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951.
Haruhiko Ohta Toshiyuki Mizukoshi Takeyuki Yoshida Yasuhisa Shinmoto 《Microgravity science and technology》2005,17(3):75-81
To realize a concept of solar power satellite with high power generation, it is a promising method to transfer the power by
laser beam using active mirror type amplifiers where cooling of the laser material accepting highly condensed sunray is inevitable.
To remove high heat flux density from a large area, a structure of cold plate consisted of two parallel plates is devised
and the effective liquid supply directly to the bottom of flattened bubbles due to nucleate boiling is realized by the auxiliary
liquid feeder. The critical heat flux is increased by more than 1.5 times from that without the additional liquid supply.
The technology can be applied not only to space but widely to the development of high-performance cold plates employed on
ground. 相似文献
952.
Fumia Toki Associates Yokohama A.Higashide T.lida T.Sakal M.Yoshida K.Todoroki H.Hatakeyama T.Kawata Y.Kishimoto T.Yoshikunt M.Sato Nihon Sekkei Tokyo 刘畅 《建筑细部》2005,(4):56-57
乍看起来,大体量的日本关西国家图书馆并不是非常引人注目,该馆的馆藏能力达到2000万册,目前尚有大量空间可以利用,图书馆最初设在东京,但是由于首都地价过高,因此在那里进行扩建或是重修图书馆的工作是不可能的。 相似文献
953.
Y Yoshida Y Imai T Murakami M Nishikawa M Kurokawa T Yonezawa K Tokunaga Y Fukushima K Wakasa T Kim H Nakamura M Sakon M Monden 《Canadian Metallurgical Quarterly》1999,24(1):66-68
Anomalous continuation of the inferior vena cava with an azygous vein is a rare vacular anomaly. The enlarged venous system may simulate adenopathies or mediastinal and retroperitoneal masses on the radiographs. We describe the case of a patient with lung cancer - a pathological condition which may cause adenopathies at these sites - and a dilated azygous-hemiazygous system resulting from failure of formation of the hepatic segment of the inferior vena cava. 相似文献
954.
Hideki Hyuga Mark I. Jones Kiyoshi Hirao Yukihiko Yamauchi Katsumi Yoshida Hideki Kita 《Journal of the American Ceramic Society》2008,91(1):192-197
The wear behavior of Si3 N4 ceramics sintered with various rare earth additives was studied for nonlubricated sliding under different conditions, and scratch tests carried out in an attempt to correlate the wear behavior. When multiple scratch testing is used the results can be used to indicate the initial wear behavior under fracture-dominated wear of the materials. The additive system used in the sintering of the Si3 N4 ceramics affected the specific wear rate under nonlubricated sliding conditions, and under high load conditions, where fracture is dominant, the specific wear rate was shown to increase in samples sintered with lutetium as a consequence of a strong bonding strength between the grains and grain boundary resulting in a higher degree of brittle fracture. 相似文献
955.
C.F. Canto L.A.S. de A. Prado E. Radovanovic I.V.P. Yoshida 《Polymer Engineering and Science》2008,48(1):141-148
In this study, hybrid materials based on epoxy resin were prepared as transparent self‐supported films by a sol–gel process. 4,4′‐Diaminodiphenylmethane or oligomeric epoxy resin were used as precursors, which were conveniently functionalized with trialkoxysilanes as end‐groups. The effect of the introduction of poly (dimethylsiloxane) was also investigated. The hybrid films showed good thermal stability, a nondefined glass transition temperature, and a dense morphology without phase segregation. The tendency to a flat surface could be observed by atomic force microscopy. The hybrid films also showed good performance as coatings for glass plates, with an improved hydrophobic character in comparison to neat epoxy resin. POLYM. ENG. SCI., 48:141–148, 2008. © 2007 Society of Plastics Engineers 相似文献
956.
Kenichi Hashizume Ryosuke Onji Shinpei Niiki Hideaki Tsukuda Ryota Yoshida 《亚洲传热研究》2009,38(3):156-167
Heat transfer coefficients were measured on tube bundles of fundamental layouts including in‐line layouts embedded horizontally in a liquid‐fluidized bed. Tested tube layouts were single tubes, transverse single tube rows, longitudinal single tube rows, and in‐line arranged tube bundles. A total of 7 kinds of particles were used. Comparisons of the experimental data showed a good agreement with the heat transfer correlation developed for staggered layouts, when the average liquid velocity through each tube bundle was used as the reference velocity for the particle Reynolds number. Distribution of the local heat transfer coefficient was also investigated around tubes. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20245 相似文献
957.
958.
Kou Sugawara Takeshi Nobukawa Masanori Yoshida Yoshihiro Sato Kazu Okumura Keiichi Tomishige Kimio Kunimori 《Applied catalysis. B, Environmental》2007,69(3-4):154-163
Effect of the loading amount of Fe over ion-exchanged Fe-MFI catalysts on the catalytic performance of N2O reduction with NH3 was investigated, and the results indicated that the turnover frequency (TOF) was almost constant in the Fe/Al range between 0.05 and 0.40. The activity of N2O + NH3 reaction was much lower than that of N2O + CH4 reaction over Fe-MFI (Fe/Al = 0.40), and the preadsorption of NH3 decreased drastically the activity of N2O + CH4 reaction. The temperature-programmed desorption (TPD) of NH3 showed the formation of stronger acid sites on Fe-MFI (Fe/Al = 0.24 and 0.40), and the amount of the acid sites agrees well with the desorption amount O2 in O2-TPD in the low temperature range. The acid sites gave a 3610 cm−1 peak (Brønsted acid) in FTIR observation. These results suggest that the acid sites were formed on the bridge oxide ions in binuclear Fe species. Adsorbed NH3 on the strong acid sites inhibited N2O dissociation, which can be related to the low activity of N2O + NH3 reaction over Fe-MFI with high Fe loading. 相似文献
959.
This study investigates the phenomenon of water freezing below the freezing point in polymer electrolyte fuel cell (PEFCs). Water generated on the surface of the catalyst layer was observed simultaneously with visible and infrared images. Surprisingly, it was found that water generated below the freezing point is in the liquid state and that the temperature rises to 0 °C at the time of freezing. It is generally known that heat of solidification is radiated when water in a super-cooled state starts to freeze. This study shows that water generated below the freezing point in polymer electrolyte fuel cells (PEFCs) is in a super-cooled state. 相似文献
960.