Phase Transitions in Electro- and Magnetorheological Fluids

The model of internal structural phase transformations occurring in electro- and magnetorheological fluids under the action of external electric (magnetic) field is presented. The model describes both types of experimentally observed transformations such as the formation of linear chain clusters and bulk dense phases composed of suspension particles. The main qualitative result of this work is the conclusion that the appearance of chain clusters precedes the suspension separation into bulk phases with different particle densities and considerably affects the phase equilibrium diagrams. This conclusion agrees with the results of known experiments.     

Complexation of anion exchangers based on polyimines and allyl and epoxy compounds with transition metal cations

Complexation of polymeric anion exchangers with transition metals was studied by polarographic and potentiometric titration techniques.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 10, 2004, pp. 1693–1698.Original Russian Text Copyright © 2004 by Ergozhin, Chalov, Kovrigina, Iskakova, Nikitina.     

Structural Transformations in Polydisperse Ferrofluids

Real polydisperse ferrofluid is modeled by a bidispersed magnetic colloid composed of large and small particles. It is assumed that the energy of magnetodipole interaction for small particles is much lower and that of large particles is substantially higher than their thermal energy. Therefore, large particles can combine into the chain and droplet aggregates that are present in a sea of small particles. The influence of small particles on the structurization in the ensemble of large particles is studied. It is shown that small particles can either prevent or stimulate these structural transformations depending on the parameters of a medium.     

Regiocontrolled dieckmann condensation of 3,4-Bis(methoxycarbonylmethyl) levoglucosenone derivative

The Dieckmann condensation of 3,4-bis(methoxycarbonylmethyl) levoglucosenone derivative afforded two regioisomeric 9,11-dioxatricyclo[6.2.1.0^2,6]undecane derivatives at a ratio of 5: 3. The products can be used in the synthesis of iridoids.     

Wien effect in CuCl,CuBr and CuI superionic crystals and their melts

The dependence of conductivity of copper (I) halides (CuCl, CuBr, and CuI) and their melts on the electric field strength is studied. Conductivity of superconducting phases and their melts reaches limiting high-voltage values exceeding the usual values by up to 100% even at ∼0.5 MV/m.     

13C NMR Study of Polycondensation of Allyl Bromide,Diglycidyl Resorcinol Ether,and Polyethylenepolyamine

The features of polycondensation of allyl bromide, diglycidyl resorcinol ether, and polyethylenepolyamine were studied by ¹³C NMR.     

Criterion for the strong solvability of the mixed Cauchy problem for the Laplace equation

In the present paper, we prove a necessary and sufficient condition for the well-posedness of the problem indicated in the title in the space L ₂(Ω). To this end, we use expansions in the eigenfunctions of the mixed Cauchy problem for the Laplace equation with a deviating argument.