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121.
M. Ueshima K. Sano M. Ikeda K. Yoshino J. Okamura 《Research on Chemical Intermediates》1998,24(2):133-141
The selective catalytic oxidation (SCO) of ammonia to N2 was studied by using a series of noble metal-V2O5-WO3 catalysts supported on titania-silica (TS) prepared by coprecipitation method. In the V2O5-WO3 catalyst system, the use of TS as a support was very effective to enhance catalytic activity compared with TiO2 or SiO2 alone. The addition of a slight amount of Pd and Ir to V2O5-WO3/TS catalyst caused also remarkable enhancement of the catalytic activity without decreasing the selectivity to N2. The present catalysts provide remarkably high catalytic performance for SCO of ammonia to N2 under the practical reaction conditions for an industrial application. 相似文献
122.
Takahiro Makino Kimihiko Kato Hiroyuki Lyozumi Hiroe Honzawa Yoshiaki Tachiiri Mitsuo Hiramatsu † 《Photochemistry and photobiology》1996,64(6):953-956
Abstract— Ultraweak luminescence generated by sweet potato and nonpathogenic Fusarium oxysporum interactions associated with a defense response was detected by a photoncounting method using ultrahigh-sensitive photodetectors. The time-dependent intensity variation, the spectrum and the two-dimensional imaging of the ultraweak luminescence are indicative of the defense response of the sweet potato to F. oxysporum. The production of ipomeamarone as a phytoalexin means that F. oxysporum induced the defense response in the sweet potato. 相似文献
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126.
Yoshihiko Taguchi Yasuyuki Ishida Hajime Ohtani Hiroyuki Bekku Masaya Sera 《Analytical sciences》2004,20(3):495-499
A polymeric hindered amine light stabilizer (HALS), Tinuvin 622 (MW [symbol: see text] 4000), in PP materials formulated with a magnesium hydroxide flame retardant was determined by reactive thermal desorption (RTD) gas chromatography (GC). Two kinds of the HALS components that were formed through the RTD in the presence of tetramethylammonium hydroxide [(CH3)4NOH, TMAH] were clearly observed in the chromatograms of the PP samples, with negligible interference from the other additives and the PP substrate. Here, the coexisting flame retardant was proved to affect significantly the RTD process of the occluded HALS. As a result, the recovery of the HALS components in the RTD-GC chromatograms of the PP samples increased with increase in the content of the flame retardant. This enhancement of the HALS recovery is attributed mainly to the preferential exposure of the HALS on the surface of the ground PP sample through the interaction between the polymeric HALS and the flame retardant in the molten PP during kneading. In spite of such a considerable action of the flame retardant, the observed intensities of the characteristic peaks of HALS by RTD-GC showed a good linear relationship with the HALS content in the PP samples with constant content of the flame retardant (50 phr); this relationship could be used as the calibration line for the determination of the polymeric HALS in the PP materials containing the flame retardant. 相似文献
127.
The synchronized self-motion of two camphor boats on polygonal water chambers was investigated. The two boats synchronously moved depending on the number of corners in the polygon by changing the distance between the two boats through the corners. We regard the self-motion of a camphor boat as an oscillator; i.e., one cycle on the polygonal chamber corresponds to 2pi. Phase-locked synchronization at a phase difference of 2pi/3, which corresponds to the length of one side of the chamber, was observed with a triangular chamber. Two types of synchronized motion at phase differences of pi/2 and pi, which correspond to the length of one and two sides of the chamber, respectively, were observed with a square chamber. These characteristic features of synchronized self-motion were qualitatively reproduced by a numerical calculation that regarded the surface tension as the driving force and the number of corners in the chamber as a velocity-regulating mechanism. We believe that the present system may be a simple model of synchronization which depends on the geometry of the system. 相似文献
128.
Komatsu T Hayakawa S Tsuchida E Nishide H 《Chemical communications (Cambridge, England)》2003,(1):50-51
alpha-Cyclodextrin (alpha CD)-penetrating 2-methyl-1-phenethylimidazole coordinates to the zinc(II) and iron(II) complexes of meso-tetrakis[o-(N-methyl)pyridinium] porphyrinate, giving non-covalently linked alpha CD-porphyrin ensembles; the iron(II) complex can reversibly bind and release dioxygen in aqueous DMF solution. 相似文献
129.
The origin of Cotton effect shown by o-nitrobenzoyl esters is discussed. The Cotton effect observed for 1-(?)-methyl ester of 3-nitrophalic acid and 4-nitrohemimellitic acid (6 and 12), indicated that the favoured twisting direction of the nitrobenzene moiety is determined by the asymmetric menthyl group through the intervening carboxyl groups. This provides a new concept in conformational analysis of aromatic compounds. Extending the concept of conformational transmission to 2,2′-dinitrobipenhyl derivatives with known ab twisted nitrobenzene was related to the sign of the Cotton effect at 330 nm in accordance with the result of X-ray crystal analysis 1-(?)-menthyl 4-bromo-2-nitrobenzoate (1) 相似文献
130.
Jan F. Biernat Maria Bochenska Jerald S. Bradshaw Hiroyuki Koyama Gypzy Lindh John D. Lamb James J. Christensen Reed M. Izatt 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(6):729-738
Five new macrocyclic ligands each containing two sulfonamide groups have been prepared. Three of these compounds contain one or two chloro substituents and the other two have one or two pyridine subcyclic units. A seventeen-membered ring ligand (4) was found to be an excellent transport agent for all alkali metal cations in a water-methylene chloride-water bulk liquid membrane system when the pH of the source phase was 13 or higher. The chlorine-substituted analog (5) was a poor transport agent for the alkali metal cations possibly because the chlorine atom blocked entry to the macrocycle cavity. An open-chain analog containing two sulfonamide groups was particularly effective in transporting cesium ions. 相似文献