Photophysical properties and photodynamic activity of octacationic oxotitanium(IV) phthalocyanines

Kuznetsova, Nina,Makarov, Dmitry,Yuzhakova, Olga,Strizhakov, Anton,Roumbal, Yana,Ulanova, Ludmila,Krasnovsky, Alexander,Kaliya, Oleg Korean Society of Photoscience 2009 Photochemical & photobiological sciences Vol.8 No.12

The photophysical and photosensitizing properties of two octacationic oxotitanium phthalocyanines (TiOPcs), bearing pyridiniomethyl or cholinyl substituents, have been studied in aqueous and alcohol solutions. In water, both compounds were monomeric with the high quantum yields of fluorescence (${\Phi}_F$ = 0.17-0.19) and singlet oxygen formation (${\Phi}_\Delta$ = 0.4-0.5). The ${\Phi}_F$ and ${\Phi}_D$ of both phthalocyanines decreased with the increase of solvent hydrophobicity from water to ethanol. This effect was much stronger in alcohol solutions of the pyridiniomethyl-substituted phthalocyanine and probably results from aggregation of TiOPc molecules caused by association of chloride anions with phthalocyanine cationic groups. Evidence is presented that under illumination aqueous TiOPc solutions also produce hydroxyl radicals, which probably appear owing to photocleavage of water molecules. The quantum yield of OH formation was $(3-5){\times}10^{-5}$ after argon purging and twice as much in the presence of air. It is shown that irradiation of TiOPc solutions causes photobleaching of TiOPcs. The photobleaching quantum yield in water was found to be about $1{\times}10^{-4}$. The data suggest that photobleaching occurs owing to the reactivity of hydroxyl radicals, though singlet oxygen is generated by TiOPcs much more efficiently. The phototoxicity of the tested TiOPcs toward bacteria has been revealed. It is proposed that both OH and $^1O_2$ might be responsible for the observed bactericidal effects.

Process of pulsations of the spherical cavity in a liquid under the influence of ultrasonic vibrations

Kuznetsova, Elena L.,Starovoitov, Eduard I.,Vakhneev, Sergey,Kutina, Elena V. Techno-Press 2022 Advances in aircraft and spacecraft science Vol.9 No.2

The paper investigates the process of pulsation of a spherical cavity (bubble) in a liquid under the influence of a source of ultrasonic vibrations. The process of pulsation of a cavitation pocket in liquid is investigated. The Kirkwood-Bethe model was used to describe the motion. A numerical solution algorithm based on the Runge-Kutta-Felberg method of 4-5th order with adaptive selection of the integration step has been developed and implemented. It was revealed that if the initial bubble radius exceeds a certain value, then the bubble will perform several pulsations until the moment of collapse. The same applies to the case of exceeding the amplitude of ultrasonic vibrations of a certain value. The proposed algorithm makes it possible to fully describe the process of cavitation pulsations, to carry out comprehensive parametric studies and to evaluate the influence of various process parameters on the intensity of cavitation.

The Feminist Geopolitics of Donbas: The Role of Art in Challenging Bordering

Irina Kuznetsova 한국외국어대학교(글로벌캠퍼스) 러시아연구소 2021 REGION Vol.10 No.1

Ukrainian art provides unique examples of challenging bordering policies in the geopolitical context of the war in Donbas. Employing critical borders studies and the perspective of feminist geopolitics, this paper looks at borders beyond territories, including discursive landscapes of power and intersection- ality. It focuses on the role of art in post-Maidan Ukraine as a response to political violence and bordering, and the relations between art and bordering work in nongovernment-controlled areas of eastern Ukraine. It argues that feminist art, through practices of “seeing as a border,” brings a more intimate geopolitical perspective to audiences’ understandings of the lived experiences of civilians residing in the nongovernment territories of Donetsk and Luhansk oblasts. Through analysis of Alevtina Kakhidze and Maria Kulikovska’s art, the research demonstrates how the geographical gaze towards art and its role in dis-bordering add to the understanding of space and resistance.

Verification of mesoscopic models of viscoelastic fluids with a non-monotonic flow curve

Julia L. Kuznetsova,Oleg I. Skul’skiy 한국유변학회 2016 Korea-Australia rheology journal Vol.28 No.1

The non-monotonic flow curve of a 1 wt.% polyacrylonitrile solution in dimethyl sulfoxide is described by two mesoscopic models: the modified Vinogradov-Pokrovsky model and the model proposed by Remmelgas, Harrison and Leal. To obtain an adequate description of the experimental curve, we have selected suitable internal parameters for these models. Analytical solutions for the Couette-Poiseuille flow problems are determined in parametric form, which allows us to plot the distribution of stress components and anisotropy tensor as well as the velocity profiles containing closed loops and weak tangential discontinuities. It is shown that both models predict a similar qualitative picture of structure evolution, but exhibit a significant discrepancy in the quantitative description of the magnitude of molecular chain stretching.

Анализ системы регионального oюджетного планирования в Приморском крае

( Natalia Victorovna Kuznetsova ) 국민대학교 유라시아연구소 2014 Eurasian Review Vol.6 No.-

This article is dedicated to the analysis of the basic tendencies of economic development of Primorsky Krai. Despite of the positive trend of growth, most of the indicators in the Primorsky Krai are significantly below than the national average and those of the Far Eastern Federal Territory. Contrasted with the declining share of industrial production, the main contribution to the GRP of Primorski Krai is made by the enterprises that are engaged in such sectors as transport, wholesales and retails. Economy of Primorski Krai has over-weighted and unstable structure of GRP, which can not provide high economic growth rates, high proportion of industries producing and processing raw materials (energy, fuel industry, metallurgy, etc.). The article evaluates the regional budget planning through the prism of the formation and implementation of the regional budget revenues and expenditures, and analyzes methodical aspects of improving the regional budget planning in the Primorski Krai.

Post-Agrogenic Self-Restoration of Soddy Podzolic Soils: Results and Methods N.P. Sorokina, D.N. Kozlov, I.B. Kuznetsova

Natalia Sorokina,Daniil Kozlov,Inna Kuznetsova 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

ENDOMORPHISMS OF PROJECTIVE BUNDLES OVER A CERTAIN CLASS OF VARIETIES

Amerik, Ekaterina,Kuznetsova, Alexandra Korean Mathematical Society 2017 대한수학회보 Vol.54 No.5

Let B be a simply-connected projective variety such that the first cohomology groups of all line bundles on B are zero. Let E be a vector bundle over B and $X={\mathbb{P}}(E)$. It is easily seen that a power of any endomorphism of X takes fibers to fibers. We prove that if X admits an endomorphism which is of degree greater than one on the fibers, then E splits into a direct sum of line bundles.

Endomorphisms of projective bundles over a certain class of varieties

Ekaterina Amerik,Alexandra Kuznetsova 대한수학회 2017 대한수학회보 Vol.54 No.5

Let $B$ be a simply-connected projective variety such that the first cohomology groups of all line bundles on $B$ are zero. Let $E$ be a vector bundle over $B$ and $X=\p(E)$. It is easily seen that a power of any endomorphism of $X$ takes fibers to fibers. We prove that if $X$ admits an endomorphism which is of degree greater than one on the fibers, then $E$ splits into a direct sum of line bundles.

Polymerization with Borane Chemistry. Tributylborane/p-Quinone System as a New Method of Reversible-Deactivation Radical Copolymerization for Styrene and Methyl Acrylate

Dmitrii Ludin,Yulia Voitovich,Evgenia Salomatina,Yulia Kuznetsova,Ivan Grishin,Igor Fedushkin,Sergey Zaitsev 한국고분자학회 2020 Macromolecular Research Vol.28 No.9

We report a reversible-deactivation radical copolymerization of styrene and methyl acrylate in the presence of tributylborane and different p-quinones. p-Quinones, such as 1,4-naphthoquinone, 2,3-dimethyl-1,4-benzoquinone, 2,5-ditert- 1,4-butylbenzoquinone, and duroquinone, with addition of a catalytic amount of tributylborane, allow for the control over styrene/methyl acrylate copolymerization. The process proceeds in a controlled manner via a reversible homolytic dissociation of the active macromolecules with terminal aryloxyboron-groups. The rate of styrene/methyl acrylate copolymerization depends on the inhibition constants of quinones. The molecular weight and molecular weight distribution of copolymers are directly dependent on the inhibitory abilities of the quinones. 1,4-Naphthoquinone and 2,3-dimethyl-1,4-benzoquinone act as the most effective mediators of chain propagation. Matrixassisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) results showed that the macromolecules contained internal fragments of p-quinone. Also, of the terminal aryloxyboron-groups were detected in the mass spectra. On realization of the “living” mechanism of copolymerization, the structure of copolymers obtained at high conversions can be considered as similar to the gradient structure. Stereo-regularity of the copolymers differed from the conventional radical copolymerization. The glass-transition temperature (Tg) of the gradient copolymer differed from Tg of the random compositional heterogeneous copolymer. The effect of the macromolecular structure on the mechanical properties of the copolymers was studied.

Properties of pitch-like materials obtained using coal extraction

Avid B.,Battsetseg M.,Purevsuren B.,Shiirav G.,Kuznetsov P. N.,Kuznetsova L. I.,Kamenskii E. S. 한국탄소학회 2022 Carbon Letters Vol.32 No.2

The bituminous coal was extracted with different industrial solvents like coal tar (CT), heavy cycle oil (HCO) and with their blends to determine the influence of solvent type on the extract yield, composition, thermal behavior, properties such as solubility to toluene and quinoline. The extracts obtained at 380 °C represented pitch-like solid matter with the softening points of 72–127 °C depending on the solvent used. They were characterized using the elemental and group analysis, FTIR spectroscopy, TG-DTG thermogravimetry and liquid chromatography for benzo(a)pyrene concentration. Also, maltene fractions of some extracts were studied by GC–MS. The results showed coal dissolution and the properties of the extracts to differ greatly depending on the solvent used. Coal tar was more favorable solvent for coal dissolution than HCO. Good correlation between the extract aromaticity and the content of the toluene insolubles was observed. The maltene fractions of the extracts obtained with CT and CT blended with HCO consisted mainly of polycyclic aromatics, and that obtained with the HCO contained also large amount of aliphatic compounds. It was found that the amount of the carcinogenic benzo(a)pyrene (BaP) in the toluene soluble fractions of the extracts were different depending on the solvents used for extraction. The remarkable result was that the BaP concentrations in all extracts were much lower than in the solvents used.