State of Atoms and Interatomic Distances in Complex Perovskite-like Oxides: XVII.1 Magnetic Dilution of La0.67Ca0.33MnO3 in LaGaO3

A magnetic susceptibility study of solid solutions of calcium-doped lanthanum manganite inlanthanum gallate showed that exchange interactions in clusters of manganese atoms do not change theircharacter with increasing temperature, unlike what is observed with solid solutions on the basis of lanthanumaluminate.     

Conducting Materials Based on Thermally Expanded Graphite

The electrical conductivity of composites produced from thermally expanded graphite, isoprene rubber, and polyvinyl chloride plastisol was studied as influenced by the process conditions.     

A bicontinuous structure in some systems with cubic mesophases

A cubic structure of polymer colloid complexes is studied. The technique of the research includes i) an analysis of well-known literature SAXS data; on this basis, ii) constructing a simple model to estimate geometric structure parameters and to obtain a simulated scattering curve; and iii) comparing the model with the real structure obtained from the SAXS data, using the reconstruction of electron density distribution. A bicontinuous structure in cubic mesophases is formed. Dedicated to the memory of Alexander T. Dembo     

Robust Output Tracking Control of an Uncertain Linear System via a Modified Optimal Linear-Quadratic Method

This study investigates the robust output tracking problem for a class of uncertain linear systems. The uncertainties are assumed to be time invariant and to satisfy the matching conditions. According to the selected nominal parameters, an optimal solution with a prescribed degree of stability is determined. Then, an auxiliary input via the use of an adapting factor, connected to the nominal optimal control, is introduced to guarantee the robustness and prescribed degree of stability for the output tracking control of the uncertain linear systems. This method is very simple and effective and can reject bounded uncertainties imposed on the states. A maglev vehicle model example is given to show its effectiveness.     

Effect of Potential on Coadsorption of Two Organic Substances in the Frumkin Model at a Maximum Possible Number of Solutions for the Relevant Set of Isotherms

Effect of the electrode potential on the coadsorption of two organic substances is studied using a set of two mixed Frumkin isotherms and a model of three parallel capacitors in conditions where in the absence of an electric field this system has seven solutions. It is shown that only four of these solutions may correspond to realizable adsorption states. Effect of the electrode potential on the number of possible solutions of the isotherm set, the number of realizable adsorption states, as well as on the composition and properties of a surface layer is considered.     

Bloch oscillations in a homogeneous nucleotide chain

It is shown that, at zero temperature, a hole placed in a homogeneous synthetic nucleotide chain with applied electric field demonstrates Bloch oscillations. The oscillations of the hole placed initially on one of the base pairs arise in response to disruption of the initial charge distribution caused by nucleotide vibrations. The finite temperature fluctuations result in degradation of coherent oscillations. The maximum permissible temperature for DNA “Bloch oscillator” occurrence is estimated.     

Absorption of cnoidal electromagnetic waves by superlattice electrons in the process of impurity ionization

Absorption of cnoidal electromagnetic waves, which are the most general periodic solution to the sine-Gordon equation, by electrons of a one-dimensional quantum semiconductor superlattice in the process of impurity ionization is studied in terms of the semiclassical approximation. The dependence of the absorption coefficient on the electric field of an electromagnetic wave is found to be nonmonotone with a pronounced peak.     

Effect of the Coulomb blockade of Cooper pairs on the dynamic properties of small-size Josephson junctions

The dynamics of Cooper pair tunneling under Coulomb blockade in small-size Josephson junctions is studied in terms of the resistive model. A relationship between the delay time and temperature fluctuations of the Coulomb blockade edge and the rate of rise of the voltage across the junction is derived.