Utilization of cellulose nitrate waste

A two-step procedure for utilization of cellulose nitrate waste accumulated at industrial enterprises of the Russian Federation was suggested and experimentally checked. The procedure involves hydrolysis of cellulose nitrate in alkaline medium and incineration of hydrolysis products. The best reagents for complete hydrolysis of cellulose nitrate are aqueous solutions of sodium hydroxide and sodium carbonate. As demonstrated by thermal analysis and thermodynamic calculations, incineration of cellulose nitrate base hydrolysis products can be performed without using hydrocarbon fuel.     

Determination of the effective nuclear charge from EPR data using a modified crystal-field theory

We propose a scheme for determining the effective nuclear charge Z _ef^CF of a 3d ion placed in a crystal field of arbitrary symmetry. As an example, we consider the Co²⁺ ion in a matrix MCO₃ (M = Ca, Cd). We show that the effective nuclear charge Z _ef^CF correlates with a change in the degree of the bond covalence.     

Optical properties of nanoplasmon excitations in clusters of endometallofullerenes

The optical properties of solutions of endometallofullerenes with lanthanides (Gd@C₈₂, Ce@C₈₂, La@C₈₂, Y@C₈₂) in dimethylformamide are studied. It is found that these solutions luminesce in the visible region. This luminescence is accompanied by enhanced Raman scattering. It is suggested that these processes are related to nanoplasmon excitations in clusters of endometallofullerenes. It is shown that the luminescence spectrum is described by a superposition of three to four Gaussian spectral profiles, whose energy positions and intensities nonmonotonically depend on the energy of excitation quanta. A detailed quantitative dependence of the intensity and shape of the Raman scattering signal on the concentration of endometallofullerenes in the solutions is determined. Comparative measurements are performed for the emission spectra of solutions of simple fullerenes and chromatographically pure endometallofullerenes. Complex investigations show that the visible luminescence and Raman scattering enhancement are only observed in the case of the formation of nanosized anionic complexes of endometallofullerenes in the solution.     

Research of the heat and mass exchange features of gas saturation into gas-liquid apparatus with high-speed agitator in a flow circuit

The saturation of a liquid phase with a gas and the heat exchange in a gas-liquid apparatus with a high-speed agitator in a flow circuit at various operating modes, constructions of the agitators were investigated and under various physical conditions.     

Reactions of fluoroalkyl-containing bis-β-diketones with hydrazine and hydroxylamine

Polyfluoroalkyl-containing bispyrazoles, bis(5-hydroxy-Δ²-isoxazolines), and bisisoxazoles were synthesized for the first time by reactions of polyfluoroalkyl-containing bis-β-diketones with hydrazine, phenylhydrazine, and hydroxylamine, respectively. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 762–764, April, 1999.     

On the Volume of a Symmetric Tetrahedron in Hyperbolic and Spherical Spaces

We obtain some elementary formulas for the volume of a symmetric tetrahedron in hyperbolic and spherical spaces.     

Gas-Phase Fluorination of Fluoroethanes with Elemental Fluorine

Scientific basis for industrial gas-phase fluorination of fluoroethanes with elemental fluorine allowing production of higher-fluorinated fluoroethanes from lower-fluorinated compounds is developed.     

Synthesis of perfluoroalkanes by fluorination of graphite with elementary fluorine in a vertical ascending gas-dust flow

Synthesis of lower pefluoroalkanes, tetrafluoromethane, hexafluoroethane, octafluoropropane, and decafluorobutane, in a high-temperature reaction of graphite with fluorine in a reactor with a vertical ascending gas-dust flow was studied.