Oxidation of a galenite surface under the impact of nanosecond pulses

The effect of high-voltage nanosecond pulses on the phase composition of a galenite surface is investigated by means of XPES and IR Fourier spectroscopy. According to the XPES data, structural-phase transformations caused by pulsed treatment are mainly associated with variations in the chemical state of sulfur atoms, which determines the electrochemical and flotation properties of a semiconductor sulfide mineral: an increase in the electrode potential creates favorable conditions for adsorption of anion collectors and raises the flotation activity of galenite.     

Synthesis of Biomimetic Materials from Collagen and Hydroxyapatite

Russian Journal of Applied Chemistry - New approach is described to synthesis of biomimetic materials on the basis of hydroxyapatite particles and collagen suspension produced from fish-production...     

Synthesis,spectral properties,and conformations of nonlinear cross-conjugated polyenes containing pyrane or dihydropyridine fragment

New cross-conjugated ω,ω′-dimethylaminopolyenes containing the central pyrane or N-methyldihydropyridine fragment were synthesized. In new compounds, the interaction of the aminopolyene chromophores occurs through the dicyanomethylidene, 1-cyano-1-(4-nitrophenyl)methylidene, or 1,3-dioxoindan-2-ylidene groups in position 4 of the heterocycle. The conformation of the synthesized compounds was determined by 2D ¹H NMR spectroscopy (NOESY and ROESY): the chromophores are arranged at an acute or obtuse angle in the structures with the pyrane or dihydropyridine fragment, respectively. The conformational differences in polyenes result in a drastic change in their spectral properties: for the dyes with an acute angles between the chromophores, the long-wavelength absorption band is less intense, as a rule, than the shorter-wavelength band, while the situation is opposite for the compounds with an obtuse angle. The absorption spectra of the synthesized compounds with dinitrile and other acceptor groups lie in a longer-wavelength region than the absorption spectra of the corresponding compounds with carbonyl acceptor groups. The central bridging substituent NMe decreases the energy of interaction of the chromophores.     

Characterization of JBW-Algebras with Strongly Facially Symmetric Predual Space

Mathematical Notes - The present paper is devoted to the study of predual spaces of JBW-algebras. It is proved that the predual space of a JBW-algebra is a strongly facially symmetric space if and...     

Study of the Two-Dimensional Anisotropic Ising Model with Competing Interactions in the Region of a Transition from the Ferromagnetic to Paramagnetic State

Journal of Experimental and Theoretical Physics - The two-dimensional anisotropic Ising model with competing interactions in the region of a transition from the ferromagnetic to paramagnetic phase...