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81.
Volodymyr M. Prokip 《Journal of Mathematical Sciences》2011,174(4):481-485
The necessary and sufficient conditions of diagonalization of matrices over a domain of principal ideals with minimal polynomial m(??) = (?? ? ??)(?? ? ??), ?? ?? ?? are obtained. On the basis of the obtained results, the conditions under which the matrices have common eigenvectors are indicated. 相似文献
82.
83.
84.
We study the structure of the semigroup IO n of all order-preserving partial bijections on an n-element set. For this semigroup we describe maximal subsemigroups, maximal inverse subsemigroups, automorphisms and maximal nilpotent subsemigroups. We also calculate the maximal cardinality for the nilpotent subsemigroups in IO n which happens to be given by the n-th Catalan number. 相似文献
85.
V. A. Sadykov S. A. Beloshapkin E. A. Paukshtis G. M. Alikina I. Kochubei S. P. Degtyarev N. N. Bulgakov S. A. Veniaminov V. Netyaga R. V. Bunina A. N. Kharlanov E. V. Lunina V. V. Lunin V. A. Matyshak A. Ya. Rozovskii 《Reaction Kinetics and Catalysis Letters》1998,64(1):185-191
Transformation of surface nitrates under CH4 (CH4+O2) was found to ensure steady-state activity of Co-ZSM-5 in the selective catalytic reduction of nitrogen oxides by methane
(CH4-SCR). For Cu-ZSM-5, such species are mainly converted into NO. Relaxation of the coordination sphere due to oxygen and NO
adsorption, stability of C,N-containing intermediates and activation routes of hydrocarbons (methane, propane) were analyzed
as factors determining catalytic properties of Cu and Co cations. 相似文献
86.
87.
V. I. Kelarev S. G. Shvekhgeimer V. N. Koshelev G. A. Shvekhgeimer A. F. Lunin 《Chemistry of Heterocyclic Compounds》1984,20(7):721-723
The condensation of hydrochlorides of ethyl iminoesters of 4-hydroxy-3,5-di-tert-butylbenzoic and -(4-hydroxy-3,5-di-tert-butylphenyl) propionic acids with monoethanolamine, o-aminophenol, and o-phenylenediamine was studied. As a result, 2-oxazolines, benzoxazoles, and benzimidazoles containing sterically hindered phenol residues in the 2-position were synthesized.For Communication 34, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 889–892, July, 1984. 相似文献
88.
I. Yu. Kaplin E. S. Lokteva E. V. Golubina K. I. Maslakov S. A. Chernyak A. V. Levanov N. E. Strokova V. V. Lunin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(11):2157-2164
The catalytic activity in CO oxidation of Ce x Zr1–x O2 double oxides prepared using pine sawdust and cetyltrimethylammonium bromide (CTAB) as templates is compared. It is found by means of SEM and the low-temperature adsorption of N2 that biomorphic oxides reproduce the macropore structure of the template. It is shown via XRD and Raman spectroscopy that all samples contained mixed ceria-zirconia oxide. The double oxides form a cubic phase with a lattice of the fluorite type at a ratio of Ce: Zr = 4, regardless of the nature of the template; when Ce: Zr = 1, the biomorphic mixed oxide forms a tetragonal phase. According to Raman spectroscopy and XRD it was shown that the distortion of the oxygen sublattice is higher in biomorphic samples. Energy dispersive analysis shows that Ca impurities were present in the biomorphic samples, introducing additional distortions in the lattice of double oxide and leading to the formation of anionic vacancies. It is found that when Ce: Zr = 4, the conversion of CO on biomorphic oxide in the range of 100–350°C is higher than that observed for Ce x Zr1–x O2 (CTAB); reducing the Ce: Zr ratio in the biomorphic sample to 1 results in a marked decrease in CO conversion at 100–200°C. It is concluded that these differences are due to changes in the mobility of the lattice oxygen. 相似文献
89.
Malets Yehor S. Moskvina Viktoriia S. Grygorenko Oleksandr O. Brovarets Volodymyr S. 《Chemistry of Heterocyclic Compounds》2019,55(11):1007-1012
Chemistry of Heterocyclic Compounds - This minireview highlights known methods for the synthesis of azachromones and azachromanones, including the earliest and the latest examples of their... 相似文献
90.
Tolkachev N. N. Koklin A. E. Laptinskaya T. V. Lunin V. V. Bogdan V. I. 《Russian Chemical Bulletin》2019,68(8):1613-1620
Russian Chemical Bulletin - Dynamic light scattering and size exclusion chromatography were used to investigate the size of sodium lignosulfonate particles in water—ethanol media and the... 相似文献