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51.
Ken Kato Yasuhiro Kasuga Masanori Fujiwara Kazuo Onda 《Electrical Engineering in Japan》1996,116(4):94-108
Laboratory-scale and parametric experiments of SO2 and NOx removal from the simulated combustion gas by pulsed corona discharge have been performed by changing the combustion gas composition and temperature, the electrode configuration of plasma reactor, and the polarity of high-voltage electrode. The following results are obtained: 1) the higher the concentration of H2O and O2, the higher the efficiency of desulfurization and denitrification at the same specific input; 2) the pulsed corona discharge with a voltage pulsewidth as short as 200 ns of negative polarity shows the possibility to attain almost 90 percent deSOx and deNOx efficiency at the specific discharge input of 20 J/g, which is almost the same as the specific input in the electron-beam process; 3) the deNOx characteristics show a little temperature dependence in the range of 70 to 130°C, but the deSOx efficiency increases rapidly in the temperature region below 100°C suggesting the thermochemical dependence of deSOx reaction; 4) when desulfurization and denitrification proceed, the white dendritic powder deposits on the plasma reactor whose composition is identified to be 49 mol% (NH4)2SO4 and 47 mol% of 2NH4NO3 · (NH4)2SO4, and the ratio of SO2, NO and NH3 of the deposit is almost equal to that of supplied gas. 相似文献
52.
A finite element parametric study on the mechanical properties of J-shaped steel hysteresis devices 总被引:1,自引:0,他引:1
Shiro Kato 《Journal of Constructional Steel Research》2006,62(8):802-811
The present paper discusses the mechanical properties of J-shaped steel hysteresis devices, abbreviated to “J-dampers”, interposed between the upper structure of a spatial structure and its substructure. The mechanical properties of a J-damper, which are characterized by its key geometrical and material parameters, are evaluated through parametric analyses using an in-house Finite Element program. The hysteresis behavior of a J-damper is also modeled by a bi-linear elasto-plastic hysteresis model with the strain-hardening effect. Its elastic stiffness, yield strength and dimensionless hardening ratio, which are expressed as functions of the parameters, are formulated on the basis of mathematical models and the results of parametric studies. Finally, some remarks relevant to the application of the proposed hysteresis model are made for the design of the J-damper. 相似文献
53.
Masahito Matsubayashi Takashi Hibiki Kaichiro Mishima Koji Yoshii Koji Okamoto 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2003,510(3):325-333
A fluorescent converter for fast neutron radiography (FNR) comprising a scintillator and hydrogen-rich resin has been developed and applied to electronic imaging. The rate of the reaction between fast neutrons and the converter is increased by thickening the converter, but its opaqueness attenuates emitted light photons before they reach its surface. To improve the luminosity of a fluorescent converter for FNR, a novel type of converter was designed in which wavelength-shifting fibers were adopted to transport radiated light to the observation end face. The performance of the converter was compared with that of a polypropylene-based fluorescent converter in an experiment conducted at the fast-neutron-source reactor YAYOI in the University of Tokyo. 相似文献
54.
We studied the rates of gelation and phase separation of poly(vinyl alcohol) (PVA) solutions in mixtures of dimethyl sulfoxide (DMSO) and water at 25 °C and found that both the rates show a maximum at a volume fraction of DMSO φDMSO=0.60 while gelation was not observed either in pure DMSO or pure water, suggesting that water-DMSO is a cononsolvent system for PVA. On the basis of the data by Cowie [Can J Chem 36 (1961) 2240] we concluded that the 1:2 stable complex between one DMSO molecule and two water molecules is the main cause of this cononsolvency. 相似文献
55.
Susumu Onaka Masaharu Kato T. Mori 《Metallurgical and Materials Transactions A》1986,17(11):1949-1953
Steady-state sliding of grain boundaries is discussed by taking into account the change in the potential energy of an applied
stress, when the sliding occurs by diffusional accommodation. The present analysis enables us to derive the sliding rates
at boundaries of various shapes in a simple manner without knowing local stress fields. Sliding rate of a boundary containing
second phase particles is also derived by similar calculations. The results are compared with previous calculations by other
investigators, and it is found that the resultant expressions for the sliding rates are essentially identical to those derived
from more complex analyses. 相似文献
56.
Formation of dityrosine and other fluorescent amino acids by reaction of amino acids with lipid hydroperoxides 总被引:7,自引:0,他引:7
Formation of fluorescence by the reaction of various amino acids with lipid hydroperoxides,i.e., linoleic acid 13-monohydroperoxide, methyl linoleate 13-monohydroperoxide and phosphatidylcholine hydroperoxide, in the
presence of methemoglobin was investigated. Two types of fluorescence were produced: fluorescent dityrosine (3,3′-dityrosine)
from tyrosine, and unidentified fluorophores with α- and ε-amino groups of various amino acids. While the former was stable
after treatment with borohydride, the latter fluorophores were readily destroyed. The rate of dityrosine formation was rapid,
and the yield of dityrosine was dependent on the concentrations of tyrosine and the lipid hydroperoxides. Butylated hydroxytoluene
and tocopherol inhibited the formation of dityrosine, but did not affect the formation of fluorophores on the amino groups.
Dityrosine appears to be formed by radical reaction of the lipid hydroperoxides, while the other fluorophores seem to be created
by nonradical mechanisms. 相似文献
57.
58.
59.
Keiji Itabashi Takuji Ikeda Akihiko Matsumoto Kunikazu Kamioka Masanao Kato Kazuo Tsutsumi 《Microporous and mesoporous materials》2008,114(1-3):495-506
Four types of Rb-aluminosilicate zeolites were hydrothermally synthesized in pure phase for the first time from Rb-aluminosilicate gels without using any organic structure-directing agent (SDA) under stirring conditions. The crystal structure of each zeolite was refined by Rietveld analysis of the X-ray diffraction (XRD) data. These crystal structures were confirmed to be Rb-mordenite, Rb-merlinoite, a new aluminosilicate zeolite with an ATT framework topology, and Rb-offretite denoted by RMA-1, RMA-2, RMA-3, and RMA-4, respectively. The Si/Al ratio of RMA-1 with an MOR topology varied from 5.3 to 8.0; however, the variation of the Si/Al ratios of the other zeolites was rather small. The crystal system of RMA-2 was tetragonal with space group I4/mmm, where two Rb sites were distributed at the center of an 8-membered ring (MR). On the other hand, two Rb sites in RMA-3 were located at the center of the 8-MR in small two cages. The structure of RMA-4 was identified as the OFF type with a local disorder or defect, which included a small amount of an intergrown ERI phase. 相似文献
60.
Jing-Feng Li Ryuzo Watanabe Bo-Ping Zhang Katsuhiko Asami Koji Hashimoto 《Journal of the American Ceramic Society》1996,79(12):3109-3112
2 mol% Y2 O3 -ZrO2 polycrystals were annealed in water and under vacuum to highlight the effect of the presence of H2 O on the low-temperature degradation transformation. The specimen surfaces with monoclinic phases transformed during annealing in the different environments were analyzed by X-ray photoelectron spectroscopy with special interest on the electron binding energy change of the constituent ions of the 2 mol% Y2 O3 -ZrO2 ceramics after the degradation transformation. It was found that no change occurred for the electron-bonding energies of core levels of zirconium ions after the transformation, whereas Y-OH bonds were formed during annealing in water. This result suggested a possibility that the preferred hydration of yttrium took place at the surface of Y2 O3 -partially-stabilized ZrO2 , which is likely to be the reason for the low-temperature degradation accelerated by the presence of H2 O. 相似文献