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Nazarov D.,Ural State University of Economics
Proceedings - CBI 2016: 18th IEEE Conference on Business Informatics | Year: 2016

The article offers a fuzzy model designed for working capital speed control. The model is based on minimizing the function of working capital immobilization as well as its derivatives with the use of the interval numbers arithmetic. The module approach allows on-going monitoring of the stock, accounts, receivable and financial resources using terms and concepts customary for economists and financiers. © 2016 IEEE.


Brainina K.Z.,Ural State University of Economics | Galperin L.G.,Ural State Technical University | Galperin A.L.,Ural Federal University
Journal of Solid State Electrochemistry | Year: 2010

A mathematical model is proposed that describes the processes of electrooxidation of metal nanoparticles localized on the surface of an indifferent macroelectrode. In contrast to previously proposed models based on geometric factors (shapes of particles and diffusion zones), the proposed model has introduced thermodynamic considerations which take into account the energy differences between the nanoparticle ensembles from microparticles and macroparticles. A series of voltammograms was obtained as a result of calculations and characteristic relationships between the different parameters were found. An analysis of the findings, on the one hand, predicts the shape and characteristic features of the experimental voltammograms and, on the other hand, provides information regarding energetic properties of the nanoparticles. © 2009 Springer-Verlag.


Brainina Kh.Z.,Ural State University of Economics | Galperin L.G.,Ural Federal University | Kiryuhina T.Yu.,Ural State University of Economics | Galperin A.L.,Ural Federal University | And 3 more authors.
Journal of Solid State Electrochemistry | Year: 2012

This article presents the findings of microscopic and electrochemical studies of electrooxidation of silver nanoparticles of varying sizes in comparison with "bulk" silver. Silver particles were immobilized on the surface of indifferent carbon-containing screen-printed electrodes. Vacuum-deposited silver represented the "bulk" electrode. The calculations and experimental studies demonstrated that the transition from macro- to nanostructural electrodes is followed by a shift of the maximum current potential of metal oxidation into the area with more negative potentials. A positive correlation between experimental and calculated data confirms once again a relevant application of the earlier proposed mathematical model and the possible use of the shift of the maximum current potential of electrooxidation to describe the electrochemical activity and surface energy properties of metal nanoparticles. © Springer-Verlag 2012.


Brainina Kh.Z.,Ural State University of Economics | Galperin L.G.,Ural Federal University | Vikulova E.V.,Ural State University of Economics | Galperin A.L.,Ural Federal University
Journal of Solid State Electrochemistry | Year: 2013

The paper proposes a mathematical model describing electrooxidation of a polydisperse system of metal nanoparticles from the surface of an indifferent macro-electrode. It is shown that the degree of dispersion of a nanoparticle ensemble affects the shape of oxidation voltammograms. When the degree of dispersion rises and the average size of nanoparticles becomes smaller, the range of oxidation potentials increases. The results of the experimental study of electrooxidation of gold nanoparticles with different degrees of dispersion are given. The particles were localized on the surface of graphite screen-printed electrodes. A good agreement between the parameters of the experimental and calculated voltammograms confirms the correctness of the proposed model. © 2012 Springer-Verlag.


Brainina Kh.Z.,Ural State University of Economics | Galperin L.G.,Ural Federal University | Vikulova E.V.,Ural State University of Economics
Journal of Solid State Electrochemistry | Year: 2012

It is shown that nanoparticles localized on a foreign solid electrode may display two opposite shifts of dissolution potential, namely, a shift toward either more positive or more negative values as compared with the equilibrium potential of M n+/M 0 or the potential of bulk metal electrooxidation. The observed phenomena are interpreted in view of three energy states of substance, which are realized depending on contribution of the surface Gibbs free energy (ΔG°) to the energy of the system. Literature data concerning different metalsubstrate pairs and specially conducted experimental investigations of electrooxidation of gold nanoparticles (radius equal to 10 and 150 nm), which are localized on the surface of glassy carbon, bulk gold, and platinum electrodes are presented and discussed. A shift of maximum current potential of small nanoparticles oxidation toward more positive values is observed in this series. The oxidation potential of large nanoparticles is not affected by the nature of the substrate. In all cases, electrooxidation of gold nanoparticles occurs at the more negative potentials than those of the bulk gold electrooxidation. It is shown that depending on the nature of the substrate and nanoparticle size, the dominating effect is either interaction of nanoparticles with the substrate (ΔG°<0) and electrochemical potential shifts toward positive values or impact of surface Gibbs free energy of nanoparticles (ΔG°>0) into energy of the system and electrochemical potential shifts toward negative values. The validity of the proposed assumptions is confirmed by good correlation of literature and our experimental data with calculated ones. © Springer-Verlag 2012.


Piankova L.A.,Ural State University of Economics | Malakhova N.A.,Ural State University of Economics | Stozhko N.Yu.,Ural State University of Economics | Brainina Kh.Z.,Ural State University of Economics | And 2 more authors.
Electrochemistry Communications | Year: 2011

Carbon screen-printed electrodes (CSPE) are used as substrate for bismuth nanoparticles immobilization. Sensors modified with bismuth nanoparticles of different origin (prepared by the method of gas condensation and chemically synthesized) are used to determine nickel by adsorptive stripping voltammetry (AdSV). The effect of the structural organization of nanoparticles on sensor sensitivity is studied. It is established that chemically synthesized nanoparticles of bismuth, which form agglomerates of about 380 ± 76 nm on the electrode surface, demonstrate optimal sensory properties. Direct current (DC) voltammetric stripping response is linear and is observed within the range from 0.85 × 10- 8 to 8.48 × 10- 8 M Ni(II) (deposition time - 120 s). The detection limit is 3.2 nM, precision is good (RSD = 4.8% at 5.0 × 10- 8 M Ni(II), n = 14). © 2011 Elsevier B.V. All rights reserved.


Sudakova L.A.,Ural State University of Economics | Malakhova N.A.,Ural State University of Economics | Stozhko N.Y.,Ural State University of Economics
Electroanalysis | Year: 2014

For the first time, carbon screen-printed electrodes (CSPE) modified with bismuth nanoparticles have been used to determine sulfide ions with stripping voltammetry (SV) by formation of sparingly soluble compounds with the electrode material. The impact of weight, degree of bismuth dispersion on CSPE surface, and Bi2S3 accumulation parameters on the sensitivity of the sensor have been studied. It has been established that bismuth nanoparticles (Binano) as agglomerates of about 180nm exhibit the optimum sensory properties. The linear concentration range has been observed over the interval of 0.93-5μM sulfide ions during the accumulation time of 75s. A detection limit of 0.15μM sulfide ions was achieved. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Kuzmin E.A.,Ural State University of Economics
Biosciences Biotechnology Research Asia | Year: 2015

A focus of the paper is a problem of "observability" regarding food security. Known scientific approaches to identification of a similar condition have not provided us with a grounded solution to refer to actual borders of security (or standards of mutual penetration). Their absence makes methodological capacities of modelling essentially disturbed. It is levelling of these contradictions that is an aim of this research. The authors put forward and give a scientific rationale for a hypothesis for fragmentary food security, an essence of which is come down to a research on certain agricultural commodity groups. In a critical review, features of security are specified. A theoretical development of authors' provisions have resulted in formalization of a number of models built in terms of the dependence factor or inherent openness of the food system. These and other features have made it possible to offer a distinctive technique for an analytical interpretation of findings, including an assessment of risk for lost security condition in a food aspect of the issue.


Nazarov D.M.,Ural State University of Economics
Proceedings of the 19th International Conference on Soft Computing and Measurements, SCM 2016 | Year: 2016

There is proposed a fuzzy model designed for working capital speed control. The model is based on minimizing the function of working capital immobilization as well as its derivatives with the use of the arithmetic of interval numbers. The module approach allows on-going monitoring of the stock, accounts, receivable and financial resources using terms and concepts customary for economists and financiers. © 2016 IEEE.


Brainina Kh.Z.,Ural State University of Economics | Varzakova D.P.,Ural State University of Economics | Gerasimova E.L.,Ural State University of Economics
Journal of Analytical Chemistry | Year: 2012

A novel version of a chronoamperometric method of antioxidant determination is described. It is based on the use of the oxidation current of ferrocyanide formed in the reaction of antioxidants to be determined with potassium ferricyanide as an analytical signal. So the total concentration of all antioxidants present in the analyzed solution, i.e., total antioxidant capacity, is measured. The results of blood plasma analysis by the newly presented and certified potentiometry method are in good agreement with each other, R 2 = 0.9980. The detection limit makes 2 × 10 -6 M for uric and ascorbic acids and 5 × 10 -6 M for cysteine and glutathione. © Pleiades Publishing, Ltd., 2012.

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