Cavitation model of self-recovery of a magnetic-fluid membrane

A cavitation model describing the process of the expansion and collapse of an empty spherical cavity in a nonviscous fluid has been proposed for interpreting the dynamics of breakage and self-recovery of a magnetic-fluid membrane. The theoretical conclusions agree with the results of experiment.     

Reductive transformation of isoprenoid cyclosulfonates into linear homoallylic alcohols and amines

Conclusions Isoprene, myrcene, and ocimene sultones were converted into the corresponding linear homoallylic alcohols and amines via the stage of desulfonylation of the in situ generated allylsulfinic acids. A new synthesis of myrcenol and isogeraniol has been carried out.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1820–1823, August, 1985.     

Radial characteristics of the stimulated emission of copper-vapor lasers

Copper-vapor lasers are currently under investigation with the definite aim of increasing the efficiency and mean power of such lasers. One way of doing this is to increase the repetition frequency of the pulse discharge and increase the volume of the active medium. However, if the interval between the pulses is reduced, cumulative effects begin to play a part in determining the state of the active medium before a new pulse. The main such effects are evidently the accumulation of heat, electrons, and metastable atoms. Ultimately, they reduce the pulse power and mean power of the laser. The reduction is characterized by the fact that the power of the laser emission decreases primarily in the center of the tube, and the transverse structure of the beam acquires an annular shape. Moreover, with increasing diameter of the working channel, these features are manifested at lower repetition frequencies. [1]. The present paper gives experimental data on this phenomenon and an attempt to explain it on the basis of the radial characteristics of the active medium.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 38–43, October, 1980.     

Free oscillations of magnetic fluid in strong magnetic field

The paper presents the esults of measuring the elastic parameters of an oscillatory system (coefficient of pondermotive elasticity, damping factor, and oscillation frequency) whose viscous inertial element is represented by a magnetic fluid confined in a tube by magnetic levitation in a strong magnetic field. The role of elasticity is played by the pondermotive force acting on thin layers at the upper and lower ends of the fluid column. It is shown that, by measuring the elastic oscillation frequencies of the magnetic fluid column, it is possible to develop a fundamentally new absolute method for determining the saturation magnetization of a magnetic colloid.     

Enantioselective Guest Effect on the Spin State of a Chiral Coordination Framework

The diversity of spin crossover (SCO) complexes that, on the one hand, display variable temperature, abruptness and hysteresis of the spin transition, and on the other hand, are spin‐sensitive to the various guest molecules, makes these materials unique for the detection of different organic and inorganic compounds. We have developed a homochiral SCO coordination polymer with a spin transition sensitive to the inclusion of the guest 2‐butanol, and these solvates with (R)‐ and (S)‐alcohols demonstrate different SCO behaviours depending on the chirality of the organic analyte. A stereoselective response to the guest inclusion is detected as a shift in the temperature of the transition both from dia‐ to para‐ and from para‐ to diamagnetic states in heating and cooling modes respectively. Furthermore, the Mössbauer spectroscopy directly visualizes how the metallic centres in a chiral coordination framework differently sense the interaction with guests of different chiralities.     

Elastic properties of a magnetic fluid with an air cavity retained by levitation forces

The paper describes the process of an air cavity rising in a magnetic fluid filling a tube with a bottom, transport, and retention of the cavity by magnetic levitation forces. The elastic and dissipative properties of a vibratory system with an inertial element that is a column of a magnetic fluid over an air cavity are considered. The possibility of using a transported air cavity as a movable reflector for a sound wave is evaluated.