Determination of the region of existence of ferromagnetic nanostructures in the paraphase of La<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>Ba<Subscript>x</Subscript>MnO<Subscript>3</Subscript> by the EPR method

In the paraphase of a number of La_1?x Ba_xMnO₃ single crystals with 0.1 ≤ x ≤ 0.2 below 340 K, signals of the ferromagnetic resonance are observed, which indicates the presence of magnetically ordered nanoscopic objects (ferrons). The region of the existence of ferrons on the Ba density-temperature phase diagram has an approximate triangular shape, which is characteristic of the Griffiths phase. Investigations of the angular and frequency dependences of the position of the ferromagnetic resonance line indicate that the nanostructures have a spherical shape. The parameters of their magnetic anisotropy are found to be H _a1 = 2500 Oe and H _a2 = ?700 Oe.     

Chemical transformations of betulonic aldehyde

Chemical transformations of 3-oxolup-20(29)-en-28-al in oxidation, reduction, reductive amination, aldol crotonic condensation, cyclopropanation, Grignard, and Wittig reactions were investigated. The structure of reaction products was established by X-ray diffraction (XRD) analysis.     

Properties of a Fireproofing Formulation Based on Liquid Glass and Mechanically Activated Aluminum Oxide

Moistening of filler particles with binder, curing, and high-temperature synthesis were studied in a liquid-glass formulation based on aluminum oxide. Selected kinetic parameters of these processes were determined. The influence exerted by the phase composition and mechanical activation on the adhesion, yield of the synthesis product, and basic properties of the formulation were analyzed.     

Analysis of the light scattering properties of a gold nanorod on a plane surface via discrete sources method

The Discrete Sources Method has been extended to analyze the scattering behavior of a gold nanorod deposited on a plane surface in an evanescent wave field. In this case the system particle-surface demonstrates no axial symmetry and it is not possible to apply the conventional DSM approach for axisymmetric systems used before. In this paper DSM algorithm for non-axisymmetric systems is presented. The rigorous computer model based on DSM, which allows to take into account all features of the scattering problem including particle-surface interaction has been realized. Computer simulation analysis of the scattering spectra of gold nanorod is presented.     

Influence of molecular structure on double ionization of N2 and O2 by high intensity ultrashort laser pulses

The electron momentum correlation after nonsequential double ionization of N2 and O2 in ultrashort light pulses at light intensities near 1.5 x 10(14) W/cm(2) has been investigated. The experimental results reveal distinctive differences between the molecular species and between molecules and atoms of similar ionization threshold. We provide evidence that recollision double ionization is the essential mechanism and trace the origin of the differences back to the symmetry of the orbitals occupied by the valence electrons.     

Synthesis and structures of Cu<Superscript>I,II</Superscript> complexes with a 2,2´-bipyridine derivative bearing a (+)-3-carene moiety

The complex salt {[CuL₂][Cu₄I₆]?MeCN}_n (1) and the compound [Cu₄L₃I₄]?3 MeCN (2) (L is a chiral ligand bearing a natural monoterpene (+)-3-carene moiety) were synthesized. The crystal structures of compounds 1 and 2 were determined by X-ray diffraction. The structure of compound 1 consists of complex cations [CuL₂]²⁺ (N₃O₂ polyhedron is a trigonal bipyramid) and Cu^I coordination polymers (CuI₄ polyhedron is a tetrahedron) as anions. The experimental magnetic moment μ_eff at 300 K is 1.90 μ_B, which is consistent with the X-ray diffraction data and the assumption that compound 1 is mixed-valence. The structure of compound 2 comprises a tetranuclear Cu^I complex, in which three Cu atoms are coordinated by two N atoms of the ligand L and two I atoms, and the fourth Cu atom is coordinated by four I atoms (coordination polyhedra are distorted tetrahedra). Compounds L and 2 were found to influence the viability of human laryngeal carcinoma cells (Hep2). The IC₅₀ value for complex 2 (13.0±1.7 μM) is substantially smaller than IC₅₀ for compound L (30.5±0.5 μM).