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571.
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T. Fukuda M. Ishihara H. Ogata I. Miura T. Shimoda K. Katori S. Shimoura M.-K. Tanaka E. Takada T. Otsuka 《Nuclear Physics A》1984,425(3):548-572
Nonequilibrium light-particle emissions have been investigated in the reaction 93Nb + 14N at 132, 159 and 208 MeV by measuring inclusive differential cross sections of p, d, t, 3He and α. The experimental data were analyzed in terms of three models: (i) an extended exciton model, (ii) a coalescence model, and (iii) a moving thermal source model. The angle-integrated energy spectra of the protons were well described by the extended exciton model in which projectile nucleons were assumed to be transferred to the target one by one, but those of composite particles were not. On the other hand, the composite particle spectra (except for α at forward angles) were successfully described by the coalescence model using spectra consistent with those for the protons. Extracted coalescence radii P0 were about 140 MeV/c for d and t, and about 220 MeV/c for α. The light-particle spectra were also fitted by the moving-source model assuming isotropic emission from a source moving with approximately half of the beam velocity and with much higher temperature than that of the compound nucleus. Extracted temperatures followed the systematics of a recent compilation for the various reactions. A discussion of these analyses is given. 相似文献
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The analysis time for determination of boron in steel can be remarkably shortened by simultaneous distillation of methyl borate and evaporation of the distillate for analysis by ICP atomic-emission spectrometry. Methyl borate, distilled with a large quantity of methanol, is collected in 4% sodium hydroxide solution heated in a water-bath at 90 degrees. As the boiling point of the mixture of absorption solution and methanol is lower than 90 degrees, the solvent mixture is easily evaporated. The limit of detection corresponds to 35 ng of boron in 0.5 g of steel. 相似文献
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Ohne Zusammenfassung 相似文献
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Yoshihisa Kurasawa Muneto Muramatsu Kaoru Yamazaki Setsuko Tajima Yoshihisa Okamoto Atsushi Takada 《Journal of heterocyclic chemistry》1986,23(4):1245-1248
3-(α-Chlorophenylhydrazono-1,3,4-oxadiazol-2-ylmethyl)-2-oxo-1,2-dihydroquinoxalines 4a-d and 3-(α-chlorophenylhydrazono)methoxycarbonylmethyl-2-oxo-1,2-dihydroquinoxalines 5a-c have been clarified to exhibit the characteristic tautomeric equilibria between the hydrazone imine form C and the diazenyl enamine form D with a long-range prototropy by means of the pmr and 13C-nmr spectroscopies. 相似文献