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1.
The constants of binding dye molecules with the micelles of sodium dodecyl sulfate are determined using quenching of delayed fluorescence of acridine dyes by sodium iodide in aqueous–micellar solutions. Kinetic equations have been composed that describe the processes of deactivation of the excited states of dyes. By solving these equations at the concentration of the quencher sodium iodide corresponding to the minimum lifetime of triplet states and at the concentration of micelles corresponding to the least value of the delayed fluorescence quenching rate constants, we obtained the constants of binding dyes with micelles equal to 1.3·107, 2.9·107, and 3.1·107 M–1 for trypaflavine, acridine orange, and acridine yellow, respectively. We calculated the rate constants of quenching of the triplet states of the molecules of dyes by iodide ions (I
–) that decreased in transition from trypaflavine to acridine orange and acridine yellow. 相似文献
2.
V. K. Mel'nikov 《Communications in Mathematical Physics》1991,137(2):359-381
It is shown that the nonlinear Schroedinger equation with a self-consistent source admits investigation by the inverse scattering method for the Dirac operator. The conditions are found under which the solutions of the nonlinear Schroedinger equation with a self-consistent source describe the creation and annihilation of solitons. 相似文献
3.
4.
Barmin M. I. Chekrenev S. A. Kartavykh V. P. Mel'nikov V. V. 《Russian Journal of General Chemistry》2003,73(3):482-487
Procedures for synthesis of coordination compounds of copper(II) with bis(5-amino-1,2,4-triazol-3-yl)alkanes as ligands. A conclusion was drawn that the coordination polyhedron of copper(II) has different configurations depending on the structure of the ligand and on the coordination mode. 相似文献
5.
It was found that the interaction of the modified paramagnetic defects SiO(CH2)
n
H2 (n = 0.1) with nitromethane on a thermochemically activated silica surface at 300 K results in the formation of the following nitroxyl radicals: SiO(CH2)
n
CH2ON(
)CH3 and SiO(CH2)
n
CH2N(
)CH3. It was suggested that these radicals are the products of two different reactions of the modified paramagnetic defects: the first results from a reaction with free nitromethane; the second, from a reaction with nitromethane bound as complexes with diamagnetic surface defects. 相似文献
6.
The reactions of aliphatic β-amino-β-trifluoromethylvinyl ketones with an excess of ethylenediamine at room temperature afforded
the corresponding 2,3-dihydro-1H-1,4-diazepines or substituted 2-acetonyl-2-trifluoromethylimidazolidines (the latter were obtained when the approach to the
carbonyl group was sterically hindered).
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2305–2308, November, 1998. 相似文献
7.
A. F. Prokof'eva Zh. Z. Sapozhnikova V. N. Volkova V. V. Negrebetskii L. A. Pokrovskaya N. N. Mel'nikov 《Chemistry of Heterocyclic Compounds》1991,27(7):772-778
A study was carried out of alkylation, acylation and aminomethylation reactions were studied in the 5-alkyl-4,5-dihydro-1,2,4-triazin-4-one series. Alkylation by alkyl halides proceeds in the presence of sodium methylate at the N
(1)
and N
(4)
atoms with the formation of a mixture of alkylated compounds of three types: derivatives of 4,5-dihydrotriazine, unsaturated triazine, and their dimers. Acylation with isocyanates leads to the formation of heterocyclic ureas — derivatives at the N
(4)
atom. Mono- and bisaminals were obtained by the reaction of triazines with ethoxymethyldiethylamine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 963–970, July, 1991. 相似文献
8.
An analog of N. N. Bogolyubov's theorem is proved concerning averaging, on a finite time interval, of a system of integral-differential equations with a Poisson noise.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 43, No. 2, pp. 273–277, February, 1991. 相似文献
9.
M. A. Pervozvanskaya M. S. Pevzner L. N. Gribanova V. V. Mel'nikov B. V. Gidaspov 《Chemistry of Heterocyclic Compounds》1977,13(12):1335-1337
The dipole moments of indazole and a number of its nitro derivatives in dioxane solution were measured. The directions of the vectors of the dipole moments of indazole in the tautomeric 1-H and 2-H forms were determined to solve the problems associated with the tautomerism and the position of the substituents in the molecules. The experimental values of the dipole moments, of the investigated compounds were compared with the values calculated via a vector additive scheme. As a result it was shown that the mononitro and dinitro derivatives of indazole exist primarily in the 1-H tautomeric form, whereas the trinitro and tetranitroindazoles exist in the 2-H tautomeric form. The ratios of the isomers were calculated for compounds that have dipole moments intermediate between the 1-H and 2-H forms. A deviation between the experimental and calculated dipole moments of compounds containing two nitro groups in the ortho position was established; this may be explained by disruption of the coplanarity of the molecules or by deviation from additivity because of the introduction of strong electron-acceptor substituents.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1669–1671, December, 1977. 相似文献
10.
Metallosilicates as supports of Co catalysts for the synthesis of liquid hydrocarbons from CO and H2
A. Yu. Krylova A. L. Lapidus M. P. Kapur V. I. Vershinin V. B. Mel'nikov 《Russian Chemical Bulletin》1993,42(3):432-434
The effect of the nature of the silicate support on the activity and selectivity of 10%. Co/M silicate catalysts (where M=Cu, Zn, Ce, Ti, Hf, La, Al, Zr, Co, Mg) in the synthesis of hydrocarbons from CO and H2 has been established. Co and Zr catalysts have been shown to provide the highest catalytic efficiency. The yield of liquid hydrocarbons in their presence exceeds 120 g m–3.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 480–482, March, 1993. 相似文献