α-Ferrocenylalkylation of Some Biologically Active Compounds

Russian Journal of Organic Chemistry -     

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.     

Charge accumulation in dielectrics irradiated by protons

A phenomenological analysis of the electric charging of dielectrics irradiated by accelerated protons is performed. It is shown that the energy of the particles and their range in the material affect the accumulation of volume charge. The results of an experimental study of the charging of a number of dielectrics with different structures and properties are presented.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 75–80, May, 1987.     

Expanding sapphyrin: towards selective phosphate binding

The anion-templated syntheses and binding properties of novel macrocyclic oligopyrrole receptors in which pyrrole rings are linked through amide or imine bonds are described. The efficient synthesis was accomplished by anion-templated [1+1] Schiff-base condensation and acylation macrocyclization reactions. Free receptors and their host-guest complexes with hydrochloric acid, acetic acid, tetrabutylammonium chloride, and hydrogen sulfate were analyzed by single-crystal X-ray diffraction analysis. Stability constants with different tetrabutylammonium salts of inorganic acids were determined by standard 1H NMR and UV/Vis titration techniques in [D6]DMSO/0.5% water solution. According to the titration data, receptors containing three pyrrole rings (10 and 12) exhibit high affinity (log Ka=5-7) for bifluoride, acetate, and dihydrogen phosphate, and interact weakly with chloride and hydrogen sulfate. The amido-bipyrrole receptors 11 and 13 with four pyrrole rings exhibit 10(4)- and 10(2)-fold selectivity for dihydrogen phosphate, respectively, as inferred from competitive titrations in the presence of tetrabutylammonium acetate.     

Structure Constant and Grain Size Determination by Ferromagnetic Resonance in Thin Magnetic Films

Russian Physics Journal - The paper shows that the structure constant and the average crystal grain size of anisotropic nanocrystalline magnetic film can be determined by analyzing the shape of the...     

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.     

Self-similar solutions of nonstationary equations of a plane laminar magnetohydrodynamic boundary layer

Self-similar solutions of nonstationary equations of the boundary layer in ordinary hydrodynamics are discussed in [1, 2]. In this paper self-similar solutions of nonstationary equations of a plane magnetohydrodynarnic boundary layer are sought. In this case, a transformation to curvilinear coordinates of a certain special form is employed. Its choice is determined by the requirements essential to reducing the equations of the boundary layer to a system of ordinary equations. H. Weyl's iterative method is used to solve the equations describing the flow over a plate suddenly set in motion.     

Mobility of charge carriers in disordered dielectrics

We compare experimental data on the mobility of holes (the majority charge carriers) in polyepoxy-propylcarbazole, measured using the time-of-flight technique (drift mobility) and the nonsteady-state radiation-induced electrical conductivity method (effective mobility). We show that these two quantities are quite different in the dispersive transport regime; and while the second quantity is a characteristic of the material, the first quantity depends in a complicated fashion on the ratio of the electric field strength to the sample thickness. The untreated data on drift mobility measurements using the time-of-flight technique do not have direct physical meaning and cannot be compared with the conclusions of modern microscopic theories of the mobility of charge carriers in disordered matrices.High-Voltage Scientific-Research Institute at Tomsk Polytechnical University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 82–88, July, 1994.