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81.
82.
M. Tamura M. Takahashi J. Ishii K. Suzuki M. Sato K. Shimomura 《Journal of Thermal Spray Technology》1999,8(1):68-72
Multilayered thermal barrier coatings (TBC) with different functions were proposed for the hot section components of land-based
gas turbines. This article describes a multilayered TBC with an oxidation resistant layer. A conventional duplex TBC and a
triplex TBC, in which an aluminized layer was added to the conventional duplex TBC to increase oxidation resistance, were
prepared. It was confirmed by a burner rig test that the triplex TBC with the aluminized layer is resistant to oxidation and
shows high durability in a thermal cycle test, compared with the conventional duplex TBC. The spalling in the thermal cycle
test of each TBC specimen occurred at the same position, when the thickness of the oxidation layer was 11 to 13 μm. The mechanism
of spalling of the coating in the thermal cycle test was discussed in terms of stress in the coating. Stress in the direction
of spalling occurred by an uneven interface between the bond and top coat and increased with growth of the oxidation layer.
It is thought that the high durability of the triplex TBC in the thermal cycle test is derived from suppressing the growth
of the oxidation layer and decreasing the stress due to the addition of the aluminized layer. 相似文献
83.
Wind field simulation and wind‐induced responses of large wind turbine tower‐blade coupled structure 下载免费PDF全文
S T Ke Y J Ge T G Wang J F Cao Y Tamura 《The Structural Design of Tall and Special Buildings》2015,24(8):571-590
Herein, by a case study on a 5‐MW wind turbine system developed by Nanjing University of Aeronautics and Astronautics, the wind field simulation and wind‐induced vibration characteristics of wind turbine tower‐blade coupled systems is analyzed. First, the blade‐nacelle‐tower‐basis integrated finite element model with centrifugal forces induced by rotational blades is established. Then, based on a harmony superposition method and the modified blade element‐momentum theory, the fluctuating wind field of tower‐blade coupled systems is simulated, which considers wind shear effect, tower shadow effect, rotational effect, blade‐tower dynamic and model interaction effects. Finally, the wind‐induced dynamic responses and wind vibration coefficients of the wind turbine tower‐blade coupled structure are discussed through the ‘consistent coupled method’ previously proposed by us. The results indicate that the wind‐induced responses of a large wind turbine tower‐blade coupled structure present complicated modal responses and multimode coupling effect. Additionally, the rotational effect would amplify aerodynamic loads on blades with high frequency, wind‐induced dynamic responses and wind vibration coefficients of wind turbine tower. The centrifugal force effect could also amplify natural vibration frequency of the tower‐blade coupled system and reduce the wind‐induced dynamic responses and wind vibration coefficients of wind turbine tower. The research could contribute to wind‐resistant design of structure for a large‐scale wind turbine tower‐blade system. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
84.
Y Saitoh K Gu S Kin M Yamauchi T Sasaki S Nosaka M Hashimoto K Nakayama K Tamura 《Canadian Metallurgical Quarterly》1996,28(1):286-288
85.
Destruction of volatile organic compounds used in a semiconductorindustry by a capillary tube discharge reactor 总被引:1,自引:0,他引:1
Kohno H. Berezin A.A. Jen-Shih Chang Tamura M. Yamamoto T. Shibuya A. Honda S. 《Industry Applications, IEEE Transactions on》1998,34(5):953-966
Nonthermal plasma technologies offer an innovative approach to the problem of decomposing various volatile organic compounds (VOCs). The authors focused on DC capillary tube discharge plasma reactors to study the decomposition/destruction efficiency for toluene, EGM, trichloroethane and trichloroethylene at 50-2300 ppm levels in dry air. The effects of gas flow rate, VOC concentration and reactor operating conditions on decomposition and analysis of reactant conversion for each VOC were investigated. The results show that VOC destruction efficiency as high as 90% can be achieved, even under a short residence time (3.8 ms) with a destruction energy efficiency of up to 95 g (VOC)/kWh. Laboratory-scale plasma technology was successfully demonstrated for its potential application for VOC control in the semiconductor clean-room environment 相似文献
86.
Miyamoto M. Hirotsune A. Miyauchi Y. Ando K. Terao M. Tokusyuku N. Tamura R. 《IEEE journal of selected topics in quantum electronics》1998,4(5):826-831
The objective of this study was to determine the mechanism of a phenomenon peculiar to phase-change recording regarding the mark shape or mark-forming process. The following results were obtained from our simulation of mark shapes, transparency electron microscope observations, and analysis of reproduced signals. A method of calculating a mark shape by calculating the holding-time profile was devised and its appropriateness was confirmed. We found there were close relationships between the cooling pulse shape, the effective erase ratio, the reproduced signal amplitude, and the noise level, and that the temperature change when the mark edge was cooled has a great influence on the stability of the mark shape and crystallized regions 相似文献
87.
Eighteen sterols were isolated from the aerial parts ofKalanchoe pinnata (Crassulaceae) including four novel sterols,viz. (24R)-stigmasta-5,25-dien-3β-ol (24-epiclerosterol), (24R)-5α-stigmasta-7,25-dien-3β-ol, 5α-stigmast-24-en-3β-ol, and 25-methyl-5α-ergost-24(28)-en-3β-ol. 24-Epiclerosterol and its
Δ7-analog occur together with their 24S/β-epimers in the same plant making this the first report of the isolation of both C-24 epimers of Δ25-unsaturated 24-alkylsterols from a non-marine organism. Iodine-catalyzed isomerization of stigmasta-5,24-dien-3β-ol (24-ethyldesmosterol),
the main sterol ofK. pinnata, yielded 24-epiclerosterol among other products. 相似文献
88.
Dr. Yoshiaki Yasutake Dr. Taiki Nishioka Dr. Noriko Imoto Prof. Tomohiro Tamura 《Chembiochem : a European journal of chemical biology》2013,14(17):2284-2291
Vitamin D3 hydroxylase (Vdh) from Pseudonocardia autotrophica is a cytochrome P450 monooxygenase that catalyzes the two‐step hydroxylation of vitamin D3 (VD3) to produce 25‐hydroxyvitamin D3 (25(OH)VD3) and 1α,25‐dihydroxyvitamin D3 (1α,25(OH)2VD3). These hydroxylated forms of VD3 are useful as pharmaceuticals for the treatment of conditions associated with VD3 deficiency and VD3 metabolic disorder. Herein, we describe the creation of a highly active T107A mutant of Vdh by engineering the putative ferredoxin‐binding site. Crystallographic and kinetic analyses indicate that the T107A mutation results in conformational change from an open to a closed state, thereby increasing the binding affinity with ferredoxin. We also report the efficient biocatalytic synthesis of 25(OH)VD3, a promising intermediate for the synthesis of various hydroxylated VD3 derivatives, by using nisin‐treated Rhodococcus erythropolis cells containing VdhT107A. The gene‐expression cassette encoding Bacillus megaterium glucose dehydrogenase‐IV was inserted into the R. erythropolis chromosome and expressed to avoid exhaustion of NADH in a cytoplasm during bioconversion. As a result, approximately 573 μg mL?1 25(OH)VD3 was successfully produced by a 2 h bioconversion. 相似文献
89.
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