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991.
A combined cycle power plant which combines a gas turbine and a steam turbine can achieve high energy efficiency. Many combined cycle plants have been installed worldwide. However, a large‐scale blackout due to combined cycle chain trip‐out occurred in Malaysia in 1996. The cause of this chain trip was considered to be a large drop of system frequency. Thus, there is a need to investigate the stability of the combined cycle power plant for the frequency drop. Several dynamic models of a combined cycle plant have been proposed. In our analysis, we use some of them and build a model for a single‐shaft combined cycle plant. We execute numerical simulations to see how the combined cycle plant behaves when the system frequency drops. The cause and the countermeasure of the combined cycle plant trip‐out are explained. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 143(3): 9–19, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10117 相似文献
992.
993.
Wang Yuehua Yu Meiqi Luo Hongliang Qiao Qi Xiao Zeze Zhao Yan Zhao Lili Sun Hui Xu Zhefeng Matsugi Kazuhiro Yu Jinku 《Journal of Materials Engineering and Performance》2016,25(10):4402-4407
Journal of Materials Engineering and Performance - NiWP alloy coatings electrodeposited on pure copper substrates with additive saccharin (C7H5NO3S) contents of 0-6 g/L were investigated... 相似文献
994.
Yasuo Morimoto Hiroto Izumi Yukiko Yoshiura Kei Fujishima Kazuhiro Yatera Kazuhiro Yamamoto 《International journal of molecular sciences》2016,17(2)
Inhalation studies are the gold standard for the estimation of the harmful effects of respirable chemical substances, while there is limited evidence of the harmful effects of chemical substances by intratracheal instillation. We reviewed the effectiveness of intratracheal instillation studies for estimating the hazards of nanoparticles, mainly using papers in which both inhalation and intratracheal instillation studies were performed using the same nanoparticles. Compared to inhalation studies, there is a tendency in intratracheal instillation studies that pulmonary inflammation lasted longer in the lungs. A difference in pulmonary inflammation between high and low toxicity nanoparticles was observed in the intratracheal instillation studies, as in the inhalation studies. Among the endpoints of pulmonary toxicity, the kinetics of neutrophil counts, percentage of neutrophils, and chemokines for neutrophils and macrophages, heme oxygenase-1 (HO-1) in bronchoalveolar lavage fluid (BALF), reflected pulmonary inflammation, suggesting that these markers may be considered the predictive markers of pulmonary toxicity in both types of study. When comparing pulmonary inflammation between intratracheal instillation and inhalation studies under the same initial lung burden, there is a tendency that the inflammatory response following the intratracheal instillation of nanoparticles is greater than or equal to that following the inhalation of nanoparticles. If the difference in clearance in both studies is not large, the estimations of pulmonary toxicity are close. We suggest that intratracheal instillation studies can be useful for ranking the hazard of nanoparticles through pulmonary inflammation. 相似文献
995.
996.
Noriko Ishida Daisuke Irikura Kazuhiro Matsuda Seiji Sato Teruo Sone Michiko Tanaka Kozo Asano 《Journal of Bioscience and Bioengineering》2010,109(4):341-345
A gene, mf3, encoding glycosyltransferase in glycoglycerophospholipid (GGPL; GGPL-I and GGPL-III) biosynthesis in Mycoplasma fermentans PG18 was identified by genomic analysis, cloned, modified codon usage, and expressed in Escherichia coli. The mf3 gene consists of an open reading frame of 1221 bp encoding 406 amino acids. The mf3 gene product, Mf3, has 27% amino acid homology with glycosyltransferase of Borrelia burgdorferi but no homology to genes of other Mycoplasma species in the GenBank database. The reaction product of Mf3 using 1,2-dipalmitoilglycerol and UDP-glucose as substrates showed a specific sodium adducted ion at m/z 753, which corresponded to glucopyranosyl dipalmitoilglycerol as determined by MALDI-TOF mass spectrometry. Furthermore, in the reaction product by Mf3 and Mf1 which was a cholinephosphotransferase and previously cloned from M. fermentans PG18, an ion at m/z 896 corresponding to GGPL-I was detected by mass spectrometry. The product ions of choline, phosphocholine, and hexose-bound phosphocholine were detected by tandem MS analysis of protonated molecules at m/z 896. From these results, mf3 was identified as a glycosyltransferase. It was suggested that glucose transfer and phosphocholine transfer to 1,2-dipalmitoylglycerol are involved in the GGPL biosynthesis pathway of M. fermentans PG18. 相似文献
997.
Sirichai Tammaruckwattana Kazuhiro Ohyama Shinji Arinaga 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(Z1):S96-S107
This paper proposes a wind turbine emulator (WTE) based on the blade momentum theory, and tests the variable‐speed wind power generation system using a pulse‐width modulation (PWM) converter to verify the accuracy of the emulator. The behavior of the wind turbine for natural wind is reproduced by the WTE based on the proposed theory. The variable‐speed wind power generation system employs a vector control system to control the torque and speed of the permanent magnet synchronous generator in the converter side. The windmill rotational speed is controlled to maximize the efficiency of the wind turbine against wind velocity. And the active power and reactive power are controlled in the inverter side, and the generated power is sent to the grid while controlling the DC link voltage to be constant at the same time. The behaviors of the WTE are compared with the simulation results and experimental results using a real wind turbine. These experimental and simulation results show that the test bench with the proposed WTE has sufficient performance and accuracy to verify variable‐speed wind generator systems. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
998.
We propose a controller tuning method that considers closed‐loop stability after controller tuning without a mathematical plant model. We propose fictitious correlation‐based tuning that yields reasonable controller parameters using a small amount of input and output data. However, closed‐loop stability after controller tuning is not guaranteed in this approach. In this investigation, we impose a stability constraint on the parameter update in order to maintain closed‐loop stability at each parameter update. Further, by introducing particle swarm optimization instead of the Gauss–Newton method to solve the constrained nonlinear optimization problem, the initial value dependence is considerably reduced. The effectiveness of the proposed method is confirmed by a numerical example and experimental results. 相似文献
999.
Kazuhiro Kiyohara Daisuke Uta Yuuya Nagaoka Yurika Kino Hideki Nonaka Midori Ninomiya-Baba Takuya Fujita 《International journal of molecular sciences》2022,23(4)
Several of the drugs currently available for the treatment of premature ejaculation (PE) (e.g., local anesthetics or antidepressants) are associated with numerous safety concerns and exhibit weak efficacy. To date, no therapeutics for PE have been approved in the United States, highlighting the need to develop novel agents with sufficient efficacy and fewer side effects. In this study, we focused on the histamine H3 receptor (H3R) as a potential target for the treatment of PE and evaluated the effects of imetit (an H3R/H4R agonist), ciproxifan (an H3R antagonist), and JNJ-7777120 (an H4R antagonist) in vivo. Our in vivo electrophysiological experiments revealed that imetit reduced mechanical stimuli-evoked neuronal firing in anesthetized rats. This effect was inhibited by ciproxifan but not by JNJ-7777120. Subsequently, we evaluated the effect of imetit using a copulatory behavior test to assess ejaculation latency (EL) in rats. Imetit prolonged EL, although this effect was inhibited by ciproxifan. These findings indicate that H3R stimulation suppresses mechanical stimuli-evoked neuronal firing in the spinal–penile neurotransmission system, thereby resulting in prolonged EL. To our knowledge, this is the first report to describe the relationship between H3R and PE. Thus, H3R agonists may represent a novel treatment option for PE. 相似文献
1000.
通过2个电子参数(结合次数Bot和d轨道能级Mdt)提出了新设计的α型钛(α-Ti)合金。新设计合金Ti-5Al-4Zr-3.6Sn、改性合金Ti-5Al-3Sn-1.9Zr和参考合金Ti-5Al-2.5Sn具有相同的Bot值(3.847)以及不同的Mdt值(2.430,2.426,2.422)。测试了3种α-Ti合金的极限抗拉伸强度(σUTS)、断裂应变(?f)和热盐腐蚀性能。3种α-Ti合金均采用冷坩埚悬浮熔炼技术进行制备。结果表明,3种合金样品均具有均匀的微观结构。在3种α-Ti合金中测量到的α单相晶粒尺寸约为600 μm。Ti-5Al-4Zr-3.6Sn合金的σUTS和?f值为801 MPa和16%,Ti-5Al-3Sn-1.9Zr合金的σUTS和?f值为708 MPa和15%,Ti-5Al-2.5Sn合金的σUTS和?f值为603 MPa和15%。热盐腐蚀测试进行28.8 ks后显示Ti-5Al-4Zr-3.6Sn、Ti-5Al-3Sn-1.9Zr和Ti-5Al-2.5Sn合金的失重率为2.61%、2.83%和3.10%。σUTS、?f和耐热盐腐蚀结果表明,新设计合金Ti-5Al-4Zr-3.6Sn是一种有实际应用潜力的钛合金材料。 相似文献