Variation of the dispersity and phase composition of a ferrous oxide catalyst in the burning of an ammonium perchlorate-polymethylmethacrylate mixture

Products of conversion of the ferrous oxide catalyst collected from the burning region of an AP-PMMA mixture show the significant aggregation of the catalyst, with large (40–50 m) spherical particles having a metallic glitter. Significant variations in the phase composition are observed, Fe₃O₄·-Fe₂O₃ solid solution and tetragonal and monoclinic Fe₂O₃ being formed.

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- a-Fe₂O₃ . . ( 40–50 ) . : Fe₃O₄·-Fe₂O₃, Fe₂O₃.

     

Crystal-chemical features of monoclinic lanthanide oxobromotungstates of composition LnWO4Br (Ln = Eu, Gd, Dy, Er, Yb)

The crystal-chemical properties of lanthanide oxobromotungstates of composition LnWO₄Br (Ln = Eu, Gd, Dy, Er, Yb) are studied. The crystal system and space group for the oxobromotungstates are determined. The unit cell parameters are refined. The parameters a, b, c, and V of the LnWO₄Br compounds are studied as functions of the atomic number of the lanthanide. Analytical equations are derived to predict unit cell parameters for unsynthesized lanthanide oxobromotungstates of the class in question.     

Operators of observables for a neutral particle with anomalous magnetic moment in an electromagnetic field

The explicit form of operators of kinetic momenta and spin projection for a neutral particle with an anomalous magnetic moment in constant homogeneous electromagnetic field is found. The possible applications of the obtained results in neutrino physics are considered.     

The propagation of wave beams in 2D cascade-induced lattices

A new method of 2D periodic lattices excitation in quadratically nonlinear media with cascade interaction is suggested. It is shown that in such structures the all-optical management of laser beams could be carried out. The possibility of switching waveguides and changing the final energy distribution among channels using the phenomenon of discrete diffraction is demonstrated.     

Electrostatic Potential and Adsorption Characteristics of the Trimethyl‐Silylated Surface of Silica

The distribution of electrostatic potential in the vicinity of the hydroxylated and trimethylsilylated surface of silica was calculated in the semiempirical PM3 approximation. A new mechanism is proposed for the bonding of electron-donating molecules with the surface of hydrophobized silicas.     

Dynamics of electron spin in undulators

The problem on the evolution of electron spin in inhomogeneous magnetic fields of special type is solved on the basis of the classical Bargmann-Michel-Telegdi equation. The results obtained are used to analyze the behavior of electron spin in magnetic undulators. Moscow State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 38–40, January, 2000.     

Cyclocondensation of α-acylacetamidines with esters of 2-fluoro-5-nitrobenzoic and 4-chloro-2-methyl-5-pyrimidinecarboxylic acids

The cyclocondensation of α-acylacetamidines with esters of 2-fluoro-5-nitrobenzoic and 4-chloro-2-methyl-5-pyrimidinecarboxylic acids leads to condensed azines. The reaction proceeds chemoselectively such that the α-carbon atom of the amidine replaces the halogen atom in the aromatic ring, while the amino group reacts with the ester group. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 589–594, April, 2008.