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111.
Munehiko Itō 《Topology and its Applications》1985,19(1):65-69
Let X be an M3-space. If every point of X has a closure preserving outer base, then X is an M1-space. This is a remarkable improvement on [2, Corollary 2.8]. If there is a point of X having no closure preserving outer base, then we have an M3-space which is not M1. 相似文献
112.
113.
M. Kicińska-Habior P. Decowski M. Dąbrowska W. Grochulski P. Jaracz T. Matulewicz B. Sikora J. Tōke E. Somorjai 《Zeitschrift für Physik A Hadrons and Nuclei》1983,312(1-2):89-93
Differential cross sections forγ-transitions to 12 states in28Si following nonresonant proton capture in27Al nuclei (E p=1,625 keV) were measured and analysed in terms of the direct-semidirect model. The experimental data are reproduced only when the complex coupling constant with the GDR is enhanced for thef partial wave in the entrance channel. 相似文献
114.
A remarkable characteristic of the thermal expansion coefficient is reported in respect of its temperature and pressure dependences. Then, on the basis of the mixture model, important predictions are derived on the properties and structure of water under high pressures. 相似文献
115.
116.
117.
In the electrodialysis process for concentrating sea water, the addition of a small amount of the polycationic reagent Nonisold into the sea water feed results in a reduction of divalent cation permeability relative to that of monovalent cations. This is due to the formation of a reagent layer on the surface of the cation-exchange membrane. Divalent cations require greater energy to pass over the potential barrier at the reagent layer than do monovalent cations. The relationship between the height of the potential barrier and the ratio of ionic fluxes or the permselectivity coefficient is deduced on the basis of a kinetic-controlled mechanism of uptake of ions from the solution, and the height of the potential barrier is estimated from the experimental results. The difference between the potential barrier for divalent cations and that for monovalent cations may reach up to about 10 kJ/mol. 相似文献
118.
Such an asymmetric [2,3]-Wittig variant that is both highly enantio- and erythro-selective is described within the context of the chiral synthesis of the insect pheromones, (3, 4)-4-methyl-3-heptanol and ()-4-methyl-3-heptanone. 相似文献
119.
Yoshiharu Matsubara Toshikazu Uchida Takashi Ohnishi Koichi Kanehira Yoshiji Fujita Tsuneaki Hirashima Ikuzo Nishiguchi 《Tetrahedron letters》1985,26(37):4513-4516
Anodic oxidation in acetic acid of polycyclic cyclopropanes, namely tricyclene, cyclofenchene, and longicyclene, followed by hydrolysis brought about stereo- and regioselective formation of the corresponding homoallylic alcohols as the main product in good yields. 相似文献
120.
A comparative study is made for Λc5He and Λc9Be charmed nuclei versus Λ5He and Λ9Be hypernuclei. The Λc(Λ)+α and Λc(Λ)+α+α systems are treated in a microscopic way. Within certain range of the ΛcN interaction strength, the energy properties of Λc+α and Λc+α+α are calculated and discussed. Similarity between the energy spectra of the noted charmed nuclei and hypernuclei is suggested. 相似文献