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21.
Single-particle energies E nlj of neutron states in the 28 68 Ni40 nucleus are estimated on the basis of extrapolation of the experimental values of E nlj in the 58,60,62,64Ni isotopes. The data obtained are compared with the results of calculation within the dispersion optical model.  相似文献   
22.
23.
Extrapolation of the single-particle energies E nlj of the bound states of neutrons and protons in the 112,116,118,120,124Sn isotopes has been performed to estimate the values of E nlj for unstable doubly magic 50 100 Sn50 and 50 132 Sn82 nuclei. The estimates obtained are compared with the data derived from the analysis of the decay spectra of neighboring radioactive nuclei and with the results of the calculation within the dispersive optical model.  相似文献   
24.
Single-particle energies of bound neutron and proton states in nuclei with mass numbers 40 ≤ A ≤ 208 are calculated within the dispersive optical model with different sets of global parameters. The results of the calculation are compared with the experimental data and the predictions of the relativistic mean-field model.  相似文献   
25.
Crystallography Reports - The crystal structure and crystallochemical features of a Fe-deficient zirconium-rich analog of eudialyte from the Lovozero alkaline massif (Kola peninsula) have been...  相似文献   
26.
Russian Chemical Bulletin - Hydroxyl-containing compounds (water, methanol, and phenol) act as efficient catalysts of the chain reactions of thiophenol with quinone imines at their propagation...  相似文献   
27.
This study aims to investigate the role of complexation between reagents and the role of solvation of reagents by solvents in the kinetics of chain reactions of quinone imines with thiols. The thermodynamic characteristics of the complexation of quinone imines with thiophenol in CCl4, chlorobenzene, and ethanol, as well as of the complexation of quinone imines and thiophenol with these solvents were calculated by quantum chemical methods (DFT calculations at the PBE/cc-pVDZ level of theory) and in terms of the additive-multiplicative model. Both approaches give consistent results. The formation of molecular complexes in quinone imine–thiphenol systems is accompanied by a 10–30 kJ mol–1 decrease in enthalpy and has only a slight effect on the reaction mechanism.  相似文献   
28.
Reactions of substituted tetrahydropyrrolo[3,2-c]pyridines with dimethyl acetylenedicarboxylate in protic and aprotic solvents were studied. A novel single-step method for the synthesis of pyrrolo[2,3-d]azocine derivatives was developed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2513–2519, November, 2005.  相似文献   
29.
4,5-Dihydro-5-methyl-3H-spiro[benz-2-azepine-3-cyclohexane] N-oxide reacted with cyanide ion and isopropyl magnesium bromide to give the corresponding 1-cyano- and 1-isopropyl-4,5-dihydro-5-methyl-3H-spiro[benz-2-azepine-3-cyclohexane], but reaction with phenyl magnesium bromide, benzyl magnesium chloride, and nitromethane gave cyclic hydroxylamines: 1-substituted N-hydroxy-1,2,4,5-tetrahydro-5-methyl-3H-spiro[benz-2-azepine-3-cyclohexanes] which were oxidized to the corresponding nitrones.  相似文献   
30.
Acylation of 4-α-furyl-4-N-benzylaminobut-1-enes with maleic anhydride gave 4-oxo-3-aza-10-oxatricyclo[5.2.1.01,5]dec-8-ene-6-carboxylic acid via amide formation followed by intramolecular Diels-Alder reaction of furan (IMDAF). The cycloaddition proceeded under mild reaction conditions (25 °C) and provided only the exo-adduct in quantitative yield. Treatment of this compound with PPA gave isoindolo[2,1-b][2]benzazepine derivatives via ring opening, aromatization and intramolecular electrophilic alkylation. In order to extend the scope of the reaction sequence, 7-oxo-5,11b,12,13-tetrahydro-7H-isoindolo[2,1-b][2]benzazepine-8-carboxylic acids were further transformed into useful synthetic intermediates.  相似文献   
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