Reactions of 2-(α-Haloalkyl)thiiranes with Nucleophilic Reagents: IV. Alkylation of Sulfonamides with 2-Chloromethylthiirane. Synthesis and Properties of 3-(Arylamino)thietanes

Alkylation of primary and secondary sulfonamides with 2-chloromethylthiirane in the presence of alkali gives the corresponding N-(thiiran-2-ylmethyl)- and/or N-(thietan-3-yl)sulfonamides. The selectivity of the process depends on the solvent: in water, thiirane-thietane rearrangement products are formed exclusively, while ethanol favors Ad-E reaction leading to thiiranylmethyl derivatives. A procedure has been proposed for the synthesis of 3-(arylamino)thietanes which undergo selective acylation at the nitrogen atom. The possibility for synthesizing analogous derivatives of thietane 1-oxide and thietane 1,1-dioxide is considered.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1046–1057.Original Russian Text Copyright © 2005 by Sokolov, Butkevich, Yuskovets, Tomashevskii, Potekhin.     

Unusual relaxation process in polybutadiene: Resolving the controversy

We report the observation of an unusual relaxation process in depolarized light scattering spectra of polybutadiene (PBD) with two different vinyl contents. The process showed up in the gigahertz frequency range with relatively mild temperature dependence and was similar to a secondary relaxation process. The most surprising observation was that the process exists even at high temperatures and does not merge with the segmental relaxation up to a temperature of 400 K (T > 2T_g). Possible mechanisms of this particular relaxation in PBD are discussed. The process is compared to the so‐called E process, double‐bond hopping process, and dielectric β process. We emphasize that this process differs from the dielectric β process, is unique for 1,4‐PBD, and has not been observed in other polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 994–999, 2004     

Generalized Heisenberg equations on ℤ-graded Lie algebrasLie algebras

We study the integrable systems of the Heisenberg equation type that correspond to different decompositions of ℤ-graded Lie algebras into a direct sum of two subalgebras. We discover new non-Abelian generalizations of some known integrable models. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 120, No. 2, pp. 248–255, August, 1999.     

Multicomponent generalization of the hierarchy of the Landau-Lifshitz equation

We construct a second-order 2N-component integrable system (with arbitrary N) whose spectral parameter lies on a curve of genus g=1+(N-3)2^N−2. The odd-order flows admit N-component reductions, which for N=3 coincide with the odd-order flows of the hierarchy of the Landau-Lifshitz equation. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 124, No. 1, pp. 62–71, July, 2000.     

Structure of the inhomogeneous magnetic state of an FeBO<Subscript>3</Subscript>: Mg easy-plane weak ferromagnet

The magnetic linear birefringence of an FeBO₃: Mg ferromagnetic crystal is investigated as a function of the magnetic field strength, the magnetic field orientation, and the coordinates. The structure of the inhomogeneous magnetic phase of this weak ferromagnet is determined by analyzing the experimental results obtained. It is shown that, in an inhomogeneous magnetic state, the ferromagnetic moment does not deviate from the basal plane of the crystal and the angle of its deviation from the direction of the applied magnetic field is described by a one-dimensional harmonic function of the spatial coordinate along the axis of magnetization.     

Quantitative analysis of pore space of moraine clay soils by SEM images

Problems of studying the pore space of moraine clay soils are considered by analyzing SEM images of the surface of samples prepared using a special technique. A new algorithm for estimating the pore shape is described. The study of the microstructure of moraine clay soils showed that they are characterized by five pore types. Of particular interest is the existence of large micropores with specific anisometric crescent shape in such soils. These micropores are formed at the interface between the surface of large sand-dust quartz or feldspar grains and the finely divided unoriented clay matrix. Such pores can be ways of localized groundwater filtration through soils, significantly affecting the soil properties.     

Coherent backscattering of nonmonochromatic light by an ensemble of cold atoms

The coherent backscattering of light by an ensemble of cold atoms in a magneto-optical trap is studied theoretically. The effect of the width and shape of the incident light spectrum on the enhancement factor and total intensity of the backscattered light is analyzed. The calculations are performed for ⁸⁵Rb atoms with allowance for the entire hyperfine and Zeeman structure of the ground and excited states of the atoms, spatial inhomogeneity of the atomic cloud, and motion of the atoms.     

Transformation problem for radiation with radial polarization

The propagation and transportation of laser beams with radial polarization (RP beam), possessing a high efficiency in their interaction with matter, are studied. The effect of different elements of an optical system on the polarization state of RP beams is analyzed. It is shown that optical systems with radial symmetry do not disturb the polarization of an RP beam and that the negative effect of a mirror on the state of polarization can be counterbalanced.     

Low-energy excited states of 3d transition metal ions in zinc selenide

The results of studying the impurity heat capacity of Zn_1?x M _xSe (M = Cr²⁺, Fe²⁺, Ni²⁺, Mn²⁺) solid solutions in the temperature range 1.8–20.0 K are presented. A heat-capacity method is described and applied for the measurement of the intracenter-transition energy in these systems. The role of the Jahn-Teller effect in the formation of low-energy excited states of 3d ions in ZnSe is discussed.