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Odessa, Ukraine

The National Academy of science of Ukraine is the highest research body in Ukraine, as a self-governing state-funded organization. It is the main research institution along with the five other academies specialized in various scientific disciplines. NAS Ukraine consists of numerous departments, sections, research institutes, scientific centers and various other supporting scientific organizations. The Academy reports on the annual basis to the Cabinet of Ministers of Ukraine.The presidium of the academy is located at the following address vulytsia Volodymyrska, 57, across the street from the Building of Pedagogical Museum where used to preside the Central Council during the independence period of 1917-18. Wikipedia.

Mishchuk N.A.,Ukrainian Academy of Sciences
Advances in Colloid and Interface Science | Year: 2010

The review addresses the peculiarities of concentration polarization caused by an electric current passing through conducting and around nonconducting charged materials. The conditions of emergence of an induced space charge of large density and thickness behind an electrical double layer, leading to strong non-linearity of electroosmosis and electrophoresis, are analyzed. Basic findings about concentration polarization, its theoretical modeling and experimental investigations, as well as its influence on electrokinetic phenomena and mass transfer through ion-exchange materials are discussed from the point of view of the fundamental knowledge about polarization processes and from the perspective of their practical application. The analysis focuses on the main properties of concentration polarization, electroosmotic flow of liquid around single fixed particles and through the system of particles, and electrophoresis of particles suspended in aqueous medium and current through flat, spherical and cylindrical interfaces and membranes with heterogeneous conductivity. The paper also presents the general ideas of concentration polarization and non-linear electrokinetic phenomena in case of nonconducting particles and their dependence on particle surface electroconductivity. Existing theoretical models describing polarization of nonconducting particles at high and low Peclet numbers are analyzed, with appropriate experimental data being provided to validate the theory. A joint analysis of polarization of conducting and nonconducting particles completes the review. © 2010 Elsevier B.V.

A complete and exact solution of the ground-state problem for the Ising model on the Shastry-Sutherland lattice in an applied magnetic field is found. The magnetization plateau at one third of the saturation value is shown to be the only possible fractional plateau in this model. However, stripe magnetic structures with 1/2 and 1/n (n>3) magnetization, observed in the rare-earth-metal tetraborides RB 4, occur at the boundaries of the three-dimensional regions of the ground-state phase diagram. These structures give rise to new magnetization plateaus if interactions of longer range are taken into account. For instance, an additional third-neighbor interaction is shown to produce a 1/2 plateau. The results obtained significantly refine the understanding of the magnetization process in RB 4 compounds, especially in TmB 4 and ErB 4, which are strong Ising magnets. © 2012 American Physical Society.

Kordyum E.L.,Ukrainian Academy of Sciences
Plant Biology | Year: 2014

A short overview on the effects of real and simulated microgravity on certain cell components and processes, including new information obtained recently, is presented. Attention is focused on the influence of real and simulated microgravity on plant cells that are not specialised to gravity perception and on seed formation. The paper considers the possibility of full adaptation of plants to microgravity, and suggests some questions for future plant research in order to make decisions on fundamental and applied problems of plant space biology. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

Lebovka N.I.,Ukrainian Academy of Sciences
Advances in Polymer Science | Year: 2014

This chapter reviews the recent progress in aggregation of colloidal particles with long-range interactions, including simple colloids and polyelectrolytes. The relevant interactions between colloidal particles, including Born repulsion, van der Waals, electrostatic, structural solvation, hydrophobic hydrodynamic interactions and attraction between like-charge colloids, charge nonuniformity, and adsorbed polymer, are analyzed. The main types of computer models used for simulation of cluster morphology and aggregation kinetics of the different interacting species (similarly and oppositely charged particles and polyelectrolytes) are reviewed. The main scaling laws for different aggregating kernels that describe diffusion-limited, reaction-limited, gelling, and retarded aggregations are also presented and analyzed. Graphical Abstract: © Springer-Verlag Berlin Heidelberg 2012.

Demchenko A.P.,Ukrainian Academy of Sciences | Tang K.-C.,Roosevelt Rd. | Chou P.-T.,Roosevelt Rd.
Chemical Society Reviews | Year: 2013

Charge and proton transfer reactions in the excited states of organic dyes can be coupled in many different ways. Despite the complementarity of charges, they can occur on different time scales and in different directions of the molecular framework. In certain cases, excited-state equilibrium can be established between the charge-transfer and proton-transfer species. The interplay of these reactions can be modulated and even reversed by variations in dye molecular structures and changes of the surrounding media. With knowledge of the mechanisms of these processes, desired rates and directions can be achieved, and thus the multiple emission spectral features can be harnessed. These features have found versatile applications in a number of cutting-edge technological areas, particularly in fluorescence sensing and imaging. © 2013 The Royal Society of Chemistry.

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