Behavior of metal complexes of polyacrylic acid in solutions

Metal complexes of polyacrylic acid containing Li, Li, and Cu, or Li and Zn have been studied in saline aqueous solutions using molecular hydrodynamics and light scattering methods. Intrinsic viscosities, weight-average molar masses, hydrodynamic radii, and radii of gyration were obtained. It was shown that the macromolecules of polymetalloacrylates containing divalent metals form small and large supramolecular structures, their dimensions, and composition being dependent on the ionic strength of the solution.     

The behavior of thermoresponsive star-shaped poly-2-isopropyl-2-oxazoline in saline media

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Studying surface vortices and potential fields in a conducting cylinder

The surface electromagnetic waves in a conducting cylinder are studied with allowance for the different polarization properties of a medium with respect to potential and vortex electromagnetic fields.     

Electrical properties of Cu1−x Ag x GeAsSe3 (x = 0.55–0.65) at low temperatures and high pressures

Chalcogenides Cu_1-xAg_xGeAsSe₃ (x = 0.55–0.65) are synthesized, and their electrical properties are studied at temperatures of 78–400 K and pressures of 15–45 GPa. The compounds are found to be mixed electronic-ionic conductors. Increasing the fraction of silver lead to an increase conductivity and shifts the region of considerable change in electrical properties at high pressures toward even higher pressures.     

Transcillatory heat transfer in a liquid with gas bubbles

The article describes the model of transcillatory heat transfer induced by gas bubbles buoyant in liquid. The temperature problem is reduced to the equivalent integral equation, and the velocity field in liquid phase is presented as structures of running and stationary waves. The relations for computing the coefficient of transcillatory transfer have been found.     

Development of dual-polarization reflectometry facility for Uragan-2M torsatron

The dual-polarization reflectometry facility developed for torsatron U-2M uses the extraordinary wave in addition to the ordinary wave. This is possible because the magnetic field of U-2M is produced by external conductors, is independent of plasma parameters, and is therefore a known quantity. The plasma probing is carried out simultaneously in a large number of pairs of close frequencies, which makes it possible to use superheterodyne circuits and, hence, considerably improves noise protection of the system and accuracy of measurement of phase shifts. The use of the extraordinary wave considerably broadens the range of the densities being measured in the given frequency band of generators. To reconstruct the density profile of the plasma from the frequency dependence of the phase shift of probing waves, original iterative algorithms have been developed for solving integral equations that are stable to experimental errors.     

Local field enhancement near spherical nanoparticles in absorbing media

It is shown by numerical simulation that the enhancement of the field near metallic nanoparticles is most significant in the transparency region of the matrix material and falls off as the absorption coefficient rises. In an absorbing matrix medium this leads both to an increase in the fraction of energy absorbed by the matrix material and to a substantial transformation in its spectral distribution. This is illustrated for the case of copper phthalocyanine with silver nanoparticles. By choosing the size of the introduced plasmon nanoparticles it is possible to enhance the absorption in the visible for the materials used in solar cells and thereby increase their energy efficiency.     

Side group functionalized liquid crystalline polymers and blends VIII. Nematic and SmAre phase formation in hydrogen-bonded blends of smectic side group LC polymers and a low molar mass dopant

Hydrogen-bonded blends based on smectic side group functionalized LC copolymers containing 4-alkyloxybenzoic acid fragments (proton donor) and a non-mesogenic low molecular mass dopant 4-cyanophenyl pyridine-4-carboxylate or 4-methoxyphenyl-d₄ pyridine-4-carboxylate (proton acceptor) were obtained. The blends containing 10-35 mol % of low molecular weight dopant form nematic (I-N-SmA) or re-entrant SmA phases (I-SmA-N-SmAre). The temperature dependence of the order parameter S, the birefringence Δn, and the splay K ₁ and bend K ₃ elastic constants of the nematic phase were studied by ²H NMR spectroscopy and the Fréedericksz method of threshold transitions in a magnetic field. A mechanism for the destruction of the SmA phase and the formation of the nematic phase in the hydrogen-bonded blends is suggested.