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91.
92.
A new set of parameters to describe the behavior of word frequencies in texts is proposed. An analogy between the word frequency distribution and the Bose distribution is suggested, and the notion of “temperature” is introduced for this case. The calculations are made for English, Ukrainian, and the Guinean Maninka languages. A correlation between the language structure (the level of analyticity) and the defined parameters is shown to exist. 相似文献
93.
Yakovenko Georgiy G. Saliyeva Lesya N. Rusanov Eduard B. Donchak Il’ya S. Vovk Mykhailo V. 《Chemistry of Heterocyclic Compounds》2021,57(11):1137-1145
Chemistry of Heterocyclic Compounds - N-Boc-4-aminopyrazole-5-carbaldehydes react with methyl 3,3-dimethoxypropanoate or β-keto esters in acetic acid under reflux to form methyl(ethyl)... 相似文献
94.
Vitalii Nytka Vasyl Kordan Andrij Stetskiv Volodymyr Pavlyuk 《Acta Crystallographica. Section C, Structural Chemistry》2023,79(6):257-262
The ternary Tb2–xNdxZn17–yNiy (x = 0.5, y = 4.83) disordered phase belongs to the structural family based on the rhombohedral Th2Zn17 structure type. The structure is maximally disordered since all the sites are occupied by statistical mixtures of atoms. The Tb/Nd mixture of atoms occupies the 6c site (site symmetry 3m). The statistical mixtures Ni/Zn consisting of more Ni atoms are located in the 6c and 9d (symmetry .2/m) sites. In the following 18f (site symmetry .2) and 18h (site symmetry .m) sites are located Zn/Ni statistical mixtures which consist of more Zn atoms. Zn/Ni atoms form three-dimensional networks with hexagonal channels that fill statistical mixtures of Tb/Nd and Ni/Zn. The Tb2–xNdxZn17–yNiy compound belongs to the family of intermetallic phases capable of absorbing hydrogen. In the structure, there are three types of voids, namely, 9e (site symmetry .2/m), 3b (site symmetry m) and 36i (site symmetry 1), in which hydrogen can be inserted, and the maximum total absorption capacity can reach 1.21 wt% H2. Electrochemical hydrogenation shows that the phase absorbs 1.03% of H2, which indicates partial filling of the voids with H atoms. 相似文献