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Masaki Kurokiba Naoto TanakaAtusi Tani 《Journal of Mathematical Analysis and Applications》2002,272(2):448-457
In this paper we consider the Eguchi-Oki-Matsumura equation which consists of the fourth- and second-order coupled equations of parabolic type. It is shown that this system admits the unique global solution. 相似文献
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H. Sato A. Tani A. J. Fielding S. S. Eaton G. R. Eaton N. E. Whitehead M. Ikeya 《Applied magnetic resonance》2004,26(4):601-616
Nitrate radical NO32− in calcitic evaporate was discovered in Antarctica. The distribution and formation of nitrate radical NO32− in the calcite have been studied by pulse and continuous-wave electron spin resonance. In samples that had been annealed
to destroy the NO32−, regeneration of the radical by γ-rays or UV light indicated that the radical was formed by UV light (with wavelengths less
than 340 nm) from solar rays, not by environmental radiation. The nonuniform spatial distribution of the nitrate radical,
which was deduced from high ratios of local spin density to total spin density, suggests that the nitrate impurity was introduced
into the calcium carbonate after carbonate grain formation. Formation of the carbonate-containing nitrate requires the presence
of high amounts of nitrate and a dry climate. Formation of the nitrate radical requires sample exposure to UV light. These
conditions are satisfied in the environment of Antarctica. 相似文献
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An interesting transformation occurs during acylation of 4(R)-hydroxymethyl-3-methyl-1,3-thiazolidine when 4(R)-acylthiomethyl-3-methyl-1,3-oxazolidines are yielded: the reaction competing with O-acylation is controlled by the bulkiness of the acyl group. 相似文献
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The magnesium-butadiene 1 : 1 (1), 1 : 2 (II) and 1 : 3 addition compounds obtained by the direct metalation of butadiene with metallic magnesium were isolated. These compounds have a polymeric structure. Structural analysis of these compounds by NMR and IR methods was carried out. The process for the formation of II via I and III via II was investigated. The results of protolysis and alkylation of the above magnesium compounds corresponded well to those of crotylmagnesium compounds. 相似文献
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Mechanism for polymerization of ε-caprolactam in the presence of both sodium and aluminum caprolactamate was investigated at 171°C. The role of Al(Cap)3 as an initiator was revealed. The apparent rate constant of propagation reaction decreased with the increase in the concentration of Al(Cap)3, as the two different metal salts interact even at 171°C. The activation energy of the overall polymerization reaction with this catalyst system was estimated to be 41.18 kcal/mole. 相似文献