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1.
V. V. Shelkovnikov Z. M. Ivanova N. A. Orlova T. N. Gerasimova A. I. Plekhanov 《Optics and Spectroscopy》2002,92(6):884-891
The formation and properties of J-aggregates in thin solid films of pseudoisocyanines with long N-alkyl groups, obtained by centrifuging from solutions in organic solvents, were studied. It is shown for the first time that nonsymmetric cyanine dyes, containing a C2H5 group at one nitrogen atom and a C10H21, C15H31, or C18H37 group at another nitrogen atom, spontaneously form J-aggregates stable at room temperature and pressing a narrow absorption band with a half-width at half maximum of 200 cm?1. The thermal stability of J-aggregates in thin films of pseudoisocyanines with alkyl substituents decreases in the following order: C2H5-C2H5> C2H5-C6H13>C2H5-C18H37>C2H5-C10H21>C2H5-C15H31. By introducing 1-octadecyl-2-methylquinolinium iodide in the film, it was found that the J-aggregates studied consist of a small number (2–4) of dye molecules. 相似文献
2.
T. M. Varlamova G. V. Gerasimova S. P. Mushtakova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(10):1671-1675
The solubility diagrams of the potassium iodide-water-N,N-dimethylformamide (DMFA) and iodine-iodide-water-N,N-dimethylformamide systems were studied at 25°C by the method of sections. The systems are characterized by three-phase equilibria of the peritonic and eutonic types, respectively. Potassium iodide in the I2-KI-/H2O-DMFA (95: 5 wt %)/ system was found to salt in crystalline iodine. The selected composition of the H2O-DMFA mixed solvent possessed a higher iodine-solving ability compared with pure mixture components. 相似文献
3.
4.
Conditions for the precipitation of phosphates from solutions of titanium(IV) sulfate containing iron(III) were studied. The precipitation of components and the mechanism of the phase formation in the system under study were considered in relation to the TiO2 : Fe2O3 ratio in the starting solution. 相似文献
5.
I. G. Abramov A. V. Smirnov L. S. Kalandadze N. P. Gerasimova N. A. Nozhnin V. N. Sakharov 《Chemistry of Heterocyclic Compounds》2005,41(2):238-240
New 3-aryl-substituted [1,2,4]triazolo][3,4-b][1,3]benzothiazole-6,7-dicarbonitriles have been synthesized by successive interaction of 5-aryl-4H-triazole-2-thiols with 4-bromo-5-nitrophthalonitrile in the presence of K2CO3 initially at the bromine atoms and then at the nitro group.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, 270–272, February, 2005. 相似文献
6.
The rate of cyclization of pentafluoro- (1) and 4-Cl-2,3,5,6-tetrafluoro-2-NHY-diphenyl ethers (2a, Y=Ac;2b, Y=H;2c, Y=Me) to form phenoxazines on refluxing in DMF increases with an increase in the nucleophilicity of the amino group. The cyclization of the N-acetyl derivative2a is followed by the Smiles rearrangement, whereas the transformation of ethers2b andc, containing free amino and N-methylamino groups, respectively, includes mainly an attack on the amino group at theortho-position of the fluorinated ring. In the case of ether2c, introduction of K2CO3 into the reaction mixture results in cyclization with the Smiles rearrangement.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1101–1105, June, 1993. 相似文献
7.
L. N. Sycheva G. F. Gerasimova M. S. Gaisinovich A. N. Ketov 《Reaction Kinetics and Catalysis Letters》1977,7(2):127-132
It has been shown that in the interaction of zinc oxide and phosgene, the most active are the samples having oxygen vacancies. A mechanism for this process is suggested.
, , . .相似文献
8.
I. V. Lazareva L. G. Gerasimova R. F. Okhrimenko M. V. Maslova 《Russian Journal of Applied Chemistry》2006,79(1):16-19
The kinetics of titanium(IV) extraction from sphene with boiling 4–6 M sulfuric acid was studied. The rate constants of the sphene dissolution were determined. The influence of the particle size of the starting mineral on the rate of its dissolution was established. The feasibility of performing sphene dissolution by a liquid-phase procedure yielding stable titanium-containing sulfate solutions suitable for the synthesis of multifunctional composite materials was examined. 相似文献
9.
Tatiana G. Gerasimova 《Linear algebra and its applications》2012,436(9):3777-3783
We give several criteria of unitary similarity of a normal matrix A and any matrix B in terms of the Frobenius and spectral norms, characteristic polynomials, and traces of matrices. 相似文献
10.
By the method of neutron diffraction, the structural changes in 2TeO2·V2O5 glass, arising as a result of reactor irradiation with ~1018n/cm2 fast neutrons flux are investigated. A reduction of the coordination number of the Te atoms, as well as rupture of a part of the 0-0 bonds is observed. 相似文献