Orientation effects in fluorescence quenching for adsorbed aromatic hydrocarbons

Fluorescence quenching by a potential electron donor or acceptor has been examined for an aromatic hydrocarbon adsorbed on aerosil, for which unusual temperature effects have been observed, where the process is dependent on the nature of the quencher. These phenomena are examined in terms of reaction stereospecificity. By this is meant the resultant displacement from a series of jumps between localization positions. Surface Chemistry Institute, Ukrainian National Academy of Sciences, Prospekt Nauki 31, 252039 Kiev, Ukraine. Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 33, No. 1, pp. 12–16, January–February, 1997.     

On solutions of linear functional differential equations with linearly transformed argument on a semiaxis

We establish conditions under which solutions of a system of linear functional differential equations on a semiaxis are determined as solutions of a certain system of ordinary differential equations. __________ Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 4, pp. 501–513, April, 2007.     

On the existence of invariant tori of countable systems of difference-differential equations defined on infinite-dimensional tori

In the space of bounded number sequences, we establish sufficient conditions for the existence of invariant tori for linear and quasilinear countable systems of differential-difference equations defined on infinitedimensional tori and containing an infinite set of constant deviations of a scalar argument.     

On the asymptotic integration of a linear system of differential equations with a small parameter in the coefficients of some derivatives

Using a transformation matrix, we reduce a system of differential equations with a small parameter in the coefficients of some derivatives and a turning point to an integrable system of equations. We also study properties of the transformation matrix.     

Distortion of a matrix structure and the cluster formation in MnxZnyFezO4 ferrite single crystals

The evolution of the hard and soft modes in the crystal structure of Mn_xZn_yFe_zO₄ manganese-zinc spinel ferrites is investigated theoretically and experimentally (x-ray structure analysis and magnetic measurements). It is shown that tetragonal and rhombohedral distortions of the cubic structure and fluctuations of the soft mode are accompanied by the formation of clusters in the form of quasi-two-dimensional fragments (50–200 and 400–1200 Å), which involve families of γ-Mn₂O₃, γ-Mn₃O₄, and α-Fe₂O₃ oxide planes inherently bound to the spinel matrix.     

Boundary-value problems for differential equations unresolved with respect to the derivative in the space of bounded number sequences

We study a nonlinear countable-point boundary-value problem for a differential equation unresolved with respect to the derivative. This equation and a nonlinear boundary condition are defined in the Banach space of bounded number sequences. We study the reducibility of the posed problem to a multipoint boundary-value problem in a finite-dimensional space. __________ Translated from Neliniini Kolyvannya, Vol. 10, No. 3, pp. 391–415, July–September, 2007.