Interaction of Perfluorinated Fluids with Fluorine in Gas-Liquid Reactor

Russian Journal of Applied Chemistry - Process of fluorination of perfluorodecalin and perfluoro-1,3-dimethyl cyclohexane with fluorine in a gas-fluid reactor with a high-speed stirrer was...     

A volume formula for ℤ<Subscript>2</Subscript>-symmetric spherical tetrahedra

We obtain formulas for the volume of a spherical tetrahedron with ℤ₂-symmetry realized as rotation about the axis passing through the midpoints of a pair of skew edges. We show the dependence of the volume formula on the edge lengths and dihedral angles of the tetrahedron. Several different formulas result whose scopes are determined by the geometric characteristics of the tetrahedron.     

Photophysics of Semiconductor Polymer Nanocomposite with Fullerene C60 and Endohedral Metallofullerene Ho@C82

Physics of the Solid State - The photoexcitation energy transfer in donor–acceptor (DA) systems formed from a mixture of semiconductor polymer...     

Long-term luminescence of sensibilizers in tissues at the conditions of oxygen deficiency due to photodynamic effect

Long-term luminescence of organic dyes (xanthene dyes, halogen substituted fluoroscein) was used for an in vitro study of the photodynamic effect of exogenic probes in malignant tumors and healthy tissues of mice. It is shown that the photodynamic activity of oxygen and the dynamics of its concentration in tissues can be estimated from the delayed fluorescence of exogenic probes caused by singlet–triplet annihilation of singlet oxygen and excited triplet states of the molecules of photosensitizer dyes. It is found that quenching of long-term luminescence of photosensitizers significantly differs in tumors and normal tissues.

     

Allowance for the orientation of colliding ions in describing the synthesis of heavy nuclei

The dynamical model proposed earlier for describing fusion-fission reactions was modified in order to take into account an arbitrary orientation of colliding ions. In this model, the evolution of collective coordinates of the system under study is treated as a two-stage process. The motion of the projectile nucleus toward the target nucleus is considered at the first stage, and the evolution of a continuous dinuclear system formed as soon as the projectile and target nuclei touch each other is calculated at the second stage. At either stage of the calculation, the dynamical evolution of the system is described in terms of Langevin equations. The shell structure of the nuclei involved is taken into account at both stages. The difference between the results obtained for the first stage with allowance for an arbitrary orientation of colliding ions and the respective results for the case where their symmetry axes are aligned are discussed. The cross sections for the touching of primary nuclei and for their fusion are calculated, along with the cross sections for evaporation-residue formation in reactions involving nuclei that are prolate and spherical in the ground state. The results are compared with available theoretical and experimental data.     

Absorption technology of fine cleaning of nitrogen trifluoride from tetrafluoromethane

Scientific basis and equipment design of the industrial absorption technology of fine cleaning of nitrogen trifluoride from tetrafluoromethane are elaborated. Experimental investigations were performed on a laboratory installation, and the examination of results of absorption cleaning on the pilot plant was carried out. The final content of tetrafluoromethane, 10 ppm, in nitrogen trifluoride was attained.     

Global potential-energy surface for surface-charged clusters

We confirm the fission-barrier heights for surface-charged droplets obtained in earlier work within a very differently defined shape class. In addition we show that the Rayleigh-Taylor instability which occurs for spherical droplets for fissilities x > 1 is already seen for x = 0.9 in spheroids with sufficiently large eccentricity. We finally present an analytic formula for the electrostatic energy of two touching, surface-charged, conducting droplets.     

New indications of collinear tripartition in 252Cf(sf) studied at the modified FOBOS setup

An attempt has been made to search for collinear tripartition in spontaneous fission of ²⁵²Cf by using the FOBOS setup coupled with the neutron detector belt. A group of rare events were detected characterized by reduced total kinetic energy and total nuclear charge gated by the large neutron multiplicity measured. This fact is considered to be an experimental indication of collinear tripartition in ²⁵²Cf. The theoretical indication of the possible existence of the collinear cluster tripartition valley was obtained for the first time.     

Development and implementation of industrial technologies for synthesis of fluorine compound with the application of elemental fluorine

A survey is given on the application of elemental fluorine in chemical plants and research centers of Russian Federation.