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251.
252.
Toshiro Hiranouchi 《Comptes Rendus Mathematique》2005,341(4):207-210
We define a certain quotient of the étale fundamental group of a scheme which classifies étale coverings with bounded ramification along the boundary, and show the finiteness of the abelianization of this group for an arithmetic scheme. To cite this article: T. Hiranouchi, C. R. Acad. Sci. Paris, Ser. I 341 (2005). 相似文献
253.
A double column-switching HPLC method with naphthalene-2,3-dialdehyde (NDA) was applied for determination of two plasma antihypertensive peptides, Val-Tyr (VY) and Ile-Val-Tyr (IVY). After a first separation on a Phe-ODS column, double heart-cuts of the retention time corresponding to NDA-VY and NDA-IVY elutions were successfully separated on an analytical ODS column: 60% acetonitrile in 0.1% trifluoroacetic acid containing 5 mM sodium 1-octanesulfonate at 1.0 mL/min. Within-run coefficients of variation were 1.73% and 4.73% for VY and IVY, respectively. 相似文献
254.
O. Kojima T. Isu J. Ishi-Hayase A. Kanno R. Katouf M. Sasaki M. Tsuchiya 《Journal of luminescence》2008,128(5-6):963-965
We report the dynamical properties of the exciton orientation in GaAs thin films using the orientational grating (OG) technique. From the results of excitation-power dependence of OG signal, we confirmed that the OG signal comes from the optical nonlinearity of weakly confined excitons. In addition, the OG-decay time decreases with an increase of excitation power due to exciton–exciton interaction, and the shortest decay time is below 1 ps. Our results may imply the potential application of optical nonlinearity of weakly confined exciton to ultrafast switching devices operating at 1 Tbit/s. 相似文献
255.
Yamanaka T 《Physical review letters》2008,101(13):136101
Active sites for a thermally induced bimolecular two-step catalytic reaction (O2-->2O, O + CO-->CO2) that occurs on a Pt(113)(1 x 2) structure at around 160 K were studied by angular distribution measurements of desorbing product CO2. It was found that the intrinsic activity level of two-atom-wide (001) facets is significantly higher than that of two-atom-wide (111) facets, while the activity of (111) facets was also significant when this reaction was induced by irradiation of 193 nm photons. Possible mechanisms for the difference in activities of the two facets are discussed. 相似文献
256.
Shunji Sugano Charoen Chinwanitcharoen Shigeyoshi Kanoh Toshiro Yamada Shunichi Hayashi Kaoru Tada 《Macromolecular Symposia》2006,239(1):51-57
Aqueous polyurethane dispersions were prepared by the reaction of hydroxyl-terminated poly(ethylene adipate), ethylene glycol, dimethylol propionic acid and aromaic diisocyante, 4,4′-diphenylmethane diisocyanate. The influence of molecular weight of oligoester and molar ratio between isocyanate and hydroxyl groups (NCO/OH) in the prepolymerization step were investigated. Molecular weight, particle size and particle size distribution were measured and compared. It was verified that the molecular weight increases with increasing in NCO/OH molar ratio. The results suggest that the hard segment content plays an important role in particle size and particle size distribution of the dispersions. 相似文献
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259.
The diffusion of three monoanionic dyes [Orange II (C.I. Acid Red 7) and two chromium complex dyes] in nylon 6 is discussed on the basis of dye distribution obtained by the film-roll method. Variations of the diffusion coefficients with dye concentration depend characteristically on the dye species and in one case show a maximum near the dye concentration stoichiometric to the amino endgroup concentration in the nylon. These concentration dependences are interpreted on the assumption of two thermodynamically distinct dye populations in equilibrium. 相似文献
260.