. 相似文献