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81.
The flashover voltage with a backside electrode was found to be lower than that without the backside electrode. Under microsecond pulse voltage application, we describe the characteristics of a creeping discharge developed in the narrow gap with the backside electrode. Using a CCD camera and ultrahigh‐speed camera, we observed the corona extension processes. The lowest flashover voltage was found to be obtained at positive polarity with a SF6 content D = 3%. In the corona extension obtained using an ultrahigh‐speed camera, peculiar differences were observed in the corona extension process. The corona extension increased, and rapid flashover was observed at D = 3%. Using a CCD camera, small coronas were detected from the backside electrode. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(2): 31–38, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20431 相似文献
82.
Goto H. Ohkubo H. Kondou K. Ohkawa M. Mitano H. Horiba S. Soeda M. Hayashi F. Hachiya Y. Shimizu T. Ando M. Matsuda Z. 《Solid-State Circuits, IEEE Journal of》1992,27(11):1490-1496
A 16-Mb CMOS SRAM having an access time of 12 ns under a 3.3-V supply has been developed with a 0.4-μm process technology. An address access time of 12 ns has been achieved by an optimized architecture, the use of an automated transistor size optimizer, and a read-bus midlevel preset scheme (RBMIPS). For better yield and efficient testing, an on-chip test circuit with three test modes has been implemented 相似文献
83.
Tomoyuki Kitano Takayuki Wani Toshiyuki Ohnishi Jiang Li-Fen Yasushi Kuroda Atsutaka Kunai Kazuo Sasaki 《Catalysis Letters》1991,11(1):11-18
Catalytic oxidation of benzene in the gas phase has been studied as a function of the catalyst composition, reaction temperature and the feed conditions of reactant gases, hydrogen, oxygen, benzene as well as diluting inert gas. The catalyst tested is composed of Pd and Cu(I) ions, both of which are supported on silica gel. If one of the two metal species is lacked from the catalyst, no catalytic activity appears. The product is almost exclusively phenol and some accompanying benzoquinone, in particular at lower temperatures, as minor byproduct.On leave from Hua-Dong Institute of Technology, Nanjing, People's Republic of China. 相似文献
84.
Tomoyuki Kawaguchi Yasuhiro Rachi Wataru Sugimoto Yasushi Murakami Yoshio Takasu 《Journal of Applied Electrochemistry》2006,36(10):1117-1125
Highly dispersed ternary PtRuRh/C anode catalysts for direct methanol fuel cells were prepared with various contents and their electro-catalytic activities towards methanol oxidation at 25 °C and 60 °C were examined to investigate the influence of the catalyst composition. Electrocatalysts were prepared by a co-impregnation method using ethanolic solutions of metal precursors and carbon black followed by pyrolysis under reducing conditions. X-ray diffraction analysis revealed that the fcc peaks shifted to higher diffraction angles with increasing Rh content, indicating the alloying of Rh into the fcc structure. In terms of the mass specific current density, the activity towards methanol oxidation differed significantly depending on the catalysts composition and cell temperature. The catalyst prepared at a ratio of Pt:Ru:Rh = 1:1:2 exhibited the highest activity at 60 °C of 155 A (g-Pt)−1 at 0.5 V vs. RHE. 相似文献
85.
A discrete variational-Xα (DV-Xα) method was applied to elucidate the formation of C-O-Si bridging bonds, produced when a silanol group of SiO2 comes close enough to react with a carboxyl group of indomethacin (IM). A decrease in the coordination number (CN) of oxygen atoms per silicon atom at the SiO2 surface increased the net charge (NC) of the silanolic hydrogen atom and decreased the bond overlap population (BOP) between the silanolic oxygen and hydrogen atoms. These changes favored the formation and stabilization of C-O-Si bridging bonds with simultaneous dehydration. The computational results agreed well with our previous experimental study of a ground indomethacin-SiO2 mixture to obtain a better solid dispersion of the drug. 相似文献
86.
A 4‐Fold‐Symmetry Hexagonal Ruthenium for Magnetic Heterostructures Exhibiting Enhanced Perpendicular Magnetic Anisotropy and Tunnel Magnetoresistance 下载免费PDF全文
87.
88.
Hiroyuki Usui Ousuke Miyamoto Teruaki Nomiyama Yuji Horie Tomoyuki Miyazaki 《Solar Energy Materials & Solar Cells》2005,86(1):123-134
The film electrodes of TiO2, which have two functions of opto-electric conversion and storage of electrochemical energy, were prepared by pulsed laser deposition. To investigate the relationship between the photo-rechargeability and the surface structure, the TiO2 film electrodes with different surface morphology were prepared by changing the inert gas pressure during the deposition. The photo-charged quantity was found to be proportional to the third power of the rms of surface roughness. The results suggest that not only the surface but also the interstices between crystal grains near the surface contribute to the photo-charging with low photo-emf. 相似文献
89.
Tajima T Sakata W Wada T Tsutsui A Nishimoto S Miyake M Takaguchi Y 《Advanced materials (Deerfield Beach, Fla.)》2011,23(48):5750-5754
A coaxial nanohybrid consisting of a single-walled carbon nanotube (SWCNT), fullerodendron, and SiO(2) shows high-efficiency light-driven hydrogen evolution from water. Upon visible light irradiation, SWCNT/fullerodendron/SiO(2) coaxial nanohybrid shows hydrogen evolution activity in the presence of methyl viologen (MV(2+)), benzyldihydronicotinamide (BNAH), and a colloidal polyvinyl alcohol(PVA)-Pt. 相似文献
90.
To functionalize the surface of nanoparticles with phenyl groups for subsequent cross-linking with aromatic molecules by mutual interactions, we prepared functional nanoparticles (d = 3 nm) by silanization with phenyl-triethoxysilane. The nanoparticles had Fe(2)O(3) cores conjugated to phenyl groups; this was confirmed by Fourier transform infrared (FT-IR) spectroscopy and absorption spectrophotometry. The typical C-H and C-C peaks and the absorption at 240 nm, which corresponds to aromatic rings, were detected in the spectroscopic results for the phenyl group-modified nanoparticles. The nanoparticles could ionize aromatic (colchicine, reserpine, and bradykinin peptide) and nonaromatic (L-α-phosphatidylethanolamine,dioleoyl, and polyethylene glycol) molecules by nanoparticle-assisted laser desorption/ionization mass spectrometry. The nanoparticles worked as a selective trap and an ionization-assisting reagent in mass spectrometry for the aromatic molecular targets. 相似文献