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排序方式: 共有594条查询结果,搜索用时 15 毫秒
511.
Namihira T. Tsukamoto S. Douyan Wang Katsuki S. Hackam R. Akiyama H. Uchida Y. Koike M. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(2):434-442
Pulsed power has been used to remove nitric oxide (NO) in a mixture of nitrogen, oxygen, and water vapor simulating the flue gases from a power station stack. The effect of the pulsewidth at a fixed applied voltage on NO removal concentration was studied. The dependence of the energy efficiency of the removal of NO at a fixed applied voltage on the pulsewidth, on the removal ratio of NO and on the discharge current was investigated. This removal energy efficiency increases with decreasing pulsewidth and decreasing removal ratio of NO 相似文献
512.
Leading-edge vortices on a simple delta wing were visualized by using pressure-sensitive paint (PSP). PSP is an optical pressure measurement technique based on oxygen quenching of luminescent molecules. In the present study, we used PSP composed of platinum octaethylporphyrine (PtOEP) and fluoropolymer (poly-IBM-co-TFEM [Poly (isobutylmethacrtlate-co-trifluoroethylate)]). This new paint has higher sensitivity to pressure and lower sensitivity to temperature than previous ones, reducing an error due to temperature variation during a wind tunnel test. A thin coating of PSP was applied to a delta wing model with 70-degree leading-edge sweep. The coating was excited by Xenon light and emission from the coating was detected by a high-resolution CCD camera. Tests were done at subsonic speeds in the 0.2-m Supersonic Wind Tunnel at the National Aerospace Laboratory in Japan. Complicated flow structures on the delta wing including primary and secondary vortices were clearly visualized using pressure-sensitive paint. An a priori calibration technique was used to convert measured luminescent intensity into pressure. The obtained pressure distributions were in good agreement with pressure tap data. Pressure maps were obtained for various Mach numbers, Reynolds numbers and angles of attack. It was found that an increase in Mach number delayed vortex breakdown while Reynolds number had little effect on the vortex formation. 相似文献
513.
Akifumi Kawamura Chie Kojima Michihiro Iijima Atsushi Harada Kenji Kono 《Journal of polymer science. Part A, Polymer chemistry》2008,46(11):3842-3852
The comb‐type polyelectrolyte, poly(ethylene glycol)‐graft‐poly(allyl amine) (PEG‐g‐PAA), was synthesized to prepare polyion complex (PIC) micelles with Aspergillus Niger Glucose oxidase (GOD). Even after mixing GOD and PEG‐g‐PAAs with various PEG contents, the resulting mixtures remained transparent but the mixture of GOD and PAA homopolymer immediately precipitated. In the mixtures prepared with a stoichiometric mixing ratio, the formation of PIC micelles with a core‐shell structure was suggested from dynamic and static light scattering measurements. Glucose, the substrate for GOD, could easily diffuse into the PIC micelles, and the GOD molecules were active even in the core of the PIC micelles. GOD didn't lose its enzymatic activity through entrapment into the PIC micelles. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3842–3852, 2008 相似文献
514.
K Kawano M Hachiya Y Iijima N Sato Y Mizuno 《Journal of magnetism and magnetic materials》2009,321(16):2488-2493
Polycrystalline ferrite materials with the chemical composition of Ni0.49Zn0.49Co0.02Fe1.90Ox have been fabricated using the conventional ceramic sintering method. Grain sizes have been adjusted from ∼2.2 to ∼13.5 μm with changing sintering conditions. From the measurements of the complex permeability, it is suggested that the permeability is dominated only by the spin rotation at mono-domain state and both domain wall and spin rotation contribute at multi-domain state. At mono-domain state, the core loss has been drastically decreased similar to the other work. The measurement result for the loss angle indicates that the low loss state can be maintained up to the higher magnetic field with smaller grain size in spite of the mono-domain state. The simplified wire-wounded type inductors have been also fabricated and characterized. The results have shown that the inductor fabricated with the smaller grain size has a better performance in the quality value under relatively higher current. 相似文献
515.
Novel polygonized single-wall carbon nanotube bundles 总被引:1,自引:0,他引:1
We have synthesized novel crystalline ropes of "polygonized" single-wall carbon nanotubes (SWCNTs). The tubes exhibit rounded-hexagonal cross sections in contrast to the earlier observations of nearly circular tubes. To investigate the structural characteristics of the lattice of SWCNTs we have performed extensive molecular-dynamics simulations. We find several metastable structures of the lattice characterized by different tube cross sections, hexagonal, rounded-hexagonal, and circular, and increasing cell volume. The competition between different tube shapes as a function of tube diameter is analyzed and compared to experiments. 相似文献
516.
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518.
Abe K Abe K Abe R Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Behari S Behera PK Bondar A Bozek A Browder TE Casey BC Chao Y Cheon BG Chistov R Choi Y Dong LY Eidelman S Eiges V Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Gordon A Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hojo T Hokuue T Hoshi Y Hoshina K Hou SR Hou WS Hsu SC Huang HC Igarashi Y 《Physical review letters》2002,88(16):162001
We report a measurement of the D0-D macro(0) mixing parameter y(CP) using 23.4 fb(-1) of data collected near the Upsilon(4S) resonance with the Belle detector at KEKB. y(CP) is measured from the lifetime difference of D0 mesons decaying into the K(-)pi(+) state and the CP-even eigenstate K(-)K(+). We find y(CP) = (-0.5+/-1.0(+0.7)(-0.8))x10(-2), where the first error is statistical and the second is systematic, corresponding to a 95% confidence interval -0.030相似文献
519.
520.
High resolution, transmission electron microscopy results of dynamic observations during the electron irradiation of amorphous phases are presented. The granular image contrast, typical in amorphous structures, fluctuates continuously during high flux irradiation. The fluctuations tend to occur locally in the structure, whereas crystalline regions remain stable. Some local structures are identified during the fluctuations and anisotropic movements are observed at surfaces and interfaces. The phenomenon is attributed to the irradiation-induced instability of a random cluster network, resulting in a decrease of the viscosity and local deformation. 相似文献