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1.
Analysis on steady-state and transient heat transfer on a flat plate at the middle of a parallel duct immersed in He II was performed for bath temperatures from 1.8 to 2.1 K at 101.3 kPa. Two-dimensional computer code named SUPER-2D developed by the authors based on the two-fluid model and the theory of mutual friction was used. Steady-state critical heat flux (CHF) and the time lag from the application of a step heat input to λ transition, that is called a lifetime, were obtained numerically for various step heat fluxes and for the channel gaps from 2 to 20 mm. Effect of the gap restriction on the CHF and the lifetime were clarified. The solutions were compared with the experimental data for the ducts with the same structures and the corresponding conditions. They agreed well with the experimental data. The heat transport mechanism in the parallel duct was clarified. 相似文献
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H Miyachi Y Koiso R Shirai S Niwayama JO Liu Y Hashimoto 《Canadian Metallurgical Quarterly》1998,46(7):1165-1168
The synthesis and tumor necrosis factor (TNF)-alpha production enhancing activity of substituted 3'-methylthalidomides on human leukemia cell line HL-60 stimulated with 12-O-tetradecanoyl-phorbol 13-acetate (TPA) are described. Though the introduction of an electron-donating amino group at the phthaloyl moiety of alpha-methylthalidomides enhanced the activity, substituted alpha-methylthalidomides showed decreased stereoselectivity as compared to that of non-substituted alpha-methylthalidomide. The data indicates that the TNF-alpha production enhancing activity of thalidomide derivatives depends on both the electronic-state of substituents at the fused benzene ring and the stereochemistry of the glutarimide moiety. 相似文献
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Masayuki Shirai Chandrashekhar V. Rode Eiichi Mine Akiyoshi Sasaki Osamu Sato Norihito Hiyoshi 《Catalysis Today》2006,115(1-4):248-253
Catalytic ring hydrogenations of naphthalene and 1-naphthol were studied over several supported metal catalysts in supercritical carbon dioxide solvent at low temperature. Higher concentration of hydrogen in supercritical carbon dioxide and lower reaction temperature were responsible for higher catalyst activity and selectivities to the desired partial ring hydrogenated products as compared with those observed in organic solvent for the same catalyst. 相似文献
6.
An industrial melt‐spinning process of tetrafluoroethylene– hexafluoropropylene copolymer (FEP) using an extruder was studied. The novel “spinneret,” having both a large‐diameter spinning nozzle and a high‐temperature vessel, was used to solve the problem of filament breakage on the spinning line caused by high melting viscosity of FEP. The extruder, with its long feed zone, was newly designed to function with a geared pump. The strength of fibers increased with drawing of as‐spun fiber. FEP fibers up to six denier were continuously produced through long‐run production. According to this new process, FEP fibers can be supplied for textile or industrial application. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2366–2371, 2002 相似文献
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Tatsuki Oda Masafumi Shirai Naoshi Suzuki Kazuko Motizuki 《Journal of Superconductivity》1994,7(3):555-558
The lattice dynamics of an oxide spinel LiTi2O4 is studied by taking account of the electron-phonon (EP) interaction derived on the basis of the realistic tight-binding bands fitted to the first-principles bands. Due to the characteristic dependences of the EP interaction on wavevectors and vibrational modes, a remarkable frequency renormalization of the O vibrational modes, which hybridize with the Ti vibrational modes, is obtained over a wide region of the Brillouin zone. The overall features of the calculated phonon density of states are in agreement with those observed by the inelastic neutron scattering measurements. By using the EP interaction and the renormalized phonon frequencies we have calculated the EP spectral function
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F(). The superconducting transition temperature, gap function, and tunneling spectra are calculated by solving the Éliashberg equation. The results agree well with the observations. 相似文献
8.
Wang Angelina Liu Alexander Zhang Ryan Kleiman Anat Kim Leslie Zhao Dora Shirai Iroha Narayanan Arvind Russakovsky Olga 《International Journal of Computer Vision》2022,130(7):1790-1810
International Journal of Computer Vision - Machine learning models are known to perpetuate and even amplify the biases present in the data. However, these data biases frequently do not become... 相似文献
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Mei-Ling Chong Nor' Aini Abdul Rahman Raha Abdul Rahim Suraini Abdul Aziz Yoshihito Shirai Mohd Ali Hassan 《International Journal of Hydrogen Energy》2009,34(17):7475-7482
Clostridium butyricum EB6 successfully produced hydrogen gas from palm oil mill effluent (POME). In this study, central composite design and response surface methodology were applied to determine the optimum conditions for hydrogen production (Pc) and maximum hydrogen production rate (Rmax) from POME. Experimental results showed that the pH, temperature and chemical oxygen demand (COD) of POME affected both the hydrogen production and production rate, both individually and interactively. The optimum conditions for hydrogen production (Pc) were pH 5.69, 36 °C, and 92 g COD/l; with an estimated Pc value of 306 ml H2/g carbohydrate. The optimum conditions for maximum hydrogen production rate (Rmax) were pH 6.52, 41 °C and 60 g COD/l; with an estimated Rmax value of 914 ml H2/h. An overlay study was performed to obtain an overall model optimization. The optimized conditions for the overall model were pH 6.05, 36 °C and 94 g COD/l. The hydrogen content in the biogas produced ranged from 60% to 75%. 相似文献