Dynamics of current changes of the temperature field in the atmospheric surface layer above the territory of Siberia and Far East

The structure and dynamics of surface air temperature fields are investigated over the Asian part of the territory of Russia using the integrated approach suggested by the authors. The seasonal behavior of the average monthly temperature is established, the typical fields corresponding to this structure are determined, the long-term background trend is estimated, and the contribution of calendar months to its formation is determined.__________Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 81–92, November, 2004.     

Crystal structure of N-(β-acetoxyethyl)-4-methylpyridinium bromide

In continuation of previous studies [1] on structures of compounds differing from acetylcholine and choline by having a pyridine ring instead of the quaternary N atom, the x-ray structure of N-(-acetoxyethyl)-4-methylpyridinium bromide, which has cholinergic activity [2], is solved.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1813–1816, August, 1991.     

Polytrifluorostyrene-coated silica as a packing for column liquid chromatography

A reversed-phase hydrolytically stable packing material prepared by chemisorption of a trifluorostyrene-containing copolymer on to the surface of porous silica was tested by high-performance liquid chromatography of various aromatic compounds. It was found that the polytrifluorostyrene (PTFS) phase has an intermediate adsorption activity between those of polytetrafluoroethylene and polystyrene phases. A high selectivity of PTFS-coated silica in the separation of haloaryl compounds was observed. Wide-pore silica coated with PTFS was found to give an efficient resolution of peptides and proteins.     

A model of competing van der Waals interactions for describing the physicochemical properties of binary solutions of nonelectrolytes

A model of competing van der Waals (universal) interactions was suggested for describing the excess physicochemical properties of binary systems and excess thermodynamic functions of solvation. As distinct from the Redlich-Kister and Hwang polynomials, the coefficients of this model are functionally significant and related to various mechanisms of van der Waals, in particular, electrostatic interaction manifestations as the composition of the binary solvent changes. The suggested model was used to estimate the contributions of electrostatic nonstoichiometric interactions and mutual component destructuring effects to the observed physicochemical properties of binary systems. The empirical Dimroth-Reichardt solvatochromic scale of solvent polarities for binary systems was shown to be related to the electrostatic contribution of the model.     

Two-loop calculations for the propagators of gluonic currents

We calculate two-loop corrections to the propagators of gluonic currents$j_{PG}=\alpha G_{\mu v}^a{\overline{G}}_{\mu v}$ and j_SG = (β(α)/α)G_μν². The results of the calculations are used for finding the connection between the characteristic scales of quark and gluon worlds in perturbative QCD and for an estimate of the mass of the first radial excitation of the η′ meson [we obtain (m_η′)¹ = 1.55GeV].     

Synthesis,IR Spectra,and Steric Structure of Macrocycles Derived from Pyrimidine Compounds

A new macrocycle including pyrimidine fragments, 12,23,36-trimethyl-24,40-dioxo-15,33-dithia-2,9,13,22,26,35,38,39-octaazatetracyclo[32.3.1.110,14.122,26]tetraconta-1(38),10(39),11,13,23,34,36-heptaene, was synthesized. According to the data of IR and UV spectroscopy and HF/6-31G** quantum-chemical calculations, macrocyclic compounds of this series in crystal exist in the amino form, one NH group of which is likely to be involved in intramolecular hydrogen bond, and the other, in intermolacular hydrogen bond. The strength of the latter depends on the macroring size. In solution, the above structures are supplemented by conformers containing both intramolecularly H-bonded and free amino groups, predominantly with trans structure of the HÄNÄCÍN fragment. The imino form of the aminopyrimidine moieties is hardly probable.     

Aggregation and catalysis in a nonionic surfactant-polyethylenimine-chloroform system

The formation of polymer-colloid complexes (PCCs) of hydroxybenzylated polyethylenimines (PEIs) with poly(ethylene glycol-600) monolaurate (PM) in chloroform is established through dielcometric titration, light scattering, and viscometry. The effect of PCC on the PEI reactivity in phosphorylation with 4-nitrophenyl bis(chloromethyl)phosphinate is studied with spectrophotometry. It is found that the character of aggregates and the degree of their influence depend on the PM-to-PEI concentration ratio, polymer structure, and reaction temperature.     

Glycosides from <Emphasis Type="Italic">Stevia rebaudiana</Emphasis>

A new laboratory method for isolating the glycosides stevioside and rebaudiosides A and C from leaves of Stevia rebaudiana was proposed. According to HPLC, the glycoside contents in plants grown in Russia (Voronezh Oblast’) and Ukraine (Crimea) were 5–6% (stevioside) and 0.3–1.3% (rebaudiosides A and C). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 68–71, January–February, 2007