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41.
Anna Polishchuk Tatyna Emelina Emilya Karaseva Oana Cramariuc Vladimir Chukharev Vladimir Karasev 《Photochemistry and photobiology》2014,90(1):79-84
The effect of intermolecular proton transfer on the spectral properties of levofloxacin in the ground and excited electronic states was studied. The preferred direction of possible protolytic reactions induced by UV irradiation in this compound was studied. It was found that the proton transfer processes have a considerable effect on the capability of the compound to emit light and occur on the nanosecond timescale. The photochemical reactions of the tree forms of levofloxacin (pH: 4.0, 7.0, 10.0) were studied by laser flash photolysis and product studies. Irradiation at pH 4 yielded a pulse and transient (λmax = 395, 515, 575 nm) assigned to the protonated triplet. Irradiation at pH 7 yielded a transient species (λmax = 525, 610 nm) assigned to the neutral form. Protonation of the anionic singlet excited state was also observed (λmax = 440, 570, 680 nm). 相似文献
42.
A. V. Polishchuk E. T. Karaseva A. I. Cherednichenko A. V. Gerasimenko V. E. Karasev 《Russian Journal of Coordination Chemistry》2011,37(3):215-222
The complex (CfqH2AuCl4 · H2O ((CfqH2)+ is the ciprofloxacinium cation) was isolated and analyzed by spectral luminescence, X-ray photoelectron spectroscopy, and X-ray diffraction analysis. The central Au(III) atom has no direct interatomic contacts with the 1-cyclopropyl-6-fluoro-4-oxo-(1-piperazinyl)-1,4-dihydro-3-quinolinecarboxylic acid (CfqH) molecule. The structure is formed by the [AuCl4]? anions having a square structure, (CfqH2)+ cations, and water molecules combined by hydrogen bonds. The protonation of CfqH occurs at the terminal nitrogen atom of the piperazinyl group. Core-level X-ray photo-electron spectra of carbon, oxygen, nitrogen, and fluorine were measured. Cleavage of the Su-Cl bond was shown to be the primary step of the photoinduced decomposition of the compound. 相似文献
43.
R. N. Karasev 《Discrete and Computational Geometry》2011,45(2):340-347
In this paper we consider some results on intersection between rays and a given family of convex, compact sets. These results
are similar to the central point theorem, and Tverberg’s theorem on partitions of a point set. 相似文献
44.
Dorofeeva OV Mitin AV Altova EP Karasev NM Nabiev OG Vilkov LV Oberhammer H 《Physical chemistry chemical physics : PCCP》2011,13(4):1490-1498
Gas-phase electron-diffraction data and high-level quantum chemical calculations have been used to study the conformational behaviour of N-azidomethylpyrrolidine. The two most stable conformers with a relative abundance of about 80% at 298 K possess gauche orientation of the azidomethyl group around the C-N(pyr) bond (C-N(azido)gauche with respect to the endocyclic N(pyr)-C bond). This orientation is a strong manifestation of an anomeric effect. The influence of the anomeric effect is also reflected in shortening of the C-N(pyr) bond and lengthening of the C-N(azido) bond as compared to such bonds in other compounds. 相似文献
45.
M. V. Karasev 《Mathematical Notes》1996,60(6):703-707
Translated fromMatematicheskie Zametki, Vol. 60, No. 6, pp. 930–934, December, 1996. 相似文献
46.
47.
V. P. Karasev 《Journal of Russian Laser Research》1991,12(2):147-164
A general approach is formulated for analyzing algebraic models of quantum composite systems with an internal symmetry described by group G. The case G = SU(2) is examined in detail as applied to the analysis of polarization invariance in quantum optics. A new class of fully depolarizable quantum states of light (scalar biphotons) is defined and investigated. Certain interactions of scalar biphoton light with material media are considered in the context of Dicke and Jaynes-Cummings models.Landsberg Optics Division, Lebedev Physics Institute. Translated from Preprint No. 137 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1990. 相似文献
48.
We consider a model of particle motion in the field of an electromagnetic monopole (in the Coulomb-Dirac field) perturbed by homogeneous and inhomogeneous electric fields. After quantum averaging, we obtain an integrable system whose Hamiltonian can be expressed in terms of the generators of an algebra with polynomial commutation relations. We construct the irreducible representations of this algebra and its hypergeometric coherent states. We use these states to represent the eigenfunctions of the original problem in terms of the solutions of the model ordinary differential equation. We also present the asymptotic approximations of the eigenvalues in the leading term of the perturbation theory, where the degeneration of the spectrum is removed completely.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 142, No. 1, pp. 127–147, January, 2005. 相似文献
49.
E. S. Dzlieva A. Yu. Ivanov V. Yu. Karasev A. I. Éĭkhval’d 《Optics and Spectroscopy》2006,101(5):816-821
The melting of a dusty plasma structure formed in a stratum of a glow discharge caused by application of a magnetic field and its subsequent increase is studied. The images of two-dimensional cross sections of dusty plasma structures previously obtained by the authors are considered. To identify the phase, the correlation functions are calculated and visual comparison with the space lattices of ideal crystals is performed. It is found that, under the conditions of the previous study of the authors, as the magnetic field increases, the phase state of the dusty structure changes from an anisotropic liquidlike (liquid-ice) state to a disordered one. There is a tendency to a change in the type of the space lattice of the structure. 相似文献
50.
Various aspects of the calculus of functions of ordered self-adjoint operators are considered. Passage to the commutative limit in the case of general nonlinear commutation relations is studied. An asymptotic solution of the Cauchy problem and asymptotically self-similar solutions are constructed for unitary-nonlinear operator equations. Asymptotic solutions are found for the Hartree equation with Coulomb interaction.Translated from Itogi Nauki i Tekhniki, Sovremennye Problemy Matematiki, Vol. 13, pp. 145–267, 1979. 相似文献