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991.
The effect of the central metal of columns packed with silica gels binding Ni(2+)- and Cu(2+)-phthalocyanine derivatives (Ni-and Cu-PCS(D)s) on the retention behavior of poly-aromatic-hydrocarbons (PAHs) thereof in a polar eluent was examined. The retention factors of PAHs on the Ni- and Cu-PCS(D)s in 80% methanol showed a good linear correlation. The Cu-PCS(D) column exhibited the pi-pi interactions for PAHs, while the Ni-PCS(D) column exhibited the pi-d interactions for PAHs in addition to the pi-pi interaction for PAHs. Further, an investigation of the retention behavior of anthracene derivatives having different substituents revealed that the Ni- and Cu-PCS(D) columns could recognize the differences of substituents only in a polar eluent.  相似文献   
992.
We have fabricated a fuel cell based on the DNA film (DNAFC) and examined its properties under various humidity conditions at room temperature. The open-circuit voltage of a DNAFC is generated by supplying H2 gas to the anode. The open-circuit voltage strongly depends on the humidity conditions, and in a DNA film, the optimum condition in which the open-circuit voltage attains a value as high as 0.55 V is achieved under the relative humidity condition of 55%. Furthermore, the cell voltage of the DNAFC decreases with an increase in current density, as observed in fuel cells such as proton exchange membrane fuel cell, solid oxide fuel cell, and several others. These results indicate that DNA film can be used as the fuel cell electrolyte under approximately 55% humidity condition.  相似文献   
993.
The orientation behavior of polystyrene‐block‐hydrogenated polyisoprene‐block‐polystyrene (SEPS) with cylindrical microdomains of polystyrene (PS) dispersed in the rubbery segments was investigated by simultaneous measurements of stress and birefringence during uniaxial stretching. The stress increased sharply with strain below the yield strain and then it gradually increased. In contrast, the birefringence changed little below the yield strain, increased sharply with strain above the yield strain up to a strain of 0.5, and then gradually increased. The characteristic birefringence behavior is attributed to the form birefringence induced by the orientation and the parallel arrangement of the cylindrical microdomains associated with the orientation of the rubbery segments. The orientation function of the cylindrical microdomains f evaluated by analyzing the form birefringence agrees well with that obtained from the SAXS result. The f was almost zero below the yield strain and it increased sharply with strain up to a strain of 0.5 and then was constant above a strain of 0.5. These results suggest that the orientation of the cylindrical microdomains occur above the yield strain up to a strain of 0.5 and that the orientation does not increase above a strain of 0.5 in spite of the continuous orientation of the rubbery ethylene–propylene segments. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 715–723, 2009  相似文献   
994.
The international HypHI collaboration proposes to perform hypernuclear spectroscopy with stable heavy ion beams and rare isotope beams at GSI and FAIR in order to study neutron and proton rich hypernuclei and to measure directly hypernuclear magnetic moments for the first time.The project is divided into four phases.In the first Phase 0 experiment,the feasibility of precise hypernuclear spectroscopy with heavy ion beams will be demonstrated by observing π~- decay channels of ~e_ΛH,~4_ΛH and ~5_ΛHe with ~6Li projectiles at 2 AGeV impinging on a ~(12)C target.In the later Phases 1 through 3,studies of proton and neutron rich hypernuclei,direct measurements of hypernuclear magnetic moments and the spectroscopy of hypernuclei toward the nucleon drip-lines are planned.  相似文献   
995.
α-Allenylcyclopropanedicarboxylates, for which a novel synthetic method has been devised by conjugate addition of a copper hydride (Stryker) reagent to α-cyclopropylpropargylic esters, have been newly found to be smoothly converted to methylenecyclopentene derivatives under mild reaction conditions by further treatment with the copper hydride reagent. The mechanistic pathway is discussed.  相似文献   
996.
997.
Thiosalicylic acid selenotrisulfide(SeT) was prepared by the reaction of thiosalicylic acid and selenious acid in methanol. The precipitated SeT was partially purified by an extensive washing with methanol and pure SeT was isolated by preparative high-performance liquid chromatography (HPLC) using a reverse phase column. The HPLC method was useful both in the analysis and the isolation of SeT.  相似文献   
998.
We have generated thep-cyanobenzyl radical in supersonic free expansion, and measured the vibrationally and rotationally resolved laser induced fluorescence (LIF) excitation spectra and the LIF dispersed spectra from the single vibronic levels (SVL) in the green-blue region. The lowest energy band at 20 738 cm−1with the strongest intensity in the excitation spectrum has been assigned to the 000band of the visible spectrum, on the basis of the vibronic structures in the SVL dispersed spectra. Based on the band type of the 000band,a-type, determined from the rotationally resolved LIF excitation spectrum, we have definitely assigned the visible band to theD122B1–D012B1electronic transition. We have found, on the grounds of the vibrational analysis of the dispersed spectra, that the vibronic structure of the 22B1–12B1electronic transition of the benzyl type is characterized by totally symmetric fundamental modes, 1, 8a, and 9a.  相似文献   
999.
1000.
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