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.     

Chemical synthesis and characterization of manganese oxide coated Ni particles

Nanosized Ni particles with an average diameter of about 8 nm were prepared by reducing of NiCl 2 with sodium borohydride (NaBH 4 ) in aqueous solution. By moderate annealing in protective atmosphere, the composite grew up to be 15-20 nm particles. Both of the as-prepared and annealed Ni particles were coated by a layer of manganese oxide via decomposition reaction in aqueous KMnO4 solution. Hysteresis loops of as-prepared samples show a large increase in the magnetization with decreasing temperature and an unsaturated component at high magnetic field. In contrast, the ferromagnetic characteristics of annealed one are much stronger with large magnetization and coercivity. The thermomagnetic curves verified the coexistence of ferromagnetic Ni and antiferromangetic Mn oxide phases. But there exists no exchange bias behavior in the samples, even though the interface structure between the ferromagnetic Ni core and the antiferromagnetic manganese oxides has been distinctly formed. The absence of exchange bias probably originates from the weak ferromagnetic characteristic of Ni cores.